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Diversity and evolution of nitric oxide reduction

Murali, Ranjani and Pace, Laura A. and Sanford, Robert A. and Ward, Lewis M. and Lynes, Mackenzie and Hatzenpichler, Roland and Lingappa, Usha F. and Fischer, Woodward W. and Gennis, Robert B. and Hemp, James (2021) Diversity and evolution of nitric oxide reduction. . (Unpublished)

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Nitrogen is an essential element for life, with the availability of fixed nitrogen limiting productivity in many ecosystems. The return of oxidized nitrogen species to the atmospheric N₂ pool is predominately catalyzed by microbial denitrification (NO₃⁻ → NO₂⁻ → NO → N₂O → N₂). Incomplete denitrification can produce N2O as a terminal product, leading to an increase in atmospheric N₂O, a potent greenhouse and ozone depleting gas. The production of N₂O is catalyzed by nitric oxide reductase (NOR) members of the heme-copper oxidoreductase (HCO) superfamily. Here we propose that a number of uncharacterized HCO families perform nitric oxide reduction and demonstrate that an enzyme from Rhodothermus marinus, belonging to one of these families does perform nitric oxide reduction. These families have novel active-site structures and several have conserved proton channels, suggesting that they might be able to couple nitric oxide reduction to energy conservation. They also exhibit broad phylogenetic and environmental distributions, expanding the diversity of microbes that can perform denitrification. Phylogenetic analyses of the HCO superfamily demonstrate that nitric oxide reductases evolved multiple times independently from oxygen reductases, suggesting that complete denitrification evolved after aerobic respiration.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Murali, Ranjani0000-0003-4073-9910
Pace, Laura A.0000-0002-3311-8342
Sanford, Robert A.0000-0002-9607-9897
Ward, Lewis M.0000-0002-9290-2567
Lynes, Mackenzie0000-0002-9410-0285
Hatzenpichler, Roland0000-0002-5489-3444
Lingappa, Usha F.0000-0001-5691-6788
Fischer, Woodward W.0000-0002-8836-3054
Gennis, Robert B.0000-0002-3805-6945
Hemp, James0000-0001-7193-0553
Additional Information:The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license. Version 1 - October 15, 2021; Version 2 - November 10, 2021. We would like to thank NIH for funding this research (Grant # , Principle Investigator: Dr. Robert Gennis). We thank Sylvia Choi for providing pure ba3 oxygen reductase from Thermus thermophilus to use as a control for oxygen reductase assays and for heme extraction, Lici Schurig-Briccio for guidance in performing nitric oxide reductase assays with the Clark Electrode and Peter Yau at the University of Illinois’ Mass spectrometric facility for protein identification. We thank Alon Philosof and Connor Skennerton for valuable discussions on bioinformatics analysis. A portion of this research was performed under the Facilities Integrating Collaborations for User Science (FICUS) initiative (award 503546 to R.H.) and used resources at the DOE Joint Genome Institute and the Environmental Molecular Sciences Laboratory, which are DOE Office of Science User Facilities. Both facilities are sponsored by the Office of Biological and Environmental Research and operated under Contract Nos. DE-AC02-05CH11231 (JGI) and DE-AC05-76RL01830 (EMSL). The authors declare no competing interests.
Funding AgencyGrant Number
Department of Energy (DOE)DE-AC02-05CH11231
Department of Energy (DOE)DE-AC05-76RL01830
Record Number:CaltechAUTHORS:20211102-192525571
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Official Citation:Diversity and evolution of nitric oxide reduction. Ranjani Murali, Laura A Pace, Robert A Sanford, Lewis Ward, Mackenzie Lynes, Roland Hatzenpichler, Usha Lingappa, Woodward W. Fischer, Robert B Gennis, James Hemp. bioRxiv 2021.10.15.464467; doi:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111708
Deposited By: Tony Diaz
Deposited On:02 Nov 2021 21:21
Last Modified:11 Nov 2021 17:55

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