【摘要】 酿酒酵母 Cu2 +抗株 YND2 1经含一定浓度的氯化铜培养基诱导培养后 ,收集菌体 ,破碎细胞 ,离心后Sephadex G-50和 DEAE-cellulose柱层析分离可获得三种铜结合蛋白 DE-1 ,DE-2 ,DE-3 .DE-1脱盐后 ( G-1 )经鉴定具有金属硫蛋白的特性 :表观分子量约为 1 8k D;每分子蛋白含 2 0个巯基 ,结合 1 1个铜原子 ;氨基酸组成中富含半胱氨酸 ( 1 8% )、碱性和酸性氨基酸 ,而酪氨酸和蛋氨酸含量极微 ;等电点为 5.1 . G-1经 SDS-PAGE和等电点聚焦电泳分析证明是均一的 ,与有关文献报导基本相符 .更多还原

【Abstract】 Three proteins DE 1,DE 2 and DE 3 were produced from the Cu 2+ resistant strain YND21 of Saccharomyces cerevisiae induced with CuCl 2 and isolated by means of Sephadex G 50 and DEAE cellulose column chromatography. The purified Cu binding protein G 1 has the characteristics of metallothioneins:(1) low molecular weight (apparent molecular weight 18000D), (2) high Cu and SH content(each molecule contains 20 thiol groups and combines with 11 copper atoms),(3) amino acid composition rich in cysteine(18%), basic and acidic amino acids but almost free from aromatic amino acids (Tyr)and Met, (4) isoelectric point about 5.13. Purified protein G 1 was shown to be homogeneous by analysis of SDS PAGE and IEF, and largely consistent with the metallothioneins reported.更多还原