Effects of growth temperature on toxicity of T-2 toxin and roridin A to yeast.

In yeasts, growth temperature is known to affect the membrane phospholipid content. The effect of temperature on the growth inhibition of Kluyveromyces marxianus and Saccharomyces cerevisiae by the trichothecene mycotoxins, T-2 toxin and roridin A, was investigated. Examination of EC50 values for T-2 toxin and roridin A showed that these toxins were least inhibitory to both yeasts at 30 and 25 degrees C, respectively. Increasing or decreasing growth temperature from these temperatures gradually increased the inhibitory effect of the trichothecene mycotoxins. Temperature may affect the toxicity of the trichothecenes to the yeasts by regulating the composition of yeast cell membranes.