1
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Petrovsky DV, Rudnev VR, Nikolsky KS, Kulikova LI, Malsagova KM, Kopylov AT, Kaysheva AL. PSSNet-An Accurate Super-Secondary Structure for Protein Segmentation. Int J Mol Sci 2022; 23:ijms232314813. [PMID: 36499138 PMCID: PMC9740782 DOI: 10.3390/ijms232314813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/18/2022] [Accepted: 11/24/2022] [Indexed: 12/03/2022] Open
Abstract
A super-secondary structure (SSS) is a spatially unique ensemble of secondary structural elements that determine the three-dimensional shape of a protein and its function, rendering SSSs attractive as folding cores. Understanding known types of SSSs is important for developing a deeper understanding of the mechanisms of protein folding. Here, we propose a universal PSSNet machine-learning method for SSS recognition and segmentation. For various types of SSS segmentation, this method uses key characteristics of SSS geometry, including the lengths of secondary structural elements and the distances between them, torsion angles, spatial positions of Cα atoms, and primary sequences. Using four types of SSSs (βαβ-unit, α-hairpin, β-hairpin, αα-corner), we showed that extensive SSS sets could be reliably selected from the Protein Data Bank and AlphaFold 2.0 database of protein structures.
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2
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3β-Corner Stability by Comparative Molecular Dynamics Simulations. Int J Mol Sci 2022; 23:ijms231911674. [PMID: 36232976 PMCID: PMC9570037 DOI: 10.3390/ijms231911674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 11/05/2022] Open
Abstract
This study explored the mechanisms by which the stability of super-secondary structures of the 3β-corner type autonomously outside the protein globule are maintained in an aqueous environment. A molecular dynamic (MD) study determined the behavioral diversity of a large set of non-homologous 3β-corner structures of various origins. We focused on geometric parameters such as change in gyration radius, solvent-accessible area, major conformer lifetime and torsion angles, and the number of hydrogen bonds. Ultimately, a set of 3β-corners from 330 structures was characterized by a root mean square deviation (RMSD) of less than 5 Å, a change in the gyration radius of no more than 5%, and the preservation of amino acid residues positioned within the allowed regions on the Ramachandran map. The studied structures retained their topologies throughout the MD experiments. Thus, the 3β-corner structure was found to be rather stable per se in a water environment, i.e., without the rest of a protein molecule, and can act as the nucleus or “ready-made” building block in protein folding. The 3β-corner can also be considered as an independent object for study in field of structural biology.
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3
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Decoding an Amino Acid Sequence to Extract Information on Protein Folding. Molecules 2022; 27:molecules27093020. [PMID: 35566370 PMCID: PMC9106047 DOI: 10.3390/molecules27093020] [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: 03/30/2022] [Revised: 05/01/2022] [Accepted: 05/05/2022] [Indexed: 01/27/2023] Open
Abstract
Protein folding is a complicated phenomenon including various time scales (μs to several s), and various structural indices are required to analyze it. The methodologies used to study this phenomenon also have a wide variety and employ various experimental and computational techniques. Thus, a simple speculation does not serve to understand the folding mechanism of a protein. In the present review, we discuss the recent studies conducted by the author and their colleagues to decode amino acid sequences to obtain information on protein folding. We investigate globin-like proteins, ferredoxin-like fold proteins, IgG-like beta-sandwich fold proteins, lysozyme-like fold proteins and β-trefoil-like fold proteins. Our techniques are based on statistics relating to the inter-residue average distance, and our studies performed so far indicate that the information obtained from these analyses includes data on the protein folding mechanism. The relationships between our results and the actual protein folding phenomena are also discussed.
