title: Small RNAs and small proteins involved in resistance to cell envelope stress and acid shock in Escherichia coli: analysis of a bar-coded mutant collection.
abstract: More than 80 small regulatory RNAs (sRNAs) and 60 proteins of 16 to 50 amino acids (small proteins) are encoded in the Escherichia coli genome. The vast majority of the corresponding genes have no known function. We screened 125 DNA bar-coded mutants to identify novel cell envelope stress and acute acid shock phenotypes associated with deletions of genes coding for sRNAs and small proteins. Nine deletion mutants (ssrA, micA, ybaM, ryeF, yqcG, sroH, ybhT, yobF, and glmY) were sensitive to cell envelope stress and two were resistant (rybB and blr). Deletion mutants of genes coding for four small proteins (yqgB, mgrB, yobF, and yceO) were sensitive to acute acid stress. We confirmed each of these phenotypes in one-on-one competition assays against otherwise-wild-type lacZ mutant cells. A more detailed investigation of the SsrA phenotype suggests that ribosome release is critical for resistance to cell envelope stress. The bar-coded deletion collection we generated can be screened for sensitivity or resistance to virtually any stress condition.
authors.affiliation: Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892-5430, USA.
authors.forename: Errett C
authors.initials: EC
authors.lastname: Hobbs
authors.forename: Jillian L
authors.initials: JL
authors.lastname: Astarita
authors.forename: Gisela
authors.initials: G
authors.lastname: Storz
mesh_terms: D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects / Q000235:genetics; D005816:Genetic Complementation Test; D006851:Hydrochloric Acid / Q000494:pharmacology*; D007613:Kanamycin Resistance / Q000502:physiology; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D012329:RNA, Bacterial / Q000235:genetics / Q000502:physiology*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology*; D013312:Stress, Physiological
chemical_list: D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D012967:Sodium Dodecyl Sulfate; D006851:Hydrochloric Acid