Transcriptional analysis of major heat shock genes of Helicobacter pylori

The transcriptional organization and heat inducibility of the major heat sh ock genes hrcA, dnaK, dnaJ, groEL, and hfpG were analyzed on the transcript ional level in Helicobacter pylori strain 69A, The strongly heat-induced dn aK operon was found to be tricistronic, consisting of the genes hrcA, grpE, and dnaK, The dnaJ gene specified one monocistronic mRNA which was also he at inducible. The genes groES and groEL were transcribed as one strongly he at-inducible bicistronic mRNA which exhibited exactly the same induction ki netic as the dnaK operon, Surprisingly, transcription of the monocistronic htpG gene was switched off after heat shock The data presented are discusse d with regard to the different mechanisms regulating expression of heat sho ck genes in H. pylori.