Electric Field Modulation of Electron Transfer in Bacterial Photosynthetic Reaction Centers

Multilayer Langmuir-Blodgett (LB) films of reaction centers from the photosynthetic bacterium Rhodopseudomonas sphaeroides have been fabricated with partial net orientation. From measurements of the light induced electron transfer reactions in reaction center films, we have succeeded in quantitating the electric field dependence of (1) the quantum yield of charge separation and (2) the kinetics of charge recombination.