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4
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Blaber M. Variable and Conserved Regions of Secondary Structure in the β-Trefoil Fold: Structure Versus Function. Front Mol Biosci 2022; 9:889943. [PMID: 35517858 PMCID: PMC9062101 DOI: 10.3389/fmolb.2022.889943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 04/01/2022] [Indexed: 11/13/2022] Open
Abstract
β-trefoil proteins exhibit an approximate C3 rotational symmetry. An analysis of the secondary structure for members of this diverse superfamily of proteins indicates that it is comprised of remarkably conserved β-strands and highly-divergent turn regions. A fundamental “minimal” architecture can be identified that is devoid of heterogenous and extended turn regions, and is conserved among all family members. Conversely, the different functional families of β-trefoils can potentially be identified by their unique turn patterns (or turn “signature”). Such analyses provide clues as to the evolution of the β-trefoil family, suggesting a folding/stability role for the β-strands and a functional role for turn regions. This viewpoint can also guide de novo protein design of β-trefoil proteins having novel functionality.
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Affiliation(s)
- Michael Blaber
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL, United States
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5
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Tenorio CA, Parker JB, Blaber M. Functionalization of a symmetric protein scaffold: Redundant folding nuclei and alternative oligomeric folding pathways. Protein Sci 2022; 31:e4301. [PMID: 35481645 PMCID: PMC8996475 DOI: 10.1002/pro.4301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 03/12/2022] [Accepted: 03/15/2022] [Indexed: 02/02/2023]
Abstract
Successful de novo protein design ideally targets specific folding kinetics, stability thermodynamics, and biochemical functionality, and the simultaneous achievement of all these criteria in a single step design is challenging. Protein design is potentially simplified by separating the problem into two steps: (a) an initial design of a protein "scaffold" having appropriate folding kinetics and stability thermodynamics, followed by (b) appropriate functional mutation-possibly involving insertion of a peptide functional "cassette." This stepwise approach can also separate the orthogonal effects of the "stability/function" and "foldability/function" tradeoffs commonly observed in protein design. If the scaffold is a protein architecture having an exact rotational symmetry, then there is the potential for redundant folding nuclei and multiple equivalent sites of functionalization; thereby enabling broader functional adaptation. We describe such a "scaffold" and functional "cassette" design strategy applied to a β-trefoil threefold symmetric architecture and a heparin ligand functionality. The results support the availability of redundant folding nuclei within this symmetric architecture, and also identify a minimal peptide cassette conferring heparin affinity. The results also identify an energy barrier of destabilization that switches the protein folding pathway from monomeric to trimeric, thereby identifying another potential advantage of symmetric protein architecture in de novo design.
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Affiliation(s)
- Connie A. Tenorio
- Department of Biomedical SciencesFlorida State UniversityTallahasseeFloridaUSA
| | - Joseph B. Parker
- Department of Biomedical SciencesFlorida State UniversityTallahasseeFloridaUSA
| | - Michael Blaber
- Department of Biomedical SciencesFlorida State UniversityTallahasseeFloridaUSA
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6
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Alvarez-Carreño C, Penev PI, Petrov AS, Williams LD. Fold Evolution before LUCA: Common Ancestry of SH3 Domains and OB Domains. Mol Biol Evol 2021; 38:5134-5143. [PMID: 34383917 PMCID: PMC8557408 DOI: 10.1093/molbev/msab240] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
SH3 and OB are the simplest, oldest, and most common protein domains within the translation system. SH3 and OB domains are β-barrels that are structurally similar but are topologically distinct. To transform an OB domain to a SH3 domain, β-strands must be permuted in a multistep and evolutionarily implausible mechanism. Here, we explored relationships between SH3 and OB domains of ribosomal proteins, initiation, and elongation factors using a combined sequence- and structure-based approach. We detect a common core of SH3 and OB domains, as a region of significant structure and sequence similarity. The common core contains four β-strands and a loop, but omits the fifth β-strand, which is variable and is absent from some OB and SH3 domain proteins. The structure of the common core immediately suggests a simple permutation mechanism for interconversion between SH3 and OB domains, which appear to share an ancestor. The OB domain was formed by duplication and adaptation of the SH3 domain core, or vice versa, in a simple and probable transformation. By employing the folding algorithm AlphaFold2, we demonstrated that an ancestral reconstruction of a permuted SH3 sequence folds into an OB structure, and an ancestral reconstruction of a permuted OB sequence folds into a SH3 structure. The tandem SH3 and OB domains in the universal ribosomal protein uL2 share a common ancestor, suggesting that the divergence of these two domains occurred before the last universal common ancestor.
