Proton gradient-induced changes of the interaction between CF0 and CF1 related to activation of the chloroplast ATP synthase

Thylakoid energization by light causes destabilization of CF0CF1 so that th e peripheral CF1 sector is more readily detached from the membrane by inter mediate concentrations of the chaotropic salt NaSCN. Here we have investiga ted the correlation between the proton gradient-induced change of CF0CF1 in teraction and CF0CF1 activation. The results indicate a close relationship between the two phenomena. The effect is most probably due to reduction of the electrostatic interaction between the two subcomplexes CF0 and CF1 as a consequence of protonations in the interface region. (C) 1999 Federation o f European Biochemical Societies.