1
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Gholampour-Faroji N, Hemmat J, Haddad-Mashadrizeh A, Asoodeh A. Characterization, structural, and evolutionary analysis of an extremophilic GH5 endoglucanase from Bacillus sp. G131: Insights from ancestral sequence reconstruction. Int J Biol Macromol 2024; 277:134311. [PMID: 39094869 DOI: 10.1016/j.ijbiomac.2024.134311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 07/16/2024] [Accepted: 07/28/2024] [Indexed: 08/04/2024]
Abstract
Nature has developed extremozymes that catalyze complex reaction processes in extreme environmental conditions. Accordingly, a combined approach consisting of extremozyme screening, ancestral sequence resurrection (ASR), and molecular dynamic simulation was utilized to construct a developed endoglucanase. The primary experimental and in-silico data led to the prediction of a hypothetical sequence of endoglucanase (EG5-G131) using Bacillus sp. G131 confirmed by amplification and sequencing. EG5-G131 exhibited noticeable stability in a broad-pH range, several detergents, organic solvents, and temperatures up to 80 °C. The molecular weight, Vmax, and Km of the purified endoglucanase were estimated to be 36 kDa, 4.32 μmol/min, and 23.62 mg/ml, respectively. The calculated thermodynamic parameters for EG5-G131 confirmed its intrinsic thermostability. Computational analysis revealed Glu142 and Glu230 as active-site residues of the enzyme. Furthermore, the enzyme remained bound to cellotetraose at 298 K, 333 K, 343 K, and 353 K for 300 ns, consistent with our experimental data. ASR of EG5-G131 led to the introduction of ancestral ANC204 and ANC205, which show similar thermodynamic characteristics with the last Firmicute common ancestor. Finally, truncating loops from the N-terminal of two sequences created two variants with desirable thermal stability, suggesting the evolutionary deciphering of the functional domain of the GH5 family in Bacillus sp. G131.
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Affiliation(s)
- Nazanin Gholampour-Faroji
- Biotechnology Department, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran
| | - Jafar Hemmat
- Biotechnology Department, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran.
| | - Aliakbar Haddad-Mashadrizeh
- Industrial Biotechnology Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran.
| | - Ahmad Asoodeh
- Industrial Biotechnology Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran; Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
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2
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Nguyen TA, Lee C. Thr-to-Ala Mutation Leads to a Larger Aromatic Pair and Reduced Packing Density in α1,α3-Helices during Thioredoxin Cold Adaptation. ACS OMEGA 2024; 9:10812-10824. [PMID: 38463323 PMCID: PMC10918799 DOI: 10.1021/acsomega.3c09806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/18/2024] [Accepted: 02/08/2024] [Indexed: 03/12/2024]
Abstract
This study investigates the impact of aromatic-aromatic interactions on the cold adaptation of thioredoxin (Trx), a small redox protein with a conserved Trx-fold structure. Two Trx orthologs, one from the psychrophilic Arctic bacterium Sphingomonas sp. (SpTrx) and the other from the mesophilic Escherichia coli (EcTrx), display distinct aromatic interactions in their α1,α3-helices. SpTrx features a larger Trp11-Phe69 pair, while EcTrx employs a smaller Phe12-Tyr70 pair along with an additional Asp9-Thr66 hydrogen bond. Smaller aromatic residues in SpTrx (Phe-Phe or Phe-Tyr pair) lead to decreased thermal and thermodynamic stabilities, increased conformational flexibility, and reduced enzyme activity. In contrast, EcTrx's thermal stability is primarily influenced by the larger Trp residue, especially in the more hydrophobic Trp-Phe pair compared to the Trp-Tyr pair. Both SpTrx and EcTrx exhibit a strengthening of the Asp-Thr hydrogen bond by a Phe-Tyr pair and a weakening by a Trp-Phe pair. Additionally, the Asp8-Thr65 hydrogen bond in SpTrx contributes to the destabilization of the Phe-Phe pair. Molecular dynamics simulations of SpTrx indicate that a smaller aromatic pair or the Asp-Thr hydrogen bond in the α1,α3-helices further destabilizes the α2-helix across the central β-sheet. Our results suggest that the Thr-to-Ala mutation destabilizes the α1,α3-helices, resulting in a larger aromatic pair and reduced packing density in psychrophilic Trxs during cold adaptation. These findings enhance our understanding of Trx's adaptation to colder temperatures.
