INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
Electric field effects on the reactivity of heme model systems
P.M. DE BIASE; F. DOCTOROVICH; D.H. MURGIDA; D.A. ESTRIN
CHEMICAL PHYSICS LETTERS
Año: 2007 vol. 434 p. 121 - 121
The active sites of proteins associated with lipid bilayer membranes are subject to moderately strong electric fields. However, the role of the electric field on the tuning of active site reactivity is still an open issue in most cases. In this paper we report DFT calculations of the effects of electric fields on the O2, CO, CN-, and NO ligand binding and on the redox potentials of heme model systems representing the active sites of typical hemeproteins, such as cytochrome c, and cytochrome P450. As expected, the observed electric field effects are consistent with the electric moments and susceptibilities of the investigated heme models. Electric fields of the order of 0.1 VÅ-1 affect significantly (up to 4 kcal/mol) the ligand dissociation energies, and the reduction potentials. In addition to the relevance of these results in understanding protein reactivity, electric field effects may also be useful for the design of novel electrochemical heme catalysts.