The ura5 gene of the filamentous fungus Podospora anserina: nucleotide sequence and expression in transformed strains.

We have sequenced the ura5 gene of the filamentous fungus Podospora anserina. The deduced sequence for the orotidylic acid pyrophosphorylase (OMPppase) has been compared with the Escherichia coli enzyme which is the only known sequence for this enzyme. This comparison shows extensive blocks of homology. The expression of the ura5 gene has been studied in a ura5 mutant which has been transformed by a recombinant plasmid carrying the ura5 gene. We observed that strains carrying integrated multicopies of the transforming vector exhibit higher specific activity for OMPppase than wild type (wt). By recombination we have constructed a strain in which the level of this enzyme is 32 times higher than in the wt strain.