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Affiliation(s)
- Tu Anh Nguyen
- Department of Biomedical
Science and Center for Bio-Nanomaterials, Daegu University, Gyeongsan 38453, South Korea
| | - ChangWoo Lee
- Department of Biomedical
Science and Center for Bio-Nanomaterials, Daegu University, Gyeongsan 38453, South Korea
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3
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Romero ML, Garcia Seisdedos H, Ibarra‐Molero B. Active site center redesign increases protein stability preserving catalysis in thioredoxin. Protein Sci 2022; 31:e4417. [PMID: 39287965 PMCID: PMC9601870 DOI: 10.1002/pro.4417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/15/2022] [Accepted: 07/31/2022] [Indexed: 11/08/2022]
Abstract
The stabilization of natural proteins is a long-standing desired goal in protein engineering. Optimizing the hydrophobicity of the protein core often results in extensive stability enhancements. However, the presence of totally or partially buried catalytic charged residues, essential for protein function, has limited the applicability of this strategy. Here, focusing on the thioredoxin, we aimed to augment protein stability by removing buried charged residues in the active site without loss of catalytic activity. To this end, we performed a charged-to-hydrophobic substitution of a buried and functional group, resulting in a significant stability increase yet abolishing catalytic activity. Then, to simulate the catalytic role of the buried ionizable group, we designed a combinatorial library of variants targeting a set of seven surface residues adjacent to the active site. Notably, more than 50% of the library variants restored, to some extent, the catalytic activity. The combination of experimental study of 2% of the library with the prediction of the whole mutational space by partial least squares regression revealed that a single point mutation at the protein surface is sufficient to fully restore the catalytic activity without thermostability cost. As a result, we engineered one of the highest thermal stabilities reported for a protein with a natural occurring fold (137°C). Further, our hyperstable variant preserves the catalytic activity both in vitro and in vivo.
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Affiliation(s)
- Maria Luisa Romero
- Departamento de Química FísicaUniversidad de GranadaGranada
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Center for Systems Biology DresdenDresdenGermany
| | - Hector Garcia Seisdedos
- Departamento de Química FísicaUniversidad de GranadaGranada
- Department of Structural BiologyWeizmann Institute of ScienceRehovotIsrael
- Department of Structural BiologyInstituto de Biologia Molecular de Barcelona (IBMB‐CSIC)BarcelonaSpain
| | - Beatriz Ibarra‐Molero
- Departamento de Química FísicaUniversidad de GranadaGranada
- Department of Structural BiologyInstituto de Biologia Molecular de Barcelona (IBMB‐CSIC)BarcelonaSpain
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4
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Karlsson E, Sorgenfrei FA, Andersson E, Dogan J, Jemth P, Chi CN. The dynamic properties of a nuclear coactivator binding domain are evolutionarily conserved. Commun Biol 2022; 5:286. [PMID: 35354917 PMCID: PMC8967867 DOI: 10.1038/s42003-022-03217-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 03/02/2022] [Indexed: 12/21/2022] Open
Abstract
Evolution of proteins is constrained by their structure and function. While there is a consensus that the plasticity of intrinsically disordered proteins relaxes the structural constraints on evolution there is a paucity of data on the molecular details of these processes. The Nuclear Coactivator Binding Domain (NCBD) from CREB-binding protein is a protein interaction domain, which contains a hydrophobic core but is not behaving as a typical globular domain, and has been described as 'molten-globule like'. The highly dynamic properties of NCBD makes it an interesting model system for evolutionary structure-function investigation of intrinsically disordered proteins. We have here compared the structure and biophysical properties of an ancient version of NCBD present in a bilaterian animal ancestor living around 600 million years ago with extant human NCBD. Using a combination of NMR spectroscopy, circular dichroism and kinetics we show that although NCBD has increased its thermodynamic stability, it has retained its dynamic biophysical properties in the ligand-free state in the evolutionary lineage leading from the last common bilaterian ancestor to humans. Our findings suggest that the dynamic properties of NCBD have been maintained by purifying selection and thus are important for its function, which includes mediating several distinct protein-protein interactions.
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Affiliation(s)
- Elin Karlsson
- Department of Medical Biochemistry and Microbiology, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden
| | - Frieda A Sorgenfrei
- Department of Medical Biochemistry and Microbiology, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden.,acib GmbH, Krenngasse 37, 8010 Graz c/o University of Graz, Institute of Chemistry, NAWI Graz, BioTechMed Graz, Heinrichstrasse 28, 8010, Graz, Austria
| | - Eva Andersson
- Department of Medical Biochemistry and Microbiology, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden
| | - Jakob Dogan
- Department of Medical Biochemistry and Microbiology, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden
| | - Per Jemth
- Department of Medical Biochemistry and Microbiology, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden.
| | - Celestine N Chi
- Department of Medical Biochemistry and Microbiology, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden. .,Department of Pharmaceutical Biosciences, Uppsala University, BMC Box 582, SE-75123, Uppsala, Sweden.
