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Chu AE, Lu T, Huang PS. Sparks of function by de novo protein design. Nat Biotechnol 2024; 42:203-215. [PMID: 38361073 DOI: 10.1038/s41587-024-02133-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Accepted: 01/09/2024] [Indexed: 02/17/2024]
Abstract
Information in proteins flows from sequence to structure to function, with each step causally driven by the preceding one. Protein design is founded on inverting this process: specify a desired function, design a structure executing this function, and find a sequence that folds into this structure. This 'central dogma' underlies nearly all de novo protein-design efforts. Our ability to accomplish these tasks depends on our understanding of protein folding and function and our ability to capture this understanding in computational methods. In recent years, deep learning-derived approaches for efficient and accurate structure modeling and enrichment of successful designs have enabled progression beyond the design of protein structures and towards the design of functional proteins. We examine these advances in the broader context of classical de novo protein design and consider implications for future challenges to come, including fundamental capabilities such as sequence and structure co-design and conformational control considering flexibility, and functional objectives such as antibody and enzyme design.
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Affiliation(s)
- Alexander E Chu
- Biophysics Program, Stanford University, Palo Alto, CA, USA
- Department of Bioengineering, Stanford University, Palo Alto, CA, USA
- Google DeepMind, London, UK
| | - Tianyu Lu
- Department of Bioengineering, Stanford University, Palo Alto, CA, USA
| | - Po-Ssu Huang
- Biophysics Program, Stanford University, Palo Alto, CA, USA.
- Department of Bioengineering, Stanford University, Palo Alto, CA, USA.
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2
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Komarov IV, Bugrov VA, Cherednychenko A, Grygorenko OO. Insights into Modeling Approaches in Chemistry: Assessing Ligand-Protein Binding Thermodynamics Based on Rigid-Flexible Model Molecules. CHEM REC 2024; 24:e202300276. [PMID: 37847887 DOI: 10.1002/tcr.202300276] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/29/2023] [Indexed: 10/19/2023]
Abstract
In the field of chemistry, model compounds find extensive use for investigating complex objects. One prime example of such object is the protein-ligand supramolecular interaction. Prediction the enthalpic and entropic contribution to the free energy associated with this process, as well as the structural and dynamic characteristics of protein-ligand complexes poses considerable challenges. This review exemplifies modeling approaches used to study protein-ligand binding (PLB) thermodynamics by employing pairs of conformationally constrained/flexible model molecules. Strategically designing the model molecules can reduce the number of variables that influence thermodynamic parameters. This enables scientists to gain deeper insights into the enthalpy and entropy of PLB, which is relevant for medicinal chemistry and drug design. The model studies reviewed here demonstrate that rigidifying ligands may induce compensating changes in the enthalpy and entropy of binding. Some "rules of thumb" have started to emerge on how to minimize entropy-enthalpy compensation and design efficient rigidified or flexible ligands.
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Affiliation(s)
- Igor V Komarov
- Taras Shevchenko National University of Kyiv, Volodymyrska Street 60, Kyiv, 01601, Ukraine
- Enamine Ltd., Winston Churchill Street 78, Kyiv, 02094, Ukraine
| | - Volodymyr A Bugrov
- Taras Shevchenko National University of Kyiv, Volodymyrska Street 60, Kyiv, 01601, Ukraine
| | - Anton Cherednychenko
- Taras Shevchenko National University of Kyiv, Volodymyrska Street 60, Kyiv, 01601, Ukraine
- Enamine Ltd., Winston Churchill Street 78, Kyiv, 02094, Ukraine
| | - Oleksandr O Grygorenko
- Taras Shevchenko National University of Kyiv, Volodymyrska Street 60, Kyiv, 01601, Ukraine
- Enamine Ltd., Winston Churchill Street 78, Kyiv, 02094, Ukraine
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3
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Fatima S, Boggs DG, Ali N, Thompson PJ, Thielges MC, Bridwell-Rabb J, Olshansky L. Engineering a Conformationally Switchable Artificial Metalloprotein. J Am Chem Soc 2022; 144:21606-21616. [DOI: 10.1021/jacs.2c08885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Saman Fatima
- Department of Chemistry, University of Illinois Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois61801, United States
| | - David G. Boggs
- Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan48109, United States
| | - Noor Ali
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana47405, United States
| | - Peter J. Thompson
- Center for Biophysics and Quantitative Biology, University of Illinois Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois61801, United States
| | - Megan C. Thielges
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana47405, United States
| | - Jennifer Bridwell-Rabb
- Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan48109, United States
| | - Lisa Olshansky
- Department of Chemistry, University of Illinois Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois61801, United States
- Center for Biophysics and Quantitative Biology, University of Illinois Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois61801, United States
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4
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Miniproteins in medicinal chemistry. Bioorg Med Chem Lett 2022; 71:128806. [PMID: 35660515 DOI: 10.1016/j.bmcl.2022.128806] [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: 01/31/2022] [Revised: 05/11/2022] [Accepted: 05/16/2022] [Indexed: 11/20/2022]
Abstract
Miniproteins exhibit great potential as scaffolds for drug candidates because of their well-defined structure and good synthetic availability. Because of recently described methodologies for their de novo design, the field of miniproteins is emerging and can provide molecules that effectively bind to problematic targets, i.e., those that have been previously considered to be undruggable. This review describes methodologies for the development of miniprotein scaffolds and for the construction of biologically active miniproteins.
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5
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Kerns S, Biswas A, Minnetian NM, Borovik AS. Artificial Metalloproteins: At the Interface between Biology and Chemistry. JACS AU 2022; 2:1252-1265. [PMID: 35783165 PMCID: PMC9241007 DOI: 10.1021/jacsau.2c00102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/13/2022] [Accepted: 04/15/2022] [Indexed: 05/22/2023]
Abstract
Artificial metalloproteins (ArMs) have recently gained significant interest due to their potential to address issues in a broad scope of applications, including biocatalysis, biotechnology, protein assembly, and model chemistry. ArMs are assembled by the incorporation of a non-native metallocofactor into a protein scaffold. This can be achieved by a number of methods that apply tools of chemical biology, computational de novo design, and synthetic chemistry. In this Perspective, we highlight select systems in the hope of demonstrating the breadth of ArM design strategies and applications and emphasize how these systems address problems that are otherwise difficult to do so with strictly biochemical or synthetic approaches.
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6
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Guo R, Sinha NJ, Misra R, Tang Y, Langenstein M, Kim K, Fagan JA, Kloxin CJ, Jensen G, Pochan DJ, Saven JG. Computational Design of Homotetrameric Peptide Bundle Variants Spanning a Wide Range of Charge States. Biomacromolecules 2022; 23:1652-1661. [PMID: 35312288 DOI: 10.1021/acs.biomac.1c01539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
With the ability to design their sequences and structures, peptides can be engineered to realize a wide variety of functionalities and structures. Herein, computational design was used to identify a set of 17 peptides having a wide range of putative charge states but the same tetrameric coiled-coil bundle structure. Calculations were performed to identify suitable locations for ionizable residues (D, E, K, and R) at the bundle's exterior sites, while interior hydrophobic interactions were retained. The designed bundle structures spanned putative charge states of -32 to +32 in units of electron charge. The peptides were experimentally investigated using spectroscopic and scattering techniques. Thermal stabilities of the bundles were investigated using circular dichroism. Molecular dynamics simulations assessed structural fluctuations within the bundles. The cylindrical peptide bundles, 4 nm long by 2 nm in diameter, were covalently linked to form rigid, micron-scale polymers and characterized using transmission electron microscopy. The designed suite of sequences provides a set of readily realized nanometer-scale structures of tunable charge that can also be polymerized to yield rigid-rod polyelectrolytes.
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Affiliation(s)
- Rui Guo
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Nairiti J Sinha
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States.,NIST Center for Neutron Research (NCNR), National Institute of Standards & Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Rajkumar Misra
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Yao Tang
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Matthew Langenstein
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Kyunghee Kim
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Jeffrey A Fagan
- Materials Science and Engineering Division, National Institute of Standards & Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Christopher J Kloxin
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States.,Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Grethe Jensen
- NIST Center for Neutron Research (NCNR), National Institute of Standards & Technology (NIST), Gaithersburg, Maryland 20899, United States.,Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Darrin J Pochan
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Jeffery G Saven
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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7
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Yu Y, Wang R, Teo RD. Machine Learning Approaches for Metalloproteins. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27041277. [PMID: 35209064 PMCID: PMC8878495 DOI: 10.3390/molecules27041277] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 01/10/2023]
Abstract
Metalloproteins are a family of proteins characterized by metal ion binding, whereby the presence of these ions confers key catalytic and ligand-binding properties. Due to their ubiquity among biological systems, researchers have made immense efforts to predict the structural and functional roles of metalloproteins. Ultimately, having a comprehensive understanding of metalloproteins will lead to tangible applications, such as designing potent inhibitors in drug discovery. Recently, there has been an acceleration in the number of studies applying machine learning to predict metalloprotein properties, primarily driven by the advent of more sophisticated machine learning algorithms. This review covers how machine learning tools have consolidated and expanded our comprehension of various aspects of metalloproteins (structure, function, stability, ligand-binding interactions, and inhibitors). Future avenues of exploration are also discussed.
