1
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Hardy BJ, Curnow P. Computational design of de novo bioenergetic membrane proteins. Biochem Soc Trans 2024:BST20231347. [PMID: 38958574 DOI: 10.1042/bst20231347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 06/11/2024] [Accepted: 06/17/2024] [Indexed: 07/04/2024]
Abstract
The major energy-producing reactions of biochemistry occur at biological membranes. Computational protein design now provides the opportunity to elucidate the underlying principles of these processes and to construct bioenergetic pathways on our own terms. Here, we review recent achievements in this endeavour of 'synthetic bioenergetics', with a particular focus on new enabling tools that facilitate the computational design of biocompatible de novo integral membrane proteins. We use recent examples to showcase some of the key computational approaches in current use and highlight that the overall philosophy of 'surface-swapping' - the replacement of solvent-facing residues with amino acids bearing lipid-soluble hydrophobic sidechains - is a promising avenue in membrane protein design. We conclude by highlighting outstanding design challenges and the emerging role of AI in sequence design and structure ideation.
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Affiliation(s)
| | - Paul Curnow
- School of Biochemistry, University of Bristol, Bristol, U.K
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2
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García-Arnáez I, Romero-Gavilán F, Cerqueira A, Azkargorta M, Elortza F, Suay J, Goñi I, Gurruchaga M. Proteomics as a tool to study the osteoimmunomodulatory role of metallic ions in a sol-gel coating. J Mater Chem B 2023; 11:8194-8205. [PMID: 37552201 DOI: 10.1039/d3tb01204b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
The success of bone implants depends on the osteoimmunomodulatory (OIM) activity of the biomaterials in the interactions with the periimplantary tissues. Many in vitro tests have been conducted to evaluate the osteoimmunology effects of biomaterials. However, results of these tests have often been inconclusive. This study examines the properties of newly developed sol-gel coatings doped with two metal ions associated with bone regeneration, Ca and Zn. The study uses both proteomic methods and traditional in vitro assays. The results demonstrate that proteomics is an effective tool to scrutinize the OIM properties of the materials. Moreover, sol-gel coatings offer excellent base materials to evaluate the effects of metal ions on these properties. The obtained data highlight the highly tunable nature of sol-gel materials; studying the materials with different doping levels supplies valuable information on the interactions between the immune and bone-forming processes.
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Affiliation(s)
- Iñaki García-Arnáez
- Departament of Polymers and Advanced Materials: Physics, Chemistry and Technology, Universidad del País Vasco, Po Manuel de Lardizábal, 3, 20018 San Sebastián, Spain.
| | - Francisco Romero-Gavilán
- Department of Industrial Systems Engineering and Design, Universitat Jaume I, Av. Vicent Sos Baynat s/n, 12071 Castellón de la Plana, Spain
| | - Andreia Cerqueira
- Department of Industrial Systems Engineering and Design, Universitat Jaume I, Av. Vicent Sos Baynat s/n, 12071 Castellón de la Plana, Spain
| | - Mikel Azkargorta
- Proteomics Platform, CIC bioGUNE, Basque Research and Technology Alliance (BRTA), CIBERehd, ProteoRed-ISCIII, Bizkaia Science and Technology Park, 48160 Derio, Spain
| | - Félix Elortza
- Proteomics Platform, CIC bioGUNE, Basque Research and Technology Alliance (BRTA), CIBERehd, ProteoRed-ISCIII, Bizkaia Science and Technology Park, 48160 Derio, Spain
| | - Julio Suay
- Department of Industrial Systems Engineering and Design, Universitat Jaume I, Av. Vicent Sos Baynat s/n, 12071 Castellón de la Plana, Spain
| | - Isabel Goñi
- Departament of Polymers and Advanced Materials: Physics, Chemistry and Technology, Universidad del País Vasco, Po Manuel de Lardizábal, 3, 20018 San Sebastián, Spain.
| | - Mariló Gurruchaga
- Departament of Polymers and Advanced Materials: Physics, Chemistry and Technology, Universidad del País Vasco, Po Manuel de Lardizábal, 3, 20018 San Sebastián, Spain.