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Affiliation(s)
- Claudia Alvarez-Carreño
- NASA Center for the Origin of Life, Georgia Institute of Technology, Atlanta, GA, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA
| | - Petar I Penev
- NASA Center for the Origin of Life, Georgia Institute of Technology, Atlanta, GA, USA
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Anton S Petrov
- NASA Center for the Origin of Life, Georgia Institute of Technology, Atlanta, GA, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA
| | - Loren Dean Williams
- NASA Center for the Origin of Life, Georgia Institute of Technology, Atlanta, GA, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA
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7
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Parker JB, Tenorio CA, Blaber M. The ubiquitous buried water in the beta-trefoil architecture contributes to the folding nucleus and ~20% of the folding enthalpy. Protein Sci 2021; 30:2287-2297. [PMID: 34562298 DOI: 10.1002/pro.4192] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 01/17/2023]
Abstract
The beta-trefoil protein architecture is characterized by three repeating "trefoil" motifs related by rotational symmetry and postulated to have evolved via gene duplication and fusion events. Despite this apparent structural symmetry, the primary and secondary structural elements typically exhibit pronounced asymmetric features. A survey of this family of proteins has revealed that among the most conserved symmetric structural elements is a ubiquitous buried solvent which participates in a bridging H-bond with three different beta-strands in each of the trefoil motifs. A computational analysis reported that these waters are likely associated with a substantial enthalpic contribution to overall stability. In this report, a Pro mutation is used to disrupt one of the water H-bond interactions to a main chain amide, and the effects upon stability and folding kinetics are determined. Combined with Ala mutations, the separate effects upon side chain truncation and H-bond deletion are analyzed in terms of stability and folding kinetics. The results show that these buried waters act to assemble a central folding nucleus, and are responsible for ~20% of the overall favorable enthalpy of folding.
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Affiliation(s)
- Joseph B Parker
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Connie A Tenorio
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Michael Blaber
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
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8
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Blaber M. Cooperative hydrophobic core interactions in the β-trefoil architecture. Protein Sci 2021; 30:956-965. [PMID: 33686691 DOI: 10.1002/pro.4059] [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: 02/08/2021] [Revised: 03/05/2021] [Accepted: 03/05/2021] [Indexed: 11/09/2022]
Abstract
Symmetric protein architectures have a compelling aesthetic that suggests a plausible evolutionary process (i.e., gene duplication/fusion) yielding complex architecture from a simpler structural motif. Furthermore, symmetry inspires a practical approach to computational protein design that substantially reduces the combinatorial explosion problem, and may provide practical solutions for structure optimization. Despite such broad relevance, the role of structural symmetry in the key area of hydrophobic core-packing cooperativity has not been adequately studied. In the present report, the threefold rotational symmetry intrinsic to the β-trefoil architecture is shown to form a geometric basis for highly-cooperative core-packing interactions that both stabilize the local repeating motif and promote oligomerization/long-range contacts in the folding process. Symmetry in the β-trefoil structure also permits tolerance towards mutational drift that involves a structural quasi-equivalence at several key core positions.
