Purification and characterization of alpha-N-acetylgalactosaminidase from Clostridium perfringens

alpha -N-Acetylgalactosaminidase from Clostridium perfringens is an exoglyc osidase that degrades the human blood type A epitope, A highly purified pre paration of alpha -N-acetylgalactosaminidase was obtained from C. perfringe ns by salt precipitation, gel filtration, ion-exchange chromatography, chro matofocusing, and high-pressure liquid chromatography, The final preparatio n was homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophore sis, with a molecular mass of 72.1 kDa. The enzyme was highly selective for terminal N-acetyl-alpha -D-galactosamine residues. No other substantial gl ycosidase activities, specifically neuraminidase, were detected. The pH opt imum of the enzyme was between 6.5 and 7.0, and activity was unaffected by ionic strength, No protease activity was detected and enzyme activity was s table at 4 degreesC for 12 months. ELISA experiments demonstrated activity against blood type A epitope.