The present invention provides methionine aminopeptidases (MetAPs) with a
broad substrate range, particularly those capable of removing the
N-terminal Met from bulky or acidic penultimate residues. In preferred
embodiments, these MetAPs have mutations at the 233, 206 and/or 168
positions of SEQ ID NO:1. Preferably, amino acids at these residues are
substituted with glycine or threonine. Also provided are cells comprising
the MetAPs, DNA encoding the MetAPs, and methods of using the MetAPs.