title: Deposition of biogenic iron minerals in a methane oxidizing microbial mat.
abstract: The syntrophic community between anaerobic methanotrophic archaea and sulfate reducing bacteria forms thick, black layers within multi-layered microbial mats in chimney-like carbonate concretions of methane seeps located in the Black Sea Crimean shelf. The microbial consortium conducts anaerobic oxidation of methane, which leads to the formation of mainly two biomineral by-products, calcium carbonates and iron sulfides, building up these chimneys. Iron sulfides are generated by the microbial reduction of oxidized sulfur compounds in the microbial mats. Here we show that sulfate reducing bacteria deposit biogenic iron sulfides extra- and intracellularly, the latter in magnetosome-like chains. These chains appear to be stable after cell lysis and tend to attach to cell debris within the microbial mat. The particles may be important nuclei for larger iron sulfide mineral aggregates.
authors.affiliation: Institute of Microbiology and Genetics, Georg-August-University, Grisebachstr. 8, 37077 Göttingen, Germany. cwrede@gwdg.de
authors.forename: Christoph
authors.initials: C
authors.lastname: Wrede
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kokoschka
authors.forename: Anne
authors.initials: A
authors.lastname: Dreier
authors.forename: Christina
authors.initials: C
authors.lastname: Heller
authors.forename: Joachim
authors.initials: J
authors.lastname: Reitner
authors.forename: Michael
authors.initials: M
authors.lastname: Hoppert
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D059038:Black Sea; D002119:Calcium Carbonate / Q000378:metabolism; D019015:Geologic Sediments / Q000382:microbiology*; D007501:Iron / Q000737:chemistry / Q000378:metabolism*; D008697:Methane / Q000378:metabolism*; D059013:Microbial Consortia; D010084:Oxidation-Reduction; D012623:Seawater / Q000382:microbiology*; D013431:Sulfates / Q000378:metabolism; D013440:Sulfides / Q000378:metabolism; D016999:Sulfur-Reducing Bacteria / Q000378:metabolism
chemical_list: D013431:Sulfates; D013440:Sulfides; D007501:Iron; D002119:Calcium Carbonate; D008697:Methane