Relationship between superoxide dismutase and melanin in a pathogenic fungus

Abstract

Since melanin is considered a virulence factor in Cryptococcus neoformans, its suppression at 37°C has been perplexing. We now show an opposite thermal regulation of superoxide dismutase (SOD), consistent with a compensatory mechanism. Moreover, we demonstrate normal SOD and catalase levels in albino, oxygen-sensitive mutants. These results suggest that melanin is an antioxidant factor comparable in importance to SOD.