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236 Cards in this Set
- Front
- Back
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Anton Van Leeuwenhoek (1665)
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perfected the lens; discovered "animalcules" microorganisms under the microscope that he made. drew pictures and sent description to the Royal Society of London
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Who are the key scientist that disproved the Theory of Spontaneous generation?
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1. Francesco Redi (meat-> flies->eggs->worms)
2. John Needham (various infusions) 3. father Spallanzani (melted glass necks) 4. Louis Pasteur (Cotton plug w swan neck flasks) 5. John Tyndall (diff boiling times for diff types of infusions) 6. Ferdinand Cohn (demonstrated how important the type of infusion was to the experiment) |
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Francesco Redi
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demonstrated that worms came from the eggs of flies on decayed meat. He put a fine gauze over the meat and prevented the flies from laying eggs. thus no microorganisms
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John Needham (1749)
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made various infusions soaked hay, chicken broth, etc. boiled in water sealed w cork - infusions became cloudy and still had microorgansims
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father Spallanzani (1776)
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no air = no microorganisms
he made the same type of infusions but he melted the neck of the glass flasks and the infusions remained sterile. if glass cracked infusion became cloudy; this demonstrated that the air brought about the microorganisms. but people thought that air was the "vital force" that led to S.G. so teh argument continued. |
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Louis Pastuer (1861)
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demonstrated that the aiir is filled w microorganisms; filtered air w cotton plug in swan-necked flaskstrapping the organsims; looked at them under microscope; if cotton dropped into sterile solution - it became cloudy and the microorganisms multiplied quickly. ended argument of S.G.
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why did the swan-necked flasks keep the miicroorganisms out?
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pressure of the boiling water from an area of higher pressure to an area of lesser pressure. unequal forces of energy
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Who could not produce Louis Pasteurs results?
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John Tyndall (diff boiling times for diff infusions)
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John Tyndall
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noted that there are different boiling times for diff types of infusions; Ex.Hay - heat resistant organisms were brought into the lab and transferred to other infusions by way of dust particles in the air. this made it difficult to sterilize. he noted two types of cells - those that can be killed by boiling and those that are heat resistant (endospores)
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Who actually discovered and coined the term "endospores"?
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Ferdinand Cohn discovered endospores (cell that is heat resistant) in 1876
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Who demonstrated that anthrax was caused by Bacillus anthracis and how are they transmitted?
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Robert Koch in 1877 demonstrated that _______ was caused by Bacillus anthracis and that it was transferred by heat resistant endospores.
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What significant thing did Ferdinand Cohn note about these experments that tried to debunk Spontaneous generation?
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He noted that the experiments were not repeated exactly and scientists used diff types of infusions - Louis Pasteur used broths made from sugar and yeast extract and others who could not afford the resources that Pasteur could had to use less costly and easily obtainable infusions of hay and chicken broth. Hay was found to have close contact with soil - which has endospores in it.
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spontaneous generation
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the theory that living things can arise from non-living material.
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biodiversity
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the variety of species inhabiting a particular environment
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bioremediation
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the degradation of environmental pollutants by living organisms.
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domain
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the highest level in classification above the level of kingdom. All organisms can be assigned to one of 3 domains: Bacteria, Archaea and Eucarya
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Emerging Diseases
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Diseases that have increased in incidence in teh past 20 years
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eukaryote
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organism composed of one or more eukaryotic cells; members of the domain eucarya and eukaryotes.
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eukaryotic cell
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cell type characterized by a membrane-bound nucleus.
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normal microbiota
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the population of microorganisms that normally grow on the healthy human body or other specified environment.
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obligate intracellular parasite
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an organism or other agent that can only multiply inside living cells
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pathogen
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an organism or virus able to cause disease
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prokaryote
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single celled organsim consisting of a prokaryotic cell members of the domain Bacteria and Archaea are prokaryotes.
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prokaryotic cell
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cell type characterized by the lack of a membrane-bound nucleus
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who first observed bacteria and when?
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1665 - Antony van Leeuwenhoek
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Who finally refuted Spontaneous generation?
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Louis Pasteur (1861) and John Tyndall
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Give two reasons why it took so long to disprove the theory of spontaneous generation?
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1. the experiments were not being reproduced in identical format.
2. the scientists had not considered the types of infusions (sources of controls) that they were using and where they had originate from. For ex, Hay lies on soil (ground) and endospores thrive in soil thus transfer with the hay to whatever flasks causing a cloudy affect. |
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What experiment disproved the notion that a "vital force" in air was responsible for spontaneous generation?
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the cotton plug experiment by Louis Pasteur. he demonstrated through swan necked flasks and cotton plugs that filtered the particles in the air that the particles could not get through to the broth unless the experiment was manipulated by teh flasks tipping or the cotton plug being dropped intentionally into the broth or infusions - this proved that the spores or microorganisms were in the air. this confirmed the germ theory of diseases.
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Who created the first vaccine for rabies?
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Louis Pasteur
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Who disproved the theory of spontaneous generation? and thus confirmed the germ theory of diseases?
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Louis Pasteur in 1862
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Who are the 3 main founders of bacteriology?
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1. Louis Pasteur
2. Ferdinand Cohn 3. Robert Koch |
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Who worked tirelessly to find cures for diseases of animals (anthrax, chicken cholera) and of humans as well (rabies) and whose discoveries saved countless lives and provided great economic value to society?
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louis Pasteur - despite the public scrutiny he dedicated his life to finding the cause and cures to treat various ailments and diseases.
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Who is best known to the general public for describing how to stop milk and wine from going sour: And what is this process called?
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Louis Pasteur
This process was called pasteurization. |
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Who saw the 1st microorganism and when?
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robert Hooke in 1665 and published his discoveries of cells.
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Harvard College founded in US
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1636
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Egyptians ferment cereal grains to make beer
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1500 B.C.
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Who ntroduces the vaccination for small pox and when?
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Edward jenner in 1796
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Who suggest that invisible organisms may cause disease? and when
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Girolamo Fracastoro in 1546
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Antony van Leeuwenhoek observed bacteria in what year?
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1676
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What 2 scientists proposed that all organisms are composed of cells? and when
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Mathias Schleiden and Theodore Schwann in 1838-1839
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Who proposed the germ theory of disease and when? And who proved the germ thory of disease?
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J. Henle proposed the germ theory of disease in 1840, however, Louis Pasteur is regarded as the scientist who proved the grem theory of disease through his many experiments.
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What important thing did Ignaz Semmelwels contribute to biology?