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Affiliation(s)
- Michael Blaber
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
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9
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Mylemans B, Noguchi H, Deridder E, Lescrinier E, Tame JRH, Voet ARD. Influence of circular permutations on the structure and stability of a six-fold circular symmetric designer protein. Protein Sci 2020; 29:2375-2386. [PMID: 33006397 DOI: 10.1002/pro.3961] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/23/2020] [Accepted: 09/26/2020] [Indexed: 11/09/2022]
Abstract
The β-propeller fold is adopted by a sequentially diverse family of repeat proteins with apparent rotational symmetry. While the structure is mostly stabilized by hydrophobic interactions, an additional stabilization is provided by hydrogen bonds between the N-and C-termini, which are almost invariably part of the same β-sheet. This feature is often referred to as the "Velcro" closure. The positioning of the termini within a blade is variable and depends on the protein family. In order to investigate the influence of this location on protein structure, folding and stability, we created different circular permutants, and a circularized version, of the designer propeller protein named Pizza. This protein is perfectly symmetrical, possessing six identical repeats. While all mutants adopt the same structure, the proteins lacking the "Velcro" closure were found to be significantly less resistant to thermal and chemical denaturation. This could explain why such proteins are rarely observed in nature. Interestingly the most common "Velcro" configuration for this protein family was not the most stable among the Pizza variants tested. The circularized version shows dramatically improved stability, which could have implications for future applications.
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Affiliation(s)
| | | | - Els Deridder
- Department of Chemistry, KU Leuven, Leuven, Belgium
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10
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Tenorio CA, Parker JB, Blaber M. Oligomerization of a symmetric β-trefoil protein in response to folding nucleus perturbation. Protein Sci 2020; 29:1629-1640. [PMID: 32362013 DOI: 10.1002/pro.3877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/24/2020] [Accepted: 04/28/2020] [Indexed: 11/06/2022]
Abstract
Gene duplication and fusion events in protein evolution are postulated to be responsible for the common protein folds exhibiting internal rotational symmetry. Such evolutionary processes can also potentially yield regions of repetitive primary structure. Repetitive primary structure offers the potential for alternative definitions of critical regions, such as the folding nucleus (FN). In principle, more than one instance of the FN potentially enables an alternative folding pathway in the face of a subsequent deleterious mutation. We describe the targeted mutation of the carboxyl-terminal region of the (internally located) FN of the de novo designed purely-symmetric β-trefoil protein Symfoil-4P. This mutation involves wholesale replacement of a repeating trefoil-fold motif with a "blade" motif from a β-propeller protein, and postulated to trap that region of the Symfoil-4P FN in a nonproductive folding intermediate. The resulting protein (termed "Bladefoil") is shown to be cooperatively folding, but as a trimeric oligomer. The results illustrate how symmetric protein architectures have potentially diverse folding alternatives available to them, including oligomerization, when preferred pathways are perturbed.
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Affiliation(s)
- Connie A Tenorio
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Joseph B Parker
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Michael Blaber
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
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11
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Tenorio CA, Longo LM, Parker JB, Lee J, Blaber M. Ab initio folding of a trefoil-fold motif reveals structural similarity with a β-propeller blade motif. Protein Sci 2020; 29:1172-1185. [PMID: 32142181 DOI: 10.1002/pro.3850] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 03/01/2020] [Accepted: 03/03/2020] [Indexed: 01/05/2023]
Abstract
Many protein architectures exhibit evidence of internal rotational symmetry postulated to be the result of gene duplication/fusion events involving a primordial polypeptide motif. A common feature of such structures is a domain-swapped arrangement at the interface of the N- and C-termini motifs and postulated to provide cooperative interactions that promote folding and stability. De novo designed symmetric protein architectures have demonstrated an ability to accommodate circular permutation of the N- and C-termini in the overall architecture; however, the folding requirement of the primordial motif is poorly understood, and tolerance to circular permutation is essentially unknown. The β-trefoil protein fold is a threefold-symmetric architecture where the repeating ~42-mer "trefoil-fold" motif assembles via a domain-swapped arrangement. The trefoil-fold structure in isolation exposes considerable hydrophobic area that is otherwise buried in the intact β-trefoil trimeric assembly. The trefoil-fold sequence is not predicted to adopt the trefoil-fold architecture in ab initio folding studies; rather, the predicted fold is closely related to a compact "blade" motif from the β-propeller architecture. Expression of a trefoil-fold sequence and circular permutants shows that only the wild-type N-terminal motif definition yields an intact β-trefoil trimeric assembly, while permutants yield monomers. The results elucidate the folding requirements of the primordial trefoil-fold motif, and also suggest that this motif may sample a compact conformation that limits hydrophobic residue exposure, contains key trefoil-fold structural features, but is more structurally homologous to a β-propeller blade motif.
