Digestion of N-acetylmannosamine and n-acetylneuraminic acid by human oral bacteria.

Abstract

AMIR et al.1 suggested that terminal, non-reducing residues of N-acetylneuraminic acid in salivary mucoproteins act as inducer molecules to oral bacteria, producing sequentially a neuraminidase and later an aldolase which cleaves N-acetylneuraminic acid to N-acetylmannosamine and pyruvic acid. Leach2 showed that bacterial enzyme systems, which correspond in their action with those two enzymes, are present in human saliva, and neuraminidase activity has been found3 in the supernatant fluids of mixed cultures of human oral bacteria from subgingival detritus. In a previous publication1 we reported the induction in human oral bacteria of an enzyme which digests N-acetylmannosamine in a reaction which may be regarded as the direct consequence of the sequential degradation of salivary mucoproteins. We wish to report a similar digestion of N-acetylmannosamine by bacteria present in dental scrapings (plaque, calculus, etc.) and the isolation from human saliva of pure bacterial cultures which degrade. N-acetylneuraminic acid and N-acetylmannosamine.