Summary for 4APE
Entry DOI | 10.2210/pdb4ape/pdb |
Descriptor | ENDOTHIAPEPSIN (2 entities in total) |
Functional Keywords | hydrolase (acid proteinase) |
Biological source | Cryphonectria parasitica |
Total number of polymer chains | 1 |
Total formula weight | 33813.86 |
Authors | Pearl, L.H.,Sewell, B.T.,Jenkins, J.A.,Cooper, J.B.,Blundell, T.L. (deposition date: 1986-06-09, release date: 1986-07-14, Last modification date: 2024-10-09) |
Primary citation | Pearl, L.,Blundell, T. The Active Site of Aspartic Proteinases FEBS Lett., 174:96-101, 1984 Cited by PubMed Abstract: The active site of the aspartic proteinase, endothiapepsin, has been defined by X-ray analysis and restrained least-squares refinement at 2.1 A resolution with a crystallographic agreement value of 0.16. The environments of the two catalytically important aspartyl groups are remarkably similar and the contributions of the NH2- and COOH-terminal domains to the catalytic centre are related by a local 2-fold axis. The carboxylates of the aspartyls share a hydrogen bond and have equivalent contacts to a bound water molecule or hydroxonium ion lying on the local diad. The main chains around 32 and 215 are connected by a novel interaction involving diad-related threonines. It is suggested that the two pKa values of the active site aspartyls arise from a structure not unlike that in maleic acid with a hydrogen-bonded intermediate species and a dicarboxylate characterised by electrostatic repulsions between the two negatively charged groups. PubMed: 6381096DOI: 10.1016/0014-5793(84)81085-6 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (2.1 Å) |
Structure validation
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