Mutation profiling in differential diagnosis between TdT-positive high grade/large B-cell

ABSTRACT

Sustainable valorization of crude glycerol, a major biodiesel byproduct, into high-value chemicals remains a key challenge for biorefineries. Here, we report the first systematic metabolic engineering of Lentilactobacillus diolivorans to enable cost-effective, vitamin B12-independent production of 1,3-propanediol (1,3-PDO) directly from biodiesel waste. We constructed a B12-independent production host (Lac/4) by enhancing glycerol uptake, boosting 1,3-PDO oxidoreductase (PDOR) activity, and introducing a B12-independent glycerol dehydration pathway. Optimization of two-stage whole-cell biotransformation process boosted the 1,3-PDO titer from 6.1 to 18.0 g/L while eliminating the need for B12. To overcome residual 3-hydroxypropionaldehyde (3-HPA) accumulation, we developed a two-module synthetic consortium by combining the Lac/4 strain (Module I) with PDOR-overexpressing Escherichia coli strains (Module II). With the best Module II strain overexpressing Clostridium pasteurianum PDOR and the optimized Module I:II mass ratio of 1:1, we achieved 28.8 g/L of 1,3-PDO with minimal 3-HPA. Equipping the best Module II strain with an aldehyde dehydrogenase (GabD4_E209Q/E269Q) for in situ NADH regeneration further raised 1,3-PDO titer to 32.9 g/L. The process scaled robustly in 5-L bioreactors in batch mode, achieving 1,3-PDO titer and substrate conversion of 38.8 g/L and 93.9% with pure glycerol, and 35.9 g/L and 86.9% with crude glycerol. This integrated strategy establishes an efficient, economical route for biodiesel waste valorization to 1,3-PDO and positions L. diolivorans as an amenable-to-engineering and scalable production host for industrial bioprocessing.