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he demonstrated that child-bed fever is a contagious diseases transmitted by doctors during childbirth (1847-1850)
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What did John Snow demonstrate in 1853-1854?
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John Snow demonstrated the epidemic spread of cholera through a contaminated water supply (1853-1854)
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Louis Pasteur demonstrates that yeast can degrade sugar to ethanol and carbon dioxide in what year?
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1857
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Darwin publishes his book?
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Origin of Species in 1859
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In what year did Louis Pasteur refute spontaneous generation?
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1861
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In what year did Louis Pasteur develop pasteurization to destroy organisms in wine?
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1864
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Who publishes the first work on antiseptic surgery? and when?
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Joseph Lister in 1867
(Think Lister as in Listerment) |
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Who demonstrated that a bacterium causes anthrax? and when?
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Robert Koch in 1876
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What else is Robert Koch known for?
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he is one of the 3 founders of bacteriology and he demonstrated that a bacterium bacillus anthracis causes anthrax.
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What else is Robert Koch known for?
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1. he also introduces pure culture techniques in the laboratory in 1881
2. He discovered the cause of TB in 1882 (Tuberculosis) |
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Who introduced agar-agar as a solidifying gel for culture media (ex. petris dishes)? and when?
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Walter and Fanny Hesse in 1882
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Who discovered that a filterable agent , a virus, causes tobacco-mosaic disease? and when?
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Dmitri Iwanowski in 1892
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Who developed the drug salversan, the 1st chemotherapeutic agent to treat syphillis? and when?
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Paul Ehrlich in 1908
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Who discovered that a virus causes cancer in chickens? and when?
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F. Peyton Rous in 1911
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In what year did we have a world wide influenza epidemic?
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1918
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Who discovered genetic transformation in bacteria? and when?
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Frederick Griffith in 1928
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Who discovered the 1st antibiotic? What was the antibiotic? and when?
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Alexander Fleming discovered Penicillin, the 1st antibiotic in 1929
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What was Frederick Griffiths genetic transformations in bacteria? And what 3 scientists demonstrated this further?
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DNA or deoxyribonucleic acid.
demonstrated further by Avery, MacLeod and McCarty in 1944 |
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What 2 scientists demonstrated the transfer of DNA between bacteria? and when?
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Joshua Lederberg and Edward Tatum in 1944
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Barbara McClintock discovered what in 1948?
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she discovered transposable elements in maize in 1948
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Who determined the structure of DNA? and when?
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Watson
Crick Franklin Wilkins in 1953 |
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Who are the key scientists in the discovery of DNA and its processes?
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Frederick Griffith in 1928
Avery, MacLeod and McCarty in 1944 Joshua Lederberg and Edward Tatum in 1944 Watson, Crick, Franklin and Wilkins in 1953 |
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D. Carlton Gajdusek demonstrated what in 1957?
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he demonstrated the slow infectious nature of the disease kuru, later shown to be caused by a prion
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Who discovered the 1st restriction enzyme? and when?
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Hamilton Smith in 1970
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Who demonstrated the fundamental differences between viroids and viruses? and when?
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Theodor Diener in 1971
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What two scientists cloned DNA? and when?
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Herbert Boyer and Stanley Cohen in 1973
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What 3 scientists developed monoclonal antibodies? and when?
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Milstein, Kohler and Jeme in 1975
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Who discovered that cancer causing genes are in normal tissue? and when?
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Michael Bishop and Harold Varmus in 1976
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Who classified all organisms into 3 domains? and when?
What are the 3 domains |
Carl Woese
Bacteria, Archaea and Eucarya |
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a retrovirus causing a rare cancer in humans is discovered in what year?
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1980
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In what year did the WHO World Health Organization declare that smallpox was eradicated?
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1980
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In what year was the 1st product of genetic engineering introduced-human insulin?
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1982
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What3 science related things happened in 1982?
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1. 1st product of genetic engineering (human insulin)
2. Barry Marshall demonstrates that a bacterium causes ulcers 3. Stanley Prusiner isolates a protein; a prion from a slow disease infection |
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Who demonstrated that a bacterium causes ulcers? and when?
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Barry Marshall in 1982
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Who isolated a protein; a prion from a slow disease infection? and when?
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Stanley Prusiner in 1982
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Who invented the polymerase chain reaction? and when?
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Kary Mullis in 1983
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What 2 scientists isolate and characterize HIV, the human immunodeficiency virus? and when?
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Luc Montagnier and Robert Gallo in 1983
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In what year was the 1st complete nucleotide sequence of a bacterial chromosome reported?
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1995
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In what year did the FDA approve a genetically engineered food for human consumption
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1994
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Anton van Leeuwenhoek 1674
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used simple instrument to examine stagnant water, etc.
observed microscopic organisms called them "animalcukes" submitted detailed descriptions/drawings to the Royal Society of London question raised where did they originate? |
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Theory of Spontaneous Generation
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existed to explain the origins of some forms of life
Living organisms arose "sponatneously" from non-living, decaying matter believed to explain origin of "animalcules" |
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rancis Redi 1668
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performed experiments that disproved the theory of spontaneous generation for more complex forms of life
utilized jars of meat. some covered, some not. maggots appeared in uncovered jars; results not accepted for microscopic organisms; introduced experimental procedure for disproof of S.G. which took another 200 years to disprove |
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John Needham 1749
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Performed experiments similar to redi's
introduced the first culture medium for microbial growth Utilized infusion broth prepared by boiling meat, grain, etc. to extract nutrients; turbidity indicated growth; broth put in flasks, some were sealed with corks, some not; results were inconsistent - all flasks became cloudy; reasons: organisms in air of flasks, improperly sealed. |
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Lazarro Spallanzani 1776
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repeated Needham's experiments; broiled broth after placing in flasks; sealed flasks by melting necks; results more consistent with Redi's experiments; occasionally sealed flask --> cloudy; Not accepted b/c heating destroyed, degraded "vital force"/
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Louis Pasteur 1861
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performed experiments to disprove S.G.
filtered air thru cottton plug. Placed plug in infusion broths which became cloudy - organisms present in air; placed boiled infusion broths in "swan-necked" flasks; flasks remained sterile unless tilted or neck broken; His experiments disproved theory of S.G. Addt'l work: Pasteurization to prevent spoilage of wine and milk Introduced Germ theory of Disease after discovering silk worm disease caused by protozoan dev'd Pasteur treatment for preventing rabies using dried spinal cord from infected dogs |
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Edward jenner 1796
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dev'd small pox vaccination
used fruits from cow pox (vaccinia) lesions |
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Golden Age of Microbiology (approx. 1875-1918)
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Period of about 50 years of rapid development
causes of diseases identified; control methods dev'd; work began on viruses |
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Robert Koch
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while studying anthrax (a disease in cattle)
identified a bacterium as cause of anthrax (1st bacterium that caused a disease) he introduced a solid medium called agar. Observed differences in colony morphology; introduced the inoculating loop to transfer bacteria and prepare pure cultures; Introduced "Koch's Postulates" and the concept that a disease is caused by a single organism |
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Joseph Lister 1865
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introduced the "antiseptic technique"
Use of phenol (carbolic acid) as disinfectant |
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Martinus Beijerinck 1884-1885
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discovered filterable agents called "viruses" (toxins, poisons).
