Marshall R C, Gillespie J M
Aust J Biol Sci. 1976 Mar;29(1-2):11-20.
The present paper continues the study of the reduced and S-carboxymethylated high-sulphur proteins from mouse hair. Fractions have been obtained in a substantially purified form by fractional precipitation with ammonium sulphate at pH 6, followed by ion exchange chromatography on cellulose phosphate at pH 2.6. Approximately 80% by weight of the high-sulphur proteins fall into the ultra-high-sulphur category (carboxymethylcysteine content greater than 26 residues per 100 residues), and they cover a molecular weight range of 17000-28000. The components show a remarkable diversity in amino acid composition; for example the contents of arginine and glycine each vary by about 3:1. The remainder of the proteins contain 17-20 residues per 100 residues of carboxymethylcysteine, are smaller in size (molecular weight 11500), and also show great diversity in overall amino acid composition. Molecular weights were determined by chromatography on controlled-pore glass and confirmed by gel filtration on Sephadex G-100 and Sepharose 6B. A comparison of the results suggests that the values obtained should be reliable to within 10%.
本文继续对来自小鼠毛发的还原型和S-羧甲基化高硫蛋白进行研究。通过在pH 6下用硫酸铵分级沉淀，然后在pH 2.6下在磷酸纤维素上进行离子交换色谱，已获得了基本上纯化形式的级分。按重量计，约80%的高硫蛋白属于超高硫类别（每100个残基中羧甲基半胱氨酸含量大于26个残基），其分子量范围为17000 - 28000。这些组分在氨基酸组成上表现出显著的多样性；例如，精氨酸和甘氨酸的含量各自变化约3:1。其余的蛋白质每100个残基中含有17 - 20个羧甲基半胱氨酸残基，尺寸较小（分子量11500），并且在整体氨基酸组成上也表现出很大的多样性。分子量通过在可控孔径玻璃上的色谱法测定，并通过在Sephadex G - 100和Sepharose 6B上的凝胶过滤法进行了确认。结果比较表明，所获得的值在10%以内应该是可靠的。
