1PEK

STRUCTURE OF THE COMPLEX OF PROTEINASE K WITH A SUBSTRATE-ANALOGUE HEXA-PEPTIDE INHIBITOR AT 2.2 ANGSTROMS RESOLUTION

Summary for 1PEK

• Entry DOI: 10.2210/pdb1pek/pdb
• Descriptor: PROTEINASE K, PEPTIDE PRO-ALA-PRO-PHE, D-DAL-ALA-NH2, ... (4 entities in total)
• Functional Keywords: hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Tritirachium album (Engyodontium album)
• Total number of polymer chains: 3
• Total formula weight: 29547.51

Authors

Betzel, C.,Singh, T.P.,Visanji, M.,Peters, K.,Fittkau, S.,Saenger, W.,Wilson, K.S. (deposition date: 1993-01-19, release date: 1994-01-31, Last modification date: 2024-10-30)

Primary citation

Betzel, C.,Singh, T.P.,Visanji, M.,Peters, K.,Fittkau, S.,Saenger, W.,Wilson, K.S.
Structure of the complex of proteinase K with a substrate analogue hexapeptide inhibitor at 2.2-A resolution.
J.Biol.Chem., 268:15854-15858, 1993

PubMed Abstract: The crystal structure of a transition state/product complex formed by the interaction between proteinase K and the substrate analogue N-Ac-L-Pro-L-Ala-L-Pro-L-Phe-D-Ala-L-Ala-NH2 has been determined at a resolution of 2.2 A and refined to an R-factor of 0.165 for 12,725 reflections. The inhibitor forms a stable complex through a series of hydrogen bonds with protein atoms and water molecules. The inhibitor is hydrolyzed between Phe 4I and D-Ala5I (I indicates inhibitor). The two fragments are separated by a distance of 3.07 A between the carbonyl carbon and the main chain nitrogen. Both fragments remain bound to the protein. The N-terminal fragment occupies subsites S5 to S1, whereas the C-terminal part is bound in S1' and S2', the first time that electron density for a substrate analogue has been observed in the P1' and P2' sites of a subtilisin-like enzyme. The flexible segments of the substrate recognition sites Gly100-Tyr104 and Ser132-Gly136 move appreciably to accommodate the inhibitor. Biochemical results indicate an inhibition by this specifically designed peptide of 95%.

PubMed: 8340410

Experimental method

X-RAY DIFFRACTION (2.2 Å)