Assumed soluble toxin in filtrate caused disease called viruses "Latin for toxins, poisons |
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Paul Ehrlich 1910
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introduced concept of chemotherapy
use of salvarsan for the treatment of syphilis. |
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Alexander Fleming 1928
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Discovered the 1st antibiotic - penicillin
Prodeuced by mold that contaminated bacterial culture plate Led to discovery of other fungi that secreted antibacterial substances (antibiotics) |
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Read Medical Microbiology - Future Challenges --> summarize
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here
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Read Biotechnology - New Applications --> Summarize
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here
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Read Cell Theory --> summarize
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here
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Read Ch2 Biochemistry of the Molecules of Life --> summarize
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here
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characteristics of carbohydrates (molecule)
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Contain C H O with ration 1:2:1 of C:H:O
3 types - 1. monosaccharides (simple sugars, 3 to 6 C ex. glucose (6C), ribose (5C)) 2. disaccharides (consists of 2 monosaccharides ex. sucrose, lactose) 3. polysaccharides (composed of many monosaccharides ex. glycogen, starch) |
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characteristics of proteins (molecule)
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composed of A.A. (Amino Acids)
All amino acids contain an amine group, a carboxyl group and a variable radical (R) 20 diff A.A. in proteins A.A. joined together in chains by peptide bonds Peptide bonds occur between the amine group on one amonio acid and the carboxyl group on the adjacent A.A. Proteins differ in types, arrangement or sequence, number and shape (linear, coiled, folded) |
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characteristics of lipids (molecule)
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Triglyceride molecule composed of glycerol and 3 F.A. (Fatty Acids)
Many diff kinds of F.A. form many diff kinds; may be saturated or unsaturated: Saturated (C in F.A> joined by single bond & 2 H atoms) Unsaturated (adjacent C in F.A. joined by double covalent bonds & ea. C lacks a H atom) Polyunsaturated (contains many double bonds between C |
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Phospholipids
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composed of a glycerol, 2 F.A. chains & a Phosphate group
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Sterols
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such as cholesterol
Larger and more complex |
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Organic Compounds
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Cantains C atoms
most do not dissolve in water, those that will do not release ions large complex compounds covalent bonds include carbohydrates, proteins, lipids |
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Inorganic Compounds
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usually lack C
generally dissolve in water or dissociate to produce ions smaller in size than organic compounds usually held together by ionic bonds inorganic substances common in cells are water, O, CO2, inorganic salts |
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2 basic cell types
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eukaryotic "true nucleus" - more complex
prokaryotic "pre-nucleus" - simpler smaller |
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eukaryotic cells
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"true nucleus"
surrounded by nuclear membrane nuclear material organized into paired chromosomes nuclear membrane (DNA) assoc. w proteins called histones form the chromosomes nucleus contains nucleolus site of ribosome synthesis Internal str more complex; contains organelles ea. w specific fxn; ctyoplasmic streaming; cont movement of cytoplasm; cell membrane contains complex lipids - sterols (cholesterol); cell walls (only in plant cells, fungi & composed of chitin (cellulose); division occurs by mitosis, meiosis |
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Prokaryotic cells
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no "true" nucleus; no nuclear membrane; no paired chromosomes; no histones, no nucleolus; no organelles; no cytoplasmic streaming; cell membrane contains no sterols;
have cell walls composed of peptidoglycan (murein); divide by binary fission |
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Taxonomy
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study of classification
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Classification
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arranging organisms into related groups;
Phylogenic system based on evoluutionary relationships and str characteristics; Kingdom, Phylum, Class, Order, Family, Genus, Species; orig 2 kingdoms (before miroorganisms observed (animal, plant); did not work for microorganisms |
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System of Classification
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Based on following properties: cell type (prokaryotic, eukaryotic), str (multi or uni cellular); mode of nutrition/metabolism (ingestion, absorption,photosynthesis); str of DNA
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System of Classification continued.... Animal Kingdom
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eukaryotic (multicellular, ingestive)
All animals - sponges, worms, insects, invertebrates |
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System of Classification continued.... Plant Kingdom
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Eukaryotic (multicellular, photosyntheitic)
All plants - mosses, ferns, grasses, trees |
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System of Classification continued.... Fungi Kingdom
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eukaryotic (unicellular & multicellular, absorptive)
Yeast, filamentous molds, complex fungi |
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System of Classification continued.... Protista Kingdom
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eukaryotic (unicellular, few multicellular)
absorptive, ingestive, photosyntheitic algae, protozoa, slime molds |
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prokaryotae
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prokaryotic (unicellular, absorptive)
bacteria --> eubacteria (true bacteria) --> archaebacteria "ancient" (primitive) bacteria (extreme acidophiles/ thermophiles/ halophiles, methanogens produce methane gas from CO2 |
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What Kingdom do viruses fall into?
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None. The virus is not considered alive.
According to Cell Theory, in order for something to be considered "alive" it must be composed of Cells, and reproduce on its own. Since viruses cannot reproduce without the aid of a host, they fail the current rules of cell theory. Some scientists believe viruses are obligate parasites, and are indeed living. Viruses aren't placed in a classical kingdom or domain, however, they do have a taxonomic classification. |
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Scientific nomenclature
Binomial system - Genus |
written with a Capital /Upper case letter
group closely related organisms |
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Scientific nomenclature
Binomial system - Species |
written w lower case letter
group identical organisms |
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Scientific nomenclature
Binomial system - Strains |
indicated w numbers.letters
slight variations, but not enough difference to justify giving an organism a different species name |
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Scientific nomenclature
Binomial system - additionally |
printed in italics or underlined
may describe characteristics of the organism: 1. size 2. shape 3. arrangement - staphylococcus, Streptococcus 4. color of colony - Micrococcus roseus 5. Habitat - Escheria coli, Staphylococcus epidermidis 6. Nutritional requirements - Haemoplilus aegypticus 7. Disease - Neiseria meningitidis, N. gonorrhoeae, C. diphtheriae, V. cholerae 8. Researcher - Escherichia, Neisseria |
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Why could life on Earth not exist without bacteria?
