title: Iron-corroding methanogen isolated from a crude-oil storage tank.
abstract: Microbiologically influenced corrosion of steel in anaerobic environments has been attributed to hydrogenotrophic microorganisms. A sludge sample collected from the bottom plate of a crude-oil storage tank was used to inoculate a medium containing iron (Fe(0)) granules, which was then incubated anaerobically at 37 degrees C under an N(2)-CO(2) atmosphere to enrich for microorganisms capable of using iron as the sole source of electrons. A methanogen, designated strain KA1, was isolated from the enrichment culture. An analysis of its 16S rRNA gene sequence revealed that strain KA1 is a Methanococcus maripaludis strain. Strain KA1 produced methane and oxidized iron much faster than did the type strain of M. maripaludis, strain JJ(T), which produced methane at a rate expected from the abiotic H(2) production rate from iron. Scanning electron micrographs of iron coupons that had been immersed in either a KA1 culture, a JJ(T) culture, or an aseptic medium showed that only coupons from the KA1 culture had corroded substantially, and these were covered with crystalline deposits that consisted mainly of FeCO(3).
authors.affiliation: NITE Biological Resource Center (NBRC), National Institute of Technology and Evaluation (NITE), 2-5-8 Kazusa-kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Uchiyama
authors.forename: Kimio
authors.initials: K
authors.lastname: Ito
authors.forename: Koji
authors.initials: K
authors.lastname: Mori
authors.forename: Hirohito
authors.initials: H
authors.lastname: Tsurumaru
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Harayama
mesh_terms: D016000:Cluster Analysis; D003343:Corrosion; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D007501:Iron / Q000378:metabolism*; D008697:Methane / Q000378:metabolism*; D017017:Methanococcus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D010578:Petroleum / Q000382:microbiology*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D010578:Petroleum; D012336:RNA, Ribosomal, 16S; D007501:Iron; D008697:Methane