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5
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Gamiz-Arco G, Risso VA, Gaucher EA, Gavira JA, Naganathan AN, Ibarra-Molero B, Sanchez-Ruiz JM. Combining Ancestral Reconstruction with Folding-Landscape Simulations to Engineer Heterologous Protein Expression. J Mol Biol 2021; 433:167321. [PMID: 34687715 DOI: 10.1016/j.jmb.2021.167321] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/01/2021] [Accepted: 10/17/2021] [Indexed: 11/30/2022]
Abstract
Obligate symbionts typically exhibit high evolutionary rates. Consequently, their proteins may differ considerably from their modern and ancestral homologs in terms of both sequence and properties, thus providing excellent models to study protein evolution. Also, obligate symbionts are challenging to culture in the lab and proteins from uncultured organisms must be produced in heterologous hosts using recombinant DNA technology. Obligate symbionts thus replicate a fundamental scenario of metagenomics studies aimed at the functional characterization and biotechnological exploitation of proteins from the bacteria in soil. Here, we use the thioredoxin from Candidatus Photodesmus katoptron, an uncultured symbiont of flashlight fish, to explore evolutionary and engineering aspects of protein folding in heterologous hosts. The symbiont protein is a standard thioredoxin in terms of 3D-structure, stability and redox activity. However, its folding outside the original host is severely impaired, as shown by a very slow refolding in vitro and an inefficient expression in E. coli that leads mostly to insoluble protein. By contrast, resurrected Precambrian thioredoxins express efficiently in E. coli, plausibly reflecting an ancient adaptation to unassisted folding. We have used a statistical-mechanical model of the folding landscape to guide back-to-ancestor engineering of the symbiont protein. Remarkably, we find that the efficiency of heterologous expression correlates with the in vitro (i.e., unassisted) folding rate and that the ancestral expression efficiency can be achieved with only 1-2 back-to-ancestor replacements. These results demonstrate a minimal-perturbation, sequence-engineering approach to rescue inefficient heterologous expression which may potentially be useful in metagenomics efforts targeting recent adaptations.
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Affiliation(s)
- Gloria Gamiz-Arco
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain
| | - Valeria A Risso
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain
| | - Eric A Gaucher
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA
| | - Jose A Gavira
- Laboratorio de Estudios Cristalograficos, Instituto Andaluz de Ciencias de la Tierra, CSIC, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Avenida de las Palmeras 4, Armilla, Granada 18100, Spain. https://twitter.com/Gavirius
| | - Athi N Naganathan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India.
| | - Beatriz Ibarra-Molero
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain.
| | - Jose M Sanchez-Ruiz
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain.
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6
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Pinto GP, Corbella M, Demkiv AO, Kamerlin SCL. Exploiting enzyme evolution for computational protein design. Trends Biochem Sci 2021; 47:375-389. [PMID: 34544655 DOI: 10.1016/j.tibs.2021.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/18/2021] [Accepted: 08/24/2021] [Indexed: 11/15/2022]
Abstract
Recent years have seen an explosion of interest in understanding the physicochemical parameters that shape enzyme evolution, as well as substantial advances in computational enzyme design. This review discusses three areas where evolutionary information can be used as part of the design process: (i) using ancestral sequence reconstruction (ASR) to generate new starting points for enzyme design efforts; (ii) learning from how nature uses conformational dynamics in enzyme evolution to mimic this process in silico; and (iii) modular design of enzymes from smaller fragments, again mimicking the process by which nature appears to create new protein folds. Using showcase examples, we highlight the importance of incorporating evolutionary information to continue to push forward the boundaries of enzyme design studies.
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Affiliation(s)
- Gaspar P Pinto
- Department of Chemistry - BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Marina Corbella
- Department of Chemistry - BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Andrey O Demkiv
- Department of Chemistry - BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
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7
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Non-conservation of folding rates in the thioredoxin family reveals degradation of ancestral unassisted-folding. Biochem J 2020; 476:3631-3647. [PMID: 31750876 PMCID: PMC6906118 DOI: 10.1042/bcj20190739] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/19/2019] [Accepted: 11/21/2019] [Indexed: 01/04/2023]
Abstract
Evolution involves not only adaptation, but also the degradation of superfluous features. Many examples of degradation at the morphological level are known (vestigial organs, for instance). However, the impact of degradation on molecular evolution has been rarely addressed. Thioredoxins serve as general oxidoreductases in all cells. Here, we report extensive mutational analyses on the folding of modern and resurrected ancestral bacterial thioredoxins. Contrary to claims from recent literature, in vitro folding rates in the thioredoxin family are not evolutionarily conserved, but span at least a ∼100-fold range. Furthermore, modern thioredoxin folding is often substantially slower than ancestral thioredoxin folding. Unassisted folding, as probed in vitro, thus emerges as an ancestral vestigial feature that underwent degradation, plausibly upon the evolutionary emergence of efficient cellular folding assistance. More generally, our results provide evidence that degradation of ancestral features shapes, not only morphological evolution, but also the evolution of individual proteins.