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Life as we know it would not exist without bacteria to decompose waste and dead organisms. These bacteria ensure that the cycle of chemical exchange between organisms and their environment is continuous.
Bacteria are all around us and most people only consider these prokaryotic organisms to be disease causing parasites. While it is true that bacteria are responsible for a large number of human diseases, they also make it possible for certain elements such as carbon, nitrogen, and oxygen to be returned to the atmosphere. |
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Commensalism
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is a relationship that is beneficial to the bacteria which live off of the host, but does not help or harm the host. Most of the bacteria that reside within the bodies of humans are commensalistic.
For every 1 human cell, you have 20 bacteria (1:20 ratio) roughly 10% of your body mass. we live in symbiosis with bacteria. |
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mutualistic relationship
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both the bacteria and the host benefit. For example, there are several kinds of bacteria which live inside the mouth, nose, throat, and intestines of humans and animals. These bacteria receive a place to live and feed while keeping other harmful microbes from taking up residence.
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parasitic relationship
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is one in which the bacteria benefit while the host is harmed. Pathogenic parasites, which cause disease, do so by resisting the host's defenses and growing at the expense of the host. These bacteria produce poisonous substances called endotoxins and exotoxins which are responsible for the symptoms that occur with an illness.
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endotoxins
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are cell-associated substances that are structural components of bacteria. Most endotoxins are located in the cell envelope. In the context of this article, endotoxin refers specifically to the lipopolysaccharide (LPS) or lipooligosaccharide (LOS) located in the outer membrane of Gram-negative bacteria. Although structural components of cells, soluble endotoxins may be released from growing bacteria or from cells that are lysed as a result of effective host defense mechanisms or by the activities of certain antibiotics. Endotoxins generally act in the vicinity of bacterial growth or presence.
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exotoxins
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are usually secreted by bacteria and act at a site removed from bacterial growth. However, in some cases, exotoxins are only released by lysis of the bacterial cell. Exotoxins are usually proteins, minimally polypeptides, that act enzymatically or through direct action with host cells and stimulate a variety of host responses. Most exotoxins act at tissue sites remote from the original point of bacterial invasion or growth. However, some bacterial exotoxins act at the site of pathogen colonization and may play a role in invasion.
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Industry & Commercial use of bacteria
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Humans have exploited bacteria for a wide variety of uses, such as: making cheese and butter, decomposing waste in sewage plants, and developing antibiotics. Bacteria have been able to survive without us, but we could never live without them. (Ex.-cheese
-yogurt -sourkraut -pickles -antibiotics -sewage treatment -oil spill clean up -mining metals -fuels -insulin) |
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Toxigenesis
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or the ability to produce toxins, is an underlying mechanism by which many bacterial pathogens produce disease. At a chemical level, there are two main types of bacterial toxins, lipopolysaccharides, which are associated with the cell wall of Gram-negative bacteria, and proteins, which are released from bacterial cells and may act at tissue sites removed from the site of bacterial growth.The cell-associated toxins are referred to as endotoxins and the extracellular diffusible toxins are referred to as exotoxins.
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Bacterial protein toxins
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are the most powerful human poisons known and retain high activity at very high dilutions. The lethality of the most potent bacterial exotoxins is compared to the lethality of strychnine, snake venom, and endotoxin
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microbes (members of the microbial world)
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bacteria
archaea protozoa alae fungi some multicellular parasites non-living agents such as viruses, viroids and prions |
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biomass
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weight
for every human cell there are 10 bacteria cells 500 to 1,000 species of bacteria live on a healthy human body |
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what percent of microorganisms can actually be cultivated in a lab
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less than 1%
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why would we not exist without microorganisms?
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Nitrogen is the most common gas in the atmosphere
Plants nor animals can use N; Certain bacteria convert N into a form that plants can use. Without this we would die of Nitrogen asphyxiation |
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Nitrogen is safe to
breathe only when mixed with the appropriate amount of oxygen - here's why.. |
Nitrogen is not a “poison” in the
traditional sense. It presents a hazard when it displaces oxygen, making the atmosphere hazardous to humans. Breathing an oxygen- deficient atmosphere can have serious and immediate effects, including unconsciousness after only one or two breaths. The exposed person has no warning and cannot sense that the oxygen level is too low. The Occupational Safety and Health Administration (OSHA) requires employers to maintain workplace oxygen at levels between 19.5 and 23.5 percent. As shown in the table on page 3, the human body is adversely affected by lower concentrations. As the oxygen concentration falls below 16 percent, the brain sends commands to the breathing control center, causing the victim to breathe faster and deeper. As the oxygen level continues to decrease, full recovery is less certain. An atmosphere of only 4 to 6 percent oxygen causes the victim to fall into a coma in less than 40 seconds. Oxygen must be administered within minutes to offer a chance of survival. Even when a victim is rescued and resuscitated, he or she risks cardiac arrest. |
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Plants and microorganisms make O2
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Plants produce O2 on land and in aquatic environments; microorganisms all over produce O2.
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ruminant
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a mammal of the order Artiodactyla that digests plant-based food by initially softening it within the animal's first stomach, principally through bacterial actions, then regurgitating the semi-digested mass, now known as cud, and chewing it again. The process of rechewing the cud to further break down plant matter and stimulate digestion is called "ruminating".
Cellulose is degraded by billions of microorganisms in their digestive tracts. There are about 150 species of ruminants which include both domestic and wild species. Ruminating mammals include cattle, goats, sheep, giraffes, bison, moose, elk, yaks, water buffalo, deer, camels, alpacas, llamas, antelope, pronghorn, and nilgai. |
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what other ways do microorganisms degrade?
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waste water and sewage materials. This keeps stench low.
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Describe 5 applications in microbiology
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1. Food production
2. Bioremediation 3. sy6nthesize numerous products 4. medical use 5. genetic engineering |
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Food production in microbiology
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fermentation of milk to produce numerous products (yogurt, cheese, buttermilk, etc.)
