title: Bacillus subtilis extracytoplasmic function (ECF) sigma factors and defense of the cell envelope.
abstract: Bacillus subtilis provides a model for investigation of the bacterial cell envelope, the first line of defense against environmental threats. Extracytoplasmic function (ECF) sigma factors activate genes that confer resistance to agents that threaten the integrity of the envelope. Although their individual regulons overlap, σ(W) is most closely associated with membrane-active agents, σ(X) with cationic antimicrobial peptide resistance, and σ(V) with resistance to lysozyme. Here, I highlight the role of the σ(M) regulon, which is strongly induced by conditions that impair peptidoglycan synthesis and includes the core pathways of envelope synthesis and cell division, as well as stress-inducible alternative enzymes. Studies of these cell envelope stress responses provide insights into how bacteria acclimate to the presence of antibiotics.
authors.affiliation: Department of Microbiology, Cornell University, Ithaca, NY 14853, USA. Electronic address: jdh9@cornell.edu.
authors.forename: John D
authors.initials: JD
authors.lastname: Helmann
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D018085:Regulon; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D012808:Sigma Factor