The Influence of Varied Amide Bond Positions on Hydraphile Ion Channel Activity.
Hydraphile compounds have been prepared in which certain of the amine nitrogens have been replaced by amide residues. The amide bonds are present either in the sidearm, the side chain, or the central relay. Sodium cation transport through phospholipid vesicles mediated by each hydraphile was assessed. All of the amide-containing hydraphiles showed increased levels of Na(+) transport compared to the parent compound, but the most dramatic rate increase was observed for sidearm amine to amide replacement. We attribute this enhancement to stabilization of the sidearm in the bilayer to achieve a better conformation for ion conduction. Biological studies of the amide hydraphiles with E. coli and B. subtilis showed significant toxicity only with the latter. Further, the consistency between the efficacies of ion transport and toxicity previously observed for non-amidic hydraphiles was not in evidence.
Weber
Michelle E
ME
Department of Molecular Biology & Pharmacology, Washington University School of Medicine, Campus Box 8103, 660 S. Euclid Ave., St. Louis, MO 63110 USA; E-mail: ggokel@molecool.wustl.edu.
Wang
Wei
W
Steinhardt
Sarah E
SE
Gokel
Michael R
MR
Leevy
W Matthew
WM
Gokel
George W
GW