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Bioremediation in microbiology
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Use organisms to degrade environmental waste
degrade PCBs, DDT clean up oil spills treat radioactive waste |
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Synthesizing products in microbiology
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bacteria can synthesize numerous products
-ethanol -pesticides -antibiotics -dietary amino acids |
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medical microbiology
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bacteria do not cause disease
more people died of influenze in 1918 than in ww1,ww2,Korean war, & vietnam combined modern sanitation , vaccinationand effective antimicrobial agents aid in reducing these diseases |
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genetic engineering in microbiology
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intro of genes of one oprganism into unrelated organism to confer new properties on the organism
help to produce vaccines, medical products, engineered plants resist disease; gene therapy |
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present challenges of microorganisms
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750 million cases ea. year in US alone
resulting in over 200,000 deaths costing tens of billions of dollars spent on health care. |
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Resurgence of microorganisms
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bacteria resistant to treatment come back even stronger; now resistant to antibiotics (ex. MRSA) Reasons incl increased travel due to greater technology (planes, trains, cars, etc.)travel to outside area where they have built up a tolerance but you have not, then you bring back home to US and get many others sick b/c we are not resistant. Also, many choose not to be vaccinated and so you never know who is and who is not vaccinated.
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probiotics
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the good bacteria that lies in our gut that destroys the bad bacteria and prevents intestinal disease and bowel cancer
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bioremediation
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the use of living organisms to degrade environmental pollutants found in contaminated soila dn water
also used to degrade oil in oil spills and to treat radioactive wastes a bacterium was discovered to live on TNT trinitrotoluene |
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what dangerous pollutants are destroyed or degraded by bacetria?
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PCB Polychlorinated biphenyls
DDT dichlorodiphenyltrichloroethane trichloroethylene (a highly toxic solvent used in drycleaning) and many more have been found in contaminated soil and water |
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TNT trinitrotoluene
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commonly known as TNT, is a constituent of many explosives, such as amatol, pentolite, tetrytol, torpex, tritonal, picratol, ednatol, and composition B. It has been used under such names as Triton, Trotyl, Trilite, Trinol, and Tritolo.
In a refined form, TNT is one of the most stable of high explosives and can be stored over long periods of time. It is relatively insensitive to blows or friction. It is nonhygroscopic and does not form sensitive compounds with metals, but it is readily acted upon by alkalies to form unstable compounds that are very sensitive to heat and impact. TNT may exude an oily brown liquid. This exudate oozes out around the threads at the nose of the shell and may form a pool on the floor. The exudate is flammable and may contain particles of TNT. Pools of exudate should be carefully removed. TNT can be used as a booster or as a bursting charge for high-explosive shells and bombs. |
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industry uses of bacteria
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cellulose used in stereo headsets
hydroxybutyric acid used in te manufacture of disposable diapers and plastics ethanol, as a substitute for gasoline - a "biofuel" chemicals poisonous to insects (for bug control) antibiotics used to treat diseases amino acids used in dietary supplements |
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smallpox
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worlds greatest killer over 10million dies in last 4,000 years
ex. hernando cortez w 600 soldiers conquered the Aztec Empire whose subjects numbered in the millions. Smallpox wiped out the Aztecs who had never been exposed to it before and had no immunity to the disease. Completely eradicated since 1977 |
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Plague
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another great killer - wiped out 1/3 of the entire European population (approx. 25 million people between 1346-1350)
now, less than 100 people in world die from this disease rodents on ships carried this bacterium and caused this plague. antibiotics controlled this disease |
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foot-and-mouth disease
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this was one of the most contagious diseases known to exist and almost 4 million pigs, sheep, and cattle were destroyed in England. To control this outbreak they had to slaughter all the animals and thus led to the starvation of millions.
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foot-and-mouth disease cont...
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Often inaccurately called hoof-and-mouth disease, this highly contagious virus causes blisters in the mouth and on the feet surrounding hoofs of animals with cleft, or divided hoofs, such as sheep, cattle and hogs. The disease was first noted in Europe in 1809; the first outbreak in the United States came in 1870. Although it seldom spreads to humans, it can be transmitted through contaminated milk or the handling of infected animals.
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emerging diseases
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Legionaires disease
toxic shock syndrome (tampons) lyme disease AIDS - acquired immunodeficiency syndrome hemolytic uremic syndrome mad cow disease (Bovine spongiform encephalopathy) west nile virus disease severe acute respiratory syndrome (SARS) hantavirus |
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hantavirus
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virus that infects rodents, usually w/out causing disease. They shed the virus in urine, feces and saliva - later to be inhaled by humans as an aerosol. this disease as well as Lyme Disease, are only two of many emerging diseases w/sm animal reservoirs.
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HIV Human Immunodeficiency Virus
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once could only infect chimpanzees, but now can infect humans. . HIV causes AIDS.
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SARS
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related to viruses found in animals transmitted to humans
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pathogens
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organisms capable of causing disease, differ from non-pathogenic relatives in that the pathogens contain large pieces of DNA that confer on the organism teh ability to cause disease
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Diseases found in US and when?
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1982 E.coli in US
1981 AIDS in US 1976 Legionaires' Disease in US Cryptosporidiosis in US 1989 Hepatitis C in US |
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Diseases found in South America and when?
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1991 Venezuelan hemorrhagic fever
1994 Brazilian hemorrhagic fever |
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Diseases found in UK and when?
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1988 Salmonella enteritidis PT4
1986 Bovine spongiform encephalopathy |
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Diseases found in Italy and when?
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1980 Hepatitis D (Delta)
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Diseases found in Africa and when?
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1976 Ebola hemorrhagic fever (aka Ebola virus) in Zaire
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Diseases found in India and when?
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1992 Vibrio cholerae 0139
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Diseases found in Malaysia and when?
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1999 Malaysian encephalitis
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Diseases found in Australia and when?
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1994 Human and equine morbilivirus
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Diseases found in Asia and when?
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1977 Hantaan virus (Republic of Korea)
1980 Human T-cell lymphotropic virus 1 (Japan) 1997 Avian flu (H5N1) in Hong Kong 2002 Severe acute respiratory syndrome (SARS) in China |
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H1N1
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2009 H1N1 (sometimes called “swine flu”) is a new influenza virus causing illness in people. This new virus was first detected in people in the United States in April 2009. This virus is spreading from person-to-person worldwide, probably in much the same way that regular seasonal influenza viruses spread. On June 11, 2009, the World Health Organization (WHO) declared that a pandemic of 2009 H1N1 flu was underway.
