A time-dependent density functional theory investigation of the spectroscopic properties of the beta-subunit in C-phycocyanin

作者：Ren, Yanliang; Wan, Jian^*; Xu, Xin; Zhang, Qingye; Yang, Guangfu

来源：Journal of Physical Chemistry B, 2006, 110(37): 18665-18669.

DOI：10.1021/jp064734v

• CYANOBACTERIUM MASTIGOCLADUS-LAMINOSUS
• CIRCULAR-DICHROISM SPECTRA
• EXCITATION-ENERGY TRANSFER
• RESOLVED RATE CONSTANTS
• UV-VISIBLE ABSORPTION
• CHROMOPHORE-PROTEIN
• DIMETHYL ESTER
• PHYCOBILISOMES
• MOLECULES
• EXCHANGE

By using time-dependent density functional theory combined with the polarizable continuum model, a satisfactory assignment of the absorption and circular dichroism spectra and energy transfer flow of the beta-subunit in C-phycocyanin (C-PC) was achieved when the protonation of beta-84 and beta-155 phycocyanobilin (PCB) and their interaction with the protein moiety in C-PC have been taken into account. We attribute the main peak for both beta-84 and beta-155 as arising from the pi electron excitation of the pyrrole rings and the shoulder peak as arising from the charge transfer from the asparate residue to PCBH+. The satisfactory agreement between theory and experiment suggests that Forster resonance theory prevails such that energy transfer occurs from beta(s)(beta-155) to beta(f)(beta-84).

• 出版日期2006-9-21
• 单位华中师范大学; 厦门大学