English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Electronic Structural Flexibility of Heterobimetallic Mn/Fe Cofactors: R2lox and R2c Proteins

Shafaat, H. S., Griese, J. J., Pantazis, D. A., Roos, K., Andersson, C. S., Popović-Bijelić, A., et al. (2014). Electronic Structural Flexibility of Heterobimetallic Mn/Fe Cofactors: R2lox and R2c Proteins. Journal of the American Chemical Society, 136(38), 13399-13409. doi:10.1021/ja507435t.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Shafaat, Hannah S.1, Author              
Griese, Julia J.2, Author
Pantazis, Dimitrios A.3, Author              
Roos, Katarina4, Author
Andersson, Charlotta S.2, Author
Popović-Bijelić, Ana2, Author
Gräslund, Astrid2, Author
Siegbahn, Per E. M.4, Author
Neese, Frank3, Author              
Lubitz, Wolfgang1, Author              
Högbom, Martin2, Author
Cox, Nicholas1, Author              
Affiliations:
1Research Department Lubitz, Max Planck Institute for Chemical Energy Conversion, Max Planck Society, ou_3023873              
2Department of Biochemistry and Biophysics, Stockholm University, Stockholm SE-106 91, Sweden, ou_persistent22              
3Research Department Neese, Max Planck Institute for Chemical Energy Conversion, Max Planck Society, ou_3023886              
4Department of Physics, Stockholm University, Stockholm SE-106 91, Sweden, ou_persistent22              

Content

show
hide
Free keywords: -
 Abstract: The electronic structure of the Mn/Fe cofactor identified in a new class of oxidases (R2lox) described by Andersson and Högbom [Proc. Natl. Acad. Sci. U.S.A.2009, 106, 5633] is reported. The R2lox protein is homologous to the small subunit of class Ic ribonucleotide reductase (R2c) but has a completely different in vivo function. Using multifrequency EPR and related pulse techniques, it is shown that the cofactor of R2lox represents an antiferromagnetically coupled MnIII/FeIII dimer linked by a μ-hydroxo/bis-μ-carboxylato bridging network. The MnIII ion is coordinated by a single water ligand. The R2lox cofactor is photoactive, converting into a second form (R2loxPhoto) upon visible illumination at cryogenic temperatures (77 K) that completely decays upon warming. This second, unstable form of the cofactor more closely resembles the MnIII/FeIII cofactor seen in R2c. It is shown that the two forms of the R2lox cofactor differ primarily in terms of the local site geometry and electronic state of the MnIII ion, as best evidenced by a reorientation of its unique 55Mn hyperfine axis. Analysis of the metal hyperfine tensors in combination with density functional theory (DFT) calculations suggests that this change is triggered by deprotonation of the μ-hydroxo bridge. These results have important consequences for the mixed-metal R2c cofactor and the divergent chemistry R2lox and R2c perform.

Details

show
hide
Language(s): eng - English
 Dates: 2014-07-222014-09-152014-09-24
 Publication Status: Published in print
 Pages: 11
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1021/ja507435t
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Journal of the American Chemical Society
  Other : JACS
  Abbreviation : J. Am. Chem. Soc.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Washington, DC : American Chemical Society
Pages: - Volume / Issue: 136 (38) Sequence Number: - Start / End Page: 13399 - 13409 Identifier: ISSN: 0002-7863
CoNE: https://pure.mpg.de/cone/journals/resource/954925376870