Which best describes Veillonella's interactions with other oral bacteria?

• A. Antagonistic
• B. Positive
• C. Detrimental
• D. Null

Answer: (B)

The going-on here is metabolic handoff in the oral biofilm. Veillonella relies on lactate produced by early colonizers like Streptococcus, using that substrate to fuel its own growth. This cross-feeding creates a positive interaction: Veillonella benefits from the lactate supply, and by consuming lactate it can help modulate the local acidity, potentially supporting other members of the community as well. It’s not about inhibiting neighbors or having no effect, so the relationship isn’t antagonistic or null; it’s a cooperative, positive exchange within the biofilm ecosystem.