Organism and virulence factors Flashcards
(19 cards)
What are organisms that cause dental caries?
S. mutans, S. sobrinus, Lactobacillus casei, Actinomyces sp, Bifidobacterium sp, and low-pH tolerant Streptococcus sp.
What are 5 virulence factors of the bacteria that cause dental caries?
- adhesins (bind to tooth surface)
- acidogenicity (repid uptake and fermentation of CHO to lactic acid/acidic byproducts)
- aciduricity (the ability to tolerate, grow, and continue to make acid in acidic environments)
- EPS (synthesis of extracellular polymers or EPS from sucrose to consolidate attachment of the plaque to the surface of the tooth)
- Intracellular polysaccharides (production of these during periods of excess CHO availability which can be converted to acid during times when CHO is not available)
What virulence factors add the polymicrobials that cause periodontal disease (gingivitis and periodontitia)?
adhesins, hemolysins, and proteases (bind to surface and damage gingiva)
What causes viral stomatitis and what is its major virulence factor?
HSV and latency in host tissues
What causes fungal stomatitis and what is its major virulence factor?
Candida albicans - biofilm formation, germ tube formation (imbalance of host microbiota)
What causes Mumps and what is its major virulence factor?
Mumps virus - the hemagglutinin-neuraminidase on the virus bind to a trisaccharide containing an alpha2,3- linked sialic acid on host cells
What bacteria can cause PUD and what are 5 virulence factors?
Helicobacter pylori
- pH sensing (triggers urease production)
- produce flagella
- urease (making ammonium ions to buffer)
- Vac A (vacuolating toxin, creating pores in human cells)
- Cag A (changes host cell signaling)
What is the main cause of food poisoning in the US? Its virulence factor?
Staphylococcus aureus; 8 enterotoxins; heat stable
Which bacillus cereus type produces heat labile enterotoxins? What are they?
type II - hemolysin BL (HBL) and nonhemolytic enterotoxin
Which bacillus cereus type produces heat stable enterotoxin and what is it?
type I - depsipeptide cereulide
What is the virulence factor for clostridium perfringens causing food poisoning?
enterotoxin - binds to brush border membrane in the intestine and disrupts ion transport, altering membrane permeability.
Virulence factor for noninflammatory bacterial gastroenteritis from ETEC
two enterotoxins called LT and ST, stimulating secretion of chloride by host cells
Virulence factor for noninflammatory bacterial gastroenteritis EAEC
aggregative adherence fimbriae I (AAFI), enteroaggregative heat stable toxin, plasmid encoded toxin
Virulence factor for noninflammatory bacterial gastroenteritis from EPEC
makes no toxin - attaching and effacing histopathology in SI
Virulence factor for noninflammatory bacterial gastroenteritis from vibrio parahemolyticus
thermostable hemolysin (Kanagawa hemolysin ) - induces chloride ion secretion by increasing intracellular calcium levels
Virulence factor for noninflammatory bacterial gastroenteritis, cholera
cholera toxin - A-B toxin; B subunit binds to GM1 monosialoganglioside. A moiety migrates through epithelial membrane and catalyzes the transfer of ADP-ribose from nicotinamide adenine dinucleotide (NAD) to a GTP-binding protein that regulates adenylate cyclase activity; ultimately inhibiting chloride absorption and stimulating secretion into gut lumen
What is giardia lamblias virulence factor?
adhesive disk and parasite induced disaccharidase deficiency
What causes pseudomembranous colitis and what is its virulence factor?
C. diff - toxins A (interrupting tight junctions) and B (disrupts intestinal cell cytoskeletons through actin depolymerization)
Virulence factor allowing Inflammatory bacterial dysentery from Campylobacter jejuni, shigella sp, or EHEC
shiga toxin - interrupts protein synthesis by removing an adenine residue from the 28S rRNA in the 60S ribosomal subunit
