Purification and Properties of Two Deacetylases Produced by Vibrio alginolyticus H-8.

The Chitinase-producing bacterium Vibrio alginolyticus H-8 isolated from mud of Hamana Lake also produced two deacetylases for (GlcNAc)(2) extracellularly, Deacetylases DA1 and DA2 were purified from crude enzyme by column chromatography on Q-Sepharose FF, Phenyl Sepharose HP, Gigapite, and Superdex 200 HR, The final preparation was homogeneous in SDS-PAGE, The molecular weights were 48,000 and 46,000 for deacetylases DA1 and DA2, respectively, The pIs, optimum pHs, and optimum temperatures for deacetylases DA1 and DA2 were as follows; DA1, pI 3.3, optimum pH 8.5-9.0, optimum temperature 45 degrees C, DA2, pI 3.5, optimum pH 8.0-8.5, optimum temperature 40 degrees C, Both deacetylases were stable at pHs between 7.0 and 11.0 and at temperatures below 40 degrees C, The activities of both enzymes were inhibited by Ag+ and Hg2+. H-1-NMR of the reaction product by deacetylase DA1 for (GlcNAc)(2) showed that the purified deacetylase selectively hydrolyzed the 2-acetamide group at the reducing end of (GlcNAc)(2).