Applied and Investigative uses of Recombinant DNA Techniques for Filamentous Fungal Products

The use of Recombinant DNA techniques applied to filamentous fungi and their products is reviewed. However the principal objective of the research described below has been to elucidate the mechanisms which govern the regulation of penicillin biosynthesis in Penicillium chrysogenum. In this respect work from the authors and other laboratories is described. The application of recombinant DNA technology is leading to a steady increase in our level of understanding of the underlying genetic and biochemical base for high penicillin yields. For example, the use of DNA probes has shown that high yielding strains have multiple copies of the penicillin biosynthetic genes (pen genes) yet still share a regulatory system in common with the original low titre progenitor strain NRRL 1951. In addition it has now proven possible to devise assays specific for proteins which interact with the regulatory sequences of the pen genes. Knowledge gained with this important secondary metabolite can give valuable guidance in constructing strategies for the discovery and increase in yield of other important metabolites.