TY  - JOUR
A1  - Vuillemin, Aurele
A1  - Horn, Fabian
A1  - Friese, Andre
A1  - Winkel, Matthias
A1  - Alawi, Mashal
A1  - Wagner, Dirk
A1  - Henny, Cynthia
A1  - Orsi, William D.
A1  - Crowe, Sean A.
A1  - Kallmeyer, Jens
T1  - Metabolic potential of microbial communities from ferruginous sediments
JF  - Environmental microbiology
N2  - Ferruginous (Fe-rich, SO4-poor) conditions are generally restricted to freshwater sediments on Earth today, but were likely widespread during the Archean and Proterozoic Eons. Lake Towuti, Indonesia, is a large ferruginous lake that likely hosts geochemical processes analogous to those that operated in the ferruginous Archean ocean. The metabolic potential of microbial communities and related biogeochemical cycling under such conditions remain largely unknown. We combined geochemical measurements (pore water chemistry, sulfate reduction rates) with metagenomics to link metabolic potential with geochemical processes in the upper 50 cm of sediment. Microbial diversity and quantities of genes for dissimilatory sulfate reduction (dsrAB) and methanogenesis (mcrA) decrease with increasing depth, as do rates of potential sulfate reduction. The presence of taxa affiliated with known iron- and sulfate-reducers implies potential use of ferric iron and sulfate as electron acceptors. Pore-water concentrations of acetate imply active production through fermentation. Fermentation likely provides substrates for respiration with iron and sulfate as electron donors and for methanogens that were detected throughout the core. The presence of ANME-1 16S and mcrA genes suggests potential for anaerobic methane oxidation. Overall our data suggest that microbial community metabolism in anoxic ferruginous sediments support coupled Fe, S and C biogeochemical cycling.
Y1  - 2018
U6  - https://doi.org/10.1111/1462-2920.14343
SN  - 1462-2912
SN  - 1462-2920
VL  - 20
IS  - 12
SP  - 4297
EP  - 4313
PB  - Wiley
CY  - Hoboken
ER  -