光合释氧配合物及其蛋白质环境的理论研究

he photosynthesis is a very important energy transformation in nature. Because this reaction is in relation to solar energy transformation, water decomposition under room temperature and carbon dioxide fixation, there is great meaning on the research of this reaction mechanism. In the higher plant, water is oxidated on the cluster named oxygen-evolving complex (OEC for short), which is composed of manganese, oxygen and calcium. By Joliot-Kok cycle, electrons are transferred from OEC to water molecule, then the system releases oxygen. The OEC structure from XRD result is the starting point of this work. Energies under different multiple degrees are compared by quantum mechanism. Those manganese atoms are all on the high spin states. And then the charge distribution on every atoms in OEC are calculated when it is in protein environment(in the solution where dielectric constant is 4). Based on the crystal structure, the position of OEC is fixed, which regarded as several point charges, to get the position of these amino acid residues with α-C within 15 angstrom from the OEC by molecular dynamics simulation. At last, the interaction between OEC and every amino acid residues which connect with OEC directly are computed by using molecular mechanism. From those work, we hope to make some preparation for further research on this system by QM/MM or even QM method.