Enzyme activities from eight small-sized oral spirochetes

The purpose of the present investigation was to detect strains of small-sized oral spirochetes isolated from subgingival plaque for protease, peptidase, lipase, glycosidase, phosphatase, hyaluronidase and chondroitinsulfatase activities. The analyses were routinely carried out with cultures in the early stationary phase of growth after 4 days incubation. Both culture media and harvested spirochete cells were examined for the different enzyme activities. The enzymes were assayed by use of the API ZYM system, by p-nitroanilide derivatized peptides, and by hydrolyzing of mucopolysaccharides incorporated in solid bacterial medium. Relatively strong activities of trypsin-like enzymes, mainly bound to the cells, were observed in all strains. Similarly all strains showed acid phosphatases bound to the cells, too. Extracellular hyaluronidase- and chondroitinsulfatase activities were detected qualitatively in all strains after 7 days growth. The activities of the two mucopolysaccharide degrading enzymes almost disappeared after 10 subcultivations. Weak lipase (butyrate), higher lipase (caprylate), and weak phosphoamidase activities were observed in all cell pellets. No glycosidase activities were found. The observations are discussed by regarding the spirochetal enzymes as potential virulence factors for the development of marginal periodontitis.