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3
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Fujita S, Kawamura I, Kawano R. Cell-Free Expression of De Novo Designed Peptides That Form β-Barrel Nanopores. ACS NANO 2023; 17:3358-3367. [PMID: 36731872 PMCID: PMC9979648 DOI: 10.1021/acsnano.2c07970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 01/03/2023] [Indexed: 06/18/2023]
Abstract
Nanopore sensing has attracted much attention as a rapid, simple, and label-free single-molecule detection technology. To apply nanopore sensing to extensive targets including polypeptides, nanopores are required to have a size and structure suitable for the target. We recently designed a de novo β-barrel peptide nanopore (SVG28) that constructs a stable and monodispersely sized nanopore. To develop the sizes and functionality of peptide nanopores, systematic exploration is required. Here we attempt to use a cell-free synthesis system that can readily express peptides using transcription and translation. Hydrophilic variants of SVG28 were designed and expressed by the PURE system. The peptides form a monodispersely sized nanopore, with a diameter 1.1 or 1.5 nm smaller than that of SVG28. Such cell-free synthesizable peptide nanopores have the potential to enable the systematic custom design of nanopores and comprehensive sequence screening of nanopore-forming peptides.
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Affiliation(s)
- Shoko Fujita
- Department
of Biotechnology and Life Science, Tokyo
University of Agriculture and Technology, Tokyo184-8588, Japan
| | - Izuru Kawamura
- Graduate
School of Engineering Science, Yokohama
National University, Yokohama240-8501, Japan
| | - Ryuji Kawano
- Department
of Biotechnology and Life Science, Tokyo
University of Agriculture and Technology, Tokyo184-8588, Japan
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4
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Sihorwala AZ, Lin AJ, Stachowiak JC, Belardi B. Light-Activated Assembly of Connexon Nanopores in Synthetic Cells. J Am Chem Soc 2023; 145:3561-3568. [PMID: 36724060 PMCID: PMC10188233 DOI: 10.1021/jacs.2c12491] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
During developmental processes and wound healing, activation of living cells occurs with spatiotemporal precision and leads to rapid release of soluble molecular signals, allowing communication and coordination between neighbors. Nonliving systems capable of similar responsive release hold great promise for information transfer in materials and site-specific drug delivery. One nonliving system that offers a tunable platform for programming release is synthetic cells. Encased in a lipid bilayer structure, synthetic cells can be outfitted with molecular conduits that span the bilayer and lead to material exchange. While previous work expressing membrane pore proteins in synthetic cells demonstrated content exchange, user-defined control over release has remained elusive. In mammalian cells, connexon nanopore structures drive content release and have garnered significant interest since they can direct material exchange through intercellular contacts. Here, we focus on connexon nanopores and present activated release of material from synthetic cells in a light-sensitive fashion. To do this, we re-engineer connexon nanopores to assemble after post-translational processing by a protease. By encapsulating proteases in light-sensitive liposomes, we show that assembly of nanopores can be triggered by illumination, resulting in rapid release of molecules encapsulated within synthetic cells. Controlling connexon nanopore activity provides an opportunity for initiating communication with extracellular signals and for transferring molecular agents to the cytoplasm of living cells in a rapid, light-guided manner.
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Affiliation(s)
- Ahmed Z Sihorwala
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Alexander J Lin
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jeanne C Stachowiak
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Brian Belardi
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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5
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Lu H, Cheng Z, Hu Y, Tang LV. What Can De Novo Protein Design Bring to the Treatment of Hematological Disorders? BIOLOGY 2023; 12:biology12020166. [PMID: 36829445 PMCID: PMC9952452 DOI: 10.3390/biology12020166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/22/2023]
Abstract
Protein therapeutics have been widely used to treat hematological disorders. With the advent of de novo protein design, protein therapeutics are not limited to ameliorating natural proteins but also produce novel protein sequences, folds, and functions with shapes and functions customized to bind to the therapeutic targets. De novo protein techniques have been widely used biomedically to design novel diagnostic and therapeutic drugs, novel vaccines, and novel biological materials. In addition, de novo protein design has provided new options for treating hematological disorders. Scientists have designed protein switches called Colocalization-dependent Latching Orthogonal Cage-Key pRoteins (Co-LOCKR) that perform computations on the surface of cells. De novo designed molecules exhibit a better capacity than the currently available tyrosine kinase inhibitors in chronic myeloid leukemia therapy. De novo designed protein neoleukin-2/15 enhances chimeric antigen receptor T-cell activity. This new technique has great biomedical potential, especially in exploring new treatment methods for hematological disorders. This review discusses the development of de novo protein design and its biological applications, with emphasis on the treatment of hematological disorders.
