Abstract
Rapid and in-depth exploration of the chemical space of high-molecular-weight synthetic polypeptides via ring-opening polymerization of N-carboxyanhydride allows the discovery of protein mimics and functional biomaterials. The traditional synthetic workflow, however, is labour intensive and has limited throughput. Here we develop an approach for the high-throughput diversification of polypeptides based on a click-like reaction between selenolate and various electrophiles in aqueous solutions. Importantly, the platform is amenable to automation, which allows rapid generation of up to 1,200 homopolypeptides or random heteropolypeptides (RHPs) within one day. With the assistance of machine learning, iterative exploration of the RHP library identifies candidates with improved glutathione peroxidase-like activity from the complex chemical space of which we have little previous knowledge. This automated and high-throughput platform provides potential solutions to unmet challenges, such as the de novo design of artificial enzymes, biomacromolecule delivery and understanding of intrinsically disordered proteins.
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Data availability
All of the data generated or analysed in this study are included in this published article and its Supplementary Information files. Source data are provided with this paper.
Code availability
The code for the generation of random RHPs and Bayesian optimization in this study is included in Supplementary Code 1.
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Acknowledgements
This work was supported by the National Key Research and Development Program of China (2019YFA0904203 to H.L.), National Natural Science Foundation of China (22125101 and 21975004 to H.L. and 22105008 to G.W.) and Beijing Natural Science Foundation (2220023 to H.L.), a fellowship of the China Postdoctoral Science Foundation (2020M680192 to G.W.) and the Li Ge-Zhao Ning Life Science Youth Research Foundation (LGZNQN202206 to H.L.). G.W. thanks the Boya Postdoctoral Fellowship of Peking University for financial support. G.W. thanks S. Goldman (Department of Chemical Engineering, Massachusetts Institute of Technology) and Z. Wang (Department of Industrial Engineering, Tsinghua University) for the discussion and R. Mercado (Department of Chemical Engineering, Massachusetts Institute of Technology) for examining the code. Figure 5a and graphical abstract created with BioRender.com.
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G.W. and H.L. designed and directed the research. G.W., Z.-Y.T., X.L. and S.W. performed the synthesis of monomers and the precursor polypeptide. G.W. and H.Z. built and validated the HTS and characterization platform and performed the screening of GPx mimics. G.W. and J.Z. wrote the code of Bayesian optimization. G.W., C.W.C. and H.L. wrote the original draft. All authors reviewed and accepted the manuscript.
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Nature Synthesis thanks Adam Gormley, Michael Webb and Huaping Xu for their contribution to the peer review of this work. Primary Handling Editor: Peter Seavill, in collaboration with the Nature Synthesis team.
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Supplementary Information
Experimental details and Supplementary Figs. 1–68 and Tables 1–4.
Supplementary Code 1
Source code (BO_GPx_Ax022.ipynb) for Bayesian optimization with the example input and output files, as well as Python code for the generation of random candidates in each round.
Supplementary Data 1
Experimental results of HTS with labels.
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Source Data Fig. 2
Unprocessed picture of gram-scale synthesis.
Source Data Fig. 2
Source data for the SEC trace of Fig. 2c and the 77Se NMR spectrum in Fig. 2e.
Source Data Fig. 3
Source data for the 1H NMR spectrum of Fig. 3a, the gel permeation chromatography trace of Fig. 3b and the circular dichroism spectra of Fig. 3c.
Source Data Fig. 4
Source data for Fig. 4a–c.
Source Data Fig. 5
Source data for Fig. 5c–f.
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Wu, G., Zhou, H., Zhang, J. et al. A high-throughput platform for efficient exploration of functional polypeptide chemical space. Nat. Synth 2, 515–526 (2023). https://doi.org/10.1038/s44160-023-00294-7
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DOI: https://doi.org/10.1038/s44160-023-00294-7
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