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: How can the aromatic side-chains modulate the conductance of the gramicidin channel? A new approach using non-coded amino acids.
    Author: Daumas P, Benamar D, Heitz F, Ranjalahy-Rasoloarijao L, Mouden R, Lazaro R, Pullman A.
    Journal: Int J Pept Protein Res; 1991 Sep; 38(3):218-28. PubMed ID: 1722196.
    Abstract:
    In order to elucidate the role of the aromatic side-chains in the mechanism of transduction of monovalent cations through the channel of linear gramicidin, two series of analogues containing non-coded aromatic amino acids were synthesized. In the first series, the four tryptophans were replaced by either four L-3-(8-quinolyl)alanyl or four L-3-(4-quinolyl)alanyl residues and single channel conductance measurements showed that these substitutions led to a strong lowering of the channel conductance, which is attributed to a modification of the orientation of the aromatic side-chains due to an increase of their hydrophobicity. In the second series, the analogues contained both tryptophyl and naphthylalanyl residues in various amounts and positions. The single channel conductance data indicated that the conductance was mainly governed by the number of polar residues (Trp) and not by their positions. The conformational consequences of these results are discussed together with their influence on the energy profile of the gramicidin channel.
    [Abstract] [Full Text] [Related] [New Search]