title: [Methanotrophic bacteria in cold seeps of the floodplains of northern rivers].
abstract: Small mud volcanoes (cold seeps), which are common in the floodplains of northern rivers, are a potentially important, although poorly studied sources of atmospheric methane. Field research on the cold seeps of the Mukhrina River (Khanty-Mansiysk Autonomous okrug, Russia) revealed methane fluxes from these structures to be orders of magnitude higher than from equivalent areas of the mid-taiga bogs. Microbial communities developing around the seeps were formed under conditions of high methane concentrations, low temperatures (3-5 degrees C), and near-neutral pH. Molecular identification of methane-oxidizing bacteria from this community by analysis of the pmoA gene encoding particulate methane monooxygenase revealed both type I and type II methanotrophs (classes Gammaproteobacteria and Alphaproteobacteria, respectively), with predomination of type I methanotrophs. Among the latter, microorganisms related to Methylobacterpsychrophilus and Methylobacter tundripaludum, Crenothrix polyspora (a stagnant water dweller), and a number of methanotrophs belonging to unknown taxa were detected. Growth characteristics of two isolates were determined. Methylobactersp. CMS7 exhibited active growth at 4-10 degrees C, while Methylocystis sp. SB12 grew better at 20 degrees C. Experimental results confirmed the major role ofmethanotrophic gammaproteobacteria in controlling the methane emission from cold river seeps.
authors.forename: S É
authors.initials: SÉ
authors.lastname: Belova
authors.forename: I Iu
authors.initials: IIu
authors.lastname: Oshkin
authors.forename: M V
authors.initials: MV
authors.lastname: Glagolev
authors.forename: E D
authors.initials: ED
authors.lastname: Lapshina
authors.forename: Sh Sh
authors.initials: ShSh
authors.lastname: Maksiutov
authors.forename: S N
authors.initials: SN
authors.lastname: Dedysh
mesh_terms: D042082:Methylobacteriaceae / Q000145:classification / Q000302:isolation & purification / Q000502:physiology*; D008772:Methylococcaceae / Q000145:classification / Q000302:isolation & purification / Q000502:physiology*; D042083:Methylocystaceae / Q000145:classification / Q000302:isolation & purification / Q000502:physiology*; D045483:Rivers / Q000382:microbiology*; D012800:Siberia; D014871:Water Microbiology