Purification and characterization of β-1,3-xylanase from a marine bacterium, Vibrio sp XY-214

beta-1,3-Xylanase was purified to gel electrophoretic homogeneity and 83-fold from a cell-free culture fluid of Vibrio sp. XY-214 by ammonium sulfate precipitation and successive chromatographies. The enzyme had a pi of 3.6 and a molecular mass of 52 kDa. The enzyme had the highest level of activity at pH 7.0 and 37 degrees C. The enzyme activity was completely inhibited by Cu2+, Hg2+, and N-bromosuccinimide. The enzyme hydrolyzed beta-1,3-xylan to produce mainly xylotriose and xylobiose but did not act on xylobiose, p-nitrophenyl-beta-D-xyloside, beta-1,4-xylan, beta-1,3-glucan, or carboxymethyl cellulose.