抄録
Purification was conducted on polyvinyl alcohol (PVA) degrading enzyme produced and secreted into the culture medium by Pseudomonas O-3 strain. The enzyme was found to separate into several fractions by ion-exchange chromatography and gel filtration. Among these fractions, a fraction adsorbed to SP-Sephadex C-50 at pH 6.0 was purified to homogeneity by polyacrylamide gel electrophoresis. Some properties of this purified enzyme were examined. Optimum pH and temperature were 9.0 and 40°C, respectively. The enzyme was stable up to 50°C and in a pH range between 5 and 11 at 5°C. The enzyme activity was inhibited by Co2+, Ni2+, EDTA, hydroxylamine and salicylaldoxime. In substrate specificity, this enzyme oxidized several kinds of modified PVA, as well as normal PVA, but did not oxidize other synthetic polymers, such as vinylon, polyacrylamide and polyvinyl acetate. The effect of oxygen on this enzyme was examined, and without oxygen, PVA was not broken down by this enzyme. The molecular weight of this enzyme was estimated by gel filtration on Sephadex G-100 to be approximately 26, 000.
