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bioRxiv · 10.1101/2025.05.20.655217

Engineering orthogonal and synergistic modules in marine bacteria for efficient upcycling of lignin-derived carbon

Wei, Y.·Gong, B.·Chen, P.-R.·Yuan, X.-Z.·Wang, S.-G.·Xia, P.-F.
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Abstract

Reverting waste carbon into chemicals and materials with minimal freshwater reliance is essential for a sustainable future. Here, we report the establishment of a blue biological scheme by repurposing the evolutionary fitness of marine bacterium Roseovarius nubinhibens for efficient conversion of lignin-derived carbon into valuable chemicals with seawater as a water source. We created independency of the superior catalytic capacity of R. nubinhibens to circumvent a rare polar effect, and genetically decoupled the bioproduction pathway from central metabolism, channeling all lignin-derived carbon into desired products. Next, an orthogonal growth module was generated with acetate as a second carbon source, which is a ubiquitous byproduct and inhibitor in plant biomass hydrolysis, to sustain cell growth and supply necessary resources, but not substrates, for the growth-coupled bioproduction. Besides this designed metabolic segregation, we identified a cross-module push-and-pull synergy between bioproduction and cell growth, enabling enhanced performance and robustness. By deploying this biological scheme, we successfully achieved escalated conversion of the lignin-derived monomer 4-hydroxybenzoate to value-added compounds protocatechuate and {beta}-ketoadipate with seawater, rather than freshwater, as the water source, generating a distinct blue biological scheme with potentials in simultaneous carbon and water conservation.

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Wei, Y., Gong, B., Chen, P.-R., Yuan, X.-Z., Wang, S.-G., Xia, P.-F.. 2025-05-25. Engineering orthogonal and synergistic modules in marine bacteria for efficient upcycling of lignin-derived carbon. https://doi.org/10.1101/2025.05.20.655217

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