A 1H-NMR determination of the solution structure of the A-chain of insulin: comparison with the crystal structure and an examination of the role of solvent.
The 1H-NMR chemical shift assignments for the oxidized A-chain of bovine insulin have been determined in aqueous and 30% trifluoroethanol/water solutions. Analysis of the observed medium-range nuclear Overhauser effects indicates that in aqueous solution significant populations of the peptide exist, with a 3(10)-helical conformation over residues 12-17. This region corresponds to helix A (13-20) in the crystal structure of the 2 Zn insulin hexamer. In 30% TFE solution, the NOE data are supportive of a random coil conformation throughout the peptide.
Hawkins
B L
BL
Victorian College of Pharmacy, Monash University, Parkville, Australia.
Cross
K J
KJ
Craik
D J
DJ
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D003460:Crystallization; D006863:Hydrogen-Ion Concentration; D007328:Insulin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D012996:Solutions; D012997:Solvents; D014270:Trifluoroethanol
D007328:Insulin; D012996:Solutions; D012997:Solvents; D014270:Trifluoroethanol