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24 Cards in this Set
- Front
- Back
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What is the systematic categorization of organisms into a coherent scheme?
What does it show? |
Taxonomy
evolutionary relationships among similar organisms |
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In bacterial nomenclature, what makes up the classic binomial system?
What are the 8 parts of taxonomic rank? |
Genus and species
Domain, Division, Class, Order, Family, Genus, Species, Strain |
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Linnaeus's 1753 classification scheme had what kingdoms?
What about Haeckel's 1866 scheme? |
Animalia: Animals, Protozoa. Plantae: Plants, Algae, Bacteria, Fungi.
Animalia: Animals Plantae: Plants, Multicellular algae Protista: Unicellular algae, Bacteria, Fungi, Protozoa. |
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Whittaker's 1969 classification scheme had what kingdoms?
Who and when discovered the current scheme? |
Animalia: Animals
Plantae: Plants Protista: Algae, Protozoa Fungi: Fungi Monera (Prokaryotae): Prokaryotes Woese in 1981 came up with 3 domains based on 16s rRNA sequence: Archaea, Bacteria, Eukarya |
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--Woese theory on Archaea--
Archaea came about in Lack BLANK BLANK in their cell wall, ether-linked branched BLANK BLANK chains in their membranes, lack a membrane bound BLANK, single BLANK chromosome several types of BLANK polymerases each with 8-12 subunits, BLANK ribosomes, amino acid carried by tRNA initiator is BLANK, tRNA BLANK absent and BLANK usually absent. Three main categories are... They grow slow and are found in... |
Archaean era 3.9 to 2.6 billion years ago.
muramic acid; aliphatic hydrocarbon; nucleus; circular RNA; 70s;methionine; thymine; dihydrouridine the methanogens, extreme halophiles, extreme thermophiles. thermal springs, methane deposits, etc. |
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What are the 4 approaches to identify and place microbes in a classification system?
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1. Classical approach: prokaryotes grouped into species and genera based on morphology, structural characteristics and then on biochemical & physiological traits.
2. Numerical taxonomy approach: all observable characteristics carry an equal weight. 3. Molecular approaches: based on nucleic acid comparisons. 4. Type strain: reference strain (ex: ATCC#####) |
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Describe the methods of numerical taxonomy
Both methods cluster groups into phenoms, i.e... When comparing several organisms, a computer is used to make a diagrammatic matrix called a BLANK Tested with an BLANK |
1. Based on the work of Michael Adanson, these methods compare the # of identical characteristics to the total # of characteristics observed in the organisms.
2. The matching coefficient method (Ss) is based on the % of characteristics that are common to 2 organisms when compared (both present or absent in both). 3. The similarity coefficient (Sj) method is based on the % of characteristics that are present in both but does not consider characteristics absent in both. species or genera in classical taxonomy. dendrogram enterotube |
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What are the 3 molecular approaches to taxonomy?
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Mol % G + C, Nucleic acid hybridization, DNA probes
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Describe the Mol % G + C molecular approach to taxonomy
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ds DNA is heated to the extent of the hydrogen bonding between the 2 strands is determined.
Melting temperature, Tm, the temperature at the midpoint of the absorbancy increase. A solution of ds DNA is slowly heated, its strands separate and denature, as the abs increases at 260 nm, it is followed in a spectrophotometer. Remember G≡C, A=T, therefore 3 hydrogen bonds harder to break than 2. Not used much anymore. |
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Describe the nucleic acid hybridization molecular approach to taxonomy
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Many methods developed to determine DNA homology between 2 organisms by comparing DNA-DNA, or DNA-mRNA.
One strain grown in the presence of radioactive thymine, which gets incorporated into newly synthesized DNA. The Second organism is grown non radioactively. DNAs are isolated from both strains and denatured into ssDNA and hybridized on a nitrocellulose filter. The extent of hybridization is determined by measuring the amount of radioactivity remaining in the hybrid molecules. Organisms related have a high degree of DNA homology than those that are unrelated. Good technique; developed probes used to ID strains. |
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Describe the DNA probe molecular approach to taxonomy.
Name an example of an organism difficult to culture in the lab. |
DNA probes are small base sequences that are specific and useful with organisms that are difficult to culture in the lab.
Ex: T. pallidum |
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What are the 5 volumes of Bergey's manual?
(Don't memorize, just review) |
Volume 1, The Archaea and the Deeply Branching and Phototropic Bacteria. (General Gram Negative Bacteria).