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Affiliation(s)
- Yue Yu
- Division of Natural and Applied Sciences, Duke Kunshan University, Kunshan, Jiangsu 215316, China;
- Department of Physics, Duke University, Durham, NC 27708, USA
| | - Ruobing Wang
- Department of Chemistry, Duke University, Durham, NC 27708, USA;
| | - Ruijie D. Teo
- Department of Chemistry, Duke University, Durham, NC 27708, USA;
- UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Correspondence:
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8
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Mutant libraries reveal negative design shielding proteins from supramolecular self-assembly and relocalization in cells. Proc Natl Acad Sci U S A 2022; 119:2101117119. [PMID: 35078932 PMCID: PMC8812688 DOI: 10.1073/pnas.2101117119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2021] [Indexed: 01/07/2023] Open
Abstract
Genetic mutations fuel organismal evolution but can also cause disease. As proteins are the cell’s workhorses, the ways in which mutations can disrupt their structure, stability, function, and interactions have been studied extensively. However, proteins evolve and function in a cellular context, and our ability to relate changes in protein sequence to cell-level phenotypes remains limited. In particular, the molecular mechanism underlying most disease-associated mutations is unknown. Here, we show that mutations changing a protein’s surface chemistry can dramatically impact its supramolecular self-assembly and localization in the cell. These results highlight the complex nature of genotype–phenotype relationships with a simple system. Understanding the molecular consequences of mutations in proteins is essential to map genotypes to phenotypes and interpret the increasing wealth of genomic data. While mutations are known to disrupt protein structure and function, their potential to create new structures and localization phenotypes has not yet been mapped to a sequence space. To map this relationship, we employed two homo-oligomeric protein complexes in which the internal symmetry exacerbates the impact of mutations. We mutagenized three surface residues of each complex and monitored the mutations’ effect on localization and assembly phenotypes in yeast cells. While surface mutations are classically viewed as benign, our analysis of several hundred mutants revealed they often trigger three main phenotypes in these proteins: nuclear localization, the formation of puncta, and fibers. Strikingly, more than 50% of random mutants induced one of these phenotypes in both complexes. Analyzing the mutant’s sequences showed that surface stickiness and net charge are two key physicochemical properties associated with these changes. In one complex, more than 60% of mutants self-assembled into fibers. Such a high frequency is explained by negative design: charged residues shield the complex from self-interacting with copies of itself, and the sole removal of the charges induces its supramolecular self-assembly. A subsequent analysis of several other complexes targeted with alanine mutations suggested that such negative design is common. These results highlight that minimal perturbations in protein surfaces’ physicochemical properties can frequently drive assembly and localization changes in a cellular context.
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10
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Slope LN, Daubney OJ, Campbell H, White SA, Peacock AFA. Location-Dependent Lanthanide Selectivity Engineered into Structurally Characterized Designed Coiled Coils. Angew Chem Int Ed Engl 2021; 60:24473-24477. [PMID: 34495573 PMCID: PMC8597134 DOI: 10.1002/anie.202110500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Indexed: 11/08/2022]
Abstract
Herein we report unprecedented location-dependent, size-selective binding to designed lanthanide (Ln3+ ) sites within miniature protein coiled coil scaffolds. Not only do these engineered sites display unusual Ln3+ selectivity for moderately large Ln3+ ions (Nd to Tb), for the first time we demonstrate that selectivity can be location-dependent and can be programmed into the sequence. A 1 nm linear translation of the binding site towards the N-terminus can convert a selective site into a highly promiscuous one. An X-ray crystal structure, the first of a lanthanide binding site within a coiled coil to be reported, coupled with CD studies, reveal the existence of an optimal radius that likely stems from the structural constraints of the coiled coil scaffold. To the best of our knowledge this is the first report of location-dependent metal selectivity within a coiled coil scaffold, as well as the first report of location-dependent Ln3+ selectivity within a protein.
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Affiliation(s)
- Louise N. Slope
- School of ChemistryUniversity of BirminghamEdgbastonB15 2TTUK
| | | | - Hannah Campbell
- School of ChemistryUniversity of BirminghamEdgbastonB15 2TTUK
| | - Scott A. White
- School of BiosciencesUniversity of BirminghamEdgbastonB15 2TTUK
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11
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Slope LN, Daubney OJ, Campbell H, White SA, Peacock AFA. Location‐Dependent Lanthanide Selectivity Engineered into Structurally Characterized Designed Coiled Coils. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202110500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Louise N. Slope
- School of Chemistry University of Birmingham Edgbaston B15 2TT UK
| | | | - Hannah Campbell
- School of Chemistry University of Birmingham Edgbaston B15 2TT UK
| | - Scott A. White
- School of Biosciences University of Birmingham Edgbaston B15 2TT UK
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12
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Rudnev VR, Kulikova LI, Nikolsky KS, Malsagova KA, Kopylov AT, Kaysheva AL. Current Approaches in Supersecondary Structures Investigation. Int J Mol Sci 2021; 22:11879. [PMID: 34769310 PMCID: PMC8584461 DOI: 10.3390/ijms222111879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/27/2021] [Accepted: 10/29/2021] [Indexed: 11/16/2022] Open
Abstract
Proteins expressed during the cell cycle determine cell function, topology, and responses to environmental influences. The development and improvement of experimental methods in the field of structural biology provide valuable information about the structure and functions of individual proteins. This work is devoted to the study of supersecondary structures of proteins and determination of their structural motifs, description of experimental methods for their detection, databases, and repositories for storage, as well as methods of molecular dynamics research. The interest in the study of supersecondary structures in proteins is due to their autonomous stability outside the protein globule, which makes it possible to study folding processes, conformational changes in protein isoforms, and aberrant proteins with high productivity.
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Affiliation(s)
- Vladimir R. Rudnev
- Biobanking Group, Branch of Institute of Biomedical Chemistry “Scientific and Education Center”, 109028 Moscow, Russia; (V.R.R.); (L.I.K.); (K.S.N.); (A.T.K.); (A.L.K.)
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Russia
| | - Liudmila I. Kulikova
- Biobanking Group, Branch of Institute of Biomedical Chemistry “Scientific and Education Center”, 109028 Moscow, Russia; (V.R.R.); (L.I.K.); (K.S.N.); (A.T.K.); (A.L.K.)
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Russia
- Institute of Mathematical Problems of Biology RAS—The Branch of Keldysh Institute of Applied Mathematics of Russian Academy of Sciences, 142290 Pushchino, Russia
| | - Kirill S. Nikolsky
- Biobanking Group, Branch of Institute of Biomedical Chemistry “Scientific and Education Center”, 109028 Moscow, Russia; (V.R.R.); (L.I.K.); (K.S.N.); (A.T.K.); (A.L.K.)
| | - Kristina A. Malsagova
- Biobanking Group, Branch of Institute of Biomedical Chemistry “Scientific and Education Center”, 109028 Moscow, Russia; (V.R.R.); (L.I.K.); (K.S.N.); (A.T.K.); (A.L.K.)
| | - Arthur T. Kopylov
- Biobanking Group, Branch of Institute of Biomedical Chemistry “Scientific and Education Center”, 109028 Moscow, Russia; (V.R.R.); (L.I.K.); (K.S.N.); (A.T.K.); (A.L.K.)
| | - Anna L. Kaysheva
- Biobanking Group, Branch of Institute of Biomedical Chemistry “Scientific and Education Center”, 109028 Moscow, Russia; (V.R.R.); (L.I.K.); (K.S.N.); (A.T.K.); (A.L.K.)
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Woolfson DN. A Brief History of De Novo Protein Design: Minimal, Rational, and Computational. J Mol Biol 2021; 433:167160. [PMID: 34298061 DOI: 10.1016/j.jmb.2021.167160] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/07/2021] [Accepted: 07/12/2021] [Indexed: 12/26/2022]
Abstract
Protein design has come of age, but how will it mature? In the 1980s and the 1990s, the primary motivation for de novo protein design was to test our understanding of the informational aspect of the protein-folding problem; i.e., how does protein sequence determine protein structure and function? This necessitated minimal and rational design approaches whereby the placement of each residue in a design was reasoned using chemical principles and/or biochemical knowledge. At that time, though with some notable exceptions, the use of computers to aid design was not widespread. Over the past two decades, the tables have turned and computational protein design is firmly established. Here, I illustrate this progress through a timeline of de novo protein structures that have been solved to atomic resolution and deposited in the Protein Data Bank. From this, it is clear that the impact of rational and computational design has been considerable: More-complex and more-sophisticated designs are being targeted with many being resolved to atomic resolution. Furthermore, our ability to generate and manipulate synthetic proteins has advanced to a point where they are providing realistic alternatives to natural protein functions for applications both in vitro and in cells. Also, and increasingly, computational protein design is becoming accessible to non-specialists. This all begs the questions: Is there still a place for minimal and rational design approaches? And, what challenges lie ahead for the burgeoning field of de novo protein design as a whole?
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Affiliation(s)
- Derek N Woolfson
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK; School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK; Bristol BioDesign Institute, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK.
