Isolation and Characterization of Mutants Affecting the Expression of the ACVS Gene in Aspergillus nidulans.

Joel Harper and Geoff Turner

Author address: 

Department of Molecular Biology and Biotechnology, University Of Sheffield, Sheffield SIO 2UH, England

Abstract: 

Joel Harper and Geoff Turner. Department of Molecular Biology and Biotechnology, University Of Sheffield, Sheffield SIO 2UH, England The expression of penicillin biosynthetic genes in Aspergillus nidulans has been examined by the use of the reporter genes lacZ and uidA which have been fused in frame to the promoters of the acvA and ipnA genes1 The acvA gene encodes for the enzyme -(L-( -aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) - and is the first of the three key enzymes responsible for penicillin production in Aspergillus nidulans. In an attempt to find regulatory genes affecting acvA expression, mutants of the strain carrying the acvA-lacZ fusion were produced by UV irradiation, and those that showed either an increased expression of lacZ or those showing a loss of expression were selected for further analysis. Mutants showing loss of -galactosidase activity were probed to check for the loss of the fusion gene, and those retaining the sequence were analyzed by sexual crosses. All mutations appeared to be linked to the fusion gene, and the promoter was sequenced to look for mutations. The mutants that displayed an increase in -galactosidase activity were crossed to establish the location of the mutation. Those showing a mutation not linked to the fusion gene were used to form diploids in an attempt to map the linkage group of the mutation, whilst those that showed linkage were sequenced to detect the position of the mutation. 1 Brakhage et al, 1992
1996

abstract No: 

NULL

Full conference title: 

3rd EUROPEAN CONFERENCE ON FUNGAL GENETICS
    • ECFG 3rd (1996)