Flashcards in Oral Bacteria Deck (15):
The oral cavity is dominated by this bacteria:
(S. Mitis- all of mouth.
S. Sanguinis and S. Gordonni- tooth surface)
Early (pioneer) oral colonizer. Binds pellicle thru surface adhesins, provides binding sites for late colonizers (co-aggregation), produces H2O2 (inhibits S. mutans)
Streptococci (S. mitis, S. sanguinis, S. oralis, S. gordonii)
Early (pioneer) oral colonizer. Metabolizes lactic acid
Early (pioneer) oral colonizer. Binds to pellicle, other early colonizers and late colonizers (co-aggregation)
Late colonizer of oral cavity. Anaerobic but aerotolerant, co-aggregates, removes oxygen
Late colonizer of oral cavity. Strict anaerobe, asaccharolytic
Hypothesis that dental caries results from a perturbation in bacterial populations due to a disruption in the environment rather than a specific bacteria or infectious agent.
Non-specific plaque hypothesis
Etiological agent of dental caries. Mainly Serotype C in oral cavity.
Virulence factors of Streptococcus Mutans:
1. Acidogenic (metabolizes carbs -> acid production)
2. Acid Tolerant- more tolerant than commensal bacteria
3. Glycosyltransferases- enzymes that form polymers of glucose from sucrose, liberating fructose
4. Glucan binding proteins
Three GTF (Glycosyltransferase) enzymes of S. mutans:
1. GtfB (Gtfl)- water insoluble glucan, alpha 1,3 linked
2. GtfC (GtfSl)- both water insoluble glucan alpha 1,3 linked and water soluble alpha 1,6-linked glucose
3. GtfD (GtfS)- water soluble alpha 1,6-linked glucose
Probiotics used to treat dental caries:
1. S. Oligofermentans- metabolizes lactic acid
2. S. Australis- raises plaque pH
3. S. Gordonii- Produces protease that degrades CSP
Glucan (EPS) production by S. mutans requires ____
Bacterial species most commonly associated with Periodontal Disease:
1. P. Gingivalis (Porphyromonas Gingivalis)
2. Tannerella Forsythia
3. Treponema Denticola
(All anaerobes, all part of Socransky's Red Complex)
1. Gram stain?
2. Oxygen Tolerance?
3. What does it ferment?
4. Why is it a keystone pathogen in periodontal disease?
2. Obligate anaerobic
3. Amino acid (not sugar)
4. Causes disbiosis (inhibits host immune response, allowing bacteria to take over)