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Affiliation(s)
- Connie A Tenorio
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Liam M Longo
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Joseph B Parker
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
| | - Jihun Lee
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, USA
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12
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Noguchi H, Addy C, Simoncini D, Wouters S, Mylemans B, Van Meervelt L, Schiex T, Zhang KYJ, Tame JRH, Voet ARD. Computational design of symmetrical eight-bladed β-propeller proteins. IUCRJ 2019; 6:46-55. [PMID: 30713702 PMCID: PMC6327176 DOI: 10.1107/s205225251801480x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/19/2018] [Indexed: 05/04/2023]
Abstract
β-Propeller proteins form one of the largest families of protein structures, with a pseudo-symmetrical fold made up of subdomains called blades. They are not only abundant but are also involved in a wide variety of cellular processes, often by acting as a platform for the assembly of protein complexes. WD40 proteins are a subfamily of propeller proteins with no intrinsic enzymatic activity, but their stable, modular architecture and versatile surface have allowed evolution to adapt them to many vital roles. By computationally reverse-engineering the duplication, fusion and diversification events in the evolutionary history of a WD40 protein, a perfectly symmetrical homologue called Tako8 was made. If two or four blades of Tako8 are expressed as single polypeptides, they do not self-assemble to complete the eight-bladed architecture, which may be owing to the closely spaced negative charges inside the ring. A different computational approach was employed to redesign Tako8 to create Ika8, a fourfold-symmetrical protein in which neighbouring blades carry compensating charges. Ika2 and Ika4, carrying two or four blades per subunit, respectively, were found to assemble spontaneously into a complete eight-bladed ring in solution. These artificial eight-bladed rings may find applications in bionanotechnology and as models to study the folding and evolution of WD40 proteins.
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Affiliation(s)
- Hiroki Noguchi
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Leuven, Belgium
| | - Christine Addy
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa 230-0045, Japan
| | - David Simoncini
- MIAT, Université de Toulouse, INRA, Castanet-Tolosan, France
| | - Staf Wouters
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Leuven, Belgium
| | - Bram Mylemans
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Leuven, Belgium
| | - Luc Van Meervelt
- Laboratory of Biomolecular Architecture, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Thomas Schiex
- MIAT, Université de Toulouse, INRA, Castanet-Tolosan, France
| | - Kam Y. J. Zhang
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Yokohama, Kanagawa 230-0045, Japan
| | - Jeremy R. H. Tame
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa 230-0045, Japan
| | - Arnout R. D. Voet
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Leuven, Belgium
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13
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Angalakurthi SK, Tenorio CA, Blaber M, Middaugh CR. Investigating the dynamics and polyanion binding sites of fibroblast growth factor-1 using hydrogen-deuterium exchange mass spectrometry. Protein Sci 2018; 27:1068-1082. [PMID: 29645318 DOI: 10.1002/pro.3423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 01/12/2023]
Abstract
In this study, we examined the local dynamics of acidic fibroblast growth factor (FGF-1) as well as the binding sites of various polyanions including poly-sulfates (heparin and low MW heparin) and poly-phosphates (phytic acid and ATP) using hydrogen-deuterium exchange mass spectrometry (HX-MS). For local dynamics, results are analyzed at the peptide level as well as in terms of buried amides employing crystallographic B-factors and compared with a residue level heat map generated from HX-MS results. Results show that strand 4 and 5 and the turn between them to be the most flexible regions as was previously seen by NMR. On the other hand, the C-terminal strands 8, 9, and 10 appear to be more rigid which is also consistent with crystallographic B-factors as well as local dynamics studies conducted by NMR. Crystal structures of FGF-1 in complex with heparin have shown that heparin binds to N-terminal Asn18 and to C-terminal Lys105, Tryp107, Lys112, Lys113, Arg119, Pro121, Arg122, Gln127, and Lys128 indicating electrostatic forces as dominant interactions. Heparin binding as determined by HX-MS is consistent with crystallography data. Previous studies have also shown that other polyanions including low MW heparin, phytic acid and ATP dramatically increase the thermal stability of FGF-1. Using HX-MS, we find other poly anions tested bind in a similar manner to heparin, primarily targeting the turns in the lysine rich C-terminal region of FGF-1 along with two distinct N-terminal regions that contains lysines and arginines/histidines. This confirms the interactions between FGF-1 and polyanions are primary directed by electrostatics.
