Amemura-Maekawa J, Watanabe H
Department of Bacteriology, National Institute of Infectious Diseases, Tokyo, Japan.
Gene. 1997 Sep 15;197(1-2):165-8. doi: 10.1016/s0378-1119(97)00257-6.
A 4.4-kb DNA fragment from Legionella pneumophila (Lp) was isolated, which could complement an Escherichia coli (Ec) dnaK ts mutant, HC4102. Nucleotide sequence analysis of the region revealed two complete open reading frames (ORFs) encoding both a predicted DnaK protein of 644 aa and a predicted GrpE protein of 199 aa, and also the 5'-end of the predicted dnaJ gene organized in the order of grpE-dnaK-dnaJ. Consensus heat shock (HS) promoter sequences were identified upstream of the start of both grpE and dnaK transcripts. However, no obvious promoter sequences were detected upstream of dnaJ. The transcription start points of grpE and dnaK were determined by primer extension analysis and the amount of each of the transcripts increased four- to eightfold after HS.
从嗜肺军团菌（Lp）中分离出一个4.4kb的DNA片段，它可以互补大肠杆菌（Ec）的dnaK温度敏感突变体HC4102。对该区域的核苷酸序列分析显示有两个完整的开放阅读框（ORF），分别编码一个预测的644个氨基酸的DnaK蛋白和一个预测的199个氨基酸的GrpE蛋白，并且预测的dnaJ基因的5'端按grpE-dnaK-dnaJ的顺序排列。在grpE和dnaK转录起始上游鉴定出共有热休克（HS）启动子序列。然而，在dnaJ上游未检测到明显的启动子序列。通过引物延伸分析确定了grpE和dnaK的转录起始点，热休克后每种转录本的量增加了4至8倍。