Volume 2, The Protobacteria Volume 3, The Low G + C Gram-Positive Bacteria Volume 4, The High G + C Gram-Positive Bacteria. Volume 5, The Planctomycetes, Spirochaetes, Fibroacteres, Bacteroidetes, and Fusobacteria |
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What is phylogeny?
What type of rRNA sequences are used to study it? How many nucleotides does it have? Who developed it & why? rRNA sequences could show you... |
the study of evolutionary relationships among living organisms.
16s rRNA; 1500 developed by Woese and Pace to demonstrate evolutionary divergence. had BT toxin and not b. anthracis |
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How is rRNA isolated?
cDNA is made from... PCR can also be used to... |
Cells are lysed, extracted with phenol, and the RNA ppt concentrated with alcohol and salt.
the rRNA template. amplify the rRNA genes (cDNA). |
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Describe the development of phylogenic trees
Signature sequences are short nucleotide sequences that are... |
The 16s rRNA sequences from different organisms are compared to determine phylogenetic relationships.
useful in defining the 3 domains. |
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In current phylogenetic tree, BLANK is more closely related to BLANK than to BLANK.
BLANK is the most primitive of the 3 domains, inhabiting primitive environments with extreme high temperature and low pH. |
Archaea; Eukarya; Bacteria/Prokarya
Archaea |
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What are the books associated with this science?
(Don't memorize, just review) |
Bakteriologische Diagnostik, Lehmann et al late 1800’s.
Manual of Determinative Bacteriology, Chester, 1901. Bergey’s Manual of Determinative Bacteriology, Bergey, 1923. The 9th edition published in 1994, separated prokaryotes into 35 groups. Bergey’s Manual of Systematic Bacteriology, 2001, 5 volumes |
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Describe the spirochetes.
What are the 5 genera of bacteria? |
1. Gram Negative
2. Slender, winding, or helical coiled cells 3. Outer sheath surrounds protoplasmic cylinder and periplasmic flagella. Spirochaeta, Christispira, Treponema, Borrelia, Leptospira. |
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--Spirochetes--
The cytoplasm and nuclear region are contained in a cell membrane–cell wall complex known as... Wrapped around the cylinder are BLANK flagella. The flagella are attached to one end of the cell and... The cells may have BLANK# to BLANK# of the flagella. |
the protoplasmic cylinder.
periplasmic flagella. extend most of its length. 2 to 100 |
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List the 5 spirochetes that are human disease agents and the disease they cause.
(Don't need to memorize all the other details but review them) |
1. Treponema pallidum causes syphilis. (Entry: genital; Incubation: 10-90 days; primary lesion: yes aka chancre; secondary lesion: yes aka septicemia (communicable)...then latent so no clinical manifestation; tertiary lesion: yes...tabes dorsalis "gummas"; congenital: yes)
2. Treponema pertenue causes yaws. (It is a tropical, non-sexually spread disease on soles of feet and palms of hand.) 3. Treponema carateum causes pinta. (A non-sexually tropical transmitted disease that causes hyperpigmentation of skin.) 4. Borrelia burgdorferi causes Lyme disease via a deer tick bite. (Found 1975 in Lyme, CT. Found in all 50 states. Incubation: 2-32 days. The rash is in 60-80%. Can cause cardiac and other issues if untreated; can treated with tetracycline.) 5. Leptospira interrogans causes leptospirosis. (Flu like symptoms and liver disease. Passed through rodent urine. Seen in urban settings.) |
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Other spirochetes live symbiotically with insects in their hindgut and...
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allow them to digest wood.
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What genus is among the largest bacteria known?
Where do they live and what do they do? |
Genus Spirillum
Live in freshwater and marine environments and are involved in recycling of matter. |
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--Genus Campylobacter--
Campys are BLANK negative, BLANK shaped bacteria with 1-2 polar flagella What is a specific example that is a human intestinal pathogen that causes gastroenteritis? Identifed in the BLANKs, transmitted from BLANKS to humans and isolated from... Occurs on the chicken and in BLANK# of poultry (cook chicken!) Environment liked is BLANK% oxygen. They penetrate the mucous layer of the small bowel, causes blood diarrhea, and produces BLANK |
Gram negative, curved shaped
C. jejuni 1970s; animals; diarrhetic stools 10^9g 5-10% enterotoxin |
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--Genus Bdellovibrio (Greek: leach)--
A small, curved, motile rod, that has the ability to... They usually attack and prey on... They live in the... Usually found in BLANK environments. Forms a BLANK and destroys the host. |
parasitize other bacteria.
LIVING Gram negative bacteria periplasmic space of these bacteria. aquatic bdelloplast |
