{"id":17382,"date":"2023-04-13T08:21:29","date_gmt":"2023-04-13T15:21:29","guid":{"rendered":"https:\/\/www.darkenergybiosphere.org\/?post_type=publication&#038;p=17382"},"modified":"2023-04-13T08:22:48","modified_gmt":"2023-04-13T15:22:48","slug":"physiological-and-metabolic-responses-of-chemolithoautotrophic-no3%e2%88%92-reducers-to-high-hydrostatic-pressure","status":"publish","type":"publication","link":"https:\/\/www.darkenergybiosphere.org\/publication\/physiological-and-metabolic-responses-of-chemolithoautotrophic-no3%e2%88%92-reducers-to-high-hydrostatic-pressure\/","title":{"rendered":"Physiological and metabolic responses of chemolithoautotrophic NO3\u2212 reducers to high hydrostatic pressure"},"content":{"rendered":"<p>We investigated the impact of pressure on thermophilic, chemolithoautotrophic NO3\u2212 reducing bacteria of the phyla <i>Campylobacterota<\/i>\u00a0and\u00a0<i>Aquificota<\/i> isolated from deep-sea hydrothermal vents. Batch incubations at 5 and 20\u2009MPa resulted in decreased NO3\u2212 consumption, lower cell concentrations, and overall slower growth in\u00a0<i>Caminibacter mediatlanticus<\/i>\u00a0(<i>Campylobacterota<\/i>) and <i>Thermovibrio ammonificans<\/i>\u00a0(<i>Aquificota<\/i>), relative to batch incubations near standard pressure (0.2\u00a0MPa) conditions. Nitrogen isotope fractionation effects from chemolithoautotrophic\u00a0NO3\u2212\u00a0reduction by both microorganisms were, on the contrary, maintained under all pressure conditions. Comparable chemolithoautotrophic\u00a0NO3\u2212\u00a0reducing activities between previously reported natural hydrothermal vent fluid microbial communities dominated by\u00a0<i>Campylobacterota<\/i>\u00a0at 25\u2009MPa and\u00a0<i>Campylobacterota<\/i>\u00a0laboratory isolates at 0.2\u00a0MPa, suggest robust similarities in cell-specific\u00a0NO3\u2212\u00a0reduction rates and doubling times between microbial populations and communities growing maximally under similar temperature conditions. Physiological and metabolic comparisons of our results with other studies of pressure effects on anaerobic chemolithoautotrophic processes (i.e., microbial S<sup>0<\/sup>-oxidation coupled to Fe(III) reduction and hydrogenotrophic methanogenesis) suggest that anaerobic chemolithoautotrophs relying on oxidation\u2013reduction (redox) reactions that yield higher Gibbs energies experience larger shifts in cell-specific respiration rates and doubling times at increased pressures. Overall, our results advance understanding of the role of pressure, its relationship with temperature and redox conditions, and their effects on seafloor chemolithoautotrophic\u00a0NO3\u2212\u00a0reduction and other anaerobic chemolithoautotrophic processes.<\/p>\n","protected":false},"template":"","tags":[],"publication_type":[19],"_links":{"self":[{"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/publication\/17382"}],"collection":[{"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/publication"}],"about":[{"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/types\/publication"}],"wp:attachment":[{"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/media?parent=17382"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/tags?post=17382"},{"taxonomy":"publication_type","embeddable":true,"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/publication_type?post=17382"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}