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242 Cards in this Set
- Front
- Back
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What genera bacteria have Gram Negative Diplococci
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Neisseria (kidney beans)
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What are the pathogenic species of Neisseria?
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1) N. meningitides (meningococcus)
2) N. gonorrhoeae (gonococcus) |
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What causes meningitis and bacteremia and has a POLYSACCHARIDE CAPSULE?
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N. meningitides (meningococcus)
[genera neisseria] |
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Where do commensal bacteria of genera neisseria most often affect?
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Upper respiratory and alimentary tracts
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What are the features of N. gonorrhoeae (gonococcus)?
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cause of gonorrhea and has NO CAPSULE
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What are the features of the genera Veillonella?
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gram-negative anaerobic cocci
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What are the species of Veillonella?
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1) V. Parvula
2) V. Dispar 3) V. Atypical |
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How is Veillonella a beneficial bacteria?
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It metabolizes lactic acid to acetic and proprionic acids. It is found in higher numbers in healthy periodontia
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What are the 3 categories of bacteria based upon shape?
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1. Round: cocci
2. Rod: bacilli 3. Atypical form: spiral forms, spirochaetes (treponemas) |
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What are categories of bacteria based upon?
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1. aerobes
2. anaerobes 3. between 4. facultatives |
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What kind of bacteria can grow in air & use O2 to metabolize?
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Aerobes
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What kind of bacteria are sensitive to O2 & cannot grow in the air?
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Anaerobes
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What kind of bacteria are micro-airphillic?
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Between (but usually classified as aerobes)
campylobacter jejuni |
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What type of bacteria grow with or without oxygen?
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Facultatives
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What bacteria commonly accounts for endo & perio infections?
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(NB) Peptostreptococcus
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Name 2 sporing bacteriae
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1. Anthracis (aerobic)
2. Clostridium (anaerobic) |
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What is a lower level than species, when referring to bacteria?
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Strain
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How are bacteria names broken down?
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"genus" + "species"
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What shape are all streptococcus?
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round (cocci)
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What are 3 general gram + cocci?
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1. Staphylococcus
2. Streptococcus 3. Enterococcus |
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What is the difference between streptococcus & S. aureus
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color
streptococcus is white S. aureus is gold |
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What are 2 types of staphylococcus?
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1. S. aureus (gold)
2. S. epidermidis (on skin) |
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What type of cellular colonizer is S. aureus?
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Extracellular colonizer
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What is coagulase?
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Coagulase is an enzyme produced by Staphylococcus aureus that converts fibrinogen to fibrin. In the laboratory, it is used to distinguish between different types of Staphylococcus isolates. Coagulase negativity excludes S. aureus. (That is to say, S. aureus is coagulase-positive.)
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What is staph aureus' morphology?
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cocci, (S. aureus gold hue)
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Where are staphoreus bacteria located?
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everywhere
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What is staph aureus associated with and what is its impact on the body?
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Infections associated with hospitals. It is fatal
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What is used to diagnose staph aureus?
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special enzymes (like coagulase- clots plasma; protein A- antiphagocytic
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What bacteriae are capable of colonizing catheters?
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1. Staph epidermis
2. Staph saprophyticus (urinary tract infection) |
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What is an example of a toxin produced by staphylcoccus aureus?
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(TSS) Toxic shock syndrome toxin (shock, rash, desquamation)
KNOW THAT STAPH AUREUS MAKES A LOT of TOXINS |
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How is protein A of staph aureus antiphagocytic?
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Protein A has a high affinity for IgG. When staph aureus w/protein A encounter latex particles with IgG a visible agglutination of latex occurs (clumping together)
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What type of hemolysis shows as a narrow zone of partial hemolysis?
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alpha-hemolysis
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What type of hemolysis shows as a wide, clear, translucent zone of complete hemolysis around the colony?
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beta-hemolysis
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What are the cell wall components involved with functional redundancy?
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1. Protein F (springy type attachment)
2. M Protein (rod with "mini-skirts" going down the length) 3. Pili |
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WHAT ARE THE PROPERTIES OF S. MUTANS?
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1. colonizes on the tooth surface (supragingival)
2. acidogenic & acidotolerant attaches to tooth via glycan and glucan binding proteins |
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What type of bacteria is prevalent in endocdontic infections?
