@article {Teske2016,
	title = {{The Guaymas Basin Hiking Guide to Hydrothermal Mounds, Chimneys, and Microbial Mats: Complex Seafloor Expressions of Subsurface Hydrothermal Circulation}},
	journal = {Frontiers in Microbiology},
	volume = {7},
	year = {2016},
	pages = {75},
	abstract = {The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution. Mapping these hydrothermal features and sampling locations within the southern Guaymas Basin suggest linkages to underlying shallow sills and heat flow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for comprehensive surveys of the wider spreading region.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	doi = {10.3389/fmicb.2016.00075},
	author = {Teske, A P and de Beer, D and McKay, L J and Tivey, M K and Biddle, J F and Hoer, D R and Lloyd, K G and Lever, M A and Roy, H and Albert, D B and Mendlovitz, H P and MacGregor, B J}
}
@article {Salman-Carvalho2016,
	title = {{How Clonal Is Clonal? Genome Plasticity across Multicellular Segments of a "Candidatus Marithrix sp." Filament from Sulfidic, Briny Seafloor Sediments in the Gulf of Mexico}},
	journal = {Frontiers in Microbiology},
	volume = {7},
	year = {2016},
	pages = {1173},
	abstract = {"Candidatus Marithrix" is a recently described lineage within the group of large sulfur bacteria (Beggiatoaceae, Gammaproteobacteria). This genus of bacteria comprises vacuolated, attached-living filaments that inhabit the sediment surface around vent and seep sites in the marine environment. A single filament is ca. 100 mu m in diameter, several millimeters long, and consists of hundreds of clonal cells, which are considered highly polyploid. Based on these characteristics, "Candidatus Marithrix" was used as a model organism for the assessment of genomic plasticity along segments of a single filament using next generation sequencing to possibly identify hotspots of microevolution. Using six consecutive segments of a single filament sampled from a mud volcano in the Gulf of Mexico, we recovered ca. 90{\%} of the "Candidatus Marithrix" genome in each segment. There was a high level of genome conservation along the filament with average nucleotide identities between 99.98 and 100{\%}. Different approaches to assemble all reads into a complete consensus genome could not fill the gaps. Each of the six segment datasets encoded merely a few hundred unique nucleotides and 5 or less unique genes the residual content was redundant in all datasets. Besides the overall high genomic identity, we identified a similar number of single nucleotide polymorphisms (SNPs) between the clonal segments, which are comparable to numbers reported for other clonal organisms. An increase of SNPs with greater distance of filament segments was not observed. The polyploidy of the cells was apparent when analyzing the heterogeneity of reads within a segment. Here, a strong increase in single nucleotide variants, or "intrasegmental sequence heterogeneity" (ISH) events, was observed. These sites may represent hotspots for genome plasticity, and possibly microevolution, since two thirds of these variants were not co-localized across the genome copies of the multicellular filament.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	doi = {10.3389/fmicb.2016.01173},
	author = {Salman-Carvalho, V and Fadeev, E and Joye, S B and Teske, A P}
}
@article {Beaudoin2016,
	title = {{Impact of protists on a hydrocarbon-degrading bacterial community from deep-sea Gulf of Mexico sediments: A microcosm study}},
	journal = {Deep-Sea Research. Part II: Topical Studies in Oceanography},
	volume = {129},
	year = {2016},
	pages = {350{\textendash}359},
	abstract = {In spite of significant advancements towards understanding the dynamics of petroleum hydrocarbon degrading microbial consortia, the impacts (direct or indirect via grazing activities) of bacterivorous protists remain largely unknown. Microcosm experiments were used to examine whether protistan grazing affects the petroleum hydrocarbon degradation capacity of a deep-sea sediment microbial community from an active Gulf of Mexico cold seep. Differences in n-alkane content between native sediment microcosms and those treated with inhibitors of eukaryotes were assessed by comprehensive two-dimensional gas chromatography following 30{\textendash}90 day incubations and analysis of shifts in microbial community composition using small subunit ribosomal RNA gene clone libraries. More biodegradation was observed in microcosms supplemented with eukaryotic inhibitors. SSU rRNA gene clone libraries from oil-amended treatments revealed an increase in the number of proteobacterial clones (particularly $\gamma$-proteobacteria) after spiking sediments with diesel oil. Bacterial community composition shifted, and degradation rates increased, in treatments where protists were inhibited, suggesting protists affect the hydrocarbon degrading capacity of microbial communities in sediments collected at this Gulf of Mexico site.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0967-0645},
	doi = {10.1016/j.dsr2.2014.01.007},
	url = {http://www.sciencedirect.com/science/article/pii/S0967064514000216},
	author = {Beaudoin, D J and Carmichael, C A and Nelson, R K and Reddy, C M and Teske, A P and Edgcomb, V P}
}
@article {McKay2012,
	title = {{Spatial heterogeneity and underlying geochemistry of phylogenetically diverse orange and white Beggiatoa mats in Guaymas Basin hydrothermal sediments}},
	journal = {Deep-Sea Research. Part I: Oceanographic Research Papers},
	volume = {67},
	year = {2012},
	pages = {21{\textendash}31},
	abstract = {Sulfide-oxidizing bacteria of the genus Beggiatoa are found in conspicuous, colorful mats on the seafloor above active hydrothermal seeps at Guaymas Basin. Guaymas Beggiatoa filaments fall into discrete size classes representing at least five separate 16S rRNA phylotypes, and appear either white, yellow, or orange. During two R/V Atlantis cruises to Guaymas Basin, 78 temperature profiles were taken near and within 15 different orange and white Beggiatoa mats by the Alvin submersible to investigate spatial relationships between mat color and hydrothermal fluid seeps, as indicated by elevated temperatures. The surface temperatures from 78 profiles are similar to each other (on average 8{\textendash}12~{\textdegree}C, warmer than bare sediments at 3{\textendash}4~{\textdegree}C), indicating that Guaymas Basin Beggiatoa spp., although relying on the hydrothermal system for energy and carbon sources, live within a relatively cool temperature range. Temperatures from 40~cm below orange Beggiatoa versus white Beggiatoa are the same, at 84~{\textdegree}C averaged across all mat systems. However, within a single mat system, temperatures are higher beneath the predominantly orange center of the mat than beneath the white mat periphery. Push core transects across the orange-to-white color change of three Beggiatoa mats showed stronger upward compression of isotherms and metabolic zones beneath the orange mat center than beneath white mat periphery. Hydrothermal temperature gradients push the microbial processes generating carbon and energy sources for Beggiatoa mats towards the sediment surface. The resulting steep gradients of hydrothermal electron donors and carbon sources to the sediment surface, rather than the in situ temperature by itself, control the relative positioning of orange and white filaments within a Guaymas Basin Beggiatoa mat. Given the wide spectrum of temperature and hydrothermal flux regimes between different mats, the orange/white pattern represents a relative preference or even a competitive balance among different Beggiatoa types that establishes itself within each hydrothermal hot spot.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	doi = {10.1016/j.dsr.2012.04.011},
	url = {http://dx.doi.org/10.1016/j.dsr.2012.04.011},
	author = {McKay, L J and MacGregor, B J and Biddle, J F and Albert, D B and Mendlovitz, H P and Hoer, D R and Lipp, J S and Lloyd, K G and Teske, A P}
}
