Recent advances in biosynthetic modeling of nitric oxide reductases and insights gained from nuclear resonance vibrational and other spectroscopic studies

Journal Article · Mon Oct 05 00:00:00 EDT 2015 · Inorganic Chemistry

DOI:https://doi.org/10.1021/acs.inorgchem.5b01105· OSTI ID:1247543

Chakraborty, Saumen ^[1]; Reed, Julian ^[1]; Sage, Timothy ^[2]; Branagan, Nicole C. ^[2]; Petrik, Igor D. ^[1]; Miner, Kyle D. ^[1]; Hu, Michael Y. ^[3]; Zhao, Jiyong ^[3]; Alp, E. Ercan ^[3]; Lu, Yi ^[1]

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1. Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
2. Northeastern Univ., Boston, MA (United States)
3. Argonne National Lab. (ANL), Argonne, IL (United States)

This Forum Article focuses on recent advances in structural and spectroscopic studies of biosynthetic models of nitric oxide reductases (NORs). NORs are complex metalloenzymes found in the denitrification pathway of Earth's nitrogen cycle where they catalyze the proton-dependent twoelectron reduction of nitric oxide (NO) to nitrous oxide (N₂O). While much progress has been made in biochemical and biophysical studies of native NORs and their variants, a. clear mechanistic understanding of this important metalloenzyme related to its function is still elusive. We report herein UV vis and nuclear resonance vibrational spectroscopy (NRVS) studies of mononitrosylated intermediates of the NOR reaction of a biosynthetic model. The ability to selectively substitute metals at either heme or nonheme metal sites allows the introduction of independent ⁵⁷Fe probe atoms at either site, as well as allowing the preparation of analogues of stable reaction intermediates by replacing either metal with a redox inactive metal. Together with previous structural and spectroscopic results, we summarize insights gained from studying these biosynthetic models toward understanding structural features responsible for the NOR activity and its mechanism. As a result, the outlook on NOR modeling is also discussed, with an emphasis on the design of models capable of catalytic turnovers designed based on close mimics of the secondary coordination sphere of native NORs.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1247543
• Journal Information: Inorganic Chemistry, Vol. 54, Issue 19; ISSN 0020-1669
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY