Multiple forms of lysyl-transfer ribonucleic acid synthetase in Escherichia coli
Multiple forms of lysyl-transfer ribonucleic acid synthetase in Escherichia coli
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大肠杆菌中多种形式的赖氨酰转移核糖核酸合成酶
DOI：
10.1128/jb.146.1.345-351.1981
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发表时间：
1981
影响因子：
3.2
通讯作者：
Neidhardt
中科院分区：
文献类型：
--
作者：
N. Irvin;Hirshfield;L. Philip;Bloch;Ruth A. Van;Bogelen;And;C. Frederick;Neidhardt
对大肠杆菌全细胞裂解物进行双向聚丙烯酰胺凝胶电泳，鉴定出赖基转移核糖核酸合成酶（EC 6.1.1.6）为4个多肽点。通过部分纯化酶制剂的迁移、多肽图谱、突变体分析以及不同生长条件下斑点强度与酶水平变化的相关性进行鉴定。在37℃葡萄糖培养基中生长的野生型细胞，酶主要表现为两个斑点（斑点I和斑点III）。在46℃下生长，在丙氨酸或甘氨酸-l -亮氨酸存在下生长，或突变缺乏s -腺苷蛋氨酸合成酶（metK）的菌株生长，大大增加了另外两个斑点（斑点II和IV）的合成。在赖氨酸转移核糖核酸合成酶突变体中，多肽I和III改变了等电点，而多肽II和IV没有改变。这些数据表明，体内存在多种形式的赖氨酸转移核糖核酸合成酶，它们可能由多个基因编码。
Lysyl-transfer ribonucleic acid synthetase (EC 6.1.1.6) was identified as four polypeptide spots after two-dimensional polyacrylamide gel electrophoresis of whole-cell lysates of Escherichia coli. Identification was made by migration with partially purified enzyme preparations, by peptide map patterns, by mutant analysis, and by correlation of spot intensities with changes in enzyme levels under different growth conditions. Wild-type cells growing at 37 degrees C in glucose minimal medium displayed the enzyme predominantly as two spots (spots I and III). Growth at 46 degrees C, growth in the presence of alanine or glycyl-L-leucine, or growth of a strain with a mutational deficiency in S-adenosylmethionine synthetase (metK) greatly increased the synthesis of two other spots (spots II and IV). Polypeptides I and III, but not polypeptides II and IV, had altered isoelectric points in a lysyl-transfer ribonucleic acid synthetase mutant. These data suggest that multiple forms of lysyl-transfer ribonucleic acid synthetase exist in vivo and that they may be encoded by more than one gene.