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6
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Zhou C, Lu P. De novo
design of membrane transport proteins. Proteins 2022; 90:1800-1806. [DOI: 10.1002/prot.26336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/07/2022] [Accepted: 03/12/2022] [Indexed: 12/22/2022]
Affiliation(s)
- Chen Zhou
- Westlake Laboratory of Life Sciences and Biomedicine Hangzhou Zhejiang China
- Key Laboratory of Structural Biology of Zhejiang Province School of Life Sciences, Westlake University Hangzhou Zhejiang China
- Institute of Biology Westlake Institute for Advanced Study Hangzhou Zhejiang China
| | - Peilong Lu
- Westlake Laboratory of Life Sciences and Biomedicine Hangzhou Zhejiang China
- Key Laboratory of Structural Biology of Zhejiang Province School of Life Sciences, Westlake University Hangzhou Zhejiang China
- Institute of Biology Westlake Institute for Advanced Study Hangzhou Zhejiang China
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7
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8
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Taylor A, Warner M, Mendoza C, Memmott C, LeCheminant T, Bailey S, Christensen C, Keller J, Suli A, Mizrachi D. Chimeric Claudins: A New Tool to Study Tight Junction Structure and Function. Int J Mol Sci 2021; 22:ijms22094947. [PMID: 34066630 PMCID: PMC8124314 DOI: 10.3390/ijms22094947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/02/2021] [Accepted: 05/04/2021] [Indexed: 12/11/2022] Open
Abstract
The tight junction (TJ) is a structure composed of multiple proteins, both cytosolic and membranal, responsible for cell–cell adhesion in polarized endothelium and epithelium. The TJ is intimately connected to the cytoskeleton and plays a role in development and homeostasis. Among the TJ’s membrane proteins, claudins (CLDNs) are key to establishing blood–tissue barriers that protect organismal physiology. Recently, several crystal structures have been reported for detergent extracted recombinant CLDNs. These structural advances lack direct evidence to support quaternary structure of CLDNs. In this article, we have employed protein-engineering principles to create detergent-independent chimeric CLDNs, a combination of a 4-helix bundle soluble monomeric protein (PDB ID: 2jua) and the apical—50% of human CLDN1, the extracellular domain that is responsible for cell–cell adhesion. Maltose-binding protein-fused chimeric CLDNs (MBP-CCs) used in this study are soluble proteins that retain structural and functional aspects of native CLDNs. Here, we report the biophysical characterization of the structure and function of MBP-CCs. MBP-fused epithelial cadherin (MBP-eCAD) is used as a control and point of comparison of a well-characterized cell-adhesion molecule. Our synthetic strategy may benefit other families of 4-α-helix membrane proteins, including tetraspanins, connexins, pannexins, innexins, and more.
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9
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Vorobieva AA, White P, Liang B, Horne JE, Bera AK, Chow CM, Gerben S, Marx S, Kang A, Stiving AQ, Harvey SR, Marx DC, Khan GN, Fleming KG, Wysocki VH, Brockwell DJ, Tamm LK, Radford SE, Baker D. De novo design of transmembrane β barrels. Science 2021; 371:eabc8182. [PMID: 33602829 PMCID: PMC8064278 DOI: 10.1126/science.abc8182] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 12/07/2020] [Indexed: 12/12/2022]
Abstract
Transmembrane β-barrel proteins (TMBs) are of great interest for single-molecule analytical technologies because they can spontaneously fold and insert into membranes and form stable pores, but the range of pore properties that can be achieved by repurposing natural TMBs is limited. We leverage the power of de novo computational design coupled with a "hypothesis, design, and test" approach to determine TMB design principles, notably, the importance of negative design to slow β-sheet assembly. We design new eight-stranded TMBs, with no homology to known TMBs, that insert and fold reversibly into synthetic lipid membranes and have nuclear magnetic resonance and x-ray crystal structures very similar to the computational models. These advances should enable the custom design of pores for a wide range of applications.
