@article {ISI:000368893500001,
	title = {{Microbial Communities in Methane- and Short Chain Alkane-Rich Hydrothermal Sediments of Guaymas Basin}},
	journal = {FRONTIERS IN MICROBIOLOGY},
	volume = {7},
	year = {2016},
	month = {jan},
	type = {Article},
	abstract = {The hydrothermal sediments of Guaymas Basin, an active spreading center in the Gulf of California (Mexico), are rich in porewater methane, short-chain alkanes, sulfate and sulfide, and provide a model system to explore habitat preferences of microorganisms, including sulfate-dependent, methane- and short chain alkane-oxidizing microbial communities. In this study, hot sediments (above 60 degrees C) covered with sulfur-oxidizing microbial mats surrounding a hydrothermal mound (termed {\textquoteleft}{\textquoteleft}Mat Mound{\{}{\textquoteright}{\textquoteright}{\}}) were characterized by porewater geochemistry of methane, C-2-C-6 short-chain alkanes, sulfate, sulfide, sulfate reduction rate measurements, in situ temperature gradients, bacterial and archaeal 16S rRNA gene clone libraries and V6 tag pyrosequencing. The most abundantly detected groups in the Mat mound sediments include anaerobic methane-oxidizing archaea of the ANME-1 lineage and its sister Glade ANME-1Guaymas, the uncultured bacterial groups SEEP-SRB2 within the Deltaproteobacteria and the separately branching HotSeep-1 Group; these uncultured bacteria are candidates for sulfate-reducing alkane oxidation and for sulfate-reducing syntrophy with ANME archaea. The archaeal dataset indicates distinct habitat preferences for ANME-1, ANME-1-Guaymas, and ANME-2 archaea in Guaymas Basin hydrothermal sediments. The bacterial groups SEEP-SRB2 and HotSeep-1 co-occur with ANME-1 and ANME-1Guaymas in hydrothermally active sediments underneath microbial mats in Guaymas Basin. We propose the working hypothesis that this mixed bacterial and archaeal community catalyzes the oxidation of both methane and short-chain alkanes, and constitutes a microbial community signature that is characteristic for hydrothermal and/or cold seep sediments containing both substrates.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {1664-302X},
	doi = {10.3389/fmicb.2016.00017},
	author = {Dowell, Frederick and Cardman, Zena and Dasarathy, Srishti and Kellermann, Matthias Y and Lipp, Julius S and Ruff, S Emil and Biddle, Jennifer F and McKay, Luke J and MacGregor, Barbara J and Lloyd, Karen G and Albert, Daniel B and Mendlovitz, Howard and Hinrichs, Kai-Uwe and Teske, Andreas}
}
@article {ISI:000326614000008,
	title = {{Sulfide oxidation, nitrate respiration, carbon acquisition, and electron transport pathways suggested by the draft genome of a single orange Guaymas Basin Beggiatoa (Cand. Maribeggiatoa) sp filament}},
	journal = {MARINE GENOMICS},
	volume = {11},
	year = {2013},
	month = {sep},
	pages = {53{\textendash}65},
	type = {Article},
	abstract = {A near-complete draft genome has been obtained for a single vacuolated orange Beggiatoa (Cand. Maribeggiatoa) filament from a Guaymas Basin seafloor microbial mat, the third relatively complete sequence for the Beggiatoaceae. Possible pathways for sulfide oxidation; nitrate respiration; inorganic carbon fixation by both Type II RuBisCO and the reductive tricarboxylic add cycle; acetate and possibly formate uptake; and energy-generating electron transport via both oxidative phosphorylation and the Rnf complex are discussed here. A role in nitrite reduction is suggested for an abundant orange cytochrome produced by the Guaymas strain; this has a possible homolog in Beggiatoa (Cand. Isobeggiatoa) sp. PS, isolated from marine harbor sediment, but not Beggiatoa alba B18LD, isolated from a freshwater rice field ditch. Inferred phylogenies for the Calvin-Benson-Bassham (CBB) cycle and the reductive (rTCA) and oxidative (TCA) tricarboxylic acid cycles suggest that genes encoding succinate dehydrogenase and enzymes for carboxylation and/or decarboxylation steps (including RuBisCO) may have been introduced to (or exported from) one or more of the three genomes by horizontal transfer, sometimes by different routes. Sequences from the two marine strains are generally more similar to each other than to sequences from the freshwater strain, except in the case of RuBisCO: only the Guaymas strain encodes a Type H enzyme, which (where studied) discriminates less against oxygen than do Type I RuBisCOs. Genes subject to horizontal transfer may represent key steps for adaptation to factors such as oxygen and carbon dioxide concentration, organic carbon availability, and environmental variability. (C) 2013 Elsevier B.V. All rights reserved.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {1874-7787},
	doi = {10.1016/j.margen2013.08.001},
	author = {MacGregor, Barbara J and Biddle, Jennifer F and Harbort, Christopher and Matthysse, Ann G and Teske, Andreas}
}
@article {ISI:000314891500014,
