화학공학소재연구정보센터
Journal of Physical Chemistry A, Vol.114, No.21, 6308-6321, 2010
A Magnetic and Electronic Circular Dichroism Study of Azurin, Plastocyanin, Cucumber Basic Protein, and Nitrite Reductase Based on Time-Dependent Density Functional Theory Calculations
The excitation, circular dichroism, magnetic circular dichroism (MCD) and electron paramagnetic resonance (EPR) spectra of small models of four blue copper proteins are simulated on the TDDFT/BP86 level. X-Ray diffraction geometries are used for the modeling of the blue copper sites in azurin, plastocyanin, cucumber basic protein, and nitrite reductase. Comparison with experimental data reveals that the calculations reproduce most of the qualitative trends of the observed experimental spectra with some discrepancies in the orbital decompositions and the values or the excitation energies, the g(parallel to) components of the g tensor, and the components of the A tensor. These discrepancies are discussed relative to deficiencies in the time-dependent density functional theory (TDDFT) methodology, as opposed to previous studies which address them as a result of insufficient model size or poor performance of the BP86 functional. In addition, attempts are made to elucidate the correlation between the MCD and EPR signals.