title: Growth of magnetotactic sulfate-reducing bacteria in oxygen concentration gradient medium.
abstract: Although dissimilatory sulfate-reducing bacteria (SRB) are generally described as strictly anaerobic organisms with regard to growth, several reports have shown that some SRB, particularly Desulfovibrio species, are quite resistant to O2. For example, SRB remain viable in many aerobic environments while some even reduce O2to H2O. However, reproducible aerobic growth of SRB has not been unequivocally documented. Desulfovibrio magneticus is a SRB that is also a magnetotactic bacterium (MTB). MTB biomineralize magnetosomes which are intracellular, membrane-bounded, magnetic iron mineral crystals. The ability of D. magneticus to grow aerobically in several different media under air where an O2concentration gradient formed, or under O2-free N2gas was tested. Under air, cells grew as a microaerophilic band of cells at the oxic-anoxic interface in media lacking sulfate. These results show that D. magneticus is capable of aerobic growth with O2as a terminal electron acceptor. This is the first report of consistent, reproducible aerobic growth of SRB. This finding is critical in determining important ecological roles SRB play in the environment. Interestingly, the crystal structure of the magnetite crystals of D. magneticus grown under microaerobic conditions showed significant differences compared with those produced anaerobically providing more evidence that environmental parameters influence magnetosome formation.
authors.affiliation: CNRS/CEA/Aix-Marseille Université UMR7265 Institut de biosciences et biotechnologies Laboratoire de Bioénergétique Cellulaire, Saint Paul lez Durance, 13108, France.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Lefèvre
authors.affiliation: School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, NV, 89154-4004, USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Howse
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA.
authors.forename: Marian L
authors.initials: ML
authors.lastname: Schmidt
authors.affiliation: CNRS/CEA/Aix-Marseille Université UMR7265 Institut de biosciences et biotechnologies Laboratoire de Bioénergétique Cellulaire, Saint Paul lez Durance, 13108, France.
authors.forename: Monique
authors.initials: M
authors.lastname: Sabaty
authors.affiliation: Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Universités, Université Pierre et Marie Curie, UMR 7590 CNRS, Institut de Recherche pour le Développement UMR 206, Museum National d'Histoire Naturelle, Paris Cedex 05, 75252, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Menguy
authors.affiliation: School of Marine Science and Policy, University of Delaware, 700 Pilottown Rd. Lewes, DE, 19958, USA.
authors.forename: George W
authors.initials: GW
authors.lastname: Luther
authors.affiliation: School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, NV, 89154-4004, USA.
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Bazylinski
mesh_terms: D000332:Aerobiosis; D003901:Desulfovibrio / Q000254:growth & development* / Q000378:metabolism*; D055944:Magnetosomes / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism*
chemical_list: D013431:Sulfates; D009584:Nitrogen; D010100:Oxygen