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Affiliation(s)
- Anastassia A Vorobieva
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA
| | - Paul White
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, USA
| | - Binyong Liang
- Department of Molecular Physiology and Biological Physics and Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22903, USA
| | - Jim E Horne
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, USA
| | - Asim K Bera
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
- Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Cameron M Chow
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
- Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Stacey Gerben
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Sinduja Marx
- Department of Molecular Engineering and Sciences, University of Washington, Seattle, WA 98195, USA
| | - Alex Kang
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
- Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Alyssa Q Stiving
- Department of Chemistry and Biochemistry, Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Sophie R Harvey
- Department of Chemistry and Biochemistry, Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Dagan C Marx
- TC Jenkins Department of Biophysics Johns Hopkins University, Baltimore, MD 21218, USA
| | - G Nasir Khan
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, USA
| | - Karen G Fleming
- TC Jenkins Department of Biophysics Johns Hopkins University, Baltimore, MD 21218, USA
| | - Vicki H Wysocki
- Department of Chemistry and Biochemistry, Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA
| | - David J Brockwell
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, USA
| | - Lukas K Tamm
- Department of Molecular Physiology and Biological Physics and Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, VA 22903, USA
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, USA
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.
- Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA
- Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
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10
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11
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Abstract
Protein pores play key roles in fundamental biological processes1 and biotechnological applications such as DNA nanopore sequencing2–4, and hence the design of pore-containing proteins is of considerable scientific and biotechnological interest. Synthetic amphiphilic peptides have been found to form ion channels5,6, and there have been recent advances in de novo membrane protein design7,8 and in redesigning naturally occurring channel-containing proteins9,10. However, the de novo design of stable, well-defined transmembrane protein pores capable of conducting ions selectively or large enough to allow passage of small-molecule fluorophores remains an outstanding challenge11,12. Here, we report the computational design of protein pores formed by two concentric rings of ɑ-helices that are stable and mono-disperse in both water-soluble and transmembrane forms. Crystal structures of the water-soluble forms of a 12 helical and a 16 helical pore are close to the computational design models. Patch-clamp electrophysiology experiments show that the transmembrane form of the 12-helix pore expressed in insect cells allows passage of ions across the membrane with high selectivity for potassium over sodium, which is blocked by specific chemical modification at the pore entrance. The transmembrane form of the 16-helix pore, but not the 12-helix pore, allows passage of biotinylated Alexa Fluor 488 when incorporated into liposomes using in vitro protein synthesis. A cryo-EM structure of the 16-helix transmembrane pore closely matches the design model. The ability to produce structurally and functionally well-defined transmembrane pores opens the door to the creation of designer pores for a wide variety of applications.
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12
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Wei KY, Moschidi D, Bick MJ, Nerli S, McShan AC, Carter LP, Huang PS, Fletcher DA, Sgourakis NG, Boyken SE, Baker D. Computational design of closely related proteins that adopt two well-defined but structurally divergent folds. Proc Natl Acad Sci U S A 2020; 117:7208-7215. [PMID: 32188784 PMCID: PMC7132107 DOI: 10.1073/pnas.1914808117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The plasticity of naturally occurring protein structures, which can change shape considerably in response to changes in environmental conditions, is critical to biological function. While computational methods have been used for de novo design of proteins that fold to a single state with a deep free-energy minimum [P.-S. Huang, S. E. Boyken, D. Baker, Nature 537, 320-327 (2016)], and to reengineer natural proteins to alter their dynamics [J. A. Davey, A. M. Damry, N. K. Goto, R. A. Chica, Nat. Chem. Biol. 13, 1280-1285 (2017)] or fold [P. A. Alexander, Y. He, Y. Chen, J. Orban, P. N. Bryan, Proc. Natl. Acad. Sci. U.S.A. 106, 21149-21154 (2009)], the de novo design of closely related sequences which adopt well-defined but structurally divergent structures remains an outstanding challenge. We designed closely related sequences (over 94% identity) that can adopt two very different homotrimeric helical bundle conformations-one short (∼66 Å height) and the other long (∼100 Å height)-reminiscent of the conformational transition of viral fusion proteins. Crystallographic and NMR spectroscopic characterization shows that both the short- and long-state sequences fold as designed. We sought to design bistable sequences for which both states are accessible, and obtained a single designed protein sequence that populates either the short state or the long state depending on the measurement conditions. The design of sequences which are poised to adopt two very different conformations sets the stage for creating large-scale conformational switches between structurally divergent forms.