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Affiliation(s)
- Siva K Angalakurthi
- Department of Pharmaceutical chemistry, University of Kansas, Lawrence, KS, 66047
| | - Connie A Tenorio
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306-4300
| | - Michael Blaber
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL, 32306-4300.,Program in Molecular Biophysics, Florida State University, Tallahassee, FL, 32306-4380
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14
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Noguchi H, Mylemans B, De Zitter E, Van Meervelt L, Tame JRH, Voet A. Design of tryptophan-containing mutants of the symmetrical Pizza protein for biophysical studies. Biochem Biophys Res Commun 2018; 497:1038-1042. [PMID: 29481797 DOI: 10.1016/j.bbrc.2018.02.168] [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: 02/19/2018] [Accepted: 02/22/2018] [Indexed: 01/29/2023]
Abstract
β-propeller proteins are highly symmetrical, being composed of a repeated motif with four anti-parallel β-sheets arranged around a central axis. Recently we designed the first completely symmetrical β-propeller protein, Pizza6, consisting of six identical tandem repeats. Pizza6 is expected to prove a useful building block for bionanotechnology, and also a tool to investigate the folding and evolution of β-propeller proteins. Folding studies are made difficult by the high stability and the lack of buried Trp residues to act as monitor fluorophores, so we have designed and characterized several Trp-containing Pizza6 derivatives. In total four proteins were designed, of which three could be purified and characterized. Crystal structures confirm these mutant proteins maintain the expected structure, and a clear redshift of Trp fluorescence emission could be observed upon denaturation. Among the derivative proteins, Pizza6-AYW appears to be the most suitable model protein for future folding/unfolding kinetics studies as it has a comparable stability as natural β-propeller proteins.
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Affiliation(s)
- Hiroki Noguchi
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, University of Leuven, Celestijnenlaan 200G-bus2403, Heverlee, Belgium
| | - Bram Mylemans
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, University of Leuven, Celestijnenlaan 200G-bus2403, Heverlee, Belgium
| | - Elke De Zitter
- Laboratory of Biomolecular Architecture, Department of Chemistry, University of Leuven, Celestijnenlaan 200F-bus2404, Heverlee, Belgium
| | - Luc Van Meervelt
- Laboratory of Biomolecular Architecture, Department of Chemistry, University of Leuven, Celestijnenlaan 200F-bus2404, Heverlee, Belgium
| | - Jeremy R H Tame
- Drug Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa, 230-0045, Japan
| | - Arnout Voet
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, University of Leuven, Celestijnenlaan 200G-bus2403, Heverlee, Belgium.
