The oxidant function of pro-apoptotic protein Bax was investigated through heterologous expression in yeast. Direct measurements of fatty acid content show that Bax-expression induces oxidation of mitochondrial lipids. This effect is prevented by the coexpression of Bcl-xL. The oxi-dation actually could be followed on isolated mitochondria as respiration-induced peroxidation of polyunsaturatedcis-parinaric acid and on whole cells as the increase in the amount of thiobarbituric acid-reactiveproducts. .