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Enterococci (gram + cocci)
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What are the important Gram + aerobic cocci to know?
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1. Staphylococcus (aureus & epidermis)
2. Streptococcus (pneumoniae, pyogenes) viridans group |
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what are the important Gram + anarobic cocci to know?
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enterococcus (E. fecalis)
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what are the important Gram - anarobic cocci to know?
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Veillonella (parvula, dispar, atypica)
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what are the important Gram - aerobic cocci to know?
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Neisseria (meningitidis, gonorrhoeae)
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What do atypical gram - bacteria form?
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spirochaetes
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What is a facultative anaerobe?
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can either go with or without O2
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What is the ecological term for the site where microorganisms grow?
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Habitat (skin, oral cavity)
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What is the ecological term for populations of individual species or less well defined groups growing in a particular habitat?
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microbial community
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What is the ecological term for species found characteristically in a particular habitat?
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Autochthonous microorganisms = commensal organisms
(original inhabitants) |
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What is the ecological term for species originate from elsewhere and are generally unable to colonize successfully unless the ecosystem is severely perturbed
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Allochthonous (exogenous) organisms (most pathogens)
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What is the ecological term for microbial community and its surroundings?
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Ecosystem
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What is the ecological term for organisms regularly isolated from a site, diseased or not?
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Resident microflora
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What is the ecological term for the role or function of an organism in a particular habitat?
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niche
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What is the ecological term for microorganisms with the potential to cause disease?
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pathogens
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What is the ecological term for species constantly associated with a particular disease?
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True Pathogens
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What is the ecological term for species that cause disease only under exceptional circumstances?
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Opportunistic pathogen
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What is the ecological term for stability of the composition of the resident microflora and the proportions of the component populations despite regular exposure to modest environmental pertubations?
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Microbial Homeostasis
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Why do we need resident microflora?
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If resident microflora are absent:
1. thin GI walls 2. poorly developed villi 3. poor nutrient adsorption 4. vitamin deficiencies 5. reduced host defenses 6. caecum enlargement |
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WHAT ARE THE PROPERTIES OF RESIDENT MICROFLORA THAT CONTRIBUTE TO COLONISATION RESISTANCE?
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1. competition for receptor sites for adhesion
2. competition for nutrients 3. creation of micro-environments that prevent growth of exogenous species (strep mutans) 4. production of inhibitory factors (bacteriocins) |
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What is the term for food products containing lactobacilli and/or bifidobacteria to enhance or restore the colonization resistance properties of the digestive tract?
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Probiotics
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What is the term for colonization of oral surfaces in infants with strains to prevent subsequent colonization by disease causing species?
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replacement therapy
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What is the ecological term for resident microflora is a significant barrier to exogenous (allochthonous) populations?
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Colonization resistance
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In addition to bacteria, what else exists in the healthy oral cavity?
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1. yeasts
2. mycoplasma (bacteria w/o cell wall) 3. protozoa 4. some viruses |
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What is another name for bacteroides fosythus?
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tannerella forsythia
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What are the key ecological factors in maintenance of microbial communities?
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1. appropriate receptors for attachment & colonization
2. essential nutrients and cofactors for growth 3. pH 4. redox potenial 5. gaseous environment 6. host genetics & social behavoir |
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What problems do you have associated w/ pH < 5.0?
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Aciduric environment (demineralization)
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What are glucans used for in the oral cavity?
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for attachment
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What problems arise in the oral cavity from a pH > 7.8?
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Perio
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what are fructans used for in the oral cavity?
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nutrient storage
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How is the acquired pellicle formed?
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Adsorption of host and bacterial polymers to tooth surface to form acquired pellicle
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How is the transport of microorganisms to the pellicle accomplished?
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flow of oral secretion
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What causes the long range REVERSIBLE interactions between microbial cell surface and pellicle coated tooth?
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Van der Waals attractive forces
Electrostatic repulsion |
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What are the short range IRREVERSIBLE interactions between?
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between microbial adhesions and receptors in the pellicle
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What do the fimbriae on the bacteria allow them to do?
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act as adhesins and allow the bacteria to colonize
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What bacteria cause ANUG?
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F. nucleatum spirochetes
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What bacteria cause adult perio?
