Microbial Ecology Flashcards
Name the 5 biofilm advantages.
- Broader habitat at range for growth
- Efficient nutrient acquisition and metabolism
- Protection from antimicrobial agents and stressors
- Colonization resistance
- Pathogenic mechanisms
______ is a cell density directed inter-cell communication mechanism through which secreted molecules regulate gene expression
Quorum sensing
_____ are bacterial extracellular polysaccharides
exopolymers
_____ and _____ make up the intercellular matrix
exopolymers and salivary glycoproteins
_____ are protein toxins that kill like-species and like-strains.
bacteriocins
_____ must be able to adhere to a biological surface.
Indigenous
Once indigenous species that detach and enter saliva are called _____
transients
Frequent dietary sucrose causes a ______ or ____ of Strep. mutans numbers in plaque.
microbial shift or succession
Subgingival plaque tends to contain ______
motile bacteria
_____ adhere to the pellicle and are the first tooth colonizers.
Facultative streptococci (S. sanguinis, S. oralis)
Most plaque growth occurs through ____ rather than ____
multiplication of bacteria; accretion
Name two secondary plaque colonizers.
Veillonella Gm-, anaerobic cocci
Actinomyces Gm+, facultative or anaerobic
What are the late plaque colonizers?
Gram negative and motile obligate anaerobes
Most subsequent anaerobes are ____ and attach to early colonizers by adhesins on the terminal ends of their ___
fimbriated; fimbria
Supragingival plaque nutrients
sugar intracellular polysaccharide (ICP) extracellular polysaccharide (ECP)
