1QQU
CRYSTAL STRUCTURE OF PORCINE BETA TRYPSIN WITH BOUND ACETATE ION
Summary for 1QQU
| Entry DOI | 10.2210/pdb1qqu/pdb |
| Descriptor | BETA TRYPSIN, CALCIUM ION, ACETATE ION, ... (4 entities in total) |
| Functional Keywords | serine protease, hydrolase |
| Biological source | Sus scrofa (pig) |
| Cellular location | Secreted, extracellular space: P00761 |
| Total number of polymer chains | 1 |
| Total formula weight | 23590.65 |
| Authors | Johnson, A.,Gautham, N.,Pattabhi, V. (deposition date: 1999-06-09, release date: 2000-06-14, Last modification date: 2024-11-20) |
| Primary citation | Johnson, A.,Gautham, N.,Pattabhi, V. Crystal structure at 1.63 A resolution of the native form of porcine beta-trypsin: revealing an acetate ion binding site and functional water network. Biochim.Biophys.Acta, 1435:7-21, 1999 Cited by PubMed Abstract: The active center of a serine protease is the catalytic triad composed of His-57, Ser-195 and Asp-102. The existing crystal structure data on serine proteases have not fully answered a number of fundamental questions relating to the catalytic activity of serine proteases. The new high resolution native porcine beta-trypsin (BPT) structure is aimed at extending the knowledge on the conformation of the active site and the ordered water structure within and around the active site. The crystal structure of BPT has been determined at 1.63 A resolution. An acetate ion bound at the active site of a trypsin molecule by both classical hydrogen bonds and C-HellipsisO hydrogen bonds has been identified for the first time. A large network of water molecules extending from the recognition amino acid Asp-184 to the entry of the active site has been observed in the BPT structure. A detailed comparison with inhibitor complexes and autolysates indicates that the sulfate ion and the acetate ion bind at the same site of the trypsin molecule. The Ser-195 Cbeta-Ogamma-His-57 Nepsilon angle in the catalytic triad of BPT is intermediate between the corresponding values of the complex and native structure due to acetate ion binding. The network of waters from the recognition amino acid to the active site entry is probably the first ever complete picture of functional waters around the active site. Structural comparisons show that the functional waters involved in the binding of small molecule inhibitors and protease inhibitors are distinctly different. PubMed: 10561533DOI: 10.1016/S0167-4838(99)00202-2 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.63 Å) |
Structure validation
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