ELECTRIC LINEAR DICHROISM OF P700 CHLOROPHYLL U‐PROTEIN COMPLEXES

Abstract— The P700 chlorophyll a-protein complex (CPI) isolated from green plants was oriented in aqueous solutions using pulsed electric fields of up to 6700 V cm-1. The electric linear dichroism spectrum is reported in the range of 400–720nm. Positive peaks in the linear dichroism ΔA=AI- A1 (where AI and A1 are the absorbance components in which the polarizer orientation is parallel and perpendicular with respect to the electric field. respectively) are observed at 443 and 686 nm. The ΔA signal at 686 nm is discussed in terms of either a specialized chlorophyll form absorbing at 686 nm. or due to an exciton component absorbing at the same wavelength.