How are glycosidases distributed between different species of oral bacteria?

How are glycosidases distributed between different species of oral bacteria?

• A. Evenly
• B. Uniform across genus
• C. Randomly distributed across species
• D. Concentrated in a few species

Answer: (C)

Glycosidases in oral bacteria are not found in a uniform pattern across species. Different bacteria encounter different substrates in the oral environment—from host mucins to dietary polysaccharides—so having specific glycosidases provides a selective advantage to particular species in particular niches. Addition to this, gene gain and loss, as well as horizontal gene transfer among members of the oral biofilm, shape which species carry which glycosidases. Because these forces act differently across the diverse species in dental plaque, the presence of glycosidase enzymes ends up patchy and varies from one species to another, giving a distribution that looks random rather than evenly spread or uniform within a genus.

Glycosidases in oral bacteria are not found in a uniform pattern across species. Different bacteria encounter different substrates in the oral environment—from host mucins to dietary polysaccharides—so having specific glycosidases provides a selective advantage to particular species in particular niches. Addition to this, gene gain and loss, as well as horizontal gene transfer among members of the oral biofilm, shape which species carry which glycosidases. Because these forces act differently across the diverse species in dental plaque, the presence of glycosidase enzymes ends up patchy and varies from one species to another, giving a distribution that looks random rather than evenly spread or uniform within a genus.