Colicin K acts by forming voltage-dependent channels in phospholipid bilayer membranes

The bactericidal action of colicins K, E1, Ia, and other functionally related colicins involves disruption of active transport and leakage of ions from the cell. We show that a single colicin K molecule can form a voltage-dependent, relatively nonselective, ion-permeable channel of a few picosiemens...

Full description

Saved in:
Bibliographic Details
Published inNature (London) Vol. 276; no. 5684; p. 159
Main Authors Schein, S J, Kagan, B L, Finkelstein, A
Format Journal Article
LanguageEnglish
Published England 09.11.1978
Subjects
Biological Transport, Active - drug effects
Colicins - pharmacology
Electric Conductivity
Ion Channels - drug effects
Membrane Lipids
Membrane Potentials - drug effects
Membrane Proteins
Membranes, Artificial
Models, Biological
Phospholipids
Uncoupling Agents - pharmacology
Online AccessGet more information

Cover

More Information
Summary:The bactericidal action of colicins K, E1, Ia, and other functionally related colicins involves disruption of active transport and leakage of ions from the cell. We show that a single colicin K molecule can form a voltage-dependent, relatively nonselective, ion-permeable channel of a few picosiemens conductance in a planar phospholipid bilayer membrane. In a membrane containing many of these channels, the ratio of the number of conducting to nonconducting channels changes e-fold per 3.7 mV. We suggest that the physiological effects of colicin K and functionally related colicins result from their ability to form ion-permeable channels in the bacterial plasma membrane.
ISSN:0028-0836
DOI:10.1038/276159a0