In vitro effects of listerial hemolysin on rat brain mitochondria.

Crude hemolysin derived from Listeria monocytogenes, strains 9-125 and 1122-3, reduced phosphate utilization of rat brain mitochondria in a succinate system. Oxidation rates were not altered by addition of hemolysin to a concentration of 42 hemolytic units/ml, with a mitochondrial protein concentration of 2.3 mg/ml. At a mitochondrial protein concentration of 1.8 mg/ml, 42 hemolytic units/ml of hemolysin increased the inhibition of phosphate utilization and also reduced the oxygen uptake. An age differential was apparent, with mitochondria from young rats demonstrating uncoupling at a lower concentration of hemolysin.