title: Rapid procedures for determination of endo-N-acetyl-alpha-D-galactosaminidase in Clostridium perfringens, and of the substrate specificity of exo-beta-D-galactosidases.
abstract: Culture fluid of Clostridium perfringens hydrolyzed the synthetic, chromogenic substrates beta-Gal-(1 leads to 3)-alpha-GalNAc-1 leads to OPh and beta-Gal-(1 leads to 3)-alpha-GalNAc-1 leads to OC6H4-NO2-o or -p to beta-Gal-(1 leads to 3)-GalNAc and the aglycon. Such assays facilitated the characterization and purification of this endo-N-acetyl-alpha-D-galactosaminidase activity. This activity was purified 1200-fold by fractionation with ammonium sulfate and chromatography on columns of Sephadex-G200, DEAE-Sephadex, and hydroxylapatite. The final preparation showed activity over a broad range of pH, with an optimum at 9.0, but less-pure material had two pH optima, 4.0 and 9.0. Another assay method, which employed the synthetic, chromogenic substrates beta-Gal-(1 leads to 3)-beta-GlcNAc-1 leads to OC6H4NO2-p, beta-Gal-(1 leads to 4)-beta GlcNAc-1 leads to OC6H4NO2-p, and beta-Gal-(1 leads to 6)-beta-GlcNAc-1 leads to OC6H4NO2-p, was developed for the rapid identification of the linkage specificity of exo-beta-D-galactosidases from any source via a coupled reaction with N-acetyl-beta-D-hexosaminidase.
mesh_terms: D000116:Acetylgalactosamine / Q000302:isolation & purification / Q000378:metabolism; D003016:Clostridium perfringens / Q000201:enzymology*; D005696:Galactosidases / Q000378:metabolism*; D006596:Hexosaminidases / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007700:Kinetics; D013053:Spectrophotometry / Q000379:methods; D013379:Substrate Specificity; D048809:alpha-N-Acetylgalactosaminidase; D001616:beta-Galactosidase / Q000378:metabolism*
chemical_list: D007202:Indicators and Reagents; D005696:Galactosidases; D006596:Hexosaminidases; D001616:beta-Galactosidase; D048809:alpha-N-Acetylgalactosaminidase; D000116:Acetylgalactosamine