Abstract
A chitosanolytic enzyme was purified from Enterobacter sp. G-1 by fractionation of 30% saturation with ammonium sulfate, isoelectric focusing, and Sephadex G-100 gel chromatography. The purified enzyme showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis, and the molecular mass was estimated to be 50kDa. The enzyme degraded N-acetyl-chitooligosaccharides, glycol chitin, colloidal chitin, and colloidal chitosan (about 80% deacetylated), but did not degrade chitooligosaccharides, colloidal chitosan (100% deacetylated), or Micrococcus lysodeikticus cell walls. It hydrolyzed GlcNAc4-6 and colloidal chitin to GlcNAc2, finally. The main cleavage site with GlcNAc3-6 was the second linkage from the non-reducing end, based on the pattern of pNp-GlcNAc2-5. Colloidal chitosan was hydrolyzed to GlcNAc2 and to similar partially N-acetylated chitooligosaccharides.
