Expression of the Escherichia coli β-glucuronidase gene in industrial and phytopathogenic filamentous fungi

Abstract

A chimaeric β-glucuronidase (GUS) gene has been created by ligating the Aspergillus nidulans glyceraldehyde 3-phosphate dehydrogenase promoter to the coding sequence of the E. coli uidA gene. Cotransformation of this vector into A. nidulans, A. niger and the tomato pathogen Fulvia fulva (syn. Cladosporium fulvum (Cooke)) resulted in the expression of β-glucuronidase. GUS activity was detected by growth on agar media containing X-gluc and by enzyme assays of mycelial extracts. Expression of the gene in F. fulva transformants was also easily detectable during growth in plants and did not affect pathogenicity. These results form the basis for a versatile and sensitive reporter gene system for industrial and phytopathogenic filamentous fungi.