Measurements of K+-driven Cl- uptake in thylakoids: inhibition of uptake by antibodies raised to the major polypeptides of the Cl(-)-efflux active particle(s).

The mechanism of a K+-driven Cl- accumulation against a concentration gradient was investigated by flow dialysis after addition of K+-Hepes. Non-specific chloride binding, measured in the presence of choline-Hepes, accounted for approximately 50% of the observed uptake in this system. The K+-Hepes-driven Cl- uptake was inhibited by poly-l-lysine and by two antibodies raised to the major polypeptides of the Cl(-)-efflux active particle. Poly-l-lysine had no effect on Cl- binding estimated with choline-Hepes.