Diversity and evolution of nitric oxide reduction in bacteria and archaea

作者：Ranjani Murali, Laura Pace, Robert A. Sanford, Lewis M. Ward, Mackenzie M. Lynes, Roland Hatzenpichler, Usha Lingappa, Woodward W. Fischer, Robert B. Gennis, James Hemp · 发表于：Proceedings of the National Academy of Sciences · 年份：2024 · DOI：10.1073/pnas.2316422121 · 被引用次数：32 · 研究领域：Methane Hydrates and Related Phenomena、Marine and coastal ecosystems、Microbial Community Ecology and Physiology

Nitrous oxide is a potent greenhouse gas whose production is catalyzed by nitric oxide reductase (NOR) members of the heme-copper oxidoreductase (HCO) enzyme superfamily. We identified several previously uncharacterized HCO families, four of which (eNOR, sNOR, gNOR, and nNOR) appear to perform NO reduction. These families have novel active-site structures and several have conserved proton channels, suggesting that they might be able to couple NO reduction to energy conservation. We isolated and biochemically characterized a member of the eNOR family from the bacterium Rhodothermus marinus and found that it performs NO reduction. These recently identified NORs exhibited broad phylogenetic and environmental distributions, greatly expanding the diversity of microbes in nature capable of NO reduction. Phylogenetic analyses further demonstrated that NORs evolved multiple times independently from oxygen reductases, supporting the view that complete denitrification evolved after aerobic respiration.