Recent insights into the general stress response regulatory network in Escherichia coli.

Many bacterial species exhibit a general stress response that can be induced by numerous very different stress conditions and, phenotypically, renders the cells broadly stress resistant. In Escherichia coli ,t his response is dependent on the s S (RpoS) subunit of RNA polymerase. s S is a close relative of the vegetative sigma factor s 70 (RpoD) and recognizes very similar promoter sequences. In recent years, significant progress has been made with respect to elucidating (i) the molecular mechanisms that control the cellular s S level, which include translational regulation as well as intricate control of s S proteolysis, and (ii) the molecular function of s S as a transcription initiation factor, where a number of s S -dependent promoters have been studied in great detail, and the mechanisms that generate s S selectivity are