Tolaasin, a toxic secretion by Pseudomonas tolaasii, is the cause of bacterial brown blotch disease of edible mushrooms.
In addition to forming an amphipathic left handed alpha-helix in a hydrophobic environment,[4] the toxin has been shown to form Zn2+-sensitive voltage-gated ion channels in planar lipid bilayers and to catalyze erythrocyte lysis by a colloid osmotic mechanism.
[5] At high concentrations, tolaasin acts as a detergent that is able to directly dissolve eukaryotic membranes.
[3] Tolaasin pores disrupt the cellular osmotic pressure, leading to membrane collapse.
Tolaasin cytotoxicity can be effectively inhibited by food detergents, as well as sucrose and polyglycerol esters of fatty acids.