Overcoming the plasticity of plant specialized metabolism for selective diterpene production in yeast

• Published in: Scientific reports Vol. 7; no. 1; pp. 8855 - 11
• Main Authors: Ignea, Codruta, Athanasakoglou, Anastasia, Andreadelli, Aggeliki, Apostolaki, Maria, Iakovides, Minas, Stephanou, Euripides G., Makris, Antonios M., Kampranis, Sotirios C.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 18.08.2017; Nature Publishing Group; Nature Portfolio
• Subjects: 631/449/2667; 631/61/318; Acids; Amino acid substitution; Biological activity; Biosynthesis; Carbohydrate Metabolism; Cytochrome P-450 Enzyme System - genetics; Diterpenes; Diterpenes - chemistry; Diterpenes - metabolism; Diterpenes, Abietane - biosynthesis; Genetic Engineering; Genetic Variation; Genotype; Humanities and Social Sciences; Metabolic engineering; Metabolic Networks and Pathways; Metabolism; Metabolites; multidisciplinary; Natural products; Plasticity; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Science; Science (multidisciplinary); Yeast; Yeasts - metabolism
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-09592-5

Plants synthesize numerous specialized metabolites (also termed natural products) to mediate dynamic interactions with their surroundings. The complexity of plant specialized metabolism is the result of an inherent biosynthetic plasticity rooted in the substrate and product promiscuity of the enzymes involved. The pathway of carnosic acid-related diterpenes in rosemary and sage involves promiscuous cytochrome P450s whose combined activity results in a multitude of structurally related compounds. Some of these minor products, such as pisiferic acid and salviol, have established bioactivity, but their limited availability prevents further evaluation. Reconstructing carnosic acid biosynthesis in yeast achieved significant titers of the main compound but could not specifically yield the minor products. Specific production of pisiferic acid and salviol was achieved by restricting the promiscuity of a key enzyme, CYP76AH24, through a single-residue substitution (F112L). Coupled with additional metabolic engineering interventions, overall improvements of 24 and 14-fold for pisiferic acid and salviol, respectively, were obtained. These results provide an example of how synthetic biology can help navigating the complex landscape of plant natural product biosynthesis to achieve heterologous production of useful minor metabolites. In the context of plant adaptation, these findings also suggest a molecular basis for the rapid evolution of terpene biosynthetic pathways.