Degradative enzymes of oral streptococci

Abstract

Members of the Streptococcus sanguis group (SSG) and Streptococcus milleri group (SMG) were screened for their ability to produce glycosidase, arylamidase (peptidase), protease, dextranase and glycosyltransferase activities. Species within each group produced unique patterns of activity. The most commonly produced glycosidases were beta-D-glucosidase, beta-D-galactosidase, N-acetyl-beta-D-glucosaminidase and N-acetyl-beta-D-galactosaminidase and the least commonly produced glycosidase activity was beta-fucosidase with Streptococcus intermedius (SMG) being the only species capable of producing the activity. For arylamidase activity, the most commonly produced type was lysine-arylamidase. Glycosidase and arylamidase activities were localized to particular sub-cellular fractions. alpha-galactosidase was found only in culture supernatant fluids whereas N-acetyl-beta-D-glucosaminidase was found in all fractions; the culture supernatant, cell wall, cell membrane and cytoplasm. No arylamidase activity was seen in culture supernatants. Phe-arg-arylamidase was found only in cytoplasmic fractions whereas val-pro-argarylamidase was found in cell walls, cell membranes and cytoplasmic fraction. Protease activity was measured as the degradation of bovine serum albumin (BSA) and casein. Casein was degraded by a number of strains whereas no species/strains were able to degrade BSA. Streptococcus intermedius, Streptococcus constellatus (SMG), Streptococcus mitior and Streptococcus defectivus (SSG) were the only species that produced hyaluronidase and no species produced chondroitin sulphatase. The groups were also examined for their abilities to produce glycosyltransferase and dextranase. Strep. sanguis, Streptococcus gordonii, Streptococcus mitis and Streptococcus oralis produced glucosyltransferase and, with the exception of the latter species, fructosyltransferase. No species within the SMG was capable of producing either glycosyltransferase.(ABSTRACT TRUNCATED AT 250 WORDS)

Streptococcus australis sp. nov., a novel oral streptococcus.

“…Using fluorescently labelled synthetic compounds, we demonstrated that S. australis was able to produce β-galactosidase, N-acetylglucosaminidase and N-acetylgalactosaminidase, but was unable to produce neuraminidase (Willcox et al, 1995). Demonstration of the production of β-galactosidase and N-acetylglucosaminidase with fluorescently labelled substrates was at odds with the results obtained with Rapid ID32 Strep kits, probably demonstrating the effect of different substrates.…”

“…Within the S. mitis group, the species S. oralis and S. mitis are able to produce glucosyltransferases and S. mitis is able to produce fructosyltransferases. However, S. australis cannot produce either of these activities (Willcox et al, 1995) and this may be another useful distinguishing characteristic for this species.…”

Novel Extracellular x-Prolyl Dipeptidyl-Peptidase (DPP) from Streptococcus gordonii FSS2: an Emerging Subfamily of Viridans Streptococcal x-Prolyl DPPs

“…This use of plasma proteins by oral streptococci as carbon and nitrogen sources would ostensibly benefit growth in the vegetation. Certainly, proteolytic and peptide transport systems for viridans members have been described (1,7,17,18,25,45,54), and it has been shown that small peptides can be imported into S. sanguinis, while those exceeding size limitations would require further hydrolysis by endo-and exopeptidases present on the surface or secreted by these cells (8). One such activity that facilitates these metabolic requirements, a dipeptidyl peptidase (DPP) with Gly-Pro-pNa hydrolyzing activity, has been detected in culture supernatant of S. gordonii (8,19) yet has remained undefined.…”

Inflammatory components of human tear fluid

“…Co., MO, USA) for plasmin like activity. 16 Substrate was dissolved in a minimum (< 20 pl) of dimethylsulphoxide (DMSO) and diluted with 50 m M N-Tris(hydroxymethy1) methyl-2-aminoethane sulphonic acid buffer (pH 7 3 , to final concentration 100 pg/mL. Substrate (100 pL) was mixed with plasmin standard (0.1 mg to 20pg/mL, Sigma Chem.…”