Voltage-Dependent Formation of Anion Channels by Synthetic Rigid-Rod Push-Pull ß-Barrels

Article Article scientifique Article Voltage-Dependent Formation of Anion Channels by Synthetic Rigid-Rod Push-Pull ß-Barrels eng 2003 author Sakai Naomi 131140 author Houdebert David 505280 author Matile Stefan 129654 223-232 10.1002/chem.200390016 12506379 0947-6539 Ion channels formed by p-octiphenyls equipped with amphiphilic, cationic tripeptide strands and either with (5) or without (6) axial dipole moment are described (preliminary communication: N. Sakai, S. Matile, J. Am. Chem. Soc. 2002, 124, 1184-1185). Fluorescence kinetics with variably polarized neutral or anionic vesicles, together with planar bilayer conductance measurements, reveal voltage dependence with weakly lyotropic anion selectivity, and deactivation by competing surface potentials of the ion channels formed by asymmetric 5. In planar bilayers, 5 forms short-lived, poorly organized channels--similar to those produced by alpha-helical natural antibiotics--capable of transforming into stable, ohmic p-octiphenyl "beta-barrel" ion channels similar to those of the >99 % homologous but symmetric 6. Fluorescence depth quenching and circular dichroism studies confirm the effect of membrane potentials in promotion of the partitioning of 5 (but not 6) into the bilayers, identifying partitioning as the voltage-dependent step. Antibiotics Ion channels Membrane potential Molecular recognition Supramolecular chemistry Dewey 540 36 Département de chimie organique 141 false Chemistry 9 1 cf4bf78d-29bf-4b27-8e5e-668a69205dda Article Restricted file1.pdf 280864 application/pdf restrictedAccess Faculté des sciences / Section de chimie et biochimie / Département de chimie organique

Title	Published in	Access level	OA Policy	Year	Views	Downloads

Voltage-Dependent Formation of Anion Channels by Synthetic Rigid-Rod Push-Pull ß-Barrels	Chemistry			2003	440	0

Archive ouverte UNIGE

Houdebert, David