来自极端嗜盐菌——深红嗜盐杆菌的5-S RNA.蛋白质复合物。纯化与特性鉴定。

The 5-S RNA . protein complex from an extreme halophile, Halobacterium cutirubrum. Purification and characterization.

作者信息

Smith N, Matheson A T, Yaguchi M, Willick G E, Nazar R N

出版信息

Eur J Biochem. 1978 Sep 1;89(2):501-9. doi: 10.1111/j.1432-1033.1978.tb12554.x.

DOI:10.1111/j.1432-1033.1978.tb12554.x

Abstract

A 5-S RNA . protein complex has been isolated from the 50-S ribosomal subunit of an extreme halophile, Halobacterium cutirubrum. The 50-S ribosomal subunit from the extreme halophile requires 3.4 M K+ and 100 mM Mg2+ for stability. However, if the high K+ concentration is maintained but the Mg2+ concentration lowered to 0.3 mM, the 5-S RNA . protein complex is selectively extracted from the subunit. After being purified on an Agarose 0.5-m column the complex had a molecular weight of about 80000 and contained 5-S RNA and two proteins, HL13 and HL19, with molecular weights (by sedimentation equilibrium) of 18700 and 18000, respectively. No ATPase or GTPase activity could be detected in the 5-S RNA . protein complex. The amino acid composition and electrophoretic mobility on polyacrylamide gels indicated both proteins were much more acidic than the equivalent from Escherichia coli or Bacillus stearothermophilus. Partial amino acid sequence data suggest HL13 is homologous to EL18 and HL19 to EL5.

摘要

已从嗜盐菌（Halobacterium cutirubrum）的50-S核糖体亚基中分离出一种5-S RNA.蛋白质复合物。嗜盐菌的50-S核糖体亚基需要3.4 M K⁺和100 mM Mg²⁺来维持稳定性。然而，如果保持高K⁺浓度，但将Mg²⁺浓度降至0.3 mM，5-S RNA.蛋白质复合物会从亚基中被选择性提取出来。在0.5-m琼脂糖柱上纯化后，该复合物的分子量约为80000，包含5-S RNA和两种蛋白质，HL13和HL19，其分子量（通过沉降平衡法测定）分别为18700和18000。在5-S RNA.蛋白质复合物中未检测到ATP酶或GTP酶活性。氨基酸组成和在聚丙烯酰胺凝胶上的电泳迁移率表明，这两种蛋白质比来自大肠杆菌或嗜热脂肪芽孢杆菌的相应蛋白质酸性更强。部分氨基酸序列数据表明HL13与EL18同源，HL19与EL5同源。