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14
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Kim K, Kloxin CJ, Saven JG, Pochan DJ. Nanofibers Produced by Electrospinning of Ultrarigid Polymer Rods Made from Designed Peptide Bundlemers. ACS APPLIED MATERIALS & INTERFACES 2021; 13:26339-26351. [PMID: 34029045 DOI: 10.1021/acsami.1c04027] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Mimicking the hierarchical assembly of natural fiber materials is an important design challenge in the manufacturing of nanostructured materials with biomolecules such as peptides. Here, we produce nanofibers with control of structure over multiple length scales, ranging from peptide molecule assembly into supramolecular building blocks called "bundlemers," to rigid-rod formation through a covalent connection of bundlemer building blocks, and, ultimately, to uniaxially oriented fibers made with the rigid-rod polymers. The peptides are designed to physically assemble into coiled-coil bundles, or bundlemers, and to covalently interact in an end-to-end fashion to produce the rigid-rod polymer. The resultant rodlike polymer exhibits a rigid, cylindrical nanostructure confirmed by transmission electron microscopy (TEM) and, correspondingly, exhibits shear-thinning behavior at low shear rates observed in many nanoscopic rod systems. The rigid-rod chains are further organized into final fiber materials via electrospinning processing, all the while preserving their unique rodlike structural characteristics. Morphological and structural investigations of the nanofibers through scanning electron microscopy, transmission electron microscopy, and X-ray scattering, as well as molecular characterization via Fourier transform infrared (FTIR) and Raman spectroscopy, show that continuous nanofibers are composed of oriented rigid-rod chains constituted by α-helical peptides within bundle building blocks. Mechanical properties of electrospun fibers are also presented. The ability to produce nanofibers from the oriented rigid-rod polymer reveals bundlemer chains as a viable tool for the development of new fiber materials with targeted structure and properties.
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Affiliation(s)
- Kyunghee Kim
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Christopher J Kloxin
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Jeffery G Saven
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Darrin J Pochan
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
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15
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Hamley IW. Biocatalysts Based on Peptide and Peptide Conjugate Nanostructures. Biomacromolecules 2021; 22:1835-1855. [PMID: 33843196 PMCID: PMC8154259 DOI: 10.1021/acs.biomac.1c00240] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/31/2021] [Indexed: 12/15/2022]
Abstract
Peptides and their conjugates (to lipids, bulky N-terminals, or other groups) can self-assemble into nanostructures such as fibrils, nanotubes, coiled coil bundles, and micelles, and these can be used as platforms to present functional residues in order to catalyze a diversity of reactions. Peptide structures can be used to template catalytic sites inspired by those present in natural enzymes as well as simpler constructs using individual catalytic amino acids, especially proline and histidine. The literature on the use of peptide (and peptide conjugate) α-helical and β-sheet structures as well as turn or disordered peptides in the biocatalysis of a range of organic reactions including hydrolysis and a variety of coupling reactions (e.g., aldol reactions) is reviewed. The simpler design rules for peptide structures compared to those of folded proteins permit ready ab initio design (minimalist approach) of effective catalytic structures that mimic the binding pockets of natural enzymes or which simply present catalytic motifs at high density on nanostructure scaffolds. Research on these topics is summarized, along with a discussion of metal nanoparticle catalysts templated by peptide nanostructures, especially fibrils. Research showing the high activities of different classes of peptides in catalyzing many reactions is highlighted. Advances in peptide design and synthesis methods mean they hold great potential for future developments of effective bioinspired and biocompatible catalysts.
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Affiliation(s)
- Ian W. Hamley
- Department of Chemistry, University of Reading, RG6 6AD Reading, United Kingdom
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Marzolf DR, Seffernick JT, Lindert S. Protein Structure Prediction from NMR Hydrogen-Deuterium Exchange Data. J Chem Theory Comput 2021; 17:2619-2629. [PMID: 33780620 DOI: 10.1021/acs.jctc.1c00077] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Amide hydrogen-deuterium exchange (HDX) has long been used to determine regional flexibility and binding sites in proteins; however, the data are too sparse for full structural characterization. Experiments that measure HDX rates, such as HDX-NMR, have far higher throughput compared to structure determination via X-ray crystallography, cryo-EM, or a full suite of NMR experiments. Data from HDX-NMR experiments encode information on the protein structure, making HDX a prime candidate to be supplemented by computational algorithms for protein structure prediction. We have developed a methodology to incorporate HDX-NMR data into ab initio protein structure prediction using the Rosetta software framework to predict structures based on experimental agreement. To demonstrate the efficacy of our algorithm, we examined 38 proteins with HDX-NMR data available, comparing the predicted model with and without the incorporation of HDX data into scoring. The root-mean-square deviation (rmsd, a measure of the average atomic distance between superimposed models) of the predicted model improved by 1.42 Å on average after incorporating the HDX-NMR data into scoring. The average rmsd improvement for the proteins where the selected model rmsd changed after incorporating HDX data was 3.63 Å, including one improvement of more than 11 Å and seven proteins improving by greater than 4 Å, with 12/15 proteins improving overall. Additionally, for independent verification, two proteins that were not part of the original benchmark were scored including HDX data, with a dramatic improvement of the selected model rmsd of nearly 9 Å for one of the proteins. Moreover, we have developed a confidence metric allowing us to successfully identify near-native models in the absence of a native structure. Improvement in model selection with a strong confidence measure demonstrates that protein structure prediction with HDX-NMR is a powerful tool which can be performed with minimal additional computational strain and expense.
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Affiliation(s)
- Daniel R Marzolf
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
| | - Justin T Seffernick
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
| | - Steffen Lindert
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
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17
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Pannecoucke E, Van Trimpont M, Desmet J, Pieters T, Reunes L, Demoen L, Vuylsteke M, Loverix S, Vandenbroucke K, Alard P, Henderikx P, Deroo S, Baatz F, Lorent E, Thiolloy S, Somers K, McGrath Y, Van Vlierberghe P, Lasters I, Savvides SN. Cell-penetrating Alphabody protein scaffolds for intracellular drug targeting. SCIENCE ADVANCES 2021; 7:7/13/eabe1682. [PMID: 33771865 PMCID: PMC7997521 DOI: 10.1126/sciadv.abe1682] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 02/05/2021] [Indexed: 05/02/2023]
Abstract
The therapeutic scope of antibody and nonantibody protein scaffolds is still prohibitively limited against intracellular drug targets. Here, we demonstrate that the Alphabody scaffold can be engineered into a cell-penetrating protein antagonist against induced myeloid leukemia cell differentiation protein MCL-1, an intracellular target in cancer, by grafting the critical B-cell lymphoma 2 homology 3 helix of MCL-1 onto the Alphabody and tagging the scaffold's termini with designed cell-penetration polypeptides. Introduction of an albumin-binding moiety extended the serum half-life of the engineered Alphabody to therapeutically relevant levels, and administration thereof in mouse tumor xenografts based on myeloma cell lines reduced tumor burden. Crystal structures of such a designed Alphabody in complex with MCL-1 and serum albumin provided the structural blueprint of the applied design principles. Collectively, we provide proof of concept for the use of Alphabodies against intracellular disease mediators, which, to date, have remained in the realm of small-molecule therapeutics.
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Affiliation(s)
- Erwin Pannecoucke
- VIB Center for Inflammation Research, 9052 Ghent, Belgium
- Unit for Structural Biology, Department of Biochemistry and Microbiology, Ghent University, 9052 Ghent, Belgium
| | - Maaike Van Trimpont
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | | | - Tim Pieters
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Lindy Reunes
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Lisa Demoen
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | | | | | | | | | | | | | | | | | | | | | | | - Pieter Van Vlierberghe
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | | | - Savvas N Savvides
- VIB Center for Inflammation Research, 9052 Ghent, Belgium.
- Unit for Structural Biology, Department of Biochemistry and Microbiology, Ghent University, 9052 Ghent, Belgium
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18
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Aupič J, Strmšek Ž, Lapenta F, Pahovnik D, Pisanski T, Drobnak I, Ljubetič A, Jerala R. Designed folding pathway of modular coiled-coil-based proteins. Nat Commun 2021; 12:940. [PMID: 33574262 PMCID: PMC7878764 DOI: 10.1038/s41467-021-21185-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 01/13/2021] [Indexed: 12/02/2022] Open
Abstract
Natural proteins are characterised by a complex folding pathway defined uniquely for each fold. Designed coiled-coil protein origami (CCPO) cages are distinct from natural compact proteins, since their fold is prescribed by discrete long-range interactions between orthogonal pairwise-interacting coiled-coil (CC) modules within a single polypeptide chain. Here, we demonstrate that CCPO proteins fold in a stepwise sequential pathway. Molecular dynamics simulations and stopped-flow Förster resonance energy transfer (FRET) measurements reveal that CCPO folding is dominated by the effective intra-chain distance between CC modules in the primary sequence and subsequent folding intermediates, allowing identical CC modules to be employed for multiple cage edges and thus relaxing CCPO cage design requirements. The number of orthogonal modules required for constructing a CCPO tetrahedron can be reduced from six to as little as three different CC modules. The stepwise modular nature of the folding pathway offers insights into the folding of tandem repeat proteins and can be exploited for the design of modular protein structures based on a given set of orthogonal modules.