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8
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Babkova P, Dunajova Z, Chaloupkova R, Damborsky J, Bednar D, Marek M. Structures of hyperstable ancestral haloalkane dehalogenases show restricted conformational dynamics. Comput Struct Biotechnol J 2020; 18:1497-1508. [PMID: 32637047 PMCID: PMC7327271 DOI: 10.1016/j.csbj.2020.06.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 12/30/2022] Open
Abstract
Ancestral sequence reconstruction is a powerful method for inferring ancestors of modern enzymes and for studying structure-function relationships of enzymes. We have previously applied this approach to haloalkane dehalogenases (HLDs) from the subfamily HLD-II and obtained thermodynamically highly stabilized enzymes (ΔT m up to 24 °C), showing improved catalytic properties. Here we combined crystallographic structural analysis and computational molecular dynamics simulations to gain insight into the mechanisms by which ancestral HLDs became more robust enzymes with novel catalytic properties. Reconstructed ancestors exhibited similar structure topology as their descendants with the exception of a few loop deviations. Strikingly, molecular dynamics simulations revealed restricted conformational dynamics of ancestral enzymes, which prefer a single state, in contrast to modern enzymes adopting two different conformational states. The restricted dynamics can potentially be linked to their exceptional stabilization. The study provides molecular insights into protein stabilization due to ancestral sequence reconstruction, which is becoming a widely used approach for obtaining robust protein catalysts.
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Affiliation(s)
- Petra Babkova
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, Bld. A13, 625 00 Brno, Czech Republic
- International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
| | - Zuzana Dunajova
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, Bld. A13, 625 00 Brno, Czech Republic
| | - Radka Chaloupkova
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, Bld. A13, 625 00 Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, Bld. A13, 625 00 Brno, Czech Republic
- International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
| | - David Bednar
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, Bld. A13, 625 00 Brno, Czech Republic
- International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
| | - Martin Marek
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, Bld. A13, 625 00 Brno, Czech Republic
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9
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Gardner JM, Biler M, Risso VA, Sanchez-Ruiz JM, Kamerlin SCL. Manipulating Conformational Dynamics To Repurpose Ancient Proteins for Modern Catalytic Functions. ACS Catal 2020. [DOI: 10.1021/acscatal.0c00722] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jasmine M. Gardner
- Department of Chemistry - BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Michal Biler
- Department of Chemistry - BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Valeria A. Risso
- Departamento de Quı́mica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quı́mica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain
| | - Jose M. Sanchez-Ruiz
- Departamento de Quı́mica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quı́mica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain
| | - Shina C. L. Kamerlin
- Department of Chemistry - BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
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10
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Molecular origins of folding rate differences in the thioredoxin family. Biochem J 2020; 477:1083-1087. [DOI: 10.1042/bcj20190864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 12/13/2022]
Abstract
Thioredoxins are a family of conserved oxidoreductases responsible for maintaining redox balance within cells. They have also served as excellent model systems for protein design and engineering studies particularly through ancestral sequence reconstruction methods. The recent work by Gamiz-Arco et al. [Biochem J (2019) 476, 3631–3647] answers fundamental questions on how specific sequence differences can contribute to differences in folding rates between modern and ancient thioredoxins but also among a selected subset of modern thioredoxins. They surprisingly find that rapid unassisted folding, a feature of ancient thioredoxins, is not conserved in the modern descendants suggestive of co-evolution of better folding machinery that likely enabled the accumulation of mutations that slow-down folding. The work thus provides an interesting take on the expected folding-stability-function constraint while arguing for additional factors that contribute to sequence evolution and hence impact folding efficiency.
