What surface structures facilitate adhesion among oral bacteria and influence coaggregation?

What surface structures facilitate adhesion among oral bacteria and influence coaggregation?

• A. Capsules and exopolysaccharides mediate adhesion and coaggregation.
• B. Fimbriae and various adhesins on bacterial surfaces mediate adhesion and coaggregation.
• C. Flagella-driven motility is the primary driver of coaggregation.
• D. Endospores prevent adhesion.

Answer: (B)

Adhesion among oral bacteria and coaggregation are driven by fimbriae (pili) and surface adhesins. Fimbriae are hair-like projections that extend from the cell and recognize receptors on neighboring bacteria, promoting close contact and specific pairing essential for coaggregation. Adhesins are specialized surface proteins that bind to complementary ligands on other species, providing the molecular interactions that link different bacteria into mixed communities. Capsules and exopolysaccharides can help with general adhesion to surfaces and contribute to the biofilm matrix, but they are less specific for interbacterial binding than fimbrial adhesins. Flagella mainly enable movement rather than establishing the stable, specific contacts required for coaggregation, and endospores are not involved in mediating adhesion in the oral environment.