Sequencing, mutational analysis, and transcriptional regulation of theEscherichia coli htrBgene

摘要

SummaryTheEscherichia coli htrBgene was originally discovered because its insertional inactivation led to an exquisitely temperature‐sensitive phenotype in rich media, i.e. the ability to form colonies at temperatures below 32°C, but not above 33°C. ThehtrBgene has been sequenced. It can potentially code for two proteins, withMrvalues of 35407 Da and 8669 Da, that are encoded by overlapping, divergent open reading frames. Our data are consistent with the 35407 Da protein being HtrB. Northern blot analysis clearly shows that the monocistronichtrBmessage is not under heat‐shock regulation. We have also sequenced the flanking DNA and have discovered a new gene, designatedorf39.9, located immediately adjacent tohtrB, but divergently transc