title: Roles of environmental heme, and menaquinone, in streptococcus agalactiae.
abstract: Most bacteria require iron for growth. However, as it may not be directly available under aerobic conditions, bacteria may use iron-sequestering molecules, such as bacterially encoded siderophores, or heme, which is the major iron source in the animal host. Bacteria may also assimilate heme for purposes other than as an iron source. Once internalised, heme can activate, for example, a heme-dependent catalase and a cytochrome oxidase. In bacterial pathogen Streptococcus agalactiae, heme, in association with exogenous menaquinone, activates a respiratory chain. Respiration has radical effects on carbon metabolism. GBS respiration-grown cells display improved survival in an aerobic environment and greater virulence in a murine septicemia model. GBS might benefit from its ecological niches to capture heme and menaquinone, i.e., from other bacteria when it colonizes host mucosa, or from blood-containing organs during septicemia.
authors.affiliation: Recherches Laitières et Génétique Appliquée, Institut National de la Recherche Agronomique, Bâtiment 222, 78352, Jouy en Josas, France.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Claire
authors.initials: C
authors.lastname: Poyart
authors.forename: Patrick
authors.initials: P
authors.lastname: Trieu-Cuot
authors.forename: Gilles
authors.initials: G
authors.lastname: Lamberet
authors.forename: Alexandra
authors.initials: A
authors.lastname: Gruss
authors.forename: Philippe
authors.initials: P
authors.lastname: Gaudu
mesh_terms: D000818:Animals; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D006418:Heme / Q000378:metabolism*; D009154:Mutation; D051381:Rats; D013290:Streptococcal Infections / Q000382:microbiology / Q000401:mortality; D013292:Streptococcus agalactiae / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D015996:Survival Rate; D014774:Virulence / Q000235:genetics; D024482:Vitamin K 2 / Q000378:metabolism*
chemical_list: D024482:Vitamin K 2; D006418:Heme; D003576:Electron Transport Complex IV