INOR 28 |
| Methionine aminopeptidases (MetAPs) represent a unique class of protease that is responsible for the highly specific hydrolytic removal of N-terminal methionine residues from proteins and polypeptides. The role of the strictly conserved aspartate residue, D97, in the reaction mechanism of MetAP from Escherichia coli (EcMetAP-I) was investigated by examining the D97A, D97E and D97N altered enzymes. D97 is the lone carboxylate residue bound to the second divalent metal binding site in EcMetAP-I, based on X-ray crystallographically. Understanding the catalytic role of D97 may also add insight into the autosomal recessive disorder caused by D276 altered prolidase enzymes, since D276 is also the sole aspartate residue bound to the second metal binding site in prolidases, which contain an identical active site to MetAPs. We observe that alterations at position 97 affect function and influence the electronic structure of the bound metal ion(s), emphasizing the importance of this residue in catalysis. |
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Bioinorganic Chemistry: Enzymes and Coenzymes
8:30 AM-12:10 PM, Sunday, August 19, 2007 BCEC -- 208, Oral
Division of Inorganic Chemistry |