Establishing Vibrio natriegens as a high-performance host for acetate-based poly-3-hydroxybutyrate production

Acetate can be a sustainable and renewable carbon source that holds significant promise for biotechnological production but is underutilized industrially due to limited microbial efficiency. Vibrio natriegens, recognized for exceptionally fast growth rates, represents a compelling host for developing efficient acetate-based bioprocesses. In this study, adaptive laboratory evolution significantly enhanced V. natriegens' ability to grow on acetate as the sole carbon source, achieving an 89 % increase in growth rate. Genetic and transcriptomic analyses revealed key adaptations improving acetate uptake and metabolism via increased salt tolerance, boosted Pta/AckA pathway activity, and rewired quorum sensing. Further metabolic engineering and bioprocess optimization enabled the evolved strain to reach high cell densities and efficiently convert acetate into the bioplastic poly-3-hydroxybutyrate (PHB), with productivities up to 0.27 g/L/h and PHB accumulation reaching 45.66 % of cell biomass. These advances position V. natriegens as a highly promising microbial platform for sustainable, scalable, and cost-effective biomanufacturing using acetate as a green feedstock.