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Red complex
Orange complex |
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What bacteria causes localized juvenile perio?
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A. actinomycetemcomitans
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What bacteria cause perio abcesses?
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P. gingivalis
Fusal bacterium |
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What bacteria causes generalized aggresive perio?
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A.A.
P. gingivalis small spirochetes |
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What bacteria causes refractory periodontitis?
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B. forsythus (T.F.)
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What is important re S. sanguis in development of plaque?
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1. It is an early colonizer of tooth surface (adheres to salivary molecules which form a pellicle on tooth surface)
2.important determinant in the development of plaque |
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What is important to know about genus actinomyces?
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Amphipathic (hydrophilic/hydrophobic) relationship with host
early colonizer |
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What allows A. naeslundii & A. viscosis to colonize?
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fibrils allow colonization
(principle adhesions & galactoside-specific lectin) |
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what type of pathogen is fusobacterium nucleatum?
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opportunistic pathogen
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Which bacterium isolates coaggregate with the widest variety of oral bacteria?
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Fusobacterium (periodontal disease)
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What is the dominant organism in a population of gram - bacteria that are rapidly replacing the gram + bacteria in gingivitis & periodontitis?
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Fusobacterium
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What is the most commonly isolated organisms in anaerobic infections?
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Genus Bacteroides (dumpster genus)
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What is the most important virulence factor for p. gingivalis?
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it is strongly proteolytic
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What is the pigmentation of BPB's?
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black pigmented bacteroids
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Which spirochete is very motile in highly viscous environment?
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Treponema denticola
(also proteolytic) |
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What are the filaments found on the outer surface of spirochetes?
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internal flagella
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What is the gram stain and motility of A.A. (actinobacillus actinomycetemcomitans)
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Gram negative rod
non-motile |
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What is the virulence factors for A.A.?
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* Leukotoxin (heat-labile, kills PMNs & monocytes)
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How do bacteria distribute in plaque?
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bacteria is not randomly distributed, it is in clusters (dental plaque columns)
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Does bacteria in periodontitis have to be in high numbers?
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no
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What does the red complex include?
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P. gingivalis
Tannerella forsythia (Bf) Treponema denticola |
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Which complex is located immediately adjacent to the epithelial lining of the periodontal pocket?
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Red complex
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Which complex is located between epithelial-associated biofilm & tooth-associated biofilm?
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orange complex
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Which complex is the epithelial-associated biofilm?
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Red complex
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What complex is the tooth-associated biofilm?
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purple
yellow green actinomyces |
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Where do all of the gram negative enterobacteria reside?
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in the gut
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What is the most important feature of the O antigen?
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LPS [lipopolysaccharide(O antigens are associated with the polysaccharides associated with the bacterial outer membrane)
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Where is the H antigen determined?
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peritrichous flagella- very motile & swim to nutrients(the H antigens are proteins associated with the flagella)
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What is the K antigen?
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Capsular antigens (associated w/polysaccharide)
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How is Escherichia coli labeled using antigens?
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O157:H7
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How many different strains of E. coli are there?
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hundreds
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What 2 areas in the body may you find Enterobacteriaceae?
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Lower GI tract
Female genital tract |
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What are the pili found in E. coli?
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Common: type 1
Specialized: P pili & CFA/BFP |
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What does the e. coli type 1 pili bind to?
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Type 1 pili bind to D-mannose
common on epithelial cells |
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What does the e. coli P pili (gal-gal) bind to?
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uroepithelial cells & erythrocytes
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What is the AB toxin that prevents protein elongation, causing cell death?
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Shiga & Shiga-like toxin
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What type of e. coli causes UTI?
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urinary tract infection is caused by UPEC (uropathogenic e. coli)
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What are the common species of Shigella?
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S. flexneri
S. dysenteriae S. sonni |
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What are the different types of e. coli that cause intestinal infection?
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1. ETEC (enterotoxic)
2. EPEC (enteropathogenic) 3. EIEC (enteroinvasive) 4. EHEC (enterohemorrhagic) 5. EAEC (enteroaggregative) |
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Which e. coli causes watery diarrhea, (3rd world) mortality < 2 yrs, CT/ST causing fluid outpouring in small intestine?