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Affiliation(s)
- Jana Aupič
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Žiga Strmšek
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
- Interdisciplinary Doctoral Programme in Biomedicine, University of Ljubljana, Ljubljana, Slovenia
| | - Fabio Lapenta
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
- EN-FIST Centre of Excellence, Ljubljana, Slovenia
| | - David Pahovnik
- Department of Polymer Chemistry and Technology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Tomaž Pisanski
- FAMNIT, University of Primorska, Koper, Slovenia
- Institute of Mathematics, Physics and Mechanics, Ljubljana, Slovenia
| | - Igor Drobnak
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Ajasja Ljubetič
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Roman Jerala
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, Ljubljana, Slovenia.
- EN-FIST Centre of Excellence, Ljubljana, Slovenia.
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19
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Kakkis A, Gagnon D, Esselborn J, Britt RD, Tezcan FA. Metal‐Templated Design of Chemically Switchable Protein Assemblies with High‐Affinity Coordination Sites. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Albert Kakkis
- Department of Chemistry and Biochemistry University of California, San Diego 9500 Gilman Drive La Jolla CA 92093 USA
| | - Derek Gagnon
- Department of Chemistry and Biochemistry University of California, San Diego 9500 Gilman Drive La Jolla CA 92093 USA
| | - Julian Esselborn
- Department of Chemistry and Biochemistry University of California, San Diego 9500 Gilman Drive La Jolla CA 92093 USA
| | - R. David Britt
- Department of Chemistry University of California, Davis 1 Shields Avenue Davis CA 95616 USA
| | - F. Akif Tezcan
- Department of Chemistry and Biochemistry University of California, San Diego 9500 Gilman Drive La Jolla CA 92093 USA
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20
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Biggs GS, Klein OJ, Boss SR, Barker PD. Unlocking the Full Evolutionary Potential of Artificial Metalloenzymes Through Direct Metal-Protein Coordination : A review of recent advances for catalyst development. JOHNSON MATTHEY TECHNOLOGY REVIEW 2020. [DOI: 10.1595/205651320x15928204097766] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Generation of artificial metalloenzymes (ArMs) has gained much inspiration from the general understanding of natural metalloenzymes. Over the last decade, a multitude of methods generating transition metal-protein hybrids have been developed and many of these new-to-nature constructs
catalyse reactions previously reserved for the realm of synthetic chemistry. This perspective will focus on ArMs incorporating 4d and 5d transition metals. It aims to summarise the significant advances made to date and asks whether there are chemical strategies, used in nature to optimise
metal catalysts, that have yet to be fully recognised in the synthetic enzyme world, particularly whether artificial enzymes produced to date fully take advantage of the structural and energetic context provided by the protein. Further, the argument is put forward that, based on precedence,
in the majority of naturally evolved metalloenzymes the direct coordination bonding between the metal and the protein scaffold is integral to catalysis. Therefore, the protein can attenuate metal activity by positioning ligand atoms in the form of amino acids, as well as making non-covalent
contributions to catalysis, through intermolecular interactions that pre-organise substrates and stabilise transition states. This highlights the often neglected but crucial element of natural systems that is the energetic contribution towards activating metal centres through protein fold
energy. Finally, general principles needed for a different approach to the formation of ArMs are set out, utilising direct coordination inspired by the activation of an organometallic cofactor upon protein binding. This methodology, observed in nature, delivers true interdependence between
metal and protein. When combined with the ability to efficiently evolve enzymes, new problems in catalysis could be addressed in a faster and more specific manner than with simpler small molecule catalysts.
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Affiliation(s)
- George S. Biggs
- Department of Chemistry, University of Cambridge Lensfield Road, Cambridge, CB2 1EW UK
| | - Oskar James Klein
- Department of Chemistry, University of Cambridge Lensfield Road, Cambridge, CB2 1EW UK
| | - Sally R. Boss
- Department of Chemistry, University of Cambridge Lensfield Road, Cambridge, CB2 1EW UK
| | - Paul D. Barker
- Department of Chemistry, University of Cambridge Lensfield Road, Cambridge, CB2 1EW UK
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21
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Kakkis A, Gagnon D, Esselborn J, Britt RD, Tezcan FA. Metal-Templated Design of Chemically Switchable Protein Assemblies with High-Affinity Coordination Sites. Angew Chem Int Ed Engl 2020; 59:21940-21944. [PMID: 32830423 DOI: 10.1002/anie.202009226] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/13/2020] [Indexed: 11/09/2022]
Abstract
To mimic a hypothetical pathway for protein evolution, we previously tailored a monomeric protein (cyt cb562 ) for metal-mediated self-assembly, followed by re-design of the resulting oligomers for enhanced stability and metal-based functions. We show that a single hydrophobic mutation on the cyt cb562 surface drastically alters the outcome of metal-directed oligomerization to yield a new trimeric architecture, (TriCyt1)3. This nascent trimer was redesigned into second and third-generation variants (TriCyt2)3 and (TriCyt3)3 with increased structural stability and preorganization for metal coordination. The three TriCyt variants combined furnish a unique platform to 1) provide tunable coupling between protein quaternary structure and metal coordination, 2) enable the construction of metal/pH-switchable protein oligomerization motifs, and 3) generate a robust metal coordination site that can coordinate all mid-to-late first-row transition-metal ions with high affinity.
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Affiliation(s)
- Albert Kakkis
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Derek Gagnon
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Julian Esselborn
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - R David Britt
- Department of Chemistry, University of California, Davis, 1 Shields Avenue, Davis, CA, 95616, USA
| | - F Akif Tezcan
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
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22
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Paredes A, Loh BM, Peduzzi OM, Reig AJ, Buettner KM. DNA Cleavage by a De Novo Designed Protein-Titanium Complex. Inorg Chem 2020; 59:11248-11252. [PMID: 32799485 DOI: 10.1021/acs.inorgchem.0c01707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Titanium is one of the most abundant elements on Earth but is commonly thought to have no role in biology because of its propensity to hydrolyze. Nature stabilizes hard Lewis acidic metals from hydrolysis using a variety of mechanisms, providing inspiration for how titanium can be stabilized using biological ligands. The well-characterized Due Ferri single-chain (DFsc) de novo designed protein was developed to bind and stabilize iron and provides a binding site with hard Lewis basic residues able to bind two metal ions. We demonstrate that the DFsc scaffold stably binds 2 equiv of titanium and protects them from unwanted hydrolysis. The Ti4+-DFsc protein complex was tested for its ability to hydrolytically cleave DNA, where it was seen to linearize plasmid DNA in an overnight reaction. Ti4+-DFsc is thus the first example of a functional, soluble titanium-protein complex.
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Affiliation(s)
- Alexander Paredes
- Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States
| | - Brittany M Loh
- Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States
| | - Olivia M Peduzzi
- Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States
| | - Amanda J Reig
- Department of Chemistry, Ursinus College, Collegeville, Pennsylvania 19426, United States
| | - Katherine M Buettner
- Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States
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23
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Song LF, Sengupta A, Merz KM. Thermodynamics of Transition Metal Ion Binding to Proteins. J Am Chem Soc 2020; 142:6365-6374. [PMID: 32141296 DOI: 10.1021/jacs.0c01329] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Modeling the thermodynamics of a transition metal (TM) ion assembly be it in proteins or in coordination complexes affords us a better understanding of the assembly and function of metalloclusters in diverse application areas including metal organic framework design, TM-based catalyst design, the trafficking of TM ions in biological systems, and drug design in metalloprotein platforms. While the structural details of TM ions bound to metalloproteins are generally well understood via experimental and computational approaches, accurate studies describing the thermodynamics of TM ion binding are rare. Herein, we demonstrate that we can obtain accurate structural and absolute binding free energies of Co2+ and Ni2+ to the enzyme glyoxalase I using an optimized 12-6-4 (m12-6-4) potential. Critically, this model simultaneously reproduces the solvation free energy of the individual TM ions and reproduces the thermodynamics of TM ion-ligand coordination as well as the thermodynamics of TM ion binding to a protein active site unlike extant models. We find the incorporation of the thermodynamics associated with protonation state changes for the TM ion (un)binding to be crucial. The high accuracy of m12-6-4 potential in this study presents an accurate route to explore more complicated processes associated with TM cluster assembly and TM ion transport.
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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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25
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Mathieu E, Tolbert AE, Koebke KJ, Tard C, Iranzo O, Penner-Hahn JE, Policar C, Pecoraro V. Rational De Novo Design of a Cu Metalloenzyme for Superoxide Dismutation. Chemistry 2020; 26:249-258. [PMID: 31710732 PMCID: PMC6944188 DOI: 10.1002/chem.201903808] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/04/2019] [Indexed: 01/16/2023]
Abstract
Superoxide dismutases (SODs) are highly efficient enzymes for superoxide dismutation and the first line of defense against oxidative stress. These metalloproteins contain a redox-active metal ion in their active site (Mn, Cu, Fe, Ni) with a tightly controlled reduction potential found in a close range around the optimal value of 0.36 V versus the normal hydrogen electrode (NHE). Rationally designed proteins with well-defined three-dimensional structures offer new opportunities for obtaining functional SOD mimics. Here, we explore four different copper-binding scaffolds: H3 (His3 ), H4 (His4 ), H2 DH (His3 Asp with two His and one Asp in the same plane) and H3 D (His3 Asp with three His in the same plane) by using the scaffold of the de novo protein GRα3 D. EPR and XAS analysis of the resulting copper complexes demonstrates that they are good CuII -bound structural mimics of Cu-only SODs. Furthermore, all the complexes exhibit SOD activity, though three orders of magnitude slower than the native enzyme, making them the first de novo copper SOD mimics.
