@article {ISI:000295971300003,
	title = {{Bacterial sulfur cycling shapes microbial communities in surface sediments of an ultramafic hydrothermal vent field}},
	journal = {ENVIRONMENTAL MICROBIOLOGY},
	volume = {13},
	number = {10},
	year = {2011},
	month = {oct},
	pages = {2633{\textendash}2648},
	type = {Article},
	abstract = {The ultramafic-hosted Logatchev hydrothermal field (LHF) is characterized by vent fluids, which are enriched in dissolved hydrogen and methane compared with fluids from basalt-hosted systems. Thick sediment layers in LHF are partly covered by characteristic white mats. In this study, these sediments were investigated in order to determine biogeochemical processes and key organisms relevant for primary production. Temperature profiling at two mat-covered sites showed a conductive heating of the sediments. Elemental sulfur was detected in the overlying mat and metal-sulfides in the upper sediment layer. Micro-profiles revealed an intensive hydrogen sulfide flux from deeper sediment layers. Fluorescence in situ hybridization showed that filamentous and vibrioid, Arcobacter-related Epsilonproteobacteria dominated the overlying mats. This is in contrast to sulfidic sediments in basalt-hosted fields where mats of similar appearance are composed of large sulfur-oxidizing Gammaproteobacteria. Epsilonproteobacteria (7-21{\%}) and Deltaproteobacteria (20-21{\%}) were highly abundant in the surface sediment layer. The physiology of the closest cultivated relatives, revealed by comparative 16S rRNA sequence analysis, was characterized by the capability to metabolize sulfur components. High sulfate reduction rates as well as sulfide depleted in (34)S further confirmed the importance of the biogeochemical sulfur cycle. In contrast, methane was found to be of minor relevance for microbial life in mat-covered surface sediments. Our data indicate that in conductively heated surface sediments microbial sulfur cycling is the driving force for bacterial biomass production although ultramafichosted systems are characterized by fluids with high levels of dissolved methane and hydrogen.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {1462-2912},
	doi = {10.1111/j.1462-2920.2011.02530.x},
	author = {Schauer, Regina and Roy, Hans and Augustin, Nico and Gennerich, Hans-Hermann and Peters, Marc and Wenzhoefer, Frank and Amann, Rudolf and Meyerdierks, Anke}
}
@article {ISI:000299052400011,
	title = {{Thermophilic anaerobic oxidation of methane by marine microbial consortia}},
	journal = {ISME JOURNAL},
	volume = {5},
	number = {12},
	year = {2011},
	month = {dec},
	pages = {1946{\textendash}1956},
	type = {Article},
	abstract = {The anaerobic oxidation of methane (AOM) with sulfate controls the emission of the greenhouse gas methane from the ocean floor. AOM is performed by microbial consortia of archaea (ANME) associated with partners related to sulfate-reducing bacteria. In vitro enrichments of AOM were so far only successful at temperatures {\textless}= 25 degrees C; however, energy gain for growth by AOM with sulfate is in principle also possible at higher temperatures. Sequences of 16S rRNA genes and core lipids characteristic for ANME as well as hints of in situ AOM activity were indeed reported for geothermally heated marine environments, yet no direct evidence for thermophilic growth of marine ANME consortia was obtained to date. To study possible thermophilic AOM, we investigated hydrothermally influenced sediment from the Guaymas Basin. In vitro incubations showed activity of sulfate-dependent methane oxidation between 5 and 70 degrees C with an apparent optimum between 45 and 60 degrees C. AOM was absent at temperatures {\textgreater}= 75 degrees C. Long-term enrichment of AOM was fastest at 50 degrees C, yielding a 13-fold increase of methane-dependent sulfate reduction within 250 days, equivalent to an apparent doubling time of 68 days. The enrichments were dominated by novel ANME-1 consortia, mostly associated with bacterial partners of the deltaproteobacterial HotSeep-1 cluster, a deeply branching phylogenetic group previously found in a butane-amended 60 degrees C-enrichment culture of Guaymas sediments. The closest relatives (Desulfurella spp.; Hippea maritima) are moderately thermophilic sulfur reducers. Results indicate that AOM and ANME archaea could be of biogeochemical relevance not only in cold to moderate but also in hot marine habitats. The ISME Journal (2011) 5, 1946-1956; doi: 10.1038/ismej.2011.77; published online 23 June 2011},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {1751-7362},
	doi = {10.1038/ismej.2011.77},
	author = {Holler, Thomas and Widdel, Friedrich and Knittel, Katrin and Amann, Rudolf and Kellermann, Matthias Y and Hinrichs, Kai-Uwe and Teske, Andreas and Boetius, Antje and Wegener, Gunter}
}
