Stable binding interactions among subunits of the chloroplast ATP synthase (CF1‐CF0 as examined by solid support (nitrocellulose)‐subunit reconstitution‐immunoblotting

The technique termed solid support‐subunit reconstitution‐immunoblotting has been applied to examine stable binding interactions among renatured subunits of the chloroplast ATP synthase. Reconstitution of the CF1 subunits α, β and γ and subunit III of CF0 with thylakoid membrane polypeptides separated electrophoretically and transferred to nitrocellulose filters followed by immunodetection of hybrid subunit complexes revealed interactions between α‐ϵ, α‐CF0‐I, α‐CF0‐II, α‐δ, β‐γ, β‐CF0‐II β‐ϵ, β‐CF0‐III, γ‐CF0‐II, γ‐ϵ, γ‐CF0‐III, CF0‐III‐ϵ. Thus, the data confirm results on neighbour relationships of ATP synthase subunits obtained by cross‐linking and suggest that the method employed is generally applicable to examine protein‐protein binding interactions.