This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1ayp
From Proteopedia
|
A PROBE MOLECULE COMPOSED OF SEVENTEEN PERCENT OF TOTAL DIFFRACTING MATTER GIVES CORRECT SOLUTIONS IN MOLECULAR REPLACEMENT
Contents |
Overview
It is often found in the crystallization of enzyme-inhibitor complexes, that an inhibitor causes crystal packing which is different to that of, native protein. This is the case for crystals of human non-pancreatic, secreted phospholipase A(2) (124 residues) containing six molecules in the, asymmetric unit when the protein is complexed with a potential acylamino, analogue of a phospholid. The hexameric structure was determined by, molecular replacement using the structure of monomeric native protein as a, probe. As an extension to the experiment, it was tested whether a backbone, polypeptide composed of 17% of a known monomeric structure could find its, correct position on a target molecule in molecular replacement. A probe, model composed of the backbone atoms of the N-terminal 77 residues of, lysine-, arginine-, ornithine-binding protein (LAO, a total of 238, residues) liganded with lysine correctly finds its position on LAO, liganded with histidine which crystallizes as a monomer in the asymmetric, unit. The results indicate that as little as 17% of total diffracting, matter can be used in molecular replacement to solve crystal structures or, to obtain phase information which can be combined with phases obtained by, the isomorphous-replacement method.
Disease
Known diseases associated with this structure: Colorectal cancer, sporadic OMIM:[172411]
About this Structure
1AYP is a Single protein structure of sequence from Homo sapiens with CA and INB as ligands. Active as Phospholipase A(2), with EC number 3.1.1.4 Full crystallographic information is available from OCA.
Reference
A probe molecule composed of seventeen percent of total diffracting matter gives correct solutions in molecular replacement., Oh BH, Acta Crystallogr D Biol Crystallogr. 1995 Mar 1;51(Pt 2):140-4. PMID:15299314
Page seeded by OCA on Mon Nov 12 16:03:51 2007
Categories: Homo sapiens | Phospholipase A(2) | Single protein | Oh, B.H. | CA | INB | Hydrolase
