Evidence for three differentially regulated catalase genes in Neurospora crassa: effects of oxidative stress, heat shock, and development.

摘要: Genetic and biochemical studies demonstrated that Neurospora crassa possesses three catalases encoded by separate structural genes. The specific activities of the enzymes varied in response to superoxide-mediated stress, heat shock, development. loci, which we designated cat-1, cat-2, cat-3, map right arms chromosomes III, VII, respectively. cat-1-encoded enzyme (designated Cat-1; estimated molecular weight, 315,000; pI 5.2) was predominant catalase rapid-growth mycelium, its activity substantially increased paraquat-treated heat-shocked mycelium. Cat-2 (Mw, 165,000; 5.4) absent from mycelium but present at low levels conidia stationary-phase It extracts derived had been shocked for 2 h. Cat-3 340,000; 5.5) mature conidia.