Quantum Calculations Indicate Effective Electron Transfer between FMN and Benzoquinone in a New Crystal Structure of Escherichia coli WrbA.

TitleQuantum Calculations Indicate Effective Electron Transfer between FMN and Benzoquinone in a New Crystal Structure of Escherichia coli WrbA.
Publication TypeJournal Article
Year of Publication2016
AuthorsDegtjarik, O, Brynda, J, Ettrichova, O, Kuty, M, Sinha, D, Smatanova, IKuta, Carey, J, Ettrich, R, Řeha, D
JournalJ Phys Chem B
Volume120
Issue22
Pagination4867-77
Date Published2016 Jun 09
ISSN1520-5207
Abstract

UNLABELLED: Quantum mechanical calculations using the Marcus equation are applied to compare the electron-transfer probability for two distinct crystal structures of the Escherichia coli protein WrbA, an FMN-dependent

NAD(P)H: quinone oxidoreductase, with the bound substrate benzoquinone. The calculations indicate that the position of benzoquinone in a new structure reported here and solved at 1.33 Å resolution is more likely to be relevant for the physiological reaction of WrbA than a previously reported crystal structure in which benzoquinone is shifted by ∼5 Å. Because the true electron-acceptor substrate for WrbA is not yet known, the present results can serve to constrain computational docking attempts with potential substrates that may aid in identifying the natural substrate(s) and physiological role(s) of this enzyme. The approach used here highlights a role for quantum mechanical calculations in the interpretation of protein crystal structures.

DOI10.1021/acs.jpcb.5b11958
Alternate JournalJ Phys Chem B
PubMed ID27183467