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11
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Campitelli P, Modi T, Kumar S, Ozkan SB. The Role of Conformational Dynamics and Allostery in Modulating Protein Evolution. Annu Rev Biophys 2020; 49:267-288. [PMID: 32075411 DOI: 10.1146/annurev-biophys-052118-115517] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Advances in sequencing techniques and statistical methods have made it possible not only to predict sequences of ancestral proteins but also to identify thousands of mutations in the human exome, some of which are disease associated. These developments have motivated numerous theories and raised many questions regarding the fundamental principles behind protein evolution, which have been traditionally investigated horizontally using the tip of the phylogenetic tree through comparative studies of extant proteins within a family. In this article, we review a vertical comparison of the modern and resurrected ancestral proteins. We focus mainly on the dynamical properties responsible for a protein's ability to adapt new functions in response to environmental changes. Using the Dynamic Flexibility Index and the Dynamic Coupling Index to quantify the relative flexibility and dynamic coupling at a site-specific, single-amino-acid level, we provide evidence that the migration of hinges, which are often functionally critical rigid sites, is a mechanism through which proteins can rapidly evolve. Additionally, we show that disease-associated mutations in proteins often result in flexibility changes even at positions distal from mutational sites, particularly in the modulation of active site dynamics.
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Affiliation(s)
- Paul Campitelli
- Center for Biological Physics, Department of Physics, Arizona State University, Tempe, Arizona 85281, USA; , ,
| | - Tushar Modi
- Center for Biological Physics, Department of Physics, Arizona State University, Tempe, Arizona 85281, USA; , ,
| | - Sudhir Kumar
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, Pennsylvania 19122, USA; .,Department of Biology, Temple University, Philadelphia, Pennsylvania 19122, USA.,Center for Excellence in Genome Medicine and Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - S Banu Ozkan
- Center for Biological Physics, Department of Physics, Arizona State University, Tempe, Arizona 85281, USA; , ,
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12
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Application of a protein domain as chaperone for enhancing biological activity and stability of other proteins. J Biotechnol 2020; 310:68-79. [DOI: 10.1016/j.jbiotec.2020.01.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/27/2020] [Accepted: 01/30/2020] [Indexed: 11/21/2022]
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13
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Napolitano S, Reber RJ, Rubini M, Glockshuber R. Functional analyses of ancestral thioredoxins provide insights into their evolutionary history. J Biol Chem 2019; 294:14105-14118. [PMID: 31366732 PMCID: PMC6755812 DOI: 10.1074/jbc.ra119.009718] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/29/2019] [Indexed: 12/24/2022] Open
Abstract
Thioredoxin (Trx) is a conserved, cytosolic reductase in all known organisms. The enzyme receives two electrons from NADPH via thioredoxin reductase (TrxR) and passes them on to multiple cellular reductases via disulfide exchange. Despite the ubiquity of thioredoxins in all taxa, little is known about the functions of resurrected ancestral thioredoxins in the context of a modern mesophilic organism. Here, we report on functional in vitro and in vivo analyses of seven resurrected Precambrian thioredoxins, dating back 1–4 billion years, in the Escherichia coli cytoplasm. Using synthetic gene constructs for recombinant expression of the ancestral enzymes, along with thermodynamic and kinetic assays, we show that all ancestral thioredoxins, as today's thioredoxins, exhibit strongly reducing redox potentials, suggesting that thioredoxins served as catalysts of cellular reduction reactions from the beginning of evolution, even before the oxygen catastrophe. A detailed, quantitative characterization of their interactions with the electron donor TrxR from Escherichia coli and the electron acceptor methionine sulfoxide reductase, also from E. coli, strongly hinted that thioredoxins and thioredoxin reductases co-evolved and that the promiscuity of thioredoxins toward downstream electron acceptors was maintained during evolution. In summary, our findings suggest that thioredoxins evolved high specificity for their sole electron donor TrxR while maintaining promiscuity to their multiple electron acceptors.
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Affiliation(s)
- Silvia Napolitano
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
| | - Robin J Reber
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
| | - Marina Rubini
- School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland
| | - Rudi Glockshuber
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
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14
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Han M, Liao S, Peng X, Zhou X, Chen Q, Liu H. Selection and analyses of variants of a designed protein suggest importance of hydrophobicity of partially buried sidechains for protein stability at high temperatures. Protein Sci 2019; 28:1437-1447. [PMID: 31074908 DOI: 10.1002/pro.3643] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/08/2019] [Accepted: 05/08/2019] [Indexed: 12/25/2022]
Abstract
Computationally designed proteins of high stability provide specimen in addition to natural proteins for the study of sequence-structure stability relationships at the very high end of protein stability spectrum. The melting temperature of E_1r26, a protein we previously designed using the A Backbone-based Amino aCid Usage Survey (ABACUS) sequence design program, is above 110 °C, more than 50 °C higher than that of the natural thioredoxin protein whose backbone (PDB ID 1R26) has been used as the design target. Using an experimental selection approach, we obtained variants of E_1r26 that remain folded but are of reduced stability, including one whose unfolding temperature and denaturing guanidine concentration are similar to those of 1r26. The mutant unfolds with a certain degree of cooperativity. Its structure solved by X-ray crystallography agrees with that of 1r26 by a root mean square deviation of 1.3 Å, adding supports to the accuracy of the ABACUS method. Analyses of intermediate mutants indicate that the substitution of two partially buried hydrophobic residues (isoleucine and leucine) by polar residues (threonine and serine, respectively) are responsible for the dramatic change in the unfolding temperature. It is suggested that the effects of mutations located in rigid secondary structure regions, but not those in loops, may be well predicted through ABACUS mutation energy analysis. The results also suggest that hydrophobic effects involving intermediately buried sidechains can be critically important for protein stability at high temperatures.
