1ho0 | pdb_00001ho0
NEW B-CHAIN MUTANT OF BOVINE INSULIN
Structural highlights
Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe solution structure of a new B-chain mutant of bovine insulin, in which the cysteines B7 and B19 are replaced by two serines, has been determined by circular dichroism, 2D-NMR and molecular modeling. This structure is compared with that of the oxidized B-chain of bovine insulin [Hawkins et al. (1995) Int. J. Peptide Protein Res.46, 424-433]. Circular dichroism spectroscopy showed in particular that a higher percentage of helical secondary structure for the B-chain mutant is estimated in trifluoroethanol solution in comparison with the oxidized B-chain. 2D-NMR experiments confirmed, among multiple conformations, that the B-chain mutant presents defined secondary structures such as a alpha-helix between residues B9 and B19, and a beta-turn between amino acids B20 and B23 in aqueous trifluoroethanol. The 3D structures, which are consistent with NMR data and were obtained using a simulated annealing protocol, showed that the tertiary structure of the B-chain mutant is better resolved and is more in agreement with the insulin crystal structure than the oxidized B-chain structure described by Hawkins et al. An explanation could be the presence of two sulfonate groups in the oxidized insulin B-chain. Either by their charges and/or their size, such chemical groups could play a destructuring effect and thus could favor peptide flexibility and conformational averaging. Thus, this study provides new insights on the folding of isolated B-chains. A new B-chain mutant of insulin: comparison with the insulin crystal structure and role of sulfonate groups in the B-chain structure.,Dupradeau FY, Richard T, Le Flem G, Oulyadi H, Prigent Y, Monti JP J Pept Res. 2002 Jul;60(1):56-64. PMID:12081626[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferencesContents | ||||||||||||||||
