Xian-Hao Xu

Spatiotemporal Metabolic Regulation for Programmable Microbial Cell Factories.

De novo L-(+)-tartaric acid biosynthesis in multi-modular engineered yeasts

L-(+)-tartaric acid (L-TA) is a high-value chiral organic acid essential for food and pharmaceuticals. Despite its industrial importance, sustainable green production is constrained by the lack of a fully defined biosynthetic pathway. Here, we report the de novo biosynthesis of L-TA in Saccharomyces cerevisiae through...

Plasmid- and Inducer-Free Biosynthesis of Difucosyllactose through Rational Fusion Enzyme Engineering and Systematic Pathway Optimization.

Difucosyllactose (DFL), a fucosylated human milk oligosaccharide, exhibits significant application potential in the food and pharmaceutical industries. However, the microbial production of DFL faces challenges such as the accumulation of the intermediate 2'-fucosyllactose (2'-FL) and the high costs associated with the...

Computationally Guided Engineering of Multi-Enzyme Cascades Enables Efficient Trehalose Biosynthesis.

Trehalose is a nonreducing disaccharide widely used for its biomolecule-protective properties. However, multienzyme cascade production remains limited by low enzyme expression and suboptimal catalytic performance. To address this, thermostable maltooligosyltrehalose synthase (TreY) and trehalohydrolase (TreZ) from Arth...

Mechanism-Guided Synergistic Engineering of Substrate Access and Catalytic Microenvironment in Oxidosqualene Cyclase for Enhanced Amyrin Biosynthesis.

Oxidosqualene cyclases (OSCs) catalyze the cyclization of 2,3-oxidosqualene into diverse triterpenoids, yet their intrinsically low catalytic efficiency restricts biosynthetic productivity. Here, we establish a mechanism-guided synergistic engineering strategy that extends beyond conventional active-site engineering by...