1HG7
High resolution structure of HPLC-12 type III antifreeze protein from Ocean Pout Macrozoarces americanus
Summary for 1HG7
| Entry DOI | 10.2210/pdb1hg7/pdb |
| Related | 1AME 1B7I 1B7J 1B7K 1EKL 1GZI 1JAB 1KDE 1KDF 1MSI 1MSJ 2AME 2JIA 2MSI 2MSJ 2SPG 3AME 3MSI 4AME 4MSI 5MSI 6AME 6MSI 7AME 7MSI 8AME 8MSI 9AME 9MSI |
| Descriptor | HPLC-12 TYPE III ANTIFREEZE PROTEIN, SULFATE ION (3 entities in total) |
| Functional Keywords | antifreeze protein, ocean pout, macrozoarces americanus, ice-binding protein |
| Biological source | MACROZOARCES AMERICANUS (OCEAN POUT) |
| Total number of polymer chains | 1 |
| Total formula weight | 7135.41 |
| Authors | Antson, A.A.,Smith, D.J.,Roper, D.I.,Lewis, S.,Caves, L.S.D.,Verma, C.S.,Buckley, S.L.,Lillford, P.J.,Hubbard, R.E. (deposition date: 2000-12-13, release date: 2001-01-31, Last modification date: 2023-12-13) |
| Primary citation | Antson, A.A.,Smith, D.J.,Roper, D.I.,Lewis, S.,Caves, L.S.D.,Verma, C.S.,Buckley, S.L.,Lillford, P.J.,Hubbard, R.E. Understanding the Mechanism of Ice Binding by Type III Antifreeze Protein J.Mol.Biol., 305:875-, 2001 Cited by PubMed Abstract: Type III antifreeze proteins (AFPs) are present in the body fluids of some polar fishes where they inhibit ice growth at subzero temperatures. Previous studies of the structure of type III AFP by NMR and X-ray identified a remarkably flat surface on the protein containing amino acids that were demonstrated to be important for interaction with ice by mutational studies. It was proposed that this protein surface binds onto the (1 0 [\bar 1] 0) plane of ice with the key amino acids interacting directly with the water molecules in the ice crystal. Here, we show that the mechanism of type III AFP interaction with ice crystals is more complex than that proposed previously. We report a high-resolution X-ray structure of type III AFP refined at 1.15 A resolution with individual anisotropic temperature factors. We report the results of ice-etching experiments that show a broad surface coverage, suggesting that type III AFP binds to a set of planes that are parallel with or inclined at a small angle to the crystallographic c-axis of the ice crystal. Our modelling studies, performed with the refined structure, confirm that type III AFP can make energetically favourable interactions with several ice surfaces. PubMed: 11162099DOI: 10.1006/JMBI.2000.4336 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.15 Å) |
Structure validation
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