Cleavage of the precursor of pea chloroplast cytochrome f by leader peptidase from Escherichia coli

Leader peptidase from Escherichia coli was able to process the precursor of pea cytochrome ƒ synthesised in vitro. N-Terminal sequencing established that cleavage by leader peptidase generated the same mature sequence as in pea chloroplasts. Processing by leader peptidase was much more efficient co-translationally rather than post-translationally, and the extent of post-translational processing declined with time suggesting that the cytochrome ƒ precursor folded to an uncleavable conformation. Detergent extracts of pea thylakoid membranes were unable to process the cytochrome ƒ precursor co- or post-translationally.