Heteronuclear NMR studies of human serum apolipoprotein A-I. Part I. Secondary structure in lipid-mimetic solution.
The apolipoprotein A-I (apoA-I) solution structure in the presence of sodium dodecyl sulfate (SDS) was determined by combination of chemical shift index and torsion angle likelihood obtained from shift and sequence similarity methods. ApoA-I in lipid-mimetic solution is composed of alpha-helices (residues 8-32, 45-64, 67-77, 82-86, 90-97, 100-118, 122-140, 146-162, 167-205, 210-216 and 221-239), with 2-5 residue irregular segments between helical repeats, and the irregular segment 78-81 within helical repeat 2. ApoA-I is a monomer in the SDS complex and no evidence of interhelical interactions is found. Comparison of the apoA-I and apoA-I(1-186) [Okon et al., FEBS Lett. 487 (2001) 390-396] solution structures revealed that apoA-I undergoes a conformational change around Pro121.
Okon
Mark
M
Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada. mokon@chem.ubc.ca
Frank
Philippe G
PG
Marcel
Yves L
YL
Cushley
Robert J
RJ
D016632:Apolipoprotein A-I / Q000097:blood / Q000737:chemistry*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010446:Peptide Fragments / Q000737:chemistry*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*; D012996:Solutions
D016632:Apolipoprotein A-I; D010446:Peptide Fragments; D012996:Solutions; D012967:Sodium Dodecyl Sulfate