{"id":14418,"date":"2020-01-15T13:52:34","date_gmt":"2020-01-15T21:52:34","guid":{"rendered":"https:\/\/www.darkenergybiosphere.org\/?post_type=publication&#038;p=14418"},"modified":"2020-02-03T14:46:19","modified_gmt":"2020-02-03T22:46:19","slug":"evidence-for-phylogenetically-and-catabolically-diverse-active-diazotrophs-in-deep-sea-sediment","status":"publish","type":"publication","link":"https:\/\/www.darkenergybiosphere.org\/publication\/evidence-for-phylogenetically-and-catabolically-diverse-active-diazotrophs-in-deep-sea-sediment\/","title":{"rendered":"Evidence for phylogenetically and catabolically diverse active diazotrophs in deep-sea sediment"},"content":{"rendered":"<p>Diazotrophic microorganisms regulate marine productivity by alleviating nitrogen limitation. However, we know little about the identity and activity of diazotrophs in deep-sea sediments, a habitat covering nearly two-thirds of the planet. Here, we identify candidate diazotrophs from Pacific Ocean sediments collected at 2893\u2009m water depth using\u00a0<sup>15<\/sup>N-DNA stable isotope probing and a novel pipeline for\u00a0<i>nifH<\/i> sequence analysis. Together, these approaches detect an unexpectedly diverse assemblage of active diazotrophs, including members of the <i>Acidobacteria<\/i>,\u00a0<i>Firmicutes<\/i>,\u00a0<i>Nitrospirae<\/i>,\u00a0<i>Gammaproteobacteria<\/i>, and\u00a0<i>Deltaproteobacteria. Deltaproteobacteria<\/i>, predominately members of the\u00a0 <i>Desulfobacterales<\/i>\u00a0and\u00a0<i>Desulfuromonadales<\/i>, are the most abundant diazotrophs detected, and display the most microdiversity of associated <i>nifH<\/i> sequences. Some of the detected lineages, including those within the <i>Acidobacteria<\/i>, have not previously been shown to fix nitrogen. The diazotrophs appear catabolically diverse, with the potential for using oxygen, nitrogen, iron, sulfur, and carbon as terminal electron acceptors. Therefore, benthic diazotrophy may persist throughout a range of geochemical conditions and provide a stable source of fixed nitrogen over geologic timescales. Our results suggest that nitrogen-fixing communities in deep-sea sediments are phylogenetically and catabolically diverse, and open a new line of inquiry into the ecology and biogeochemical impacts of deep-sea microorganisms.<\/p>\n","protected":false},"template":"","tags":[],"publication_type":[19],"_links":{"self":[{"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/publication\/14418"}],"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=14418"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/tags?post=14418"},{"taxonomy":"publication_type","embeddable":true,"href":"https:\/\/www.darkenergybiosphere.org\/wp-json\/wp\/v2\/publication_type?post=14418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}