The frayed N-terminal of the inhibitor protein of bovine mitochondrial F1-ATPase

The N-terminal region of the bovine mitochondrial F1-ATPase inhibitor protein is frayed. In three independently isolated samples about 62% of chains start at glycine-1. A further 22% of chains start at residue 2, serine, and the remainder at residue 3, glutamic acid. No evidence can be found for alpha-N-formylglycine reported previously. The fraying may be a consequence of proteolytic processing of the precursor of the inhibitor protein during entry into the mitochondrion.