Construction and Analysis of HybridEscherichia coli-Bacillus subtilis dnaK Genes
Construction and Analysis of HybridEscherichia coli-Bacillus subtilis dnaK Genes
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DOI：
10.1128/jb.181.6.1971-1974.1999
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发表时间：
1999-03
影响因子：
3.2
通讯作者：
A. Mogk;B. Bukau;Rolf Lutz;W. Schumann
中科院分区：
文献类型：
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作者：
A. Mogk;B. Bukau;Rolf Lutz;W. Schumann
DnaK分子伴侣由N端ATP酶结构域、中心底物结合结构域和C端功能未知的结构域组成。由于枯草芽孢杆菌dnaK不能补充大肠杆菌dnaK无效突变体，我们进行了结构域元件交换实验，以确定负责这一发现的区域。结果发现，B。subtilis DnaK蛋白需要大约正常量的辅伴侣DnaJ才能在E.杆菌ATP酶结构域和底物结合结构域形成物种特异性功能单元，而C-末端结构域虽然不太保守，但可交换。E. coliDnaK既不影响λ噬菌体在高温下的互补生长，也不影响λ噬菌体的增殖，但却能抑制λ噬菌体的降解。
ABSTRACT The highly conserved DnaK chaperones consist of an N-terminal ATPase domain, a central substrate-binding domain, and a C-terminal domain whose function is not known. Since Bacillus subtilis dnaK was not able to complement an Escherichia coli dnaK null mutant, we performed domain element swap experiments to identify the regions responsible for this finding. It turned out that the B. subtilis DnaK protein needed approximately normal amounts of the cochaperone DnaJ to be functional in E. coli. The ATPase domain and the substrate-binding domain form a species-specific functional unit, while the C-terminal domains, although less conserved, are exchangeable. Deletion of the C-terminal domain in E. coli DnaK affected neither complementation of growth at high temperatures nor propagation of phage λ but abolished degradation of ς32.