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

Abstract

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 (N 2O). 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 turnoversmore » designed based on close mimics of the secondary coordination sphere of native NORs.« less

Authors:
 [1];  [1];  [2];  [2];  [1];  [1];  [3];  [3];  [3];  [1]
  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)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1247543
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Inorganic Chemistry; Journal Volume: 54; Journal Issue: 19
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Chakraborty, Saumen, Reed, Julian, Sage, Timothy, Branagan, Nicole C., Petrik, Igor D., Miner, Kyle D., Hu, Michael Y., Zhao, Jiyong, Alp, E. Ercan, and Lu, Yi. Recent advances in biosynthetic modeling of nitric oxide reductases and insights gained from nuclear resonance vibrational and other spectroscopic studies. United States: N. p., 2015. Web. doi:10.1021/acs.inorgchem.5b01105.
Chakraborty, Saumen, Reed, Julian, Sage, Timothy, Branagan, Nicole C., Petrik, Igor D., Miner, Kyle D., Hu, Michael Y., Zhao, Jiyong, Alp, E. Ercan, & Lu, Yi. Recent advances in biosynthetic modeling of nitric oxide reductases and insights gained from nuclear resonance vibrational and other spectroscopic studies. United States. doi:10.1021/acs.inorgchem.5b01105.
Chakraborty, Saumen, Reed, Julian, Sage, Timothy, Branagan, Nicole C., Petrik, Igor D., Miner, Kyle D., Hu, Michael Y., Zhao, Jiyong, Alp, E. Ercan, and Lu, Yi. 2015. "Recent advances in biosynthetic modeling of nitric oxide reductases and insights gained from nuclear resonance vibrational and other spectroscopic studies". United States. doi:10.1021/acs.inorgchem.5b01105.
@article{osti_1247543,
title = {Recent advances in biosynthetic modeling of nitric oxide reductases and insights gained from nuclear resonance vibrational and other spectroscopic studies},
author = {Chakraborty, Saumen and Reed, Julian and Sage, Timothy and Branagan, Nicole C. and Petrik, Igor D. and Miner, Kyle D. and Hu, Michael Y. and Zhao, Jiyong and Alp, E. Ercan and Lu, Yi},
abstractNote = {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.},
doi = {10.1021/acs.inorgchem.5b01105},
journal = {Inorganic Chemistry},
number = 19,
volume = 54,
place = {United States},
year = 2015,
month =
}
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