Iron and sulfate reduction structure microbial communities in (sub-)Antarctic sediments

• Published in: The ISME Journal 2021-12, Vol.15 (12), p.3587-3604
• Main Authors: Wunder, Lea C., Aromokeye, David A., Yin, Xiuran, Richter-Heitmann, Tim, Willis-Poratti, Graciana, Schnakenberg, Annika, Otersen, Carolin, Dohrmann, Ingrid, Römer, Miriam, Bohrmann, Gerhard, Kasten, Sabine, Friedrich, Michael W.
• Format: Article
• Language: English
• Subjects: 38/22; 38/23; 38/71; 38/77; 38/90; 38/91; 631/158/855; 704/47; Abundance; Antarctic Regions; Biomedical and Life Sciences; Ecology; Environmental changes; Evolutionary Biology; Geologic Sediments; Glacial erosion; Glaciers; Iron; Life Sciences; Marine sediments; Microbial activity; Microbial Ecology; Microbial Genetics and Genomics; Microbiology; Microbiomes; Microbiota; Microorganisms; Oxidation-Reduction; Relative abundance; Reoxidation; RNA, Ribosomal, 16S - genetics; rRNA 16S; Sediments; Stable isotopes; Sulfate reduction; Sulfates; Sulfides; Sulfur
• ISSN: 1751-7362; 1751-7370
• DOI: 10.1038/s41396-021-01014-9

Permanently cold marine sediments are heavily influenced by increased input of iron as a result of accelerated glacial melt, weathering, and erosion. The impact of such environmental changes on microbial communities in coastal sediments is poorly understood. We investigated geochemical parameters that shape microbial community compositions in anoxic surface sediments of four geochemically differing sites (Annenkov Trough, Church Trough, Cumberland Bay, Drygalski Trough) around South Georgia, Southern Ocean. Sulfate reduction prevails in Church Trough and iron reduction at the other sites, correlating with differing local microbial communities. Within the order Desulfuromonadales , the family Sva1033, not previously recognized for being capable of dissimilatory iron reduction, was detected at rather high relative abundances (up to 5%) while other members of Desulfuromonadales were less abundant (