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

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Roles of peptide-peptide charge interaction and lipid phase separation in helix-helix association in lipid bilayer.
    Author: Shigematsu D, Matsutani M, Furuya T, Kiyota T, Lee S, Sugihara G, Yamashita S.
    Journal: Biochim Biophys Acta; 2002 Aug 19; 1564(1):271-80. PubMed ID: 12101022.
    Abstract:
    The roles of peptide-peptide charged interaction and lipid phase separation in helix-helix association in lipid bilayers were investigated using a model peptide, P(24), as a transmembrane alpha-helical peptide, and its four analogues. Fluorescence amino acids, tryptophan (P(24)W) and pyrenylalanine (P(24)Pya), were introduced into the sequence of P(24), respectively. Association of these peptides permits the resonance excitation energy transfer between tryptophan in P(24)W and pyrenylalanine in P(24)Pya or excimer formation between P(24)Pya themselves. To evaluate the effect of charged interaction on the association between alpha-helical transmembrane segments in membrane proteins, charged amino acids, glutamic acid (P(24)EW) and lysine (P(24)KPya), were introduced into P(24)W and P(24)Pya, respectively. Energy transfer experiments indicated that the charged interaction between the positive charge of lysine residue in P(24)KPya and the negative charge of glutamic acid residue in P(24)EW did not affect the aggregation of transmembrane peptides in lipid membranes. As the content ratio of sphingomyelin (SM) and cholesterol (Ch) was increased in the egg phosphatidylcholine (PC), the stronger excimer fluorescence spectra of P(24)Pya were observed, indicating that the co-existence of SM and Ch in PC liposomes, that is, the raft of SM and Ch, promotes the aggregation of the alpha-helical transmembrane peptides in lipid bilayers. Since the increase in the contents of SM and Ch leads to the decrease in the content of liquid crystalline-order phase, the moving area of transmembrane peptides might be limited in the liposomes, resulting in easy formation of the excimer in the presence of the lipid-raft.
    [Abstract] [Full Text] [Related] [New Search]