@article {ISI:000338213900015,
	title = {{Deep-sea hydrothermal vent Epsilonproteobacteria encode a conserved and widespread nitrate reduction pathway (Nap)}},
	journal = {ISME JOURNAL},
	volume = {8},
	number = {7},
	year = {2014},
	month = {jul},
	pages = {1510{\textendash}1521},
	type = {Article},
	abstract = {Despite the frequent isolation of nitrate-respiring Epsilonproteobacteria from deep-sea hydrothermal vents, the genes coding for the nitrate reduction pathway in these organisms have not been investigated in depth. In this study we have shown that the gene cluster coding for the periplasmic nitrate reductase complex (nap) is highly conserved in chemolithoautotrophic, nitrate-reducing Epsilonproteobacteria from deep-sea hydrothermal vents. Furthermore, we have shown that the napA gene is expressed in pure cultures of vent Epsilonproteobacteria and it is highly conserved in microbial communities collected from deep-sea vents characterized by different temperature and redox regimes. The diversity of nitrate-reducing Epsilonproteobacteria was found to be higher in moderate temperature, diffuse flow vents than in high temperature black smokers or in low temperatures, substrate-associated communities. As NapA has a high affinity for nitrate compared with the membrane-bound enzyme, its occurrence in vent Epsilonproteobacteria may represent an adaptation of these organisms to the low nitrate concentrations typically found in vent fluids. Taken together, our findings indicate that nitrate reduction is widespread in vent Epsilonproteobacteria and provide insight on alternative energy metabolism in vent microorganisms. The occurrence of the nap cluster in vent, commensal and pathogenic Epsilonproteobacteria suggests that the ability of these bacteria to respire nitrate is important in habitats as different as the deep-sea vents and the human body.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {1751-7362},
	doi = {10.1038/ismej.2013.246},
	author = {Vetriani, Costantino and Voordeckers, James W and Crespo-Medina, Melitza and O{\textquoteright}Brien, Charles E and Giovannelli, Donato and Lutz, Richard A}
}
@article {ISI:000278233400031,
	title = {{Nautilia nitratireducens sp nov., a thermophilic, anaerobic, chemosynthetic, nitrate-ammonifying bacterium isolated from a deep-sea hydrothermal vent}},
	journal = {INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY},
	volume = {60},
	number = {5},
	year = {2010},
	month = {may},
	pages = {1182{\textendash}1186},
	type = {Article},
	abstract = {A thermophilic, anaerobic, chemosynthetic bacterium, designated strain MB-1(T), was isolated from the walls of an active deep-sea hydrothermal vent chimney on the East Pacific Rise at 9 degrees 50{\textquoteright} N 10 degrees 17{\textquoteright} W. The cells were Gram-negative-staining rods, approximately 1-1.5 mu m long and 0.3-0.5 mu m wide. Strain MB-1(T) grew at 25-65 degrees C (optimum 55 degrees C), with 10-35 g NaCl l(-1) (optimum 20 g l(-1)) and at pH 4.5-8.5 (optimum pH 7.0). Generation time under optimal conditions was 45.6 min. Growth occurred under chemolithoautotrophic conditions with H(2) as the energy source and CO(2) as the carbon source. Nitrate was used as the electron acceptor, with resulting production of ammonium. Thiosulfate, sulfur and selenate were also used as electron acceptors. No growth was observed in the presence of lactate, peptone or tryptone. Chemo-organotrophic growth occurred in the presence of acetate, formate, Casamino acids, sucrose, galactose and yeast extract under a N(2)/CO(2) gas phase. The G+C content of the genomic DNA was 36.0 mol{\%}. Phylogenetic analysis of the 16S rRNA gene sequence indicated that this organism is closely related to Nautilia profundicola AmH(T), Nautilia abyssi PH1209(T) and Nautilia lithotrophica 525(T) (95, 94 and 93{\%} sequence identity, respectively). On the basis of phylogenetic, physiological and genetic considerations, it is proposed that the organism represents a novel species within the genus Nautilia, Nautilia nitratireducens sp. nov. The type strain is MB-1(T) (=DSM 22087(T) =JCM 15746(T)).},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {1466-5026},
	doi = {10.1099/ijs.0.013904-0},
	author = {Perez-Rodriguez, Ileana and Ricci, Jessica and Voordeckers, James W and Starovoytov, Valentin and Vetriani, Costantino}
}
