Mode of action of yeast killer toxins: channel formation in lipid bilayer membranes
Abstract
The toxic action of yeast killer proteins seems to involve selective functional damage to the plasma membrane of the sensitive cell. Physiological effects include leakage of K+ (refs 1, 2), inhibition of active transport of amino acids1,3 and acidification of the cell interior1,4. These effects are strikingly similar to the effects of certain bacterial colicins which have been demonstrated previously to form channels in membranes5. Proposed mechanisms of action have usually postulated a limited permeability change induced by the toxin in the plasma membrane1-4,6,7. We report here that a killer toxin from the yeast Pichia kluyveri forms ion-permeable channels in phospholipid bilayer membranes, and we propose that the in vitro electrophysiological properties of these channels account for the morbid effects observed in intoxicated cells. A preliminary account of this work has appeared elsewhere8.
- Publication:
-
Nature
- Pub Date:
- April 1983
- DOI:
- 10.1038/302709a0
- Bibcode:
- 1983Natur.302..709K