Structure and topology of cytochrome f in pea chloroplast membranes

Abstract

A transmembrane arrangement of cytochrome f in chloroplast thylakoid membranes, with the N-terminal heme-containing region in the intrathylakoid space and a 15 amino acid C-terminal sequence in the stroma, is suggested by the amino acid sequence deduced from the nucleotide sequence of the pea chloroplast gene. This topology has been confirmed by partial proteolysis of the polypeptide in intact and disrupted thylakoid membranes and in inside-out and right-side-out vesicles of chloroplast membranes.