New strategies for improving the biotechnological production of taxanes

Programa de Doctorat en Biotecnologia [eng] Plant specialized metabolism is the source of a wide range of bioactive compounds, some of which with relevant pharmacological properties. Nowadays, cancer is one of the main causes of mortality worldwide, therefore, the need to produce new compounds against cancer, in a biosustainable way, has become a challenge for plant biotechnology. In this scenario, our target is the biotechnological production of paclitaxel, a potent antineoplastic agent, in Taxus spp. cell biofactories. The goal of this PhD thesis is to build a scaffold of knowledge to deepen into the regulation, at the molecular and cellular level, of taxane biosynthesis, and thus contribute to a better understanding of the regulation of this metabolic pathway, especially those steps still unknown and those bottleneck enzymatic reactions that limit the production of paclitaxel. Board by board in the construction of this scaffold, our results have shown: (1) the synergistic effect of the combined elicitation strategy with coronatine and randomly methylated β-cyclodextrins significantly increases paclitaxel production up to 18-fold compared to control conditions; (2) we have also confirmed that cellular organelles known as lipid droplets are involved in the accumulation, storage, and trafficking of paclitaxel and related taxanes inside and outside Taxus cells; (3) we have corroborated that the putative TB506 hydroxylase is involved in the hydroxylation step at the C2' position of the taxane side chain, as demonstrated by in silico studies and biotransformation assays in protoplasts; (4) through metabolomic studies we have demonstrated the tight relationship that exists between taxane metabolism and other plant primary and specialized metabolic pathways under elicitation conditions; (5) in a circular economy environment, we have verified that taxane extraction residues are not waste, but a source of powerful antioxidants; (6) and finally, after addressing the challenge of the genetic transformation of Taxus spp., we have been able to confirm that metabolic engineering is a powerful tool for designing new Taxus cell lines optimized for paclitaxel production, which, combined with elicitation techniques, act synergistically to achieve production yields of this target compound of up to 300 mg/L in the new transgenic lines obtained. [spa] A partir del metabolismo especializado de las plantas se puede obtener una amplia gama de compuestos bioactivos, algunos de l