酵母SOD分离纯化及其酶学性质的研究

目的发酵培养Y12 酵母菌分离制备酵母SOD并研究其部分酶学性质。方法用已筛选出的一株Y12 酵母菌对其在优化培养条件下发酵培养得到湿菌体 ,破壁抽提得SOD粗酶液 ,采用硫铵盐析、丙酮沉淀、SephadexG 10 0凝胶过滤和QAE SephadexA 5 0离子交换柱层析 ,分离得到酵母SOD并测定其部分酶学性质。结果Y12 酵母菌SOD产量达 12 6 3u·g-1湿菌体 ,分离得到酵母SOD ,该酶属Cu、Zn SOD ,比活力为 10 73 5u·mg-1,活力回收率为 5 4 1% ,紫外吸收峰在2 5 7 2nm ,分子质量为 32 4 5 6u ,亚基分子质量为 16 2 2 7u。结论此酵母SOD与文献中报道的动物血红细胞Cu、Zn SOD基本相近。

Purification of the SOD from the yeast and studies on its enzymology character

Objective To purify SOD from yeast Y 12 by fermentation and study on its enzymic character.Methods In this experiment,the SOD producing strain-yeast Y 12 was obtained from 9 strains of different yeasts.Its wet weight of cells and production of SOD were all higher under optimal conditions.The SOD from yeast Y 12 by fermentation has been purified by salting out with ammonium sulfate fractionation,acetone precipitation,sephadex G-100 gel filtration and column chromatograph on QAE-sephadex A-50.Results The specific activity of SOD from yeast was estimated as 1073.5 u·mg -1,the yield of the activity was 54.1%,molecular mass was 32 456 u and the molecular mass of enzyme subunit was 16 227 u.It exhibits one absoration maximum in the ultraviolet at 257 nm.Conclusions The results indicate the enzyme is Cu,Zn-SOD.This enzyme is similar to the Cu,Zn-SOD from animal blood erythrocyte in characterization.