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Affiliation(s)
- Kathy Y Wei
- Department of Biochemistry, University of Washington, Seattle, WA 98195
- Institute for Protein Design, University of Washington, Seattle, WA 98195
- Department of Bioengineering, University of California, Berkeley, CA 94720
| | - Danai Moschidi
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064
| | - Matthew J Bick
- Department of Biochemistry, University of Washington, Seattle, WA 98195
- Institute for Protein Design, University of Washington, Seattle, WA 98195
| | - Santrupti Nerli
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064
- Department of Computer Science, University of California, Santa Cruz, CA 95064
| | - Andrew C McShan
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064
| | - Lauren P Carter
- Institute for Protein Design, University of Washington, Seattle, WA 98195
| | - Po-Ssu Huang
- Department of Bioengineering, Stanford University, Stanford, CA 94305
| | - Daniel A Fletcher
- Department of Bioengineering, University of California, Berkeley, CA 94720
- Joint UC Berkeley-UC San Francisco Graduate Group in Bioengineering, Berkeley, CA 94720
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Chan Zuckerberg Biohub, San Francisco, CA 94158
| | - Nikolaos G Sgourakis
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064
| | - Scott E Boyken
- Department of Biochemistry, University of Washington, Seattle, WA 98195;
- Institute for Protein Design, University of Washington, Seattle, WA 98195
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA 98195;
- Institute for Protein Design, University of Washington, Seattle, WA 98195
- Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195
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13
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Eguchi RR, Huang PS. Multi-scale structural analysis of proteins by deep semantic segmentation. Bioinformatics 2020; 36:1740-1749. [PMID: 31424530 PMCID: PMC7075530 DOI: 10.1093/bioinformatics/btz650] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 07/29/2019] [Accepted: 08/18/2019] [Indexed: 11/12/2022] Open
Abstract
MOTIVATION Recent advances in computational methods have facilitated large-scale sampling of protein structures, leading to breakthroughs in protein structural prediction and enabling de novo protein design. Establishing methods to identify candidate structures that can lead to native folds or designable structures remains a challenge, since few existing metrics capture high-level structural features such as architectures, folds and conformity to conserved structural motifs. Convolutional Neural Networks (CNNs) have been successfully used in semantic segmentation-a subfield of image classification in which a class label is predicted for every pixel. Here, we apply semantic segmentation to protein structures as a novel strategy for fold identification and structure quality assessment. RESULTS We train a CNN that assigns each residue in a multi-domain protein to one of 38 architecture classes designated by the CATH database. Our model achieves a high per-residue accuracy of 90.8% on the test set (95.0% average per-class accuracy; 87.8% average per-structure accuracy). We demonstrate that individual class probabilities can be used as a metric that indicates the degree to which a randomly generated structure assumes a specific fold, as well as a metric that highlights non-conformative regions of a protein belonging to a known class. These capabilities yield a powerful tool for guiding structural sampling for both structural prediction and design. AVAILABILITY AND IMPLEMENTATION The trained classifier network, parser network, and entropy calculation scripts are available for download at https://git.io/fp6bd, with detailed usage instructions provided at the download page. A step-by-step tutorial for setup is provided at https://goo.gl/e8GB2S. All Rosetta commands, RosettaRemodel blueprints, and predictions for all datasets used in the study are available in the Supplementary Information. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Raphael R Eguchi
- Department of Biochemistry, School of Medicine, Stanford University, Shriram Center for Bioengineering and Chemical Engineering, 443 via Ortega, Room 036, Stanford, CA 94305, USA
| | - Po-Ssu Huang
- Department of Bioengineering, Schools of Engineering and Medicine, Stanford University Shriram Center for Bioengineering and Chemical Engineering, 443 via Ortega, Room 036, Stanford, CA 94305, USA
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14
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Abstract
Proteins are molecular machines whose function depends on their ability to achieve complex folds with precisely defined structural and dynamic properties. The rational design of proteins from first-principles, or de novo, was once considered to be impossible, but today proteins with a variety of folds and functions have been realized. We review the evolution of the field from its earliest days, placing particular emphasis on how this endeavor has illuminated our understanding of the principles underlying the folding and function of natural proteins, and is informing the design of macromolecules with unprecedented structures and properties. An initial set of milestones in de novo protein design focused on the construction of sequences that folded in water and membranes to adopt folded conformations. The first proteins were designed from first-principles using very simple physical models. As computers became more powerful, the use of the rotamer approximation allowed one to discover amino acid sequences that stabilize the desired fold. As the crystallographic database of protein structures expanded in subsequent years, it became possible to construct proteins by assembling short backbone fragments that frequently recur in Nature. The second set of milestones in de novo design involves the discovery of complex functions. Proteins have been designed to bind a variety of metals, porphyrins, and other cofactors. The design of proteins that catalyze hydrolysis and oxygen-dependent reactions has progressed significantly. However, de novo design of catalysts for energetically demanding reactions, or even proteins that bind with high affinity and specificity to highly functionalized complex polar molecules remains an importnant challenge that is now being achieved. Finally, the protein design contributed significantly to our understanding of membrane protein folding and transport of ions across membranes. The area of membrane protein design, or more generally of biomimetic polymers that function in mixed or non-aqueous environments, is now becoming increasingly possible.
