Linear-dichroic Triplet-minus-Singlet Absorbance Difference Spectra of Borohydride-treated Reaction Centres of Rhodobacter sphaeroides R26

Linear-dichroic triplet-minus-singlet absorbance difference spectra of borohydride-treated reaction centres of Rhodobacter sphaeroides R26 have been measured by the technique of absorbance detected magnetic resonance (ADMR) in zero field in the wavelength region between 450 and 950 nm. They were compared with spectra of untreated reaction centres. Besides the absence of the absorbance of the removed B800M ‘accessory monomer’ pigment a blue shift of about 7 nm of the remaining band in the 800 nm region occurs.