English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  A realistic in silico model for structure/function studies of molybdenum–copper CO dehydrogenase

Rokhsana, D., Large, T. A. G., Dienst, M. C., Retegan, M., & Neese, F. (2016). A realistic in silico model for structure/function studies of molybdenum–copper CO dehydrogenase. Journal of Biological Inorganic Chemistry, 21(4), 491-499. doi:10.1007/s00775-016-1359-6.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Rokhsana, Dalia1, Author
Large, Tao A. G.1, Author
Dienst, Morgan C.1, Author
Retegan, Marius2, Author           
Neese, Frank2, Author           
Affiliations:
1Department of Chemistry, Whitman College, Walla Walla, WA, 99362, USA, ou_persistent22              
2Research Department Neese, Max Planck Institute for Chemical Energy Conversion, Max Planck Society, ou_3023886              

Content

show
hide
Free keywords: CO dehydrogenase; Molybdenum-copper bimetallic site; Density functional theory; Quantum mechanics; Computational model
 Abstract: CO dehydrogenase (CODH) is an environmentally crucial bacterial enzyme that oxidizes CO to CO2 at a Mo–Cu active site. Despite the close to atomic resolution structure (1.1 Å), significant uncertainties have remained with regard to the protonation state of the water-derived equatorial ligand coordinated at the Mo-center, as well as the nature of intermediates formed during the catalytic cycle. To address the protonation state of the equatorial ligand, we have developed a realistic in silico QM model (~179 atoms) containing structurally essential residues surrounding the active site. Using our QM model, we examined each plausible combination of redox states (MoVI–CuI, MoV–CuII, MoV–CuI, and MoIV–CuI) and Mo-coordinated equatorial ligands (O2−, OH, H2O), as well as the effects of second-sphere residues surrounding the active site. Herein, we present a refined computational model for the Mo(VI) state in which Glu763 acts as an active site base, leading to a MoO2-like core and a protonated Glu763. Calculated structural and spectroscopic data (hyperfine couplings) are in support of a MoO2-like core in agreement with XRD data. The calculated two-electron reduction potential (E = −467 mV vs. SHE) is in reasonable agreement with the experimental value (E = −558 mV vs. SHE) for the redox couple comprising an equatorial oxo ligand and protonated Glu763 in the MoVI–CuI state and an equatorial water in the MoIV–CuI state. We also suggest a potential role of second-sphere residues (e.g., Glu763, Phe390) based on geometric changes observed upon exclusion of these residues in the most plausible oxidized states.

Details

show
hide
Language(s): eng - English
 Dates: 2015-11-122016-05-262016-07-01
 Publication Status: Published in print
 Pages: 9
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1007/s00775-016-1359-6
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Journal of Biological Inorganic Chemistry
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Berlin : Springer
Pages: - Volume / Issue: 21 (4) Sequence Number: - Start / End Page: 491 - 499 Identifier: ISSN: 0949-8257
CoNE: https://pure.mpg.de/cone/journals/resource/954925573943