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Why is the 2009 H1N1 virus sometimes called “swine flu”?
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This virus was originally referred to as “swine flu” because laboratory testing showed that many of the genes in the virus were very similar to influenza viruses that normally occur in pigs (swine) in North America. But further study has shown that the 2009 H1N1 is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and bird (avian) genes and human genes. Scientists call this a "quadruple reassortant" virus.
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3 reasons for resurgence of old diseases?
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1. 1000's of foreigners and US citizens returning from travel from abroad (countries where malaria,cholera,yellow fever and plague still exist - now more fierce as causative agents are resistant to antibiotics)
2. childhood diseases controlled by vaccinations, but some parents become lax'd and fail to get their children vaccinated (ex. measles, polio, mumps, whooping cough, diptheria) 3. increasing proportion of elderly people with weakened immune systems. Also people with HIV susceptible to disesase (ex. TB and Kaposi's sarcoma) |
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Chronic diseases caused by bacteria
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peptic ulcer caused by bacteria Helicobacter pylori and is treatable with antibiotics. Indigestion affecting 25-40% may be caused by this bacterium.
Chrohns disease as well is caused by a bacterium |
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Host bacterial interactions
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skin all surfaces of body have bacteria - help to protect against disease. Normal microbiota or normal flora
they compete with disease causing bacteria and keep them from breaching our defenses that prevent disease. Bacteria degrade foodstuffs in intestine that the body cannot digest. |
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Normal microbiota or normal flora
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they compete with disease causing bacteria and keep them from breaching our defenses that prevent disease. Bacteria degrade foodstuffs in intestine that the body cannot digest.
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Pathogenic microbes
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including bacteria, fungi, protozoa, viruses - can damage tissues of body leading to sx's of disease. they use our body as a habitat to multiply, persist and transmit to other hosts. the sx's are offshoots of our defense mechanism which may damage host and pathogen.
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commonalities of the human cell and bacteria
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1. duplicate DNA in same way
2. degrade food in same way in order to harvest energy via the same metabolic pathways they are easy to study, inexpensive and grow rapidly making studies more efficient. |
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activities that microbes carry out that are essential to life on earth
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1. degrade Nitrogen - the Nitrogen Cycle
2. aid with production of antibiotics and vaccines 3, food production (yogurt, cheese, buttermilk) fermentation (beer) 4. |
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What is the Nitrogen Cycle?
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The nitrogen cycle is the set of biogeochemical processes by which nitrogen undergoes chemical reactions, changes form, and moves through difference reservoirs on earth, including living organisms.
Nitrogen is required for all organisms to live and grow because it is the essential component of DNA, RNA, and protein. However, most organisms cannot use atmospheric nitrogen, the largest reservoir. The five processes in the nitrogen cycle -- fixation, uptake, mineralization, nitrification, and denitrification -- are all driven by microorganisms. Humans influence the global nitrogen cycle primarily through the use of nitrogen-based fertilizers. |
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What is the Nitrogen Cycle?
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Nitrogen (N) is an essential component of DNA, RNA, and proteins, the building blocks of life. All organisms require nitrogen to live and grow. Although the majority of the air we breathe is N2, most of the nitrogen in the atmosphere is unavailable for use by organisms. This is because the strong triple bond between the N atoms in N2 molecules makes it relatively inert. In fact, in order for plants and animals to be able to use nitrogen, N2 gas must first be converted to more a chemically available form such as ammonium (NH4+), nitrate (NO3-), or organic nitrogen (e.g. urea - (NH2)2CO). The inert nature of N2 means that biologically available nitrogen is often in short supply in natural ecosystems, limiting plant growth and biomass accumulation.
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What is the Nitrogen Cycle?
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Nitrogen is an incredibly versatile element, existing in both inorganic and organic forms as well as many different oxidation states. The movement of nitrogen between the atmosphere, biosphere, and geosphere in different forms is described by the nitrogen cycle (Figure 1), one of the major biogeochemical cycles. Similar to the carbon cycle, the nitrogen cycle consists of various storage pools of nitrogen and processes by which the pools exchange nitrogen (arrows)
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activities that microbes carry out that are essential to life on earth
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1. degrade Nitrogen with nitrogen fixing bacteria in the Nitrogen Cycle
2. aid with production of antibiotics and vaccines 3, food production (yogurt, cheese, buttermilk) fermentation (beer) 4. degrading oil in spills 5. bioremediation 6. medical use 7. genetic engineering |
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What is the Nitrogen Cycle?
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The nitrogen cycle is the set of biogeochemical processes by which nitrogen undergoes chemical reactions, changes form, and moves through difference reservoirs on earth, including living organisms.
Nitrogen is required for all organisms to live and grow because it is the essential component of DNA, RNA, and protein. However, most organisms cannot use atmospheric nitrogen, the largest reservoir. The five processes in the nitrogen cycle -- fixation, uptake, mineralization, nitrification, and denitrification -- are all driven by microorganisms. Humans influence the global nitrogen cycle primarily through the use of nitrogen-based fertilizers. |
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What is the Nitrogen Cycle?
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Nitrogen (N) is an essential component of DNA, RNA, and proteins, the building blocks of life. All organisms require nitrogen to live and grow. Although the majority of the air we breathe is N2, most of the nitrogen in the atmosphere is unavailable for use by organisms. This is because the strong triple bond between the N atoms in N2 molecules makes it relatively inert. In fact, in order for plants and animals to be able to use nitrogen, N2 gas must first be converted to more a chemically available form such as ammonium (NH4+), nitrate (NO3-), or organic nitrogen (e.g. urea - (NH2)2CO). The inert nature of N2 means that biologically available nitrogen is often in short supply in natural ecosystems, limiting plant growth and biomass accumulation.
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What is the Nitrogen Cycle?
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Nitrogen is an incredibly versatile element, existing in both inorganic and organic forms as well as many different oxidation states. The movement of nitrogen between the atmosphere, biosphere, and geosphere in different forms is described by the nitrogen cycle (Figure 1), one of the major biogeochemical cycles. Similar to the carbon cycle, the nitrogen cycle consists of various storage pools of nitrogen and processes by which the pools exchange nitrogen (arrows)
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discuss several reasons for the reemergence of old diseases
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1. elderly people living longer with weakened immune systems and getting viruses from younger people.
