One of the grand themes in the field of synthetic biology is the promise of the development of the tools that will help facilitate the global transition towards a renewable and sustainable bio-based economy. One such step towards that sustainable future is the use of microbial cell factories for the production of active pharmaceutical ingredients and nutraceuticals. In this line, the commercial production of the ergot alkaloids and their semi-synthetic derivatives is one such avenue that is appropriately poised to be improved on by being produced by microbial cell factories.
Ergot alkaloids have throughout history been known for their potent biological effects. These properties have been extensively exploited in the development of the semi-synthetic derivatives that are used in the treatments for Parkinsonism and dementia, amongst many others. Their production, however, is limited by the difficulty in the cultivation of the parasitic ergot fungi.
This thesis thus describes the progressive effort made to heterologously reconstitute the ergot alkaloid pathway to the main ergoline therapeutic precursor, D-lysergic acid, in Saccharomyces cerevisiae. Fundamental to this work is the adaptation of a Golden Gate-based cloning methodology, which would enable the easy and rapid assembly of customizable expression cassettes, and that is compatible with automation. Finally, this work presents for the first time, the development of a prototype yeast strain that before any extensive strain or bioprocess optimization, is capable of producing up to 71.5 μg/L of D-lysergic acid. This demonstration lays the groundwork for a more efficient commercial production method, as well as a platform for the discovery of novel ergot alkaloid therapeutics.