Metabolic Enginnering of Yeast for Production of Medicinal Triterpenoids Maslinic Acid and Corosolic Acid | AIChE

Metabolic Enginnering of Yeast for Production of Medicinal Triterpenoids Maslinic Acid and Corosolic Acid

Authors 

Dai, Z. - Presenter, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences

Maslinic acid and corosolic acid produced by the medicinal plants have diverse biological activities, including antibacterial, anti-human immunodeficiency virus (HIV) and/or antitumor activities. Here, we identified the synthetic pathways of maslinic acid and corosolic acid, and produced these triterpenoids from sugars by metabolically engineered yeasts. Firstly, 99 candidate P450 genes were obtained by transcriptome sequencing of methyl jasmonate-induced Crataegus pinnatifida cells, which were then screened in Saccharomyces cerevisiae platform strain producing oleanolic acid. A cytochrome P450 gene MAA45, which could catalyze the C-2a oxidation of oleanolic acid, was identified by LC-MS and NMR analysis. This gene was also evaluated for its potential oxidizing activities in S. cerevisiae platform strain producing ursolic acid, and was shown to have the ability to generate corosolic acid. MAA45 was characterized as a multifunctional enzyme with oleanane- and ursane-type triterpenoids 2a-oxidase activities. In addition, S. cerevisiae cell factory BY-T30-OA was engineered to produce sufficient amounts of metabolic precursors (oleanolic acid and ursolic acid), and the MAA45 gene was integrated into this platform strain to improve the production of targeted triterpenoids. These findings will be useful in the heterologous production of pharmacologically and industrially important triterpenoids, including maslinic acid and corosolic acid.