Bacteriocins are used by different bacterial species as __________ to either hold onto or invade a niche colonized by other microbes. Many oral streptococci contain bacteriocins, including Streptococcus mutans, which is used to combat other species present in the oral cavity.

• A. Virulence factors
• B. Resistance factors
• C. Colonization factors
• D. Nutrient acquisition factors

Answer: (C)

Bacteriocins help bacteria shape who gets to stay in a shared space by suppressing competitors, giving the producer an edge in colonizing a niche. In the oral cavity, streptococci like Streptococcus mutans use these antimicrobial peptides to inhibit neighboring species, aiding their attachment and persistence on tooth surfaces and within dental biofilms. This is about establishing and maintaining a presence in a niche, not directly causing host damage, resisting external agents, or grabbing nutrients. So the best way to describe their role is as colonization factors.