Major role of nitrite-oxidizing bacteria in dark ocean carbon fixation

作者：Maria Pachiadaki, Eva Sintes, Kristin Bergauer, Julia M. Brown, Nicholas R. Record, Brandon K. Swan, Mary Elizabeth Mathyer, Steven Hallam, Purificación López‐García, Yoshihiro Takaki, Takuro Nunoura, Tanja Woyke, Gerhard J. Herndl, Ramūnas Stepanauskas · 发表于：Science · 年份：2017 · DOI：10.1126/science.aan8260 · 被引用次数：332 · 研究领域：Microbial Community Ecology and Physiology、Marine and coastal ecosystems、Protist diversity and phylogeny

Carbon fixation by chemoautotrophic microorganisms in the dark ocean has a major impact on global carbon cycling and ecological relationships in the ocean's interior, but the relevant taxa and energy sources remain enigmatic. We show evidence that nitrite-oxidizing bacteria affiliated with the Nitrospinae phylum are important in dark ocean chemoautotrophy. Single-cell genomics and community metagenomics revealed that Nitrospinae are the most abundant and globally distributed nitrite-oxidizing bacteria in the ocean. Metaproteomics and metatranscriptomics analyses suggest that nitrite oxidation is the main pathway of energy production in Nitrospinae. Microautoradiography, linked with catalyzed reporter deposition fluorescence in situ hybridization, indicated that Nitrospinae fix 15 to 45% of inorganic carbon in the mesopelagic western North Atlantic. Nitrite oxidation may have a greater impact on the carbon cycle than previously assumed.