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Abstract Proliferation of multidrug-resistant (MDR) bacteria poses a threat to human health, requiring new strategies. Here we propose using fitness neutral gene expression perturbations to potentiate antibiotics. We systematically explored 270 gene knockout-antibiotic combinations inEscherichia coli, identifying 90 synergistic interactions. Identified gene targets were subsequently tested for antibiotic synergy on the transcriptomic level via multiplexed CRISPR-dCas9 and showed successful sensitization ofE. coliwithout a separate fitness cost. These fitness neutral gene perturbations worked as co-therapies in reducing aSalmonella entericaintracellular infection in HeLa. Finally, these results informed the design of four antisense peptide nucleic acid (PNA) co-therapies,csgD,fnr,recAandacrA, against four MDR, clinically isolated bacteria. PNA combined with sub-minimal inhibitory concentrations of trimethoprim against two isolates ofKlebsiella pneumoniaeandE. colishowed three cases of re-sensitization with minimal fitness impacts. Our results highlight a promising approach for extending the utility of current antibiotics. 

Abstract Enzymatic Fisher‐Tropsch (FT) process catalyzed by vanadium (V)‐nitrogenase can convert carbon monoxide (CO) to longer‐chain hydrocarbons (>C2) under ambient conditions, although this process requires high‐cost reducing agent(s) and/or the ATP‐dependent reductase as electron and energy sources. Using visible light‐activated CdS@ZnS (CZS) core‐shell quantum dots (QDs) as alternative reducing equivalent for the catalytic component (VFe protein) of V‐nitrogenase, we first report a CZS : VFe biohybrid system that enables effective photo‐enzymatic C−C coupling reactions, hydrogenating CO into hydrocarbon fuels (up to C4) that can be hardly achieved with conventional inorganic photocatalysts. Surface ligand engineering optimizes molecular and opto‐electronic coupling between QDs and the VFe protein, realizing high efficiency (internal quantum yield >56 %), ATP‐independent, photon‐to‐fuel production, achieving an electron turnover number of >900, that is 72 % compared to the natural ATP‐coupled transformation of CO into hydrocarbons by V‐nitrogenase. The selectivity of products can be controlled by irradiation conditions, with higher photon flux favoring (longer‐chain) hydrocarbon generation. The CZS : VFe biohybrids not only can find applications in industrial CO removal for high‐value‐added chemical production by using the cheap, renewable solar energy, but also will inspire related research interests in understanding the molecular and electronic processes in photo‐biocatalytic systems.