title: Magnetococcus marinus gen. nov., sp. nov., a marine, magnetotactic bacterium that represents a novel lineage (Magnetococcaceae fam. nov., Magnetococcales ord. nov.) at the base of the Alphaproteobacteria.
abstract: Magnetotactic bacteria are a morphologically, metabolically and phylogenetically disparate array of bacteria united by the ability to biomineralize membrane-encased, single-magnetic-domain mineral crystals (magnetosomes) that cause the cell to orientate along the Earth's geomagnetic field. The most commonly observed type of magnetotactic bacteria is the ubiquitous magnetotactic cocci, which comprise their own phylogenetic group. Strain MC-1(T), a member of this group, was isolated from water collected from the oxic-anoxic interface of the Pettaquamscutt Estuary in Rhode Island, USA, and cultivated in axenic culture. Cells of strain MC-1(T) are roughly spherical, with two sheathed bundles of flagella at a single pole (bilophotrichous). Strain MC-1(T) uses polar magnetotaxis, and has a single chain of magnetite crystals per cell. Cells grow chemolithoautotrophically with thiosulfate or sulfide as the electron donors, and chemo-organoheterotrophically on acetate. During autotrophic growth, strain MC-1(T) relies on the reductive tricarboxylic acid cycle for CO2 fixation. The DNA G+C content is 54.2 mol%. The new genus and species Magnetococcus marinus gen. nov., sp. nov. are proposed to accommodate strain MC-1(T) ( = ATCC BAA-1437(T)  = JCM 17883(T)), which is nominated as the type strain of Magnetococcus marinus. A new order (Magnetococcales ord. nov.) and family (Magnetococcaceae fam. nov.) are proposed for the reception of Magnetococcus and related magnetotactic cocci, which are provisionally included in the Alphaproteobacteria as the most basal known lineage of this class.
authors.affiliation: Department of Biological Sciences, University of Nevada at Las Vegas, 4505 Maryland Parkway, Las Vegas, NV 89154, USA.
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Bazylinski
authors.affiliation: School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Williams
authors.affiliation: Laboratoire de Bioénergétique Cellulaire, UMR 6191, CEA Cadarache, DSV, IBEB, Saint-Paul-lez-Durance, F-13108, France.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Lefèvre
authors.affiliation: Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Berg
authors.affiliation: Department of Marine Sciences, University of Georgia, Athens, GA 30602, USA.|Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802, USA.
authors.forename: Chuanlun L
authors.initials: CL
authors.lastname: Zhang
authors.affiliation: Division of Translational Medicine, Wadsworth Center, New York State Department of Health, PO Box 509, Albany, NY 12201, USA.
authors.forename: Samuel S
authors.initials: SS
authors.lastname: Bowser
authors.affiliation: Pioneer Hi-Bred, Int'l Inc., 7300 NW 62nd Avenue, Johnston, IA 50131-1004, USA.
authors.forename: Annette J
authors.initials: AJ
authors.lastname: Dean
authors.affiliation: Department of Microbiology, College of Biological Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
authors.forename: Terrence J
authors.initials: TJ
authors.lastname: Beveridge
mesh_terms: D020561:Alphaproteobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D015373:Bacterial Typing Techniques; D001482:Base Composition; D002952:Citric Acid Cycle; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis; D055944:Magnetosomes / Q000382:microbiology; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012237:Rhode Island; D012623:Seawater / Q000382:microbiology; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D005227:Fatty Acids; D012336:RNA, Ribosomal, 16S