msnA, a Stress Related Gene, is Required for Maintaining the Normal Oxidative State in Aspergillus parasiticus and Aspergillus flavus

L. L. Scharfenstein, Jr., P-K. Chang, L. Meng, N. Mahoney, R. J. Molyneux, J. Yu, R. L. Brown, B. C. Campbell

Author address: 

USDA, New Orleans, LA, USDA, Baton Rouge, LA, USDA, Albany, CA.


Saccharomyces cerevisiae MSN2 is necessary for yeast to cope with a broad range of stresses. Its orthologue in Aspergillus nidulans, nrdA, is required for normal asexual and sexual development. We investigate the role of msnA in growth, secondary metabolism and structural development for two species of Aspergillus that are major producers of aflatoxins. Disruption of msnA resulted in a much reduced colony diameter, a two-fold increase in conidiation and a loss of sclerotia production. Compared to the wild-type, 916;msnA mutants produced elevated levels of kojic acid, a phenolic compound, but aflatoxin production was not significantly affected. DNA microarray revealed an up-regulation of several oxidative stress response genes encoding cytochrome c peroxidase, superoxide dismutase and mycelial catalase in A. parasiticus 916;msnA mutants. The results suggest that msnA is required for the maintenance of the normal oxidative state in the fungal cells

abstract No: 


Full conference title: 

110th General Meeting American Society for Microbiology
    • ASM 110th (2010)