Purification and characterization of beta-N-acetylhexosaminidases and beta-galactosidase from Streptococcus 6646 K.
Three beta-N-acetylhexosaminidases [EC 3.2.1.52] and one beta-galactosidase [EC 3.2.1.23] were purified from the culture filtrate of streptococcus 6646 group K by a combination of column chromatographies on p-aminophenyl beta-D-thiogalactopyranoside-substituted Sepharose and N-(paminophenyl)oxamic acid-substituted Sepharose. These beta-N-acetylhexosaminidases showed optimal activities between pH 5.0 and 5.5 and could hydrolyze synthetic and glycopeptidic substrates. Glycolipids such as GM2, asialo-GM2, and globoside I were no susceptible to these beta-hexosaminidases. beta-Galactosidase, which was purified more than 11,000-fold, had a substrate specificity rather similar to that of beta-galactosidase from E. coli. This enzyme was inhibited by EDTA and activated by Mn2+, Ca2+, and Mg2+. Problems pertinent to the application of affinity chromatography to the purification of glycosidases are also discussed.
D002413:Cations, Divalent / Q000494:pharmacology; D002846:Chromatography, Affinity; D004492:Edetic Acid / Q000494:pharmacology; D005696:Galactosidases / Q000302:isolation & purification / Q000378:metabolism*; D006017:Glycolipids / Q000378:metabolism; D006020:Glycopeptides / Q000378:metabolism; D006596:Hexosaminidases / Q000302:isolation & purification / Q000378:metabolism*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D013291:Streptococcus / Q000201:enzymology*
D002413:Cations, Divalent; D006017:Glycolipids; D006020:Glycopeptides; D004492:Edetic Acid; D005696:Galactosidases; D006596:Hexosaminidases