1N51

Aminopeptidase P in complex with the inhibitor apstatin

Summary for 1N51

• Entry DOI: 10.2210/pdb1n51/pdb
• Related: 1A16 1AZ9 1JAW 1M35
• Related PRD ID: PRD_000553
• Descriptor: Xaa-Pro aminopeptidase, apstatin, MANGANESE (II) ION, ... (4 entities in total)
• Functional Keywords: aminopeptidase, proline specific, manganese enzyme, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Escherichia coli; More
• Cellular location: Cytoplasm: P15034
• Total number of polymer chains: 2
• Total formula weight: 50367.41

Authors

Graham, S.C.,Maher, M.J.,Lee, M.H.,Simmons, W.H.,Freeman, H.C.,Guss, J.M. (deposition date: 2002-11-03, release date: 2003-12-16, Last modification date: 2023-11-15)

Primary citation

Graham, S.C.,Maher, M.J.,Simmons, W.H.,Freeman, H.C.,Guss, J.M.
Structure of Escherichia coli aminopeptidase P in complex with the inhibitor apstatin.
Acta Crystallogr.,Sect.D, 60:1770-1779, 2004

PubMed Abstract: Aminopeptidase P (APPro) is a metalloprotease whose active site includes a dinuclear manganese(II) cluster. The enzyme cleaves the N-terminal residue from a polypeptide when the second residue is proline. A complex of Escherichia coli APPro (EcAPPro) with an inhibitor, apstatin [N-(2S,3R)-3-amino-2-hydroxy-4-phenyl-butanoyl-L-prolyl-L-prolyl-L-alaninamide], has been crystallized. Apstatin binds to the active site of EcAPPro with its N-terminal amino group coordinated to one of the two Mn(II) atoms at the metal centre. The apstatin hydroxyl group replaces a hydroxide ion which bridges the two metal atoms in the native enzyme. The first proline residue of apstatin lies in a small hydrophobic cleft. The structure of the apstatin-EcAPPro complex has been refined at 2.3 A resolution with residuals R = 0.179 and R(free) = 0.204. The structure of the complex illustrates how apstatin inhibits APPro and suggests how substrates may bind to the enzyme, but the basis of the proline-specificity remains elusive.

PubMed: 15388923
DOI: 10.1107/S0907444904018724

Experimental method

X-RAY DIFFRACTION (2.3 Å)