	title = {{Why Orange Guaymas Basin Beggiatoa spp. Are Orange: Single-Filament-Genome-Enabled Identification of an Abundant Octaheme Cytochrome with Hydroxylamine Oxidase, Hydrazine Oxidase, and Nitrite Reductase Activities}},
	journal = {APPLIED AND ENVIRONMENTAL MICROBIOLOGY},
	volume = {79},
	number = {4},
	year = {2013},
	month = {feb},
	pages = {1183{\textendash}1190},
	type = {Article},
	abstract = {Orange, white, and yellow vacuolated Beggiatoaceae filaments are visually dominant members of microbial mats found near sea floor hydrothermal vents and cold seeps, with orange filaments typically concentrated toward the mat centers. No marine vacuolate Beggiatoaceae are yet in pure culture, but evidence to date suggests they are nitrate-reducing, sulfide-oxidizing bacteria. The nearly complete genome sequence of a single orange Beggiatoa ({\{}{\textquoteright}{\textquoteright}{\}}Candidatus Maribeggiatoa{\{}{\textquoteright}{\textquoteright}{\}}) filament from a microbial mat sample collected in 2008 at a hydrothermal site in Guaymas Basin (Gulf of California, Mexico) was recently obtained. From this sequence, the gene encoding an abundant soluble orange-pigmented protein in Guaymas Basin mat samples (collected in 2009) was identified by microcapillary reverse-phase high-performance liquid chromatography (HPLC) nano-electrospray tandem mass spectrometry (mu LC-MS-MS) of a pigmented band excised from a denaturing polyacrylamide gel. The predicted protein sequence is related to a large group of octaheme cytochromes whose few characterized representatives are hydroxylamine or hydrazine oxidases. The protein was partially purified and shown by in vitro assays to have hydroxylamine oxidase, hydrazine oxidase, and nitrite reductase activities. From what is known of Beggiatoaceae physiology, nitrite reduction is the most likely in vivo role of the octaheme protein, but future experiments are required to confirm this tentative conclusion. Thus, while present-day genomic and proteomic techniques have allowed precise identification of an abundant mat protein, and its potential activities could be assayed, proof of its physiological role remains elusive in the absence of a pure culture that can be genetically manipulated.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0099-2240},
	doi = {10.1128/AEM.02538-12},
	author = {MacGregor, Barbara J and Biddle, Jennifer F and Siebert, Jason R and Staunton, Eric and Hegg, Eric L and Matthysse, Ann G and Teske, Andreas}
}
@article {ISI:000302950700011,
	title = {{Anaerobic oxidation of methane at different temperature regimes in Guaymas Basin hydrothermal sediments}},
	journal = {ISME JOURNAL},
	volume = {6},
	number = {5},
	year = {2012},
	month = {may},
	pages = {1018{\textendash}1031},
	type = {Article},
	abstract = {Anaerobic oxidation of methane (AOM) was investigated in hydrothermal sediments of Guaymas Basin based on delta C-13 signatures of CH4, dissolved inorganic carbon and porewater concentration profiles of CH4 and sulfate. Cool, warm and hot in-situ temperature regimes (15-20 degrees C, 30-35 degrees C and 70-95 degrees C) were selected from hydrothermal locations in Guaymas Basin to compare AOM geochemistry and 16S ribosomal RNA (rRNA), mcrA and dsrAB genes of the microbial communities. 16S rRNA gene clone libraries from the cool and hot AOM cores yielded similar archaeal types such as Miscellaneous Crenarchaeotal Group, Thermoproteales and anaerobic methane-oxidizing archaea (ANME)-1; some of the ANME-1 archaea formed a separate 16S rRNA lineage that at present seems to be limited to Guaymas Basin. Congruent results were obtained by mcrA gene analysis. The warm AOM core, chemically distinct by lower porewater sulfide concentrations, hosted a different archaeal community dominated by the two deep subsurface archaeal lineages Marine Benthic Group D and Marine Benthic Group B, and by members of the Methanosarcinales including ANME-2 archaea. This distinct composition of the methane-cycling archaeal community in the warm AOM core was confirmed by mcrA gene analysis. Functional genes of sulfate-reducing bacteria and archaea, dsrAB, showed more overlap between all cores, regardless of the core temperature. 16S rRNA gene clone libraries with Euryarchaeota-specific primers detected members of the Archaeoglobus clade in the cool and hot cores. A V6-tag high-throughput sequencing survey generally supported the clone library results while providing high-resolution detail on archaeal and bacterial community structure. These results indicate that AOM and the responsible archaeal communities persist over a wide temperature range. The ISME Journal (2012) 6, 1018-1031; doi:10.1038/ismej.2011.164; published online 17 November 2011},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {1751-7362},
	doi = {10.1038/ismej.2011.164},
	author = {Biddle, Jennifer F and Cardman, Zena and Mendlovitz, Howard and Albert, Daniel B and Lloyd, Karen G and Boetius, Antje and Teske, Andreas}
}