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Affiliation(s)
- Mingjie Han
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Sanhui Liao
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Xiong Peng
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Xiaoqun Zhou
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Quan Chen
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Haiyan Liu
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China.,School of Data Science, University of Science and Technology of China, Hefei, Anhui, China.,Hefei National Laboratory for Physical Sciences at the Microscale, Hefei, Anhui, China
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15
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Faber MS, Whitehead TA. Data-driven engineering of protein therapeutics. Curr Opin Biotechnol 2019; 60:104-110. [PMID: 30822697 DOI: 10.1016/j.copbio.2019.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/16/2018] [Accepted: 01/21/2019] [Indexed: 12/26/2022]
Abstract
Protein therapeutics requires a series of properties beyond biochemical activity, including serum stability, low immunogenicity, and manufacturability. Mutations that improve one property often decrease one or more of the other essential requirements for therapeutic efficacy, making the protein engineering challenge difficult. The past decade has seen an explosion of new techniques centered around cheaply reading and writing DNA. This review highlights the recent use of such high throughput technologies for engineering protein therapeutics. Examples include the use of human antibody repertoire sequence data to pair antibody heavy and light chains, comprehensive mutational analysis for engineering antibody specificity, and the use of ancestral and inter-species sequence data to engineer simultaneous improvements in enzyme catalytic efficiency and stability. We conclude with a perspective on further ways to integrate mature protein engineering pipelines with the exponential increases in the volume of sequencing data expected in the forthcoming decade.
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Affiliation(s)
- Matthew S Faber
- Dept. Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, United States
| | - Timothy A Whitehead
- Dept. of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824, United States; Dept. of Biosystems Engineering, Michigan State University, East Lansing, MI 48824, United States; Dept. of Biomedical Engineering, Michigan State University, East Lansing, MI 48824, United States; Institute for Quantitative Biology, Michigan State University, East Lansing, MI 48824, United States.
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16
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Trudeau DL, Tawfik DS. Protein engineers turned evolutionists-the quest for the optimal starting point. Curr Opin Biotechnol 2019; 60:46-52. [PMID: 30611116 DOI: 10.1016/j.copbio.2018.12.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 11/22/2018] [Accepted: 12/03/2018] [Indexed: 12/12/2022]
Abstract
The advent of laboratory directed evolution yielded a fruitful crosstalk between the disciplines of molecular evolution and bio-engineering. Here, we outline recent developments in both disciplines with respect to how one can identify the best starting points for directed evolution, such that highly efficient and robust tailor-made enzymes can be obtained with minimal optimization. Directed evolution studies have highlighted essential features of engineer-able enzymes: highly stable, mutationally robust enzymes with the capacity to accept a broad range of substrates. Robust, evolvable enzymes can be inferred from the natural sequence record. Broad substrate spectrum relates to conformational plasticity and can also be predicted by phylogenetic analyses and/or by computational design. Overall, an increasingly powerful toolkit is becoming available for identifying optimal starting points including network analyses of enzyme superfamilies and other bioinformatics methods.
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Affiliation(s)
- Devin L Trudeau
- Department of Biomolecular Sciences, Weizmann Institute of Science, 234 Herzl Street, Rehovot 7610001, Israel
| | - Dan S Tawfik
- Department of Biomolecular Sciences, Weizmann Institute of Science, 234 Herzl Street, Rehovot 7610001, Israel.
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17
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Straub K, Merkl R. Ancestral Sequence Reconstruction as a Tool for the Elucidation of a Stepwise Evolutionary Adaptation. Methods Mol Biol 2019; 1851:171-182. [PMID: 30298397 DOI: 10.1007/978-1-4939-8736-8_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Ancestral sequence reconstruction (ASR) is a powerful tool to infer primordial sequences from contemporary, i.e., extant ones. An essential element of ASR is the computation of a phylogenetic tree whose leaves are the chosen extant sequences. Most often, the reconstructed sequence related to the root of this tree is of greatest interest: It represents the common ancestor (CA) of the sequences under study. If this sequence encodes a protein, one can "resurrect" the CA by means of gene synthesis technology and study biochemical properties of this extinct predecessor with the help of wet-lab experiments.However, ASR deduces also sequences for all internal nodes of the tree, and the well-considered analysis of these "intermediates" can help to elucidate evolutionary processes. Moreover, one can identify key mutations that alter proteins or protein complexes and are responsible for the differing properties of extant proteins. As an illustrative example, we describe the protocol for the rapid identification of hotspots determining the binding of the two subunits within the heteromeric complex imidazole glycerol phosphate synthase.
