Multicellular, filamentous, sulfur-oxidizing bacteria, known as cable bacteria, were discovered attached to fibers of a carbon brush electrode serving as an anode of a benthic microbial fuel cell (BMFC). The BMFC had been operated in a temperate estuarine environment for over a year before collecting anode samples for scanning electron microscopy and phylogenetic analyses. Individual filaments were attached by single terminus cells with networks of pilus-like nano-filaments radiating out from these cells, across the anode fiber surface, and between adjacent attachment locations. Current harvesting by the BMFC poised the anode at potentials of ~170–250 mV vs. SHE, and these surface potentials appear to have allowed the cable bacteria to use the anode as an electron acceptor in a completely anaerobic environment. A combination of catalyzed reporter deposition fluorescent in situ hybridization (CARD-FISH) and 16S rRNA gene sequence analysis confirmed the phylogeny of the cable bacteria and showed that filaments often occurred in bundles and in close association with members of the genera Desulfuromonas. However, the Desulfobulbaceae Operational Taxonomic Units (OTUs) from the 16S sequencing did not cluster closely with other putative cable bacteria sequences suggesting that the taxonomic delineation of cable bacteria is far from complete.

This study represents the first characterization of sand microbiota in migrating barchan sand dunes. Bacterial communities were studied through direct counts and cultivation, as well as 16S rRNA gene and metagenomic sequence analysis to gain an understanding of microbial abundance, diversity, and potential metabolic capabilities. Direct on-grain cell counts gave an average of 5.3 ± 0.4 x 105 cells g-1 of sand. Cultured isolates (N = 64) selected for 16S rRNA gene sequencing belonged to the phyla Actinobacteria (58%), Firmicutes (27%) and Proteobacteria (15%). Deep-sequencing of 16S rRNA gene amplicons from 18 dunes demonstrated a high relative abundance of Proteobacteria, particularly enteric bacteria, and a dune-specific-pattern of bacterial community composition that correlated with dune size. Shotgun metagenome sequences of two representative dunes were analyzed and found to have similar relative bacterial abundance, though the relative abundances of eukaryotic, viral and enterobacterial sequences were greater in sand from the dune closer to a camel-pen. Functional analysis revealed patterns similar to those observed in desert soils; however, the increased relative abundance of genes encoding sporulation and dormancy are consistent with the dune microbiome being well-adapted to the exceptionally hyper-arid Qatari desert.

The deep marine subsurface is a heterogeneous environment in which the assembly of microbial communities is thought to be controlled by a combination of organic matter deposition, electron acceptor availability, and sedimentology. However, the relative importance of these factors in structuring microbial communities in marine sediments remains unclear. The South China Sea (SCS) experiences significant variability in sedimentation across the basin and features discrete changes in sedimentology as a result of episodic deposition of turbidites and volcanic ashes within lithogenic clays and siliceous or calcareous ooze deposits throughout the basin's history. Deep subsurface microbial communities were recently sampled by the International Ocean Discovery Program (IODP) at three locations in the SCS with sedimentation rates of 5, 12, and 20 cm per thousand years. Here, we used Illumina sequencing of the 16S ribosomal RNA gene to characterize deep subsurface microbial communities from distinct sediment types at these sites. Communities across all sites were dominated by several poorly characterized taxa implicated in organic matter degradation, including Atribacteria, Dehalococcoidia, and Aerophobetes. Sulfate-reducing bacteria comprised only 4% of the community across sulfate-bearing sediments from multiple cores and did not change in abundance in sediments from the methanogenic zone at the site with the lowest sedimentation rate. Microbial communities were significantly structured by sediment age and the availability of sulfate as an electron acceptor in pore waters. However, microbial communities demonstrated no partitioning based on the sediment type they inhabited. These results indicate that microbial communities in the SCS are structured by the availability of electron donors and acceptors rather than sedimentological characteristics.

Salze der Perfluororganosulfanmonosulfonsäuren werden durch Umsetzungen von RfSxCl mit K2S2O5 oder M2S2O3 dargestellt. Durch Reaktion des Kaliumsalzes mit einem stark sauren Kationenaustauscher kann die freie Säure CF3SSSO3H erhalten werden. Sie ist thermisch labil und ist mit einem pKs‐Wert von ca. –0,5 eine den Polyphosphorsäuren vergleichbar starke Säure. Metathesereaktionen der Kaliumsalze mit [(C6H5)4M] Cl (M = P, As) bzw. [R4N][ClO4] (R = n‐C3H7, n‐C4H9) ergeben gut kristallisierende Substanzen. Durch Einkristall‐Röntgenstrukturanalysen werden die Polysulfansulfon‐Einheiten nachgewiesen. S–S‐Bindungen werden auch durch Chlorolyserreaktionen bestätigt. Sowohl mit Cl2 als auch mit SCl2 entstehen RfSxCl bzw. RfSx+1Cl und ClSO2OM. Auf diese Weise läßt sich erstmals CF3SSSCl herstellen. Die Reaktionen von CF3SeBr und K2S2O5 führen zu K[CF3SeSO3], das sich zu CF3SeSeCF3, K2S2O6, SO2 und KBr zersetzt. Die Umsetzung von S2Cl2 mit (CH3)3SiNSO liefert als Hauptprodukt S2(NSO)2 und in geringen Mengen Sx(NSO)2 (x = 3, 4, 5). Während die Hydrolyse von S2(NSO)2 quantitativ (NH4)2S4O6 ergibt, erhält man mit dem Sx(NSO)2‐Gemisch, das nicht aufgetrennt werden kann, Ammoniumpolysulfandisulfonate. Es wird gezeigt, daß das chemische Verhalten von S2(NSO)2 durch die Disproportionierung zu S(NSO)2 und Schwefel bestimmt wird. Weitere Sulfinylimine werden durch Metathese von XNSO (X = Cl, Br) mit AgSCN bzw. AgSeCN synthetisiert. Während die Strukturen von S2(NSO)2 und OSNSCN röntgenstrukturanalytisch ermittelt werden, zeigen spektroskopische Unterschuchungen, daß OSNSeCN isostrukturell mit OSNSCN ist.

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