RpoS-Regulated Genes of<i>Escherichia coli</i>Identified by Random<i>lacZ</i>Fusion Mutagenesis

ABSTRACTRpoS is a conserved alternative sigma factor that regulates the expression of many stress response genes inEscherichia coli. The RpoS regulon is large but has not yet been completely characterized. In this study, we report the identification of over 100 RpoS-dependent fusions in a genetic screen based on the differential expression of an operon-lacZfusion bank inrpoSmutant and wild-type backgrounds. Forty-eight independent gene fusions were identified, including several in well-characterized RpoS-regulated genes, such asosmY,katE, andotsA. Many of the other fusions mapped to genes of unknown function or to genes that were not previously known to be under RpoS control. Based on the homology to other known bacterial genes, some of the RpoS-regulated genes of unknown functions are likely important in nutrient scavenging.

RpoS-Regulated Genes ofEscherichia coliIdentified by RandomlacZFusion Mutagenesis Journal Articles