Über die Hemmung photosynthetischer Reaktionen isolierter Chloroplasten durch Chloroplasten-Antikörper

Abstract

The influence of two separated globuline fractions from rabbit antisera against isolated chloroplasts from Antirrhinum majus upon photosynthetic reactions of isolated chloroplasts from spinach has been investigated. The chloroplast antibodies had no effect on electron transport in a Hill reaction with ferricyanide, but one fraction inhibited noncyclic and cyclic ATP formation. This inhibition was reversed by preincubation of the antibody with coupling factor. Both globuline fractions inhibited photosynthetic NADP reduction; the inhibition of only one fraction was reversed by preincubation with ferredoxin-NADP-reductase. We conclude from these results that three components of photosynthetic activities are located on the surface of the thylakoids: the ATP forming system, the NADP-reductase, and an unknown factor participating in photosynthetic NADP reduction but not in ferricyanide reduction or cyclic electron transport