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Affiliation(s)
- Emilie Mathieu
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
- These authors contributed equally to this work
| | - Audrey E. Tolbert
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48103
- These authors contributed equally to this work
| | - Karl J. Koebke
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48103
| | - Cédric Tard
- LCM, CNRS, Ecole Polytechnique, IP Paris, F-91128 Palaiseau, France
| | - Olga Iranzo
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France
| | | | - Clotilde Policar
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Vincent Pecoraro
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48103
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26
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Engineering Metalloprotein Functions in Designed and Native Scaffolds. Trends Biochem Sci 2019; 44:1022-1040. [DOI: 10.1016/j.tibs.2019.06.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 12/15/2022]
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27
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Marshall LR, Zozulia O, Lengyel-Zhand Z, Korendovych IV. Minimalist de novo Design of Protein Catalysts. ACS Catal 2019; 9:9265-9275. [PMID: 34094654 PMCID: PMC8174531 DOI: 10.1021/acscatal.9b02509] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The field of protein design has grown enormously in the past few decades. In this review we discuss the minimalist approach to design of artificial enzymes, in which protein sequences are created with the minimum number of elements for folding and function. This method relies on identifying starting points in catalytically inert scaffolds for active site installation. The progress of the field from the original helical assemblies of the 1980s to the more complex structures of the present day is discussed, highlighting the variety of catalytic reactions which have been achieved using these methods. We outline the strengths and weaknesses of the minimalist approaches, describe representative design cases and put it in the general context of the de novo design of proteins.
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Affiliation(s)
- Liam R. Marshall
- Department of Chemistry, Syracuse University, 111 College Place, Syracuse, NY 13244, USA
| | - Oleksii Zozulia
- Department of Chemistry, Syracuse University, 111 College Place, Syracuse, NY 13244, USA
| | - Zsofia Lengyel-Zhand
- Department of Chemistry, Syracuse University, 111 College Place, Syracuse, NY 13244, USA
| | - Ivan V. Korendovych
- Department of Chemistry, Syracuse University, 111 College Place, Syracuse, NY 13244, USA
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28
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Towards functional de novo designed proteins. Curr Opin Chem Biol 2019; 52:102-111. [DOI: 10.1016/j.cbpa.2019.06.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/25/2019] [Accepted: 06/06/2019] [Indexed: 12/31/2022]
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29
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Lombardi A, Pirro F, Maglio O, Chino M, DeGrado WF. De Novo Design of Four-Helix Bundle Metalloproteins: One Scaffold, Diverse Reactivities. Acc Chem Res 2019; 52:1148-1159. [PMID: 30973707 DOI: 10.1021/acs.accounts.8b00674] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
De novo protein design represents an attractive approach for testing and extending our understanding of metalloprotein structure and function. Here, we describe our work on the design of DF (Due Ferri or two-iron in Italian), a minimalist model for the active sites of much larger and more complex natural diiron and dimanganese proteins. In nature, diiron and dimanganese proteins protypically bind their ions in 4-Glu, 2-His environments, and they catalyze diverse reactions, ranging from hydrolysis, to O2-dependent chemistry, to decarbonylation of aldehydes. In the design of DF, the position of each atom-including the backbone, the first-shell ligands, the second-shell hydrogen-bonded groups, and the well-packed hydrophobic core-was bespoke using precise mathematical equations and chemical principles. The first member of the DF family was designed to be of minimal size and complexity and yet to display the quintessential elements required for binding the dimetal cofactor. After thoroughly characterizing its structural, dynamic, spectroscopic, and functional properties, we added additional complexity in a rational stepwise manner to achieve increasingly sophisticated catalytic functions, ultimately demonstrating substrate-gated four-electron reduction of O2 to water. We also briefly describe the extension of these studies to the design of proteins that bind nonbiological metal cofactors (a synthetic porphyrin and a tetranuclear cluster), and a Zn2+/proton antiporting membrane protein. Together these studies demonstrate a successful and generally applicable strategy for de novo metalloprotein design, which might indeed mimic the process by which primordial metalloproteins evolved. We began the design process with a highly symmetrical backbone and binding site, by using point-group symmetry to assemble the secondary structures that position the amino acid side chains required for binding. The resulting models provided a rough starting point and initial parameters for the subsequent precise design of the final protein using modern methods of computational protein design. Unless the desired site is itself symmetrical, this process requires reduction of the symmetry or lifting it altogether. Nevertheless, the initial symmetrical structure can be helpful to restrain the search space during assembly of the backbone. Finally, the methods described here should be generally applicable to the design of highly stable and robust catalysts and sensors. There is considerable potential in combining the efficiency and knowledge base associated with homogeneous metal catalysis with the programmability, biocompatibility, and versatility of proteins. While the work reported here focuses on testing and learning the principles of natural metalloproteins by designing and studying proteins one at a time, there is also considerable potential for using designed proteins that incorporate both biological and nonbiological metal ion cofactors for the evolution of novel catalysts.
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Affiliation(s)
- Angela Lombardi
- Department of Chemical Sciences, University of Napoli Federico II, Via Cintia, 26, 80126 Napoli, Italy
| | - Fabio Pirro
- Department of Chemical Sciences, University of Napoli Federico II, Via Cintia, 26, 80126 Napoli, Italy
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, California 94158-9001, United States
| | - Ornella Maglio
- Department of Chemical Sciences, University of Napoli Federico II, Via Cintia, 26, 80126 Napoli, Italy
- IBB, National Research Council, Via Mezzocannone 16, 80134 Napoli, Italy
| | - Marco Chino
- Department of Chemical Sciences, University of Napoli Federico II, Via Cintia, 26, 80126 Napoli, Italy
| | - William F. DeGrado
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, California 94158-9001, United States
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30
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Cardelli C, Nerattini F, Tubiana L, Bianco V, Dellago C, Sciortino F, Coluzza I. General Methodology to Identify the Minimum Alphabet Size for Heteropolymer Design. ADVANCED THEORY AND SIMULATIONS 2019. [DOI: 10.1002/adts.201900031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Chiara Cardelli
- Faculty of PhysicsUniversity of ViennaBoltzmanngasse 5 1090 Vienna Austria
| | | | - Luca Tubiana
- Faculty of PhysicsUniversity of ViennaBoltzmanngasse 5 1090 Vienna Austria
| | - Valentino Bianco
- Faculty of ChemistryChemical Physics DepartmentUniversidad Complutense de Madrid, Plaza de las Ciencias, Ciudad UniversitariaMadrid 28040 Spain
| | - Christoph Dellago
- Faculty of PhysicsUniversity of ViennaBoltzmanngasse 5 1090 Vienna Austria
| | - Francesco Sciortino
- Dipartimento di FisicaSapienza Università di RomaPiazzale Aldo Moro 2 00185 Rome Italy
| | - Ivan Coluzza
- CIC biomaGUNEPaseo Miramon 182 20014 San Sebastian Spain
- IKERBASQUEBasque Foundation for Science48013 Bilbao Spain
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31
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Olajos G, Hetényi A, Wéber E, Szögi T, Fülöp L, Martinek TA. Peripheral cyclic β-amino acids balance the stability and edge-protection of β-sandwiches. Org Biomol Chem 2019; 16:5492-5499. [PMID: 30024580 DOI: 10.1039/c8ob01322e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Engineering water-soluble stand-alone β-sandwich mimetics is a current challenge because of the difficulties associated with tailoring long-range interactions. In this work, single cis-(1R,2S)-2-aminocyclohexanecarboxylic acid mutations were introduced into the edge strands of the eight-stranded β-sandwich mimetic structures from the betabellin family. Temperature-dependent NMR and CD measurements, together with thermodynamic analyses, demonstrated that the modified peripheral strands exhibited an irregular and partially disordered structure but were able to exert sufficient shielding on the hydrophobic core to retain the predominantly β-sandwich structure. Although the frustrated interactions decreased the free energy of unfolding, the temperature of the maximum stabilities increased to or remained at physiologically relevant temperatures. We found that the irregular peripheral strands were able to prevent edge-to-edge association and fibril formation in the aggregation-prone model. These findings establish a β-sandwich stabilization and aggregation inhibition approach, which does not interfere with the pillars of the peptide bond or change the net charge of the peptide.