2. more world travel and some countries still have significant diseases that the locals there are resistant to, but we are not. We get the diseases and bring it back to the states and spread the disease. more planes, trains, cruiseliners, etc. 3. another reason is that so many people today are getting vaccinated that parents are becoming more laxed and feel that their child does not need vaccines and so the child ends up getting the disease thru another child. |
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Why would it seem logical, even inevitable, that at least some bacteria would attack the human body and cause disease?
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because bacteria may mutate into various forms and severity and everyone's immune system is different.
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What are the 3 domains of life?
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Eucarya
Archaea Bacteria |
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characteristics of Eucarya?
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Eukaryotes have a nucleus with linear chromosomes that are much more complex. They are larger (about 10x) than prokaryotes, contain membrane-bound organelles, and are able to form multicelled organisms.
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characteristics of Archaea?
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Archaea and Bacteria are prokaryotes, they contain no nuclues or organelles, only a circular chromosome. They cannot form multicell organisms. Archaea are the more primitive of the 2, and can be found in extreme environments, such as hot springs and deep sea vents.
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characteristics of Bacteria?
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Archaea and Bacteria are prokaryotes, they contain no nuclues or organelles, only a circular chromosome. They cannot form multicell organisms. Archaea are the more primitive of the 2, and can be found in extreme environments, such as hot springs and deep sea vents.
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which 2 are prokarotes?
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archaea and bacteria:
prokaryotic means prenucleus they look identical no membrane bound nucleus no intracellular lipid-bound organelles genetic info stored in DNA in region called nucleoid genetically different though successful organisms and more likely to survive over eukarya. unicellular they have pilli and flagellum for movement Archaea are the more primitive of the 2, and can be found in extreme environments, such as hot springs and deep sea vents. they reproduce via binary fission they get variations thru mutations they replicate so quickly that it is easy to mutate also 2 bacteria can get near each other and one of their pilluses can connect from one bacteria to another and transfer DNA called bacterial conjugation archaea lack peptidoglycan in their cell walls bacteria are unicellular organisms;no nucleus;most have peptidoglycan cell wall |
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what is the 3rd domain?
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Eukaryotes
have a nucleus with linera chromosomes that are much more complex. They are larger (about 10x) than prokaryotes, contain membrane-bound organelles, and are able to form muticelled organisms. eukarya varies in composition ;contains carbohydrates |
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what is the R plasmid?
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a bacteria that developed through mutations that makes it resistant to antibiotics
R-factor is an old name for a plasmid that codes for antibiotic resistance Often, R-factors code for more than one antibiotic resistance factor: genes that encode resistance to unrelated antibiotics may be carried on a single R-factor, sometimes up to 8 different resistances. Many R-factors can pass from one bacterium to another through bacterial conjugation and are a common means by which antibiotic resistance spreads between bacterial species, genera and even families. For example RP1, a plasmid that encodes resistance to ampicillin, tetracycline and kanamycin originated in a species of Pseudomonas, from the Family Pseudomonadaceae, but can also be maintained in bacteria belonging to the family Enterobacteriaceae, such as Escherichia coli. |
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alexander fleming
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studying staphylococcus in a petri dish and saw that fungi had grown on center of petri dish and would not allow the bacteria that sat on the outer wall of the dish to come near it, so he determined that this blue green substance must be able to treat teh bacteria- penicillium fungus - created penicillin antibiotic
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Can bacterial cause mental imbalances?
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yes, depression, schizophrenia, lymes disease can cause mental disease, syphillis, etc.
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bacteria
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single celled
most have specific shapes - commonly cylyndrical (rod-shaped), spherical (round) or spiral rigid cell walls containing peptidoglycan (not found in any other organism) multiply by binary fission, mutate and replicate also via bacterial conjugation move via flagella and pilli |
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archaea
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same as bacteria except they do not have peptidoglycan in their cell wall
Archaea are the more primitive of the 2, and can be found in extreme environments, such as hot springs and deep sea vents. |
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where might you find archaea?
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they grow in places where salt concentration is 10x greater such as the Great Salt Lake and the Dead Sea
Can grow at temps of 121 degrees C 100 degrees C boiling point at sea level boiling hot springs at Yellowstone National Park widely distributed in the ocean, found in cold surface waters in Antarctica and Alaska |
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eukarya
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single celled and multi-celled
Protists (such as algae & protozoa) and fungi, Parasites such as helminths (roundworms and tapeworms) - these kill millions in 3rd world developing nations. |
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algae
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diverse group
single celled , others multi-celled many shapes sizes all contain chloroplasts - some have green pigment chlorphyll some with diff pigments and diff colors pigments absorb energy of lightused in photosynthesis found near surface of either salt or fresh water rigid cell walls chem composition diff from bacteria and archaea move by flagella - str is more complex |
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fungi
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also diverse
single celled yeasts many large multi-celled molds and mushrooms gain energy from degrading organic materials live mostly on land |
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protozoa
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diverse
microscopic single celled live in both aquatic and terrestrial environments very complex much larger than prokaryotes no rigid cell wall spec. shape based on gelatinous region just beneath the plasma membrane of cell require organic compounds as food source which they ingest as particles most are motile major feature is their means of locomotion |
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who created the binomial system of nomenclature?
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Carl Linnaeaus
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what is the first word in the naming system and its characteristics?
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genus and the first letter in the word is capitalized
also will be either italicized or underlined the genus name is commonly abbreviated with the first letter capitalized many diff species incl in the genus |
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what is the second word in the naming system and its characteristics?
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species and the first letter in the word is NOT capitalized but is lower case.
Also will be italicized or underlined may have many diff species but not enough to give it a new name, so they may add the word strain at the end. ex. E. coli strain B or E. coli strain K12 |
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Name one feature that distinguishes the domain Archaea from the domain Bacteria?
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1. bacteria's cell wall is made of peptidoglycan and Archaea is NOT
2. Archaea is most primitive and can thrive in extreme temperatures such as the boiling hot springs of Yellowstone National Park, cold surface waters of Antarctica and Alaska, and high salt regions such as the dead sea where there is 10x salt concentrations of normal waters |
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List two features that distinguish prokaryotes from eukaryotes?
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1. Prokaryotes are single celled and eukaryotes are both single celled and some multicelled
2. Eukaryotes lack peptidoglycan in their cell wall and Bacteria of the prokaryotes has peptidoglycan (Archaea does not though) 3. eukaryotes cannot withstand such harsh temps and extreme environments as the prokaryote can 4. eukaryotes have a membrane bound nucleus and organelles (mini organs in the cytoplasm of the cell) and prokaryotes do NOT |
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why bother using 2 names in the binomial system of nomenclature? Wouldn't it be asier to use a single name for each different type species?