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ETEC (toxigenic, travelers' diarrhea)
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Which e. coli causes watery diarrhea, infants < 1yr old?
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EPEC (pathogenic)
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Which e. coli causes bloody diarrhea, < 5yrs old (3rd world)?
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EIEC (invasive, similar to shigella)
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Which e. coli causes bloody diarrhea accompanied by HUS (hemolytic uremic syndrome)?
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EHEC (hemorrhagic, O157:H7, may start w/vomitting & abdominal pain)
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Which e. coli causes watery diarrhea, biofilm on intestinal surfaces, children & infants in developing countries?
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EAEC (aggregative, weeks of diarrhea)
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When do symptoms appear when an individual has e. coli?
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2-4 days of ingestion of infectious dose.
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How long does e. coli diarrhea last?
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few days except for EAEC, which can last for weeks
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What qualifies as dysentery?
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diarrhea + WBC + RBC
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What causes dysentery, is spread via oral-fecal route, pediatric disease, stools contain blood & puss, and only requires <200 organisms?
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Shigellosis
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what type of bacteria may transcytose through M cells?
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shigella
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samonella has many names, but all regarded as different serotypes of __________.
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S. enterica
(S. enterica serotype typhimurium) |
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What causes infections that includes diarrhea lasting 3-4 days, comes from nursing homes & hospitals, animals, due to large scale food production?
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Gastroenteritis (S. enterica, samonella)
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Typhoid fever (serotype Typhi)is a type of samenellosis that differs from S. enterica because ______________.
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Typhi persist in macrophage longer than S. enterica, so it can cause bacteremia.
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What is the genus that includes the species:
1. Y. pestis (plague) 2. Y. pseudotuberculosis 3. Y. enteroclitica |
Genus Yersinia
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What does yersinia cause?
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gastroenteritis
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Once shigella enters a cell what does it use to make a jet?
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actin
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What are the virulence factors for enterobacteriaceae?
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1. pathogenicity island (PAI)
2. type III secretion (injects into cells like a syringe) |
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What are the toxins in Enterobacteriaceae?
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Endotoxin (LPS) & enterotoxin
exotoxin |
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How does shigella spread/move?
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Uses type III injection system to lyse the host cell vacuole
Protein triggers actin polymerization in host cell utilizing a rocket propulsion system to travel from cell to cell. |
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What are 2 different types of salmenosis?
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Salmonella & typhoid fever
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What is an example of a Vibrio?
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V. fisheri
(vibrios are curved rods commonly found in saltwater, facultative growth, single polar flagellum) |
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What bacteria grows under alkaline conditions, produces CT (cholera toxin), & has >150 O antigen serotypes
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Vibrio cholerae
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What is the composition of the CT (cholera toxin)?
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**********
AB toxin, 2 A subunits + 5 B subunits ********** |
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What produces the most dramatic WATERY diarrhea known?
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Cholera
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What is the source for cholera?
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contaminated water & under-cooked seafood
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What genus has motile curved rods w/polar flagella?
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Campylobacter
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What bacteria grows under microaerophilic conditions and is the MOST common cause of GI infection in developed countries?
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Campylobacter jejuni
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What is the most common source of C. jejuni?
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animals
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How is intracellular movement accomplished in C. jejuni?
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Microtubules (NOT actin)
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Which bacteria's infection is limited to the mucosa of the stomach?
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Helicobacter pylori
named for its shape (helical) makes it easy to penetrate & move in stomach mucosa |
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What allows Helico pylori to grow in the stomach?
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Urease (converts urea to ammonia -> ammonia raises the pH)
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What causes cell death in Helicobacter pylori?
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Vac A & Cag stimmulate inflammation & Vac A causes cell death
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What bacteria is aerobic but may also grow slowly under anaerobic conditions in the presence of nitrogen?
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Pseudomonas aeruginosa
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What bacteria is motile w/single polar flagellum and produces colorful water-soluble pigments?
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Pseudomonas aeruginosa
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What are 2 scarey infections for burn patients?
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1. psuedomonas
2. staphaureus |
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Why is psuedomonas the most difficult bacteria to treat, (due to its resistance to antibiotics)?
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it forms a biofilm
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What are the toxins that psuedomonas produces?
