1J5B

Solution structure of a hydrophobic analogue of the winter flounder antifreeze protein

Replaces:  1K16

Summary for 1J5B

• Entry DOI: 10.2210/pdb1j5b/pdb
• NMR Information: BMRB: 5157
• Descriptor: Antifreeze protein type 1 analogue (1 entity in total)
• Functional Keywords: alpha helix, antifreeze protein
• Total number of polymer chains: 1
• Total formula weight: 3466.87

Authors

Liepinsh, E.,Otting, G.,Harding, M.M.,Ward, L.G.,Mackay, J.P.,Haymet, A.D. (deposition date: 2002-03-22, release date: 2002-03-27, Last modification date: 2024-11-13)

Primary citation

Liepinsh, E.,Otting, G.,Harding, M.M.,Ward, L.G.,Mackay, J.P.,Haymet, A.D.
Solution structure of a hydrophobic analogue of the winter flounder antifreeze protein.
Eur.J.Biochem., 269:1259-1266, 2002

PubMed Abstract: The solution structure of a synthetic mutant type I antifreeze protein (AFP I) was determined in aqueous solution at pH 7.0 using nuclear magnetic resonance (NMR) spectroscopy. The mutations comprised the replacement of the four Thr residues by Val and the introduction of two additional Lys-Glu salt bridges. The antifreeze activity of this mutant peptide, VVVV2KE, has been previously shown to be similar to that of the wild type protein, HPLC6 (defined here as TTTT). The solution structure reveals an alphahelix bent in the same direction as the more bent conformer of the published crystal structure of TTTT, while the side chain chi1 rotamers of VVVV2KE are similar to those of the straighter conformer in the crystal of TTTT. The Val side chains of VVVV2KE assume the same orientations as the Thr side chains of TTTT, confirming the conservative nature of this mutation. The combined data suggest that AFP I undergoes an equilibrium between straight and bent helices in solution, combined with independent equilibria between different side chain rotamers for some of the amino acid residues. The present study presents the first complete sequence-specific resonance assignments and the first complete solution structure determination by NMR of any AFP I protein.

PubMed: 11856360
DOI: 10.1046/j.1432-1033.2002.02766.x

Experimental method

SOLUTION NMR