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1ale
From Proteopedia
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CONFORMATION OF TWO PEPTIDES CORRESPONDING TO HUMAN APOLIPOPROTEIN C-I RESIDUES 7-24 AND 35-53 IN THE PRESENCE OF SODIUM DODECYLSULFATE BY CD AND NMR SPECTROSCOPY
Overview
Peptides corresponding to the proposed lipid-binding domains of human, apolipoprotein C-I, residues 7-24 (ALDKLKEFGNTLEDKARE) and 35-53, (SAKMREWFSETFQKVKEKL), were studied by CD and two-dimensional 1H NMR, spectroscopy. Sodium dodecyl sulfate (SDS) was used to model the, lipoprotein environment. Analysis of the CD data shows that both peptides, lack well-defined structure in aqueous solution but adopt helical, ordered, structures upon the addition of SDS. The helical nature of the peptides in, the presence of SDS was confirmed by H alpha secondary shifts. A total of, 199 (apoC-I(7-24)) and 266 (apoC-I(35-53)) distance restraints were used, in distance geometry and simulated annealing calculations to generate, average structures for both peptides in aqueous solutions containing SDS., The backbone (N, C alpha, C = O) RMSD from the average structure of an, ensemble of 20 structures was 0.73 +/- 0.22 and 0.48 +/- 0.14 A for, apoC-I(7-24) and apoC-I(35-53), respectively. In the presence of SDS, the, distance geometry and simulated annealing calculations show that both, peptides adopt well-defined amphipathic helices with distinct hydrophobic, and hydrophilic faces. The calculated structures are discussed relative to, predicted structures. Comparing our CD and NMR results for the apoC-I, fragments in SDS with CD results of others obtained in the presence of, dimyristoylphosphatidylcholine indicates that SDS may be a better model of, the lipoprotein environment.
About this Structure
1ALE is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Conformation of two peptides corresponding to human apolipoprotein C-I residues 7-24 and 35-53 in the presence of sodium dodecyl sulfate by CD and NMR spectroscopy., Rozek A, Buchko GW, Cushley RJ, Biochemistry. 1995 Jun 6;34(22):7401-8. PMID:7779782
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