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Affiliation(s)
- Gábor Olajos
- Institute of Pharmaceutical Analysis, SZTE-MTA Lendület Foldamer Research Group, University of Szeged, Somogyi u. 4., H-6720 Szeged, Hungary. and MTA-SZTE Biomimetic Systems Research Group, University of Szeged, Dóm ter 8., H-6720 Szeged, Hungary
| | - Anasztázia Hetényi
- Department of Medical Chemistry, University of Szeged, Dóm ter 8., H-6720 Szeged, Hungary
| | - Edit Wéber
- Institute of Pharmaceutical Analysis, SZTE-MTA Lendület Foldamer Research Group, University of Szeged, Somogyi u. 4., H-6720 Szeged, Hungary.
| | - Titanilla Szögi
- Department of Medical Chemistry, University of Szeged, Dóm ter 8., H-6720 Szeged, Hungary
| | - Lívia Fülöp
- Department of Medical Chemistry, University of Szeged, Dóm ter 8., H-6720 Szeged, Hungary
| | - Tamás A Martinek
- Institute of Pharmaceutical Analysis, SZTE-MTA Lendület Foldamer Research Group, University of Szeged, Somogyi u. 4., H-6720 Szeged, Hungary. and MTA-SZTE Biomimetic Systems Research Group, University of Szeged, Dóm ter 8., H-6720 Szeged, Hungary
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32
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Khan AZ, Bilal M, Rasheed T, Iqbal HM. Advancements in biocatalysis: From computational to metabolic engineering. CHINESE JOURNAL OF CATALYSIS 2018. [DOI: 10.1016/s1872-2067(18)63144-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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33
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Di Costanzo L, Dutta S, Burley SK. Amino acid modifications for conformationally constraining naturally occurring and engineered peptide backbones: Insights from the Protein Data Bank. Biopolymers 2018; 109:e23230. [PMID: 30368772 DOI: 10.1002/bip.23230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 05/23/2018] [Accepted: 05/24/2018] [Indexed: 01/08/2023]
Abstract
Extensive efforts invested in understanding the rules of protein folding are now being applied, with good effect, in de novo design of proteins/peptides. For proteins containing standard α-amino acids alone, knowledge derived from experimentally determined three-dimensional (3D) structures of proteins and biologically active peptides are available from the Protein Data Bank (PDB), and the Cambridge Structural Database (CSD). These help predict and design protein structures, with reasonable confidence. However, our knowledge of 3D structures of biomolecules containing backbone modified amino acids is still evolving. A major challenge in de novo protein/peptide design concerns the engineering of conformationally constrained molecules with specific structural elements and chemical groups appropriately positioned for biological activity. This review explores four classes of amino acid modifications that constrain protein/peptide backbone structure. Systematic analysis of peptidic molecule structures (eg, bioactive peptides, inhibitors, antibiotics, and designed molecules), containing these backbone-modified amino acids, found in the PDB and CSD are discussed. The review aims to provide structure-function insights that will guide future design of proteins/peptides.
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Affiliation(s)
- Luigi Di Costanzo
- RCSB Protein Data Bank, Center for Integrative Proteomics Research, Rutgers, The State University of New Jersey, Piscataway, NJ, U.S.A
| | - Shuchismita Dutta
- RCSB Protein Data Bank, Center for Integrative Proteomics Research, Rutgers, The State University of New Jersey, Piscataway, NJ, U.S.A.,Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, U.S.A
| | - Stephen K Burley
- RCSB Protein Data Bank, Center for Integrative Proteomics Research, Rutgers, The State University of New Jersey, Piscataway, NJ, U.S.A.,Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, U.S.A.,RCSB Protein Data Bank, San Diego Supercomputer Center, University of California San Diego, La Jolla, CA, U.S.A.,Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, U.S.A
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34
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Koebke KJ, Pecoraro VL. Development of de Novo Copper Nitrite Reductases: Where We Are and Where We Need To Go. ACS Catal 2018; 8:8046-8057. [PMID: 30294504 DOI: 10.1021/acscatal.8b02153] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The development of redox-active metalloprotein catalysts is a challenging objective of de novo protein design. Within this Perspective we detail our efforts to create a redox-active Cu nitrite reductase (NiR) by incorporating Cu into the hydrophobic interior of well-defined three-stranded coiled coils (3SCCs). The scaffold contains three histidine residues that provide a layer of three nitrogen donors that mimic the type 2 catalytic site of NiR. We have found that this strategy successfully produces an active and stable CuNiR model that functions for over 1000 turnovers. Spectroscopic evidence indicates that the Cu(I) site has a lower coordination number in comparison to the enzyme, whereas the Cu(II) geometry may more faithfully reproduce the NiR type 2 center. Mutations at the helical interface successfully produce a hydrogen bond between an interfacial Glu residue and the Culigating His residue, which allows for the tuning of the redox potential over a 100 mV range. We successfully created constructs with as much as a 120-fold improvement from the original design by modifying the steric bulk above or below the Cu binding site. These systems are now the most active water-soluble and stable artificial NiR catalysts yet produced. Several avenues for improving the catalytic efficiency of later designs are detailed within this Perspective, including adjustment of their resting oxidation state, the use of asymmetric scaffolds to allow for single amino acid mutation within the second coordination sphere, and the design of hydrogen-bonding networks to tune residue orientation and electronics. Through these studies the TRI-H system has given insight into the difficulties that arise in creating a de novo redox active enzyme. Work to improve upon this model will provide strategies by which redox-active de novo enzymes may be tuned and detail how native enzymes accomplish catalytic efficiencies through proton gated redox catalysis.
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Affiliation(s)
- Karl J. Koebke
- Department of Chemistry, University of Michigan Ann Arbor, Michigan 48109, United States
| | - Vincent L. Pecoraro
- Department of Chemistry, University of Michigan Ann Arbor, Michigan 48109, United States
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35
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Yuan J, Yuan C, Xie M, Yu L, Bruschweiler-Li L, Brüschweiler R. The Intracellular Loop of the Na +/Ca 2+ Exchanger Contains an "Awareness Ribbon"-Shaped Two-Helix Bundle Domain. Biochemistry 2018; 57:5096-5104. [PMID: 29898361 DOI: 10.1021/acs.biochem.8b00300] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The Na+/Ca2+ exchanger (NCX) is a ubiquitous single-chain membrane protein that plays a major role in regulating the intracellular Ca2+ homeostasis by the counter transport of Na+ and Ca2+ across the cell membrane. Other than its prokaryotic counterpart, which contains only the transmembrane domain and is self-sufficient as an active ion transporter, the eukaryotic NCX protein possesses in addition a large intracellular loop that senses intracellular calcium signals and controls the activation of ion transport across the membrane. This provides a necessary layer of regulation for the more complex function of eukaryotic cells. The Ca2+ sensor in the intracellular loop is known as the Ca2+-binding domain (CBD12). However, how the signaling of the allosteric intracellular Ca2+ binding propagates and results in transmembrane ion transportation still lacks a detailed explanation. Further structural and dynamics characterization of the intracellular loop flanking both sides of CBD12 is therefore imperative. Here, we report the identification and characterization of another structured domain that is N-terminal to CBD12 in the intracellular loop using solution nuclear magnetic resonance (NMR) spectroscopy. The atomistic structure of this domain reveals that two tandem long α-helices, connected by a short linker, form a stable crossover two-helix bundle (THB), resembling an "awareness ribbon". Considering the highly conserved amino acid sequence of the THB domain, the detailed structural and dynamics properties of the THB domain will be common among NCXs from different species and will contribute toward the understanding of the regulatory mechanism of eukaryotic Na+/Ca2+ exchangers.
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Affiliation(s)
- Jiaqi Yuan
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Chunhua Yuan
- Campus Chemical Instrument Center , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Mouzhe Xie
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Lei Yu
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Lei Bruschweiler-Li
- Campus Chemical Instrument Center , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Rafael Brüschweiler
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States.,Campus Chemical Instrument Center , The Ohio State University , Columbus , Ohio 43210 , United States.,Department of Biological Chemistry and Pharmacology , The Ohio State University , Columbus , Ohio 43210 , United States
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36
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Perrella F, Raucci U, Chiariello MG, Chino M, Maglio O, Lombardi A, Rega N. Unveiling the structure of a novel artificial heme-enzyme with peroxidase-like activity: A theoretical investigation. Biopolymers 2018; 109:e23225. [DOI: 10.1002/bip.23225] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 04/11/2018] [Accepted: 04/25/2018] [Indexed: 01/29/2023]
Affiliation(s)
- Fulvio Perrella
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
| | - Umberto Raucci
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
| | - Maria Gabriella Chiariello
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
| | - Marco Chino
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
| | - Ornella Maglio
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
- IBB-CNR, Via Mezzocannone 16; Napoli 80134 Italy
| | - Angela Lombardi
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
| | - Nadia Rega
- Dipartimento di Scienze Chimiche; Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, via Cintia; Napoli 80126 Italy
- CRIB Center for Advanced Biomaterials for Healthcare, Piazzale Tecchio; Napoli 80125 Italy
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37
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Isogai Y, Takao E, Nakamura R, Kato M, Kawabata S. Supramolecular polymer formation by a
de novo
hemoprotein with a synthetic diheme compound. FEBS Open Bio 2018; 8:940-946. [PMID: 29928574 PMCID: PMC5986056 DOI: 10.1002/2211-5463.12424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/08/2018] [Accepted: 03/28/2018] [Indexed: 11/11/2022] Open
Abstract
Proteins are attractive materials for supramolecular chemistry due to their multifunctionality and self‐organization ability. In this work, we synthesized a diheme compound, in which two iron‐protoporphyrin IX molecules are associated via a linker chain, and introduced it into a de novo designed four‐helix bundle protein with two heme‐binding sites. The protein gradually bound the diheme compound by bis‐histidyl ligation and formed supramolecular polymers. Polymer formation was observed by atomic force microscopy (AFM), which revealed the highly branched, dendritic forms of the fibrous architecture. The present results may open a pathway toward nanowire construction with de novo heme‐proteins.
