Engineering polar protein-based biomolecular condensates for modular biosynthesis

Microbiology has emerged as an environmentally friendly method for producing food ingredients, industrial chemicals, and pharmaceuticals. However, uncontrollable free-reacted enzymes induced the unwarranted accumulation of intermediates, resulting in low yields. In this study, we achieved spatial isolation of enzymatic reactions by engineering PodJ_IDR polar protein-based biomolecular condensates, thereby enhancing modular metabolic assembly to establish an efficient cascade catalytic system. These engineered condensates effectively recruit relevant enzymes through either short peptide pairing or direct fusion strategies to optimize catalytic performance. Furthermore, using the Lacto-N-tetraose (LNT) biosynthesis pathway as a representative model, we systematically refined the pathway modules by adjusting plasmid copy numbers. Finally, the potential of biomolecular condensates in multienzyme catalysis was validated. By anchoring key enzymes within the synthetic compartment, the production efficiency of LNT was significantly improved; compared with the wild-type and optimized free enzyme systems, the LNT yield was increased by 4.71-fold and 1.79-fold, respectively, with a simultaneous corresponding fold increase in metabolic flux. The findings indicated that various enzymes in the LNT cascade catalytic pathway were anchored within biomolecular condensates, with an improved LNT titer. This technique not only significantly enhances the efficiency of targeted metabolic pathways but also offers an efficient strategy for reinforcing metabolic flux regulation.