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1. exotoxin A (similar to DT)
2. elastase |
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Who are the most likely patients to acquire psuedomonas aeruginosa?
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1. Leukemia pts
2. CF pts 3. Burn pts |
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Why is it easier for P. aeruginosa to colonize & harder to clear, causing rapid pneumonia,in CF patients?
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Because of defects in the lung epithelial cells
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What genus in the smallest of bacteria, needs blood products for growth, & available in chocolate agar?
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Haemophilus
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Which strain of Haemophilus influenzae is the most virulent and contains a polyribitol phosphate (PRP) capsule?
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Type B (Hib)
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What bacteria is the major cause of meningitis, <2yrs old, & can progress to death in <1 day?
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Haemophilus influenzae
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What bacteria causes epiglottitis and pneumonia peaking at 2-5 yrs old, >90% due to Hib
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Haemophilus influenzae
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Where does Hib invade between?
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epithelial cells
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Are harmophilus bacteria trapped in the middle ear, sinuses, and bronchi capulated or non-capsulated strains?
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non-capsulated strains
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How does the haemophilus influenzae vaccination work?
|
Immunity is due to anti-PRP antibodies (occurences post vaccination are usually non-type B serotype)
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What causes whooping cough?
|
Bordetella pertusis
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What is the major virulence factor for B. pertusis?
|
pertusis toxin (PT), an AB toxin
adenylate cyclase tracheal cytotoxin |
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What are the two components of bordetella?
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1. adherence through filamentous hemagglutinin (Fha)
2. virulence regulated by two component system BvgAS |
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Where did Legionella pneumonia get its name from?
|
1976 american legion convention where it was first discovered
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Does legionella invade intracellularly or extracellularly?
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intracellularly in alveolar macrophages
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What disease does legionella pneumonia cause?
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legionellosis (destructive pnemonia w/headache, fever, chills, dry cough, chest pain, mortality rate high in immunocomprimised patients)
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What gram + bacilli is aerobic & facultative, small & pleomorphic?
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Corynebacterium (C. diptheria)
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What kind of toxin is DT?
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A-B toxin which inhibits protein synthesis irreversibly.
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How is C. diptheria spread?
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droplets & direct contact
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Which proteins are involved for initial invasion of cells? (Listeria Monocytogenes)
|
Internalin is used to enter epithelial cells
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Which proteins are required to spread to neighboring cells? (Listeria Monocytogenes)
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LLO (lysteriolysin O & ActA)
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What bacteria causes anthrax?
|
Bacillus anthracis
SPORE FORMING |
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What are spores resistant to?
|
heat & environment
Their capsule is antiphagocytic |
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What are Koch's postulates?
|
1. isolate bacteria from disease population
2. no disease, no bacteria 3. cure disease, cure bacteria 4. reinoculate in population w/o bacteria-disease |
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What type of vaccination is the B. anthracis vaccine?
|
attenuated virus- nonvirulent because it lost its plasmid for toxin production (louis pasteur)
|
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Name one beneficial place and one negative place that lactobacilli occur
|
Urogenital tract- good
Oral cavity- cariogenic (L.acidophilus & L.casei) |
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What is a large SPORE-FORMING, Anaerobic, gram + bacilli?
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Clostridia
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What are 4 important species of Clostridia?
|
C. perfringens (histotoxin)
C. tetani (neurotoxin) C. botulinum (neurotoxin) C. difficile (entero toxin A & cytotoxin B) |
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What bacteria has a double zone hemolysis?
|
C. perfringens (histotoxin)
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What bacteria causes tetanus?
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C. tetani (neurotoxin)
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What bacteria contains the most potent toxin known in nature?
|
C. botulinum (neurotoxin, lethal dose: <1mg
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What species of clostridia contains both enterotoxin (A) & cytotoxin (B) & you can never completely get rid of it?
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C. difficile
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What gram + bacilli composes the normal flora of the skin?
|
proprionibacterium
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What gram + bacilli composes the normal flora of the colon?
|
eubacterium
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What gram + bacilli causes mycosis, a cervicofacial infection due to poor dental hygiene, tooth extraction, or trauma to mouth/jaw?
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A. israelii (most common cause of actinomycosis)
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What type of colonizers are actinomyces in plaque?