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Not really b/c the species has so many variations and the name consists of the description of the shape and organization as well as the variations in naming it by a different strain. ex. strain B and strain K12 of E. coli
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What is a virus?
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Viruses infect living cells and once inside, transform the cell essentially into a factory for making more viruses. These acellular particles are composed of nucleic acid (genetic material), proteins and, in some cases, lipids as well
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How Do Viruses Reproduce?
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Viruses reproduce via four basic steps. Viral reproduction includes:
1.Delivery of the viral genetic material into a host cell 2.Commandeering of the host cell transcription and translation machinery 3. Use of the host cell’s building blocks to copy viral genomes and synthesize viral proteins 4.Viral genomes and proteins then self-assemble and exit host cells as new infectious particles. |
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Intracellular Viral Form
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Viruses exist in one of two states; extracellular and intracellular.
Once the virus invades a host cell it is in an ‘intracellular state.’ In this state, the capsid is removed and the virus exists as only as nucleic acid (genetic material). |
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Extracellular Viral Form
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Viruses exist in one of two states; extracellular and intracellular.
Before it invades a host cell, a virus is in the ‘extracellular state’. An extracellular virus, called a virion (vie-ree-on), consists of a protein coat (capsid) surrounding nucleic acid. In addition, some viruses have phospholipid envelope surrounding the capsid. |
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What Is a Viroid?
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Viroids are smallest known agents of infectious disease. Whereas viruses are made up of nucleic acid encapsulated in protein (capsid), viroids are uniquely characterized by the absence of a capsid. Thus far, this type of acellular particle has only been identified as an infectious agent in plants.
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What Is a Prion?
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Prions are an abnormal form of a normally harmless protein that cause various fatal neurodegenerative diseases called Transmissible Spongiform Encephalopathies. Once present in the brain, prions cause normal proteins to refold into abnormal shapes, destroying neurons and eventually causing the brain to become riddled with holes.
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Again, what are viruses, viroids and prions?
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they are not living
have no cells thus are acellular are termed agents |
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virus
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not living can only multiply inside living host
variety of shapes must reproduce copies of themselves in order to continue existing they use the hosts multiplication machinery and nutrients to multiply outside the hosts they are inactive called obligate intracellular parasites all life forms can be infected by viruses viruses frequently kill teh cells in which they multiply some can live in symbiosis without causing ill sx's |
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viroids
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simpler
single short piece of RNA without a protective coat much smaller than viruses and have to be inside the ghost in order to reproduce. cause plant diseases and possibly diseases in humans as well |
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Prions
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consist of only an abnormal form og a protein with no nucleic acid
responsible for at least 7 neuro-degenerative diseases in humans and animals always fatal |
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tobacco mosaic virus
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long hollow protein coat surrounds a molecule of RNA
(looks like long tubes or straws) |
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a bacterial virus (bacteriophage)
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infects bacteria
nucleic acid is surrounded by a protein coat (head) |
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influenxa virus
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thin section
infects humans causing flu |
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what tyopes of organisms do viruses viroids and prions affect?
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viruses - all forms of life
viroids - plants and scientists think is the cause in human diseases as well prions - humans and animals |
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how might one argue that viruses are actually living organisms?
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1. b/c given a favorable environment and the nutrients needed, they can reproduce
2. they have a piece of nucleic acid surrounded by a protein coat 3. they can exist (but must reproduce) in symbiosis with host |
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Heirarchy of the Microbial world
living organisms |
living organisms
domain(bacteria,archaea,eucarya) Bacteria & Archaea = prokaryotes unicellular Eukaryotes= algae (uni and multi cell) protozoa (uni cell) fungi (uni and multi cell0 helminths (multi cell parasites) infectious agents viruses = affect all life forms, viroids = affect plants and possibly humans prions = affect a humans and animals |
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Of the 3 non-living infectious agents, which are obligate intracellular agents?
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viruses and viroids
means that they have to reproduce in order to survive and can only do so by using the reproductive machinery and nutrients of their host |
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Of the 3 non-living infectious agents, which has abnormal form of cellular protein and no nucleic acid?
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prions
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Of the 3 non-living infectious agents, which has both RNA and DNA surrounded by a protein coat?
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viruses
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Of the 3 non-living infectious agents, which has RNA but no protein coat?
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viroids
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what is the diff or tehe range in size between the eukaryotes and the obligate intracellular parasites (aka viruses, viroids and prions)
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the obligate intracellular parasites are the smallest and the eukaryotes are the largest
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what factor limits the size of free living cells?
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size of the cell membrane. Cells obtain nutrients and eliminate wastes through the cell membrane. A cell must have a membrane surface large enough for all of the needed exchanges to take place with the environment. As cells increase in size, their need for nutrients increases, as does their production of wastes. Therefore, larger cells require a larger membrane surface area for survival.
The nucleus controls many of the cell's activities. It also has an effect on cell size. Control is vital to cell functions, and the nucleus can control only a limited amount of living, active cytoplasm. The scope of nuclear control, therefore, can limit the size of cells. |
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what happens to a eukaryotic cell when it grows beyond its limits?
and plant cells? |
the cell implodes.
plant cells are limited by their cell wall |
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Epulopisicium 1990's
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organism discovered in intestinal tract of certain fish in Red Sea in Middle East and Great Barrier Reef in Australia 600μm long and 80μm wide
cannot be cultured, macroscopic thought to be a eukaryote due to its large size at first but thru chemical analysis found to be a prokaryote (Bacteria) exception to teh rule that prokaryotes are always smaller than eukaryotes no membrane bound nucleus |
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Thiomargarita namibiensis 1991
"sulfur pearl of Namibia" |
Even lgr projkaryote found in sulfurous rock of ocean floor off coast of Namibia in Africa
spherical in shape 70x lgr than the Epulopisicium grows on sulfur compounds and contains glistening globules of sulfur |
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And scientists found a eukaryotic cell with a nucleus in the Mediterranean Sea that was 1μm even smaller than the prokaryotes
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the opposite of teh usual size
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how small can an organism actually be?
ex. Nanoarchaeum equitans "riding the fire sphere" N. equitans - an Archaea |
organism found in ocean vent off coast of Iceland, where temp close to boiling water, cannot be cultured, only grows when attached to a much lgr member of Archaea
attached to Ignicoccus "fire ball" 1/10 smaller than any known DNA in a cell resemble earlier cells and may be the ancestors of all life |
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coccus
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ball
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