摘要： 依次经过抽提、分步硫酸铵沉淀、二乙氨乙基纤维素（DEAE Celulose）柱层析，以及聚丙烯酰胺自然胶制备电泳（Preparative PAGE）等分离步骤，从耐热性较强的“白阳”大白菜品种的黄化种苗中，分离和纯化了与耐热性密切相关的一个葡萄糖磷酸变位酶（PGM）同工酶。通过SDS PAGE电泳，纯化的酶样品在29KD处呈现一个显着条带。推测此酶为细胞质来源。我们还同时纯化了与耐热性无关的另一个细胞质PGM同工酶。结果表明，它们只有自然电泳迁移率（电荷量）的不同，而没有明显分子大小的差别。在整个纯化过程中巯基保护试剂的存在对于PGM酶的稳定性至关重要。

关键词: 大白菜, 葡萄糖磷酸变位酶, 同工酶, 蛋白质纯化, 微测序, 耐热基因

Abstract: A heat-tolerance(HT) related phosphoglucomutase isozyme was isolated and purified to homogeneity through a series of steps including ex tract ion,am monium sulphate precipitation ,DEAE-cellulose chromat ography and finally native preparative PAGE.The linear molecular weight of this enzyme was estimated to be about 29 kD by SDS-PAGE.Another PGM isozyme was also purified and was shown to be of the same molecular size.The only difference between the two isozymes appears to be their Rfs on native PAGE.The presence of sulfhydryl reagents was most essential for the stability of PGM during the whole purificat ion processe.

Key words: Chinese cabbage, Phosphoglucomutase isozyme, Protein purification, Microsequencing, Heat tolerance gene

中图分类号: 

• S634.101