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Affiliation(s)
- Yasuhiro Isogai
- Department of Pharmaceutical Engineering Toyama Prefectural University Imizu Japan
| | - Eisuke Takao
- Graduate School of Life Sciences Ritsumeikan University Kusatsu Japan
| | - Ryuta Nakamura
- Department of Pharmaceutical Engineering Toyama Prefectural University Imizu Japan
| | - Minoru Kato
- Graduate School of Life Sciences Ritsumeikan University Kusatsu Japan
| | - Shigeki Kawabata
- Department of Liberal Arts and Sciences Toyama Prefectural University Imizu Japan
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38
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Panganiban B, Qiao B, Jiang T, DelRe C, Obadia MM, Nguyen TD, Smith AAA, Hall A, Sit I, Crosby MG, Dennis PB, Drockenmuller E, Olvera de la Cruz M, Xu T. Random heteropolymers preserve protein function in foreign environments. Science 2018; 359:1239-1243. [DOI: 10.1126/science.aao0335] [Citation(s) in RCA: 142] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 01/25/2018] [Indexed: 12/25/2022]
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39
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Bostick CD, Mukhopadhyay S, Pecht I, Sheves M, Cahen D, Lederman D. Protein bioelectronics: a review of what we do and do not know. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:026601. [PMID: 29303117 DOI: 10.1088/1361-6633/aa85f2] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We review the status of protein-based molecular electronics. First, we define and discuss fundamental concepts of electron transfer and transport in and across proteins and proposed mechanisms for these processes. We then describe the immobilization of proteins to solid-state surfaces in both nanoscale and macroscopic approaches, and highlight how different methodologies can alter protein electronic properties. Because immobilizing proteins while retaining biological activity is crucial to the successful development of bioelectronic devices, we discuss this process at length. We briefly discuss computational predictions and their connection to experimental results. We then summarize how the biological activity of immobilized proteins is beneficial for bioelectronic devices, and how conductance measurements can shed light on protein properties. Finally, we consider how the research to date could influence the development of future bioelectronic devices.
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Affiliation(s)
- Christopher D Bostick
- Department of Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506, United States of America. Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, United States of America
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40
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Zhang SQ, Chino M, Liu L, Tang Y, Hu X, DeGrado WF, Lombardi A. De Novo Design of Tetranuclear Transition Metal Clusters Stabilized by Hydrogen-Bonded Networks in Helical Bundles. J Am Chem Soc 2018; 140:1294-1304. [PMID: 29249157 PMCID: PMC5860638 DOI: 10.1021/jacs.7b08261] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
De novo design provides an attractive approach to test the mechanism by which metalloproteins define the geometry and reactivity of their metal ion cofactors. While there has been considerable progress in designing proteins that bind transition metal ions including iron-sulfur clusters, the design of tetranuclear clusters with oxygen-rich environments has not been accomplished. Here, we describe the design of tetranuclear clusters, consisting of four Zn2+ and four carboxylate oxygens situated at the vertices of a distorted cube-like structure. The tetra-Zn2+ clusters are bound at a buried site within a four-helix bundle, with each helix donating a single carboxylate (Glu or Asp) and imidazole (His) ligand, as well as second- and third-shell ligands. Overall, the designed site consists of four Zn2+ and 16 polar side chains in a fully connected hydrogen-bonded network. The designed proteins have apolar cores at the top and bottom of the bundle, which drive the assembly of the liganding residues near the center of the bundle. The steric bulk of the apolar residues surrounding the binding site was varied to determine how subtle changes in helix-helix packing affect the binding site. The crystal structures of two of four proteins synthesized were in good agreement with the overall design; both formed a distorted cuboidal site stabilized by flanking second- and third-shell interactions that stabilize the primary ligands. A third structure bound a single Zn2+ in an unanticipated geometry, and the fourth bound multiple Zn2+ at multiple sites at partial occupancy. The metal-binding and conformational properties of the helical bundles in solution, probed by circular dichroism spectroscopy, analytical ultracentrifugation, and NMR, were consistent with the crystal structures.
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Affiliation(s)
- Shao-Qing Zhang
- Department of Chemistry, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104-6396, United States
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA 94158-9001, United States
| | - Marco Chino
- Department of Chemical Sciences, University of Napoli “Federico II”, Via Cintia, 46, I-80126 Napoli, Italy
| | - Lijun Liu
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA 94158-9001, United States
- DLX Scientific, Lawrence, KS 66049, United States
| | - Youzhi Tang
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA 94158-9001, United States
- College of Veterinary Medicine, South China Agricultural University, Guangdong 510642, China
| | - Xiaozhen Hu
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA 94158-9001, United States
| | - William F. DeGrado
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA 94158-9001, United States
| | - Angela Lombardi
- Department of Chemical Sciences, University of Napoli “Federico II”, Via Cintia, 46, I-80126 Napoli, Italy
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41
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Koebke KJ, Yu F, Salerno E, Van Stappen C, Tebo AG, Penner-Hahn JE, Pecoraro VL. Modifying the Steric Properties in the Second Coordination Sphere of Designed Peptides Leads to Enhancement of Nitrite Reductase Activity. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201712757] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Karl J. Koebke
- Department of Chemistry; University of Michigan; Ann Arbor MI 48109 USA
| | - Fangting Yu
- Department of Chemistry; University of Michigan; Ann Arbor MI 48109 USA
| | - Elvin Salerno
- Department of Chemistry; University of Michigan; Ann Arbor MI 48109 USA
| | - Casey Van Stappen
- Department of Chemistry; University of Michigan; Ann Arbor MI 48109 USA
| | - Alison G. Tebo
- Department of Chemistry; University of Michigan; Ann Arbor MI 48109 USA
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42
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Koebke KJ, Yu F, Salerno E, Van Stappen C, Tebo AG, Penner-Hahn JE, Pecoraro VL. Modifying the Steric Properties in the Second Coordination Sphere of Designed Peptides Leads to Enhancement of Nitrite Reductase Activity. Angew Chem Int Ed Engl 2018; 57:3954-3957. [PMID: 29316146 DOI: 10.1002/anie.201712757] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Indexed: 11/10/2022]
Abstract
Protein design is a useful strategy to interrogate the protein structure-function relationship. We demonstrate using a highly modular 3-stranded coiled coil (TRI-peptide system) that a functional type 2 copper center exhibiting copper nitrite reductase (NiR) activity exhibits the highest homogeneous catalytic efficiency under aqueous conditions for the reduction of nitrite to NO and H2 O. Modification of the amino acids in the second coordination sphere of the copper center increases the nitrite reductase activity up to 75-fold compared to previously reported systems. We find also that steric bulk can be used to enforce a three-coordinate CuI in a site, which tends toward two-coordination with decreased steric bulk. This study demonstrates the importance of the second coordination sphere environment both for controlling metal-center ligation and enhancing the catalytic efficiency of metalloenzymes and their analogues.
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Affiliation(s)
- Karl J Koebke
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Fangting Yu
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Elvin Salerno
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Casey Van Stappen
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alison G Tebo
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Vincent L Pecoraro
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
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43
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Niesen MJM, Marshall SS, Miller TF, Clemons WM. Improving membrane protein expression by optimizing integration efficiency. J Biol Chem 2017; 292:19537-19545. [PMID: 28918393 DOI: 10.1074/jbc.m117.813469] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 09/12/2017] [Indexed: 12/22/2022] Open
Abstract
The heterologous overexpression of integral membrane proteins in Escherichia coli often yields insufficient quantities of purifiable protein for applications of interest. The current study leverages a recently demonstrated link between co-translational membrane integration efficiency and protein expression levels to predict protein sequence modifications that improve expression. Membrane integration efficiencies, obtained using a coarse-grained simulation approach, robustly predicted effects on expression of the integral membrane protein TatC for a set of 140 sequence modifications, including loop-swap chimeras and single-residue mutations distributed throughout the protein sequence. Mutations that improve simulated integration efficiency were 4-fold enriched with respect to improved experimentally observed expression levels. Furthermore, the effects of double mutations on both simulated integration efficiency and experimentally observed expression levels were cumulative and largely independent, suggesting that multiple mutations can be introduced to yield higher levels of purifiable protein. This work provides a foundation for a general method for the rational overexpression of integral membrane proteins based on computationally simulated membrane integration efficiencies.
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Affiliation(s)
- Michiel J M Niesen
- From the Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Stephen S Marshall
- From the Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Thomas F Miller
- From the Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - William M Clemons
- From the Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
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44
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Abstract
In vitro, computational, and theoretical studies of protein folding have converged to paint a rich and complex energy landscape. This landscape is sensitively modulated by environmental conditions and subject to evolutionary pressure on protein function. Of these environments, none is more complex than the cell itself, where proteins function in the cytosol, in membranes, and in different compartments. A wide variety of kinetic and thermodynamics experiments, ranging from single-molecule studies to jump kinetics and from nuclear magnetic resonance to imaging on the microscope, have elucidated how protein energy landscapes facilitate folding and how they are subject to evolutionary constraints and environmental perturbation. Here we review some recent developments in the field and refer the reader to some original work and additional reviews that cover this broad topic in protein science.