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Affiliation(s)
- Kristina Straub
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Regensburg, Germany
| | - Rainer Merkl
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Regensburg, Germany.
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18
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Hendrikse NM, Charpentier G, Nordling E, Syrén PO. Ancestral diterpene cyclases show increased thermostability and substrate acceptance. FEBS J 2018; 285:4660-4673. [PMID: 30369053 DOI: 10.1111/febs.14686] [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: 06/04/2018] [Revised: 09/07/2018] [Accepted: 10/25/2018] [Indexed: 11/26/2022]
Abstract
Bacterial diterpene cyclases are receiving increasing attention in biocatalysis and synthetic biology for the sustainable generation of complex multicyclic building blocks. Herein, we explore the potential of ancestral sequence reconstruction (ASR) to generate remodeled cyclases with enhanced stability, activity, and promiscuity. Putative ancestors of spiroviolene synthase, a bacterial class I diterpene cyclase, display an increased yield of soluble protein of up to fourfold upon expression in the model organism Escherichia coli. Two of the resurrected enzymes, with an estimated age of approximately 1.7 million years, display an upward shift in thermostability of 7-13 °C. Ancestral spiroviolene synthases catalyze cyclization of the natural C20 -substrate geranylgeranyl diphosphate (GGPP) and also accept C15 farnesyl diphosphate (FPP), which is not converted by the extant enzyme. In contrast, the consensus sequence generated from the corresponding multiple sequence alignment was found to be inactive toward both substrates. Mutation of a nonconserved position within the aspartate-rich motif of the reconstructed ancestral cyclases was associated with modest effects on activity and relative substrate specificity (i.e., kcat /KM for GGPP over kcat /KM for FPP). Kinetic analyses performed at different temperatures reveal a loss of substrate saturation, when going from the ancestor with highest thermostability to the modern enzyme. The kinetics data also illustrate how an increase in temperature optimum of biocatalysis is reflected in altered entropy and enthalpy of activation. Our findings further highlight the potential and limitations of applying ASR to biosynthetic machineries in secondary metabolism.
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Affiliation(s)
- Natalie M Hendrikse
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden.,School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden.,Swedish Orphan Biovitrum AB, Stockholm, Sweden
| | - Gwenaëlle Charpentier
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | | | - Per-Olof Syrén
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden.,School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden.,Swedish Orphan Biovitrum AB, Stockholm, Sweden.,School of Engineering Sciences in Chemistry, Biotechnology and Health, Division of Protein Technology, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
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19
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Modi T, Huihui J, Ghosh K, Ozkan SB. Ancient thioredoxins evolved to modern-day stability-function requirement by altering native state ensemble. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170184. [PMID: 29735738 PMCID: PMC5941179 DOI: 10.1098/rstb.2017.0184] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/20/2018] [Indexed: 02/06/2023] Open
Abstract
Thioredoxins (THRXs)-small globular proteins that reduce other proteins-are ubiquitous in all forms of life, from Archaea to mammals. Although ancestral thioredoxins share sequential and structural similarity with the modern-day (extant) homologues, they exhibit significantly different functional activity and stability. We investigate this puzzle by comparative studies of their (ancient and modern-day THRXs') native state ensemble, as quantified by the dynamic flexibility index (DFI), a metric for the relative resilience of an amino acid to perturbations in the rest of the protein. Clustering proteins using DFI profiles strongly resemble an alternative classification scheme based on their activity and stability. The DFI profiles of the extant proteins are substantially different around the α3, α4 helices and catalytic regions. Likewise, allosteric coupling of the active site with the rest of the protein is different between ancient and extant THRXs, possibly explaining the decreased catalytic activity at low pH with evolution. At a global level, we note that the population of low-flexibility (called hinges) and high-flexibility sites increases with evolution. The heterogeneity (quantified by the variance) in DFI distribution increases with the decrease in the melting temperature typically associated with the evolution of ancient proteins to their modern-day counterparts.This article is part of a discussion meeting issue 'Allostery and molecular machines'.
