ACTION SPECTRA FOR THE ABSORBANCE CHANGE AT 880 nm AND FOR P870 FLUORESCENCE FROM A PHOTOSYNTHETIC REACTION CENTER*

Abstract— Photosynthetic reaction centers isolated from blue-green mutant strain R-26 of Rhodopseudomonas spheroides were used to study the action spectra for the light-induced absorption changes at 880 nm, and for the P870 fluorescence. These spectra indicated that a pigment, possibly bacteriopheophytin, with an absorption maximum at 757 nm is an intrinsic component of the reaction center and transfers energy to P870 with relatively high efficiency.