Quantum chemical calculation of type-1 cu reduction potential: ligand interaction and solvation effect

J Phys Chem A. 2009 Nov 19;113(46):12979-87. doi: 10.1021/jp905825q.

Abstract

Using active site model molecules consisting of approximately 100 atoms, the reduction potentials of five type-1 Cu centers in cucumber stellacyanin, fern dryopteris crassirhizoma plastocyanin, Met148Gln rusticyanin, wild type rusticyanin, and Met148Leu rusticyanin were calculated with a heterogeneous conductor-like polarizable continuum model and the B3LYP/6-311++G(2df,p) method. The results are 242, 366, 522, 667, and 825 mV, respectively, in good agreement with experimental values 260, 376, 563, 667, and 798 mV. Ligand interaction ( approximately 250 mV) and solvation effect ( approximately 250 mV) are found to be the main determinants of the relative E(0) of these five type-1 Cu centers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azurin / chemistry*
  • Computer Simulation
  • Copper / chemistry*
  • Ligands
  • Metalloproteins / chemistry*
  • Models, Chemical
  • Plant Proteins / chemistry*
  • Plastocyanin / chemistry*
  • Quantum Theory*

Substances

  • Ligands
  • Metalloproteins
  • Plant Proteins
  • rusticyanin
  • Azurin
  • stellacyanin protein, plant
  • Copper
  • Plastocyanin