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15
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Grayson KJ, Anderson JLR. Designed for life: biocompatible de novo designed proteins and components. J R Soc Interface 2019; 15:rsif.2018.0472. [PMID: 30158186 PMCID: PMC6127164 DOI: 10.1098/rsif.2018.0472] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 08/01/2018] [Indexed: 12/30/2022] Open
Abstract
A principal goal of synthetic biology is the de novo design or redesign of biomolecular components. In addition to revealing fundamentally important information regarding natural biomolecular engineering and biochemistry, functional building blocks will ultimately be provided for applications including the manufacture of valuable products and therapeutics. To fully realize this ambitious goal, the designed components must be biocompatible, working in concert with natural biochemical processes and pathways, while not adversely affecting cellular function. For example, de novo protein design has provided us with a wide repertoire of structures and functions, including those that can be assembled and function in vivo. Here we discuss such biocompatible designs, as well as others that have the potential to become biocompatible, including non-protein molecules, and routes to achieving full biological integration.
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Affiliation(s)
- Katie J Grayson
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, Bristol BS8 1TD, UK
| | - J L Ross Anderson
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, Bristol BS8 1TD, UK .,BrisSynBio Synthetic Biology Research Centre, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
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16
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Weinstein JY, Elazar A, Fleishman SJ. A lipophilicity-based energy function for membrane-protein modelling and design. PLoS Comput Biol 2019; 15:e1007318. [PMID: 31461441 PMCID: PMC6736313 DOI: 10.1371/journal.pcbi.1007318] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 09/10/2019] [Accepted: 08/01/2019] [Indexed: 01/14/2023] Open
Abstract
Membrane-protein design is an exciting and increasingly successful research area which has led to landmarks including the design of stable and accurate membrane-integral proteins based on coiled-coil motifs. Design of topologically more complex proteins, such as most receptors, channels, and transporters, however, demands an energy function that balances contributions from intra-protein contacts and protein-membrane interactions. Recent advances in water-soluble all-atom energy functions have increased the accuracy in structure-prediction benchmarks. The plasma membrane, however, imposes different physical constraints on protein solvation. To understand these constraints, we recently developed a high-throughput experimental screen, called dsTβL, and inferred apparent insertion energies for each amino acid at dozens of positions across the bacterial plasma membrane. Here, we express these profiles as lipophilicity energy terms in Rosetta and demonstrate that the new energy function outperforms previous ones in modelling and design benchmarks. Rosetta ab initio simulations starting from an extended chain recapitulate two-thirds of the experimentally determined structures of membrane-spanning homo-oligomers with <2.5Å root-mean-square deviation within the top-predicted five models (available online: http://tmhop.weizmann.ac.il). Furthermore, in two sequence-design benchmarks, the energy function improves discrimination of stabilizing point mutations and recapitulates natural membrane-protein sequences of known structure, thereby recommending this new energy function for membrane-protein modelling and design.
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Affiliation(s)
| | - Assaf Elazar
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Sarel Jacob Fleishman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
- * E-mail:
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Gilbert RJC, Bayley H, Anderluh G. Membrane pores: from structure and assembly, to medicine and technology. Philos Trans R Soc Lond B Biol Sci 2018. [PMID: 28630148 DOI: 10.1098/rstb.2016.0208] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Robert J C Gilbert
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Hagan Bayley
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, UK
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
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