Purification and characterization of alginate lyase from marine Vibrio sp. YWA

Extracellular alginate lyase secreted by marine Vibrio sp. YWA, isolated from decayed Laminaria japonica, was purified by a combination of ammonium sulfate precipitation and diethylaminoethyl-Sephacel column chromatography. The results show that the molecular mass of alginate lyase was approximately 62.5 kDa, with an optimal pH and temperature at pH 7.0 and 25 degrees C, respectively. K(m) was approximately 72.73 g/L. The activity of the enzyme was enhanced by EDTA and Zn(2+), but inhibited by Ba(2+). The substrates specificity analysis shows that it was specific for hydrolyzing poly-beta-D-1,4-mannuronate in alginate.