Methionine Aminopeptidase 1D (METAP1D) is a mitochondrion protein that belongs to the peptidase M24A family. METAP1D is overexpressed at the protein level in colon cancer cell lines and colon tumors as compared to normal tissues. N-terminal methionine removal is an important cellular process required for proper biological activity, subcellular localization, and eventual degradation of many proteins. METAP1D is also active with zinc, manganese or divalent ions. It may also play an important role in colon tumorigenesis.