title: SigF controls carotenoid pigment production and affects transformation efficiency and hydrogen peroxide sensitivity in Mycobacterium smegmatis.
abstract: Carotenoids are complex lipids that are known for acting against photodynamic injury and free radicals. We demonstrate here that sigma(F) is required for carotenoid pigment production in Mycobacterium smegmatis. We further show that a sigF mutant exhibits a transformation efficiency 10(4)-fold higher than that of the parental strain, suggesting that sigma(F) regulates the production of components affecting cell wall permeability. In addition, a sigF mutant showed an increased sensitivity to hydrogen peroxide. An in silico search of the M. smegmatis genome identified a number of SigF consensus sites, including sites upstream of the carotenoid synthesis locus, which explains its SigF regulation.
authors.affiliation: Dipartimento di Biologia, Universitá di Padova, Padua, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Provvedi
authors.forename: Dana
authors.initials: D
authors.lastname: Kocíncová
authors.forename: Valentina
authors.initials: V
authors.lastname: Donà
authors.forename: Daniel
authors.initials: D
authors.lastname: Euphrasie
authors.forename: Mamadou
authors.initials: M
authors.lastname: Daffé
authors.forename: Gilles
authors.initials: G
authors.lastname: Etienne
authors.forename: Riccardo
authors.initials: R
authors.lastname: Manganelli
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Reyrat
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D002338:Carotenoids / Q000096:biosynthesis*; D004251:DNA Transposable Elements / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D016254:Mutagenesis, Insertional; D020102:Mycobacterium smegmatis / Q000187:drug effects* / Q000378:metabolism*; D016877:Oxidants / Q000494:pharmacology*; D012808:Sigma Factor / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; C064971:FliA protein, Bacteria; D016877:Oxidants; D012808:Sigma Factor; D002338:Carotenoids; D006861:Hydrogen Peroxide