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early colonizers
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What infections are A. odontolyticus associated with?
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Endodontic infections
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What genus bacteria is a strict aerobe, has high lipid content on cell wall (making it hydrophobic), & is difficult to stain?
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Mycobacteria
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What is PPD?
|
PPD = purified protein derivatives of tuberculin
(inject a little PPD, if you had TB your body would react) |
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How is the reactive form of TB confirmed?
|
Chest x-rays, chronic pneumonia w/fever, cough, bloody sputum, & weight loss
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What are these drugs used for:
isoniazid, ethambutol, rifampin, pyrazinamide, streptomycin |
FIRST LINE drugs for TB
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What are these drugs used for:
Para-aminosalicylic acid, ethionamide, cycloserine, fluoroquinolones, kanamycin |
SECOND LINE drugs for TB
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What bacteria comes in 2 forms: tuberculoid and lepromatous?
|
M. leprae
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Is there a vaccine for TB?
|
yes BCG vaccine is a live attenuated derivative of M. bovis (not used in US b/c of unpredictable efficacy)
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What does M. leprae cause?
|
chronic infection of the skin & peripheral nerves
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How does A-B toxin enter host cells?
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receptor mediated endocytosis
1. A-B attaches to cell receptor & is endocytosed 2. A releases & enters nucleus 3. EF-2 (elongation factor) binds A and it stops making polypeptide chain |
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What causes the inner clear zone in C. perfringens colonies?
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theta toxin (double zone of hemolysis, the wider zone of incomplete hemolysis is caused by alpha toxin)
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What is the pathogenesis of tetanus?
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1. puncture wound
2. exotoxin production 3. travels via neurons 4. blocks inhibitory neurotransmitters at MOTOR NERVE ends 5. respiratory muscle spasm 6. asphixia & death |
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What do the colonies of actinomyces israelii look like?
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molar tooth shaped
(colony morphology is very different) |
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Histopathological section from an actinomycetic lesion would show what?
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A branching filamentous mass infiltrating the bony cortex
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What is the gram negative diplococci (kidney beans) genus?
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Neisseria
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What are the 2 pathogenic species of neisseria?
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1. Meningococcus (meningitis & bacteremia, has polysaccharide capsule)
2. gonococcus (gonorrhea, no capsule) |
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Which species of Neisseria has a polysaccharide capsule?
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meningococcus
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Which species of Neisseria has NO capsule?
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gonococcus
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Where do commensal bacteria of Neisseria affect?
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upper respiratory & alimentary tracts
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What are 2 genera of gram-negative cocci?
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Neisseria
Veillonella |
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What genus is a gram - anaerobic cocci?
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Veillonella
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Where is Veillonella most predominant?
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in saliva and tongue surface
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Why is Veillonella considered a Beneficial Bacteria?
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It metabolizes lactic acid to acetic & propanoic acids
Higher number in perio healthy sites |
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What is unique to the morphology of Neisseria gonorrhoeae?
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they always exist in pairs (2 cocci)
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Which gram stain has the cell wall containing endotoxin?
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Gram +
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Which gram stain has a thick outer membrane?
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Gram -
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What is the relationship of transplacental antibodies to meningococcal disease?
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inversely related
you have low antibody 1st 20 yrs of life and higher risk of acquiring meningococcal disease that acquired antibody raises dramatically after ~years or so |
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How is gonorrhea spread?
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1. intercourse
2. oral-anal 3. oral-genital |
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Of those infected w/gonorrhea, who is most symptomatic?
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Males are most symptomatic
males: 95% symptomatic females: 50% symptomatic |
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What is important to know about gonococci regarding genomics?
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Antigenic variation due to pilE & 6 opa genes recombine to make 1
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What are the primary causative agents of intrauterine infection?
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***F. Nucleatum***
Ureaplasma urealyticum Mycoplasma hominis Bacteroides ureolyticus F. nucleatum is commonly found in the oral cavity and NOT commonly found in the vaginal tract. Possible link between periodontal disease & preterm birth. |
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Why can F. nucleatum persist in the placenta?
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Fn infection is cleared in the liver & spleen, but it is not cleared in the placenta
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What are the risk factors for preterm birth & F. nucleatum colonization in mouse placenta?
