Steviol-13-O-glucoside(13-SMG),a key diterpenoid precursor controlling the biosynthesis of steviol glycosides,currently faces production bottlenecks due to an insufficient precursor supply for the MVA pathway,low cata...Steviol-13-O-glucoside(13-SMG),a key diterpenoid precursor controlling the biosynthesis of steviol glycosides,currently faces production bottlenecks due to an insufficient precursor supply for the MVA pathway,low cata-lytic efficiency of the native glycosyltransferase UGT85C2,degradation by endogenous glycoside hydrolases,and limited functional expression of P450 enzymes because of the inadequate microenvironment of the endoplasmic reticulum(ER).This study achieved de novo biosynthesis of 13-SMG in Saccharomyces cerevisiae through a sys-tematic engineering strategy encompassing MVA pathway enhancement,semi-rational modification of UGT85C2,disruption of competing hydrolases,and optimization of the ER microenvironment.These strategies resulted in the construction of a highly efficient S.cerevisiae strain for production of 13-SMG,which achieved a titer of 1.3 g/L fermentation in a 5-L bioreactor,thereby establishing a foundation for green and sustainable industrial-scale production of high-value natural sweeteners.展开更多
基金supported by the National Key Research and Development Program of China(2024YFF1106400).
文摘Steviol-13-O-glucoside(13-SMG),a key diterpenoid precursor controlling the biosynthesis of steviol glycosides,currently faces production bottlenecks due to an insufficient precursor supply for the MVA pathway,low cata-lytic efficiency of the native glycosyltransferase UGT85C2,degradation by endogenous glycoside hydrolases,and limited functional expression of P450 enzymes because of the inadequate microenvironment of the endoplasmic reticulum(ER).This study achieved de novo biosynthesis of 13-SMG in Saccharomyces cerevisiae through a sys-tematic engineering strategy encompassing MVA pathway enhancement,semi-rational modification of UGT85C2,disruption of competing hydrolases,and optimization of the ER microenvironment.These strategies resulted in the construction of a highly efficient S.cerevisiae strain for production of 13-SMG,which achieved a titer of 1.3 g/L fermentation in a 5-L bioreactor,thereby establishing a foundation for green and sustainable industrial-scale production of high-value natural sweeteners.
