Bacteria photosensitized by intracellular gold nanoclusters for solar fuel production


The demand for renewable and sustainable fuel has prompted the rapid development of advanced nanotechnologies to effectively harness solar power. The construction of photosynthetic biohybrid systems (PBSs) aims to link preassembled biosynthetic pathways with inorganic light absorbers. This strategy inherits both the high light-harvesting efficiency of solid-state semiconductors and the superior catalytic performance of whole-cell microorganisms. Here, we introduce an intracellular, biocompatible light absorber, in the form of gold nanoclusters (AuNCs), to circumvent the sluggish kinetics of electron transfer for existing PBSs. Translocation of these AuNCs into non-photosynthetic bacteria enables photosynthesis of acetic acid from CO2. The AuNCs also serve as inhibitors of reactive oxygen species (ROS) to maintain high bacterium viability. With the dual advantages of light absorption and biocompatibility, this new generation of PBS can efficiently harvest sunlight and transfer photogenerated electrons to cellular metabolism, realizing CO2 fixation continuously over several days.

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Fig. 1: Schematic diagram of the M. thermoacetica/AuNC hybrid system.
Fig. 2: Microscopy images of the M. thermoacetica/AuNC hybrid system.
Fig. 3: Photosynthesis behaviour of different systems.
Fig. 4: Viability measurements.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.


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This work was supported by Director, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division, of the US Department of Energy under contract no. DE-AC02-05CH11231, FWP no. CH030201 (Catalysis Research Program). We thank the imaging facilities at the National Center for Electron Microscopy (NCEM) at the Molecular Foundry and the NMR facility of the College of Chemistry, University of California, Berkeley. Work at the NCEM was supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract no. DE-AC02-05CH11231. Research reported in this publication was supported in part by the National Institutes of Health S10 programme under award no. 1S10OD018136-01. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. H.Z. thanks the Suzhou Industry Park (SIP) fellowship.

Author information




H.Z., H.L. and P.Y. designed the studies and prepared the manuscript. H.L. synthesized the AuNCs. H.Z. and Z.T. cultured the bacteria and carried out all the photosynthesis experiments. H.L. and S.C.-B. repeated the photosynthesis experiments and confirmed the reproducibility. H.Z. performed the UV–vis absorption, SIM imaging and bacteria enumeration characterization. D.L. and H.Z. conducted photoluminescence emission spectrum measurements. Y.Y. conducted the HAADF-STEM characterization. S.C.-B. helped with the fluorescence reader for the ROS test. K.K.S. provided discussion. All authors discussed the results and commented on the manuscript.

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Correspondence to Peidong Yang.

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Supplementary Information

Supplementary Information

Supplementary Discussion, Supplementary Methods, Supplementary Figures 1–10, Supplementary Tables 1–4 and Supplementary References

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Supplementary Video 1

Video for intracellular AuNCs

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Zhang, H., Liu, H., Tian, Z. et al. Bacteria photosensitized by intracellular gold nanoclusters for solar fuel production. Nature Nanotech 13, 900–905 (2018).

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