Abstract
Investigation was made on the properties of a hemolytic toxin isolated from the culture filtrate of the Link strain of Aspergillus flavus. The molecular weight of this toxin was estimated to be approximately 10, 000 by gel filtration, and its isoelectric point around pH 4.5 by the ampholine-electrofocusing method. It was stable in a pH range from 4 to 8, and unstable below pH 3 and above pH 9. The preparation was stable to heat-treatment up to 38C at pH 6.0 for 1 hour. Most of its activity was lost after heating at about 55C under the same conditions.
The hemolytic activity was activated by the addition of cholesterol or G-strophanthin. It was inhibited slightly by gangliosides and ZnCl2, and remarkably by HgCl2 and iodine. The oxidative phosphorylation in vitro of renal mitochondria from mice was inhibited by a high concentration (500μg/0.1ml) of the hemolytic toxin. This toxin induced moderate azotemia in mice in which the NPN value was 145-160mg/dl 12-24 hours after intravenous injection with 1mg of the toxin.