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Affiliation(s)
- Martin Gruebele
- Center for Biophysics and Quantitative Biology, University of Illinois, Urbana, Illinois 61801; , .,Department of Chemistry, University of Illinois, Urbana, Illinois 61801; .,Department of Physics, University of Illinois, Urbana, Illinois 61801
| | - Kapil Dave
- Center for Biophysics and Quantitative Biology, University of Illinois, Urbana, Illinois 61801; ,
| | - Shahar Sukenik
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801;
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45
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Proteins evolve on the edge of supramolecular self-assembly. Nature 2017; 548:244-247. [PMID: 28783726 DOI: 10.1038/nature23320] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 06/20/2017] [Indexed: 12/12/2022]
Abstract
The self-association of proteins into symmetric complexes is ubiquitous in all kingdoms of life. Symmetric complexes possess unique geometric and functional properties, but their internal symmetry can pose a risk. In sickle-cell disease, the symmetry of haemoglobin exacerbates the effect of a mutation, triggering assembly into harmful fibrils. Here we examine the universality of this mechanism and its relation to protein structure geometry. We introduced point mutations solely designed to increase surface hydrophobicity among 12 distinct symmetric complexes from Escherichia coli. Notably, all responded by forming supramolecular assemblies in vitro, as well as in vivo upon heterologous expression in Saccharomyces cerevisiae. Remarkably, in four cases, micrometre-long fibrils formed in vivo in response to a single point mutation. Biophysical measurements and electron microscopy revealed that mutants self-assembled in their folded states and so were not amyloid-like. Structural examination of 73 mutants identified supramolecular assembly hot spots predictable by geometry. A subsequent structural analysis of 7,471 symmetric complexes showed that geometric hot spots were buffered chemically by hydrophilic residues, suggesting a mechanism preventing mis-assembly of these regions. Thus, point mutations can frequently trigger folded proteins to self-assemble into higher-order structures. This potential is counterbalanced by negative selection and can be exploited to design nanomaterials in living cells.
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46
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Ganguly A, Luong TQ, Brylski O, Dirkmann M, Möller D, Ebbinghaus S, Schulz F, Winter R, Sanchez-Garcia E, Thiel W. Elucidation of the Catalytic Mechanism of a Miniature Zinc Finger Hydrolase. J Phys Chem B 2017. [DOI: 10.1021/acs.jpcb.7b05027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Abir Ganguly
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
| | - Trung Quan Luong
- Fakultät
für Chemie und Chemische Biologie, Physikalische Chemie I, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Oliver Brylski
- Fakultät
für Chemie und Biochemie, Physikalische Chemie II, Ruhr-Universität Bochum, 44780, Bochum, Germany
| | - Michael Dirkmann
- Fakultät
für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - David Möller
- Fakultät
für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Simon Ebbinghaus
- Fakultät
für Chemie und Biochemie, Physikalische Chemie II, Ruhr-Universität Bochum, 44780, Bochum, Germany
| | - Frank Schulz
- Fakultät
für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Roland Winter
- Fakultät
für Chemie und Chemische Biologie, Physikalische Chemie I, Technische Universität Dortmund, 44227 Dortmund, Germany
| | | | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
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47
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Ma C, Liang C, Wang Y, Pan M, Jiang Q, Shi C. Combinatorial Library Based on Restriction Enzyme-mediated Modular Assembly. ACS COMBINATORIAL SCIENCE 2017; 19:351-355. [PMID: 28437612 DOI: 10.1021/acscombsci.6b00145] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Combinatorial approaches in directed evolution were proven to be more efficient for exploring sequence space and innovating function of protein. Here, we presented the modular assembly of secondary structures (MASS) for constructing a combinatorial library. In this approach, secondary structure elements were extracted from natural existing protein. The common linkers were flanking secondary structure elements, and then secondary structure elements were digested by Hinf I restriction endonuclease that was used in the construction of combinatorial library for the first time. The digested DNA fragments were randomly ligated in the sense orientation, then in sequence to be amplified by PCR and transformation. This approach showed that different DNA fragments without homologous sequences could be randomly assembled to create significant sequence space. With the structure analysis of recombinants, it would be beneficial to the rational design, even to the design of protein de novo, and to evolve any genetic part or circuit.
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Affiliation(s)
- Cuiping Ma
- Key
Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education,
College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Chao Liang
- Key
Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education,
College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Yifan Wang
- Key
Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education,
College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Mei Pan
- Key
Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education,
College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Qianqian Jiang
- Key
Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education,
College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Chao Shi
- College
of Life Sciences, Qingdao University, Qingdao, 266071, P.R. China
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Ruckthong L, Peacock AFA, Pascoe CE, Hemmingsen L, Stuckey JA, Pecoraro VL. d-Cysteine Ligands Control Metal Geometries within De Novo Designed Three-Stranded Coiled Coils. Chemistry 2017; 23:8232-8243. [PMID: 28384393 DOI: 10.1002/chem.201700660] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Indexed: 12/31/2022]
Abstract
Although metal ion binding to naturally occurring l-amino acid proteins is well documented, understanding the impact of the opposite chirality (d-)amino acids on the structure and stereochemistry of metals is in its infancy. We examine the effect of a d-configuration cysteine within a designed l-amino acid three-stranded coiled coil in order to enforce a precise coordination number on a metal center. The d chirality does not alter the native fold, but the side-chain re-orientation modifies the sterics of the metal binding pocket. l-Cys side chains within the coiled-coil structure have previously been shown to rotate substantially from their preferred positions in the apo structure to create a binding site for a tetra-coordinate metal ion. However, here we show by X-ray crystallography that d-Cys side chains are preorganized within a suitable geometry to bind such a ligand. This is confirmed by comparison of the structure of ZnII Cl(CSL16D C)32- to the published structure of ZnII (H2 O)(GRAND-CSL12AL16L C)3- . Moreover, spectroscopic analysis indicates that the CdII geometry observed by using l-Cys ligands (a mixture of three- and four-coordinate CdII ) is altered to a single four-coordinate species when d-Cys is present. This work opens a new avenue for the control of the metal site environment in man-made proteins, by simply altering the binding ligand with its mirror-imaged d configuration. Thus, the use of non-coded amino acids in the coordination sphere of a metal promises to be a powerful tool for controlling the properties of future metalloproteins.
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Affiliation(s)
- Leela Ruckthong
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, USA
- Present address: Department Chemistry, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bang Mod, ThungKhru, Bangkok, 10140, Thailand
| | - Anna F A Peacock
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, USA
- Present address: School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Cherilyn E Pascoe
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Lars Hemmingsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, København Ø, Denmark
| | - Jeanne A Stuckey
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Vincent L Pecoraro
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, USA
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Coluzza I. Computational protein design: a review. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:143001. [PMID: 28140371 DOI: 10.1088/1361-648x/aa5c76] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Proteins are one of the most versatile modular assembling systems in nature. Experimentally, more than 110 000 protein structures have been identified and more are deposited every day in the Protein Data Bank. Such an enormous structural variety is to a first approximation controlled by the sequence of amino acids along the peptide chain of each protein. Understanding how the structural and functional properties of the target can be encoded in this sequence is the main objective of protein design. Unfortunately, rational protein design remains one of the major challenges across the disciplines of biology, physics and chemistry. The implications of solving this problem are enormous and branch into materials science, drug design, evolution and even cryptography. For instance, in the field of drug design an effective computational method to design protein-based ligands for biological targets such as viruses, bacteria or tumour cells, could give a significant boost to the development of new therapies with reduced side effects. In materials science, self-assembly is a highly desired property and soon artificial proteins could represent a new class of designable self-assembling materials. The scope of this review is to describe the state of the art in computational protein design methods and give the reader an outline of what developments could be expected in the near future.
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Affiliation(s)
- Ivan Coluzza
- Computational Physics, Faculty of Physics, University of Vienna, Vienna, Austria
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50
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Cangelosi V, Ruckthong L, Pecoraro VL. Lead(II) Binding in Natural and Artificial Proteins. Met Ions Life Sci 2017; 17:/books/9783110434330/9783110434330-010/9783110434330-010.xml. [PMID: 28731303 PMCID: PMC5771651 DOI: 10.1515/9783110434330-010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This article describes recent attempts to understand the biological chemistry of lead using a synthetic biology approach. Lead binds to a variety of different biomolecules ranging from enzymes to regulatory and signaling proteins to bone matrix. We have focused on the interactions of this element in thiolate-rich sites that are found in metalloregulatory proteins such as Pbr, Znt, and CadC and in enzymes such as δ-aminolevulinic acid dehydratase (ALAD). In these proteins, Pb(II) is often found as a homoleptic and hemidirectic Pb(II)(SR)3- complex. Using first principles of biophysics, we have developed relatively short peptides that can associate into three-stranded coiled coils (3SCCs), in which a cysteine group is incorporated into the hydrophobic core to generate a (cysteine)3 binding site. We describe how lead may be sequestered into these sites, the characteristic spectral features may be observed for such systems and we provide crystallographic insight on metal binding. The Pb(II)(SR)3- that is revealed within these α-helical assemblies forms a trigonal pyramidal structure (having an endo orientation) with distinct conformations than are also found in natural proteins (having an exo conformation). This structural insight, combined with 207Pb NMR spectroscopy, suggests that while Pb(II) prefers hemidirected Pb(II)(SR)3- scaffolds regardless of the protein fold, the way this is achieved within α-helical systems is different than in β-sheet or loop regions of proteins. These interactions between metal coordination preference and protein structural preference undoubtedly are exploited in natural systems to allow for protein conformation changes that define function. Thus, using a design approach that separates the numerous factors that lead to stable natural proteins allows us to extract fundamental concepts on how metals behave in biological systems.
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