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Affiliation(s)
- Tushar Modi
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, AZ 85281, USA
| | - Jonathan Huihui
- Department of Physics and Astronomy, University of Denver, Denver, CO 80209, USA
| | - Kingshuk Ghosh
- Department of Physics and Astronomy, University of Denver, Denver, CO 80209, USA
| | - S Banu Ozkan
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, AZ 85281, USA
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20
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Risso VA, Sanchez-Ruiz JM, Ozkan SB. Biotechnological and protein-engineering implications of ancestral protein resurrection. Curr Opin Struct Biol 2018; 51:106-115. [PMID: 29660672 DOI: 10.1016/j.sbi.2018.02.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 02/18/2018] [Accepted: 02/20/2018] [Indexed: 10/17/2022]
Abstract
Approximations to the sequences of ancestral proteins can be derived from the sequences of their modern descendants. Proteins encoded by such reconstructed sequences can be prepared in the laboratory and subjected to experimental scrutiny. These 'resurrected' ancestral proteins often display remarkable properties, reflecting ancestral adaptations to intra-cellular and extra-cellular environments that differed from the environments hosting modern/extant proteins. Recent experimental and computational work has specifically discussed high stability, substrate and catalytic promiscuity, conformational flexibility/diversity and altered patterns of interaction with other sub-cellular components. In this review, we discuss these remarkable properties as well as recent attempts to explore their biotechnological and protein-engineering potential.
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Affiliation(s)
- Valeria A Risso
- Departamento de Quimica Fisica, Facultad de Ciencias, University of Granada, 18071 Granada, Spain
| | - Jose M Sanchez-Ruiz
- Departamento de Quimica Fisica, Facultad de Ciencias, University of Granada, 18071 Granada, Spain.
| | - S Banu Ozkan
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, AZ 85281, United States.
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21
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Cortés Cabrera Á, Sánchez-Murcia PA, Gago F. Making sense of the past: hyperstability of ancestral thioredoxins explained by free energy simulations. Phys Chem Chem Phys 2018; 19:23239-23246. [PMID: 28825743 DOI: 10.1039/c7cp03659k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thioredoxin (Trx), a small and globular protein, is present in all kinds of organisms, from Archea to higher mammals. Throughout evolution, the Trx sequence has undergone subtle modifications to adapt to varying environmental conditions. The high degree of sequence conservation makes Trx very amenable to ancestral protein reconstruction techniques. In this work, we address the study of the structural and energetic determinants of thermostability in E. coli Trx using a dataset of mutations inspired by ancestral reconstruction. We compute, from first principles, the expected contribution of 19 different amino acid substitutions to the stability (ΔΔG) and the melting temperature (ΔTm) of the protein. We also describe the specific changes in structure and protein dynamics responsible for the stabilizing or destabilizing effects of these mutations. Our results point to local and independent changes for most of the variants. Our predictions are accurate enough to substantiate the proposal of new hypotheses regarding evolutionary relationships between mutations, as in the case of T89R, P68A and G74S or K90L and F102A, and reach beyond the initial set to suggest improved variants, such as K90I or K90Y.
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Affiliation(s)
- Álvaro Cortés Cabrera
- Área de Farmacología, Departamento de Ciencias Biomédicas, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain.
| | - Pedro A Sánchez-Murcia
- Área de Farmacología, Departamento de Ciencias Biomédicas, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain.
| | - Federico Gago
- Área de Farmacología, Departamento de Ciencias Biomédicas, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain.
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22
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Goldsmith M, Tawfik DS. Enzyme engineering: reaching the maximal catalytic efficiency peak. Curr Opin Struct Biol 2017; 47:140-150. [PMID: 29035814 DOI: 10.1016/j.sbi.2017.09.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 07/04/2017] [Accepted: 09/20/2017] [Indexed: 01/01/2023]
Abstract
The practical need for highly efficient enzymes presents new challenges in enzyme engineering, in particular, the need to improve catalytic turnover (kcat) or efficiency (kcat/KM) by several orders of magnitude. However, optimizing catalysis demands navigation through complex and rugged fitness landscapes, with optimization trajectories often leading to strong diminishing returns and dead-ends. When no further improvements are observed in library screens or selections, it remains unclear whether the maximal catalytic efficiency of the enzyme (the catalytic 'fitness peak') has been reached; or perhaps, an alternative combination of mutations exists that could yield additional improvements. Here, we discuss fundamental aspects of the process of catalytic optimization, and offer practical solutions with respect to overcoming optimization plateaus.
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Affiliation(s)
- Moshe Goldsmith
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
| | - Dan S Tawfik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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23
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Miller SR. An appraisal of the enzyme stability‐activity trade‐off. Evolution 2017; 71:1876-1887. [DOI: 10.1111/evo.13275] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 05/09/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Scott R. Miller
- Division of Biological SciencesThe University of Montana Missoula Montana 59812
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