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A cell-free protein-producing gel

Abstract

Proteins are important biomaterials and are generally produced in living cells. Here, we show a novel DNA hydrogel that is capable of producing functional proteins without any living cells. This protein-producing gel (termed ‘the P-gel system’ or ‘P-gel’) consists of genes as part of the gel scaffolding. This is the first time that a hydrogel has been used to produce proteins. The efficiency was about 300 times higher than current, solution-based systems. In terms of volumetric yield, the P-gel produced up to 5 mg ml−1 of functional proteins. The mechanisms behind the high efficiency and yield include improved gene stability, higher local concentration and a faster enzyme turnover rate due to a closer proximity of genes. We have tested a total of 16 different P-gels and have successfully produced all 16 proteins including membrane and toxic proteins, demonstrating that the P-gel system can serve as a general protein production technology.

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Figure 1: Fabrication of P-gel micropads.
Figure 2: Functional Rluc expression from P-gel with different parameters.
Figure 3: Comparison of the proteins expressed from P-gel and SPS.
Figure 4: Mechanism studies of P-gel expression.

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Acknowledgements

The work is partially supported by NYSTAR Faculty Development Program Award, NYSTAR CAT grant, US National Science Foundation’s CAREER award (grant number: 0547330) and a USDA NRI grant. We wish to acknowledge L. Ding, M.R. Hartman, S. Y. Kwon, S. Tan and C. Umbach for technical support and helpful discussions. The authors also thank M. J. Campolongo, J. C. March, J. Kahn, E. J. Rice and T. Tran for proofreading this manuscript.

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Authors and Affiliations

Authors

Contributions

N.P., S.H.U. and D.L. conceived and designed the experiments. N.P., S.H.U., H.F. and J.X. carried out the experiments. N.P., S.H.U. and D.L. analysed the data. N.P., S.H.U., H.F., J.X. and D.L. co-wrote the paper. All authors discussed the results and commented on the manuscript.

Corresponding authors

Correspondence to Nokyoung Park, Soong Ho Um, Jianfeng Xu or Dan Luo.

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Competing interests

Patents related to the P-gel system have been licensed to a start-up company, DNANO systems, LLC; D. Luo is a co-founder of this company. Cornell University is the owner of the patents.

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Park, N., Um, S., Funabashi, H. et al. A cell-free protein-producing gel. Nature Mater 8, 432–437 (2009). https://doi.org/10.1038/nmat2419

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