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.