Electrophysiological evidence for heptameric stoichiometry of ion channels formed by Staphylococcus aureus alpha-toxin in planar lipid bilayers

40Citations
Citations of this article
39Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Staphylococcal alpha-toxin forms homo-oligomeric channels in lipid bilayers and cell membranes. Here, we report that electrophysiological monitoring of single-channel function using a derivatized cysteine substitution mutant allows accurate determination of the subunit stoichiometry of the oligomer in situ. The electrophysiological phenotype of channels formed in planar lipid bilayers with the cysteine replacement mutant 17C is equal to that of the wild type. When pores were formed, with 17C, alterations of several channel properties were observed upon modification with SH reagents. Decreases in conductance then occurred that were seen only as negative voltage was applied. At the level of single channels, these were manifest as stepwise changes in conductance, each step most probably reflecting modification of a single SH group within the oligomer. Because seven steps were observed, the functional channel formed by alpha-toxin in planar lipid membranes is a heptamer.

Cite

CITATION STYLE

APA

Krasilnikov, O. V., Merzlyak, P. G., Yuldasheva, L. N., Rodrigues, C. G., Bhakdi, S., & Valeva, A. (2000). Electrophysiological evidence for heptameric stoichiometry of ion channels formed by Staphylococcus aureus alpha-toxin in planar lipid bilayers. Molecular Microbiology, 37(6), 1372–1378. https://doi.org/10.1046/j.1365-2958.2000.02080.x

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free