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Mouse pups death rate were dose dependent upon F. nucleatum injected into pregnant mice
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How does F. nucleatum get into the placenta?
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Commonly found in periodontal disease & may travel through the blood stream and enter vaginal tract.
Once F. nucleatum migrates to the vagina tract they can invade human mucosal KB cells and break into the uterus |
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What makes up the RED complex?
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1. Porphyromonas gingivalis
2. Tannerella forsynthisa (BF) 3. Treponema denticola Red complex is located immediately adjacent to the epithelial lining of the periodontal pocket |
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What makes up the ORANGE complex?
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1. Fusobacterium
2. Campylobacter 3. Prevotella 4. Eubacterium 5. Peptostreptococcus 6. Streptococcus constellatus Located between epithelial associated biofilm (RED) & tooth associated biofilm (purple, yellow, green, & Actinomyces complexes) |
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What is the black pigmented bacteriodes (BPB's)?
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The pigment is mechanism of storage of hemin
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What are the virulence factors for P. gingivalis?
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Virulence factors for P. gingivalis
1. proteases 2. hemagglutinins & fimbriae (allow adherence) 3. LPS (polysaccharide capsule) 4. vesicles (vehicles for enzymes & toxins) |
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What is the virulence factors for A. actinomycetemcomitans
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Leukotoxin (heat-labile, that kills PMN's & monocytes)
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How do Treponema denticola move?
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Internal flagella that wrap around the spirochete allowing them to move. Very motile in a viscous environment.
Associated w/chronic periodontitis, ANUG, & is part of the RED complex |
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Which long bacteria coaggregate with the widest variety of oral bacteria?
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F. nucleatum
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What are the characteristics of bacteriodes forsythus (tanerella forsythia)regarding cell shape & growth?
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Dome shaped structural subunits on outer layer
Difficult to grow due to a need for exogenous N-acetyl-muramic acid for growth |
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What are the microorganisms associated with dental caries?
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1. S. mutans*
2. S. sobrinus* 3. Lactobacili 4. Actinomyces spp. (root surface caries) 5. Veilonella (beneficial unless patient is immunocompromised) |
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What benefits do bacteria recieve from being part of a biofilm?
|
***
1. Antibiotic resistant 2. Resistant to phagocytes |
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What bacteria can be a pathogen or a beneficial species depending on host conditions?
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V. parvula- increases the pH be fermenting lactic acid preventing caries. AIDS patients it is associated w/periodontal disease
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Are planktonic cultures susceptible to phagocytes & antibiotics?
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YES ***
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Are biofilms susceptible to phagocytes and antibiotics
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No they are more resistant
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What are the sugars the bacteria produce for protection in biofilms?
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EPS-extracellular polysaccharides
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What bacteria has specialized P pili, which bind to uroepithelial cells & erythrocytes.
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Escheria coli ***
(P pili causes urinary tract infection because the form tight bonds w/uroepithelial cells) |
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What is the term for microorganisms living close together, which conjugate and exchange genetic material leading to the transfer of resistance/virulence factors.
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PAI (pathogenicity Islands)
(via horizontal transfer) |
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Where are PAI's located?
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1. phages
2. plasmids 3. bacterial chromosome |
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Many virulence genes are often clustered as ______
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PAI
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What bacteria produces watery diarrhea, traveler's diarrhea, CT/ST causing fluid outpouring in small intestines?
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ETEC
Toxigenic |
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What invades M cells?
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Shigella uses type III injection system
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What bacteria is strictly a human disease, persists in macrophages longer than S. enterica & may cause bacteremia, causing a fever. Can perist longer in stool.
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S. enterica serotype Typhi
(salmenollosis) |
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What are 3 important species of Yersinia?
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1. Y pestis (plague)
2. Y. pseudotuberculosis 3. Y. enterocolitica (underlying health problems causes gastroenteritis) |
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What are the common types of shigella?
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1. S. flexneri
2. S. dysenteriae 3. S. sonni |
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Shigella does NOT have flagella, so which antigen is it missing?
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H-antigen
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What do you treat C. diff with (according to Dr. Han, not everyone else in the world)
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Probiotics like lactobacili
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What is a beneficial metabolizing lactate, but suspected to be pathogenic in immunocomprimised?
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Veillonella
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