New members of theEscherichia coliσ^Eregulon identified by a two-plasmid system

Abstract

A previously established method, based on a two-plasmid system, was used to identify promoters recognized by RNA polymerase containing the extracytoplasmic stress response sigma factor sigmaE in Escherichia coli. In addition to previously identified rpoE-dependent promoters, 11 new promoters potentially directing the expression of 15 genes were identified that were active only after over-expression of rpoE. The promoters were confirmed and transcriptional start points of the promoters were determined by primer extension analysis and S1-nuclease mapping. All the promoters contained sequences similar to the consensus sequence of rpoE-dependent promoters. The new rpoE-dependent promoters governed expression of genes encoding proteins involved in primary metabolism (fusA, tufA, recR), phospholipid and lipopolysaccharide biosynthesis (psd, lpxP), signal transduction (sixA), proposed inner or outer membrane proteins (bacA, sbmA, smpA, yeaY), and proteins with unknown function (ybaB, yaiW, yiiS, yiiT, yfeY).

The BAM complex subunit BamE (SmpA) is required for membrane integrity, stalk growth and normal levels of outer membrane β-barrel proteins in Caulobacter crescentus

“…The lipoproteins of the E. coli BAM complex are transcriptionally regulated by s E (Dartigalongue et al, 2001;Kabir et al, 2005;Lewis et al, 2008;Rezuchova et al, 2003), an extracytoplasmic function (ECF) sigma factor that directs the transcription of chaperones, assembly factors and proteases to restore homeostasis after envelope stress . The Caulobacter genome encodes 13 ECF sigma factors (Nierman et al, 2001), and it is currently unclear which of them perform functions analogous to E. coli s E (Alvarez-Martinez et al, 2006.…”

Large mutational target size for rapid emergence of bacterial persistence

“…VisC is a predicted oxidoreductase with an FAD/NAD(P)-binding domain; however, deletion of visC has been found to have no effect on aerobic respiration (25). The gene products of yacC and yiiS have no assigned function, although, yiiS has been identified as a member of the sigma E regulon (26). Further experimentation is required to characterize the role of these genes in persistence.…”

Cell lysis directed by σ E in early stationary phase and effect of induction of the rpoE gene on global gene expression in Escherichia coli

“…Several s E regulon genes, including htrA and fkpA, which encode a periplasmic serine protease (Lipinska et al, 1988(Lipinska et al, , 1989Strauch et al, 1989) and a periplasmic peptidyl-prolyl isomerase (Danese & Silhavy, 1997), respectively, have been well characterized (Ishihama, 1999;. Recently, molecular genetic approaches to search for s E regulon genes have been performed (Dartigalongue et al, 2001b;Rezuchova et al, 2003), increasing the number to 58 genes.…”