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bioRxiv · 10.1101/2025.04.13.648562

Modular Engineering of Escherichia coli for Enhanced Nickel Uptake, Survival, Biomineralization, and Hydrogen-Supported Bioremediation

Shi, Y.·Ma, R.·Qi, L.·Tan, X.·Chen, L.·Wang, Y.·Huang, K.·Suo, Z.·Li, Y.·Chen, H.·Chen, Z.·Chen, X.·Li, W.·Zhen, K.
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Abstract

Nickel contamination poses increasing environmental and industrial challenges, demanding effective and sustainable remediation strategies. Here, we present a modular synthetic biology approach to engineer Escherichia coli for efficient nickel enrichment, resilience in toxic environments, intracellular biomineralization, and hydrogen-based co-culture stability. Our system comprises four functional modules: (1) a nickel enrichment module, in which the fusion protein NixA-F1v outperformed existing uptake systems, and a mutant repressor RcnRC35L enhanced retention by suppressing nickel efflux; (2) a survival module where heterologous expression of Helicobacter pylori Hpn conferred tolerance to high nickel concentrations, and YejM increased phage resistance; (3) a nickel microparticle module enabling intracellular bioconversion of nickel into detectable microparticles even without engineered uptake proteins; and (4) a hydrogen supply module supporting co-culture stability through E. coli-cyanobacteria adhesion for sustained hydrogen production. These modules were experimentally validated through comparative uptake assays, survival profiling, and microscopy-based particle detection. Our findings demonstrate a customizable and integrative microbial platform for metal bioremediation and biosensing, with potential applications in environmental engineering and industrial waste treatment.

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Shi, Y., Ma, R., Qi, L., Tan, X., Chen, L., Wang, Y., Huang, K., Suo, Z., Li, Y., Chen, H., Chen, Z., Chen, X., Li, W., Zhen, K.. 2025-04-13. Modular Engineering of Escherichia coli for Enhanced Nickel Uptake, Survival, Biomineralization, and Hydrogen-Supported Bioremediation. https://doi.org/10.1101/2025.04.13.648562

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