The parasitic fungus Claviceps purpurea has been used for decades by the pharmaceutical industry as a valuable producer of ergot alkaloids. As the biosynthetic pathway of ergot alkaloids involves a common precursor L-tryptophan, targeted genetic modification of the related genes may improve production yield. In this work, the S76L mutated version of the trpE gene encoding anthranilate synthase was constitutively overexpressed in the fungus with the aim of overcoming feedback inhibition of the native enzyme by an excess of tryptophan. In another approach, the dmaW gene encoding dimethylallyltryptophan synthase, which produces a key intermediate for the biosynthesis of ergot alkaloids, was also constitutively overexpressed. Each of the above manipulations led to a significant increase (up to 7-fold) in the production of ergot alkaloids in submerged cultures.

Department of Chemical Biology and Genetics Centre of the Region Haná for Biotechnological and Agricultural Research Palacký University Olomouc Šlechtitelů 27 Olomouc 783 71 Czech Republic

Department of Molecular Biology Centre of the Region Haná for Biotechnological and Agricultural Research Palacký University Olomouc Šlechtitelů 27 Olomouc 783 71 Czech Republic

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