Kanaya S, Crouch R J
J Biol Chem. 1983 Jan 25;258(2):1276-81.
The gene for Escherichia coli ribonuclease H has been studied by use of a plasmid which contains a segment of the E. coli chromosome. The genomic DNA was subcloned from pLC28-22 to pBR322 by use of various restriction enzymes. Such subcloning limited the RNase H gene to a piece of DNA no longer than 760 base pairs. Cells bearing plasmids containing the RNase H gene produce as much as 10-15 times the normal amount of RNase H without any drastic effect on maintenance of the plasmid or cell growth. DNA sequence analysis has permitted the prediction of a protein whose molecular weight is 17,559 (155 amino acid residues). The predicted sequence was confirmed by amino acid analysis, NH2-terminal amino acid sequence, and size determination of highly purified RNase H.
利用一种含有大肠杆菌染色体片段的质粒对大肠杆菌核糖核酸酶H基因进行了研究。通过使用各种限制性内切酶，将基因组DNA从pLC28 - 22亚克隆到pBR322。这种亚克隆将核糖核酸酶H基因限制在一段不超过760个碱基对的DNA片段上。携带含有核糖核酸酶H基因质粒的细胞产生的核糖核酸酶H量高达正常量的10 - 15倍，而对质粒的维持或细胞生长没有任何显著影响。DNA序列分析使得能够预测出一种分子量为17559（155个氨基酸残基）的蛋白质。通过氨基酸分析、氨基末端氨基酸序列分析以及高度纯化的核糖核酸酶H的大小测定，证实了预测的序列。