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15
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Terada D, Voet ARD, Noguchi H, Kamata K, Ohki M, Addy C, Fujii Y, Yamamoto D, Ozeki Y, Tame JRH, Zhang KYJ. Computational design of a symmetrical β-trefoil lectin with cancer cell binding activity. Sci Rep 2017; 7:5943. [PMID: 28724971 PMCID: PMC5517649 DOI: 10.1038/s41598-017-06332-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/12/2017] [Indexed: 01/24/2023] Open
Abstract
Computational protein design has advanced very rapidly over the last decade, but there remain few examples of artificial proteins with direct medical applications. This study describes a new artificial β-trefoil lectin that recognises Burkitt’s lymphoma cells, and which was designed with the intention of finding a basis for novel cancer treatments or diagnostics. The new protein, called “Mitsuba”, is based on the structure of the natural shellfish lectin MytiLec-1, a member of a small lectin family that uses unique sequence motifs to bind α-D-galactose. The three subdomains of MytiLec-1 each carry one galactose binding site, and the 149-residue protein forms a tight dimer in solution. Mitsuba (meaning “three-leaf” in Japanese) was created by symmetry constraining the structure of a MytiLec-1 subunit, resulting in a 150-residue sequence that contains three identical tandem repeats. Mitsuba-1 was expressed and crystallised to confirm the X-ray structure matches the predicted model. Mitsuba-1 recognises cancer cells that express globotriose (Galα(1,4)Galβ(1,4)Glc) on the surface, but the cytotoxicity is abolished.
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Affiliation(s)
- Daiki Terada
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa, 230-0045, Japan.,Structural Bioinformatics Team, Division of Structural and Synthetic Biology, Center for Life Science Technologies, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan
| | - Arnout R D Voet
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001, Heverlee, Belgium
| | - Hiroki Noguchi
- Laboratory of Biomolecular Modelling and Design, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001, Heverlee, Belgium
| | - Kenichi Kamata
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa, 230-0045, Japan
| | - Mio Ohki
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa, 230-0045, Japan
| | - Christine Addy
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa, 230-0045, Japan
| | - Yuki Fujii
- Department of Pharmacy, Graduate School of Pharmaceutical Science, Nagasaki International University, 2825-7 Huis Ten Bosch, Sasebo, Nagasaki, 859-3298, Japan
| | - Daiki Yamamoto
- Laboratory of Glycobiology and Marine Biochemistry, Graduate School of NanoBio Sciences, Yokohama City University, 22-2, Seto, Yokohama, Kanagawa, 236-0027, Japan
| | - Yasuhiro Ozeki
- Laboratory of Glycobiology and Marine Biochemistry, Graduate School of NanoBio Sciences, Yokohama City University, 22-2, Seto, Yokohama, Kanagawa, 236-0027, Japan
| | - Jeremy R H Tame
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa, 230-0045, Japan.
| | - Kam Y J Zhang
- Structural Bioinformatics Team, Division of Structural and Synthetic Biology, Center for Life Science Technologies, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan.
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Crystal structure of MytiLec, a galactose-binding lectin from the mussel Mytilus galloprovincialis with cytotoxicity against certain cancer cell types. Sci Rep 2016; 6:28344. [PMID: 27321048 PMCID: PMC4913266 DOI: 10.1038/srep28344] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/31/2016] [Indexed: 01/07/2023] Open
Abstract
MytiLec is a lectin, isolated from bivalves, with cytotoxic activity against cancer cell lines that express globotriaosyl ceramide, Galα(1,4)Galβ(1,4)Glcα1-Cer, on the cell surface. Functional analysis shows that the protein binds to the disaccharide melibiose, Galα(1,6)Glc, and the trisaccharide globotriose, Galα(1,4)Galβ(1,4)Glc. Recombinant MytiLec expressed in bacteria showed the same haemagglutinating and cytotoxic activity against Burkitt's lymphoma (Raji) cells as the native form. The crystal structure has been determined to atomic resolution, in the presence and absence of ligands, showing the protein to be a member of the β-trefoil family, but with a mode of ligand binding unique to a small group of related trefoil lectins. Each of the three pseudo-equivalent binding sites within the monomer shows ligand binding, and the protein forms a tight dimer in solution. An engineered monomer mutant lost all cytotoxic activity against Raji cells, but retained some haemagglutination activity, showing that the quaternary structure of the protein is important for its cellular effects.
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