Persistent Spectral Hole Burning In The Antenna Protein CP47 Of Synechocystis SP. Mutant H114Q

Abstract

Spectral hole-burning is powerful tool for the study of fast relaxation processes (e.g. excited energy transfer - EET, electron transport - e.t.) in photosynthetic systems. Fast e.t. was systematically studied by transient hole-burning (THB) in absorption spectra of reaction centra in purple bacteria and green plants [1]. The THB in fluorescence of PSII particles was described in [2]. Persistent spectral hole-burning (PSHB) enabled to determine the hole-burning mechanism, the EET rate constants, electron-phonon coupling and frequency of protein phonons. The PSHB in fluorescence has been measured in antenna complexes: CP43 and CP47 of PSII [3], B800-850 of purple photosynthetic bacteria [4] and in chlorosomes of green sulphur photosynthetic bacteria [5]. Laser induced hole filling in fluorescence spectra of CP43 of PSII was presented recently in [6]. These data were obtained using wild type organisms. Here, we report an investigation of EET by fluorescence PSHB in photosynthetic antenna using H114Q mutation in the CP47 complex of Synechocystis sp. PCC 6803.