These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: 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.
    Author: Rozek A, Buchko GW, Cushley RJ.
    Journal: Biochemistry; 1995 Jun 06; 34(22):7401-8. PubMed ID: 7779782.
    Abstract:
    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.
    [Abstract] [Full Text] [Related] [New Search]