Schmidt A, Schiesswohl M, Völker U, Hecker M, Schumann W
Lehrstuhl für Genetik, Universität Bayreuth, Germany.
J Bacteriol. 1992 Jun;174(12):3993-9. doi: 10.1128/jb.174.12.3993-3999.1992.
Using a gene probe of the Escherichia coli groEL gene, a 1.8-kb HindIII fragment of chromosomal DNA of Bacillus subtilis was cloned. Upstream sequences were isolated as a 3-kb PstI fragment. Sequencing of 2,525 bp revealed two open reading frames in the order groES groEL. Alignment of the GroES and GroEL proteins with those of eight other eubacteria revealed 50 to 65% and 72 to 84% sequence similarity, respectively. Primer extension studies revealed one potential transcription start site preceding the groESL operon (S) which was activated upon temperature upshift. Northern (RNA) analysis led to the detection of two mRNA species of 2.2 and 1.5 kb. RNA dot blot experiments revealed an at least 10-fold increase in the amount of specific mRNA from 0 to 5 min postinduction, remaining at this high level for 10 min and then decreasing. A 9-bp inverted repeat within the 5' leader region of the mRNA might be involved in regulation of the heat shock response. By using PBS1 transduction, the groESL operon was mapped at about 342 degrees.
利用大肠杆菌groEL基因的基因探针,克隆了枯草芽孢杆菌染色体DNA的一个1.8kb HindIII片段。上游序列作为一个3kb PstI片段被分离出来。对2525bp的测序揭示了按照groES groEL顺序排列的两个开放阅读框。将GroES和GroEL蛋白与其他八种真细菌的蛋白进行比对,结果显示序列相似性分别为50%至65%和72%至84%。引物延伸研究揭示了在groESL操纵子(S)之前有一个潜在的转录起始位点,该位点在温度升高时被激活。Northern(RNA)分析检测到了两种大小分别为2.2kb和1.5kb的mRNA。RNA斑点杂交实验显示,诱导后0至5分钟内,特异性mRNA的量至少增加了10倍,在这个高水平维持10分钟后下降。mRNA 5'前导区内的一个9bp反向重复序列可能参与热休克反应的调控。通过使用PBS1转导,groESL操纵子被定位在大约342度处。