1
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Xu LL, Gasset M, Lin H, Yu C, Zhao JL, Dang XW, Li ZX. Identification of the Dominant T-Cell Epitopes of Lit v 1 Shrimp Major Allergen and Their Functional Overlap with Known B-Cell Epitopes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:7420-7428. [PMID: 34170668 DOI: 10.1021/acs.jafc.1c02231] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Development of efficient peptide-based immunotherapy for shrimp allergy relies on the identification of the dominant T-cell epitopes of its major allergen, tropomyosin. In this study, immunoinformatic tools, T-cell proliferation, cytokine release, IgG/IgE binding, and degranulation assays were used to identify and characterize the T-cell epitopes in Lit v 1 in comparison with previously validated B-cell epitopes. The results showed that of the six in silico predicted T-cell epitopes only one (T2: VQESLLKANIQLVEK, 60-74) promoted T-cell proliferation, the release of IL-2, and upregulated secretion of Th2-associated cytokines in the absence of IgG/IgE binding and degranulation activities. These findings support T2 as a candidate for the development of an efficient peptide-based vaccine for the immunotherapy for shrimp-allergic patients.
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Affiliation(s)
- Li Li Xu
- College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China
| | - María Gasset
- Institute of Physical Chemistry Rocasolano (IQFR), Spanish National Research Council (CSIC), 28006 Madrid, Spain
| | - Hong Lin
- College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China
| | - Chuang Yu
- College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China
| | - Jin Long Zhao
- College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China
| | - Xue Wen Dang
- College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China
| | - Zhen Xing Li
- College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China
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2
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Day K, Schneible JD, Young AT, Pozdin VA, Van Den Driessche G, Gaffney LA, Prodromou R, Freytes DO, Fourches D, Daniele M, Menegatti S. Photoinduced reconfiguration to control the protein-binding affinity of azobenzene-cyclized peptides. J Mater Chem B 2021; 8:7413-7427. [PMID: 32661544 DOI: 10.1039/d0tb01189d] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The impact of next-generation biorecognition elements (ligands) will be determined by the ability to remotely control their binding activity for a target biomolecule in complex environments. Compared to conventional mechanisms for regulating binding affinity (pH, ionic strength, or chaotropic agents), light provides higher accuracy and rapidity, and is particularly suited for labile targets. In this study, we demonstrate a general method to develop azobenzene-cyclized peptide ligands with light-controlled affinity for target proteins. Light triggers a cis/trans isomerization of the azobenzene, which results in a major structural rearrangement of the cyclic peptide from a non-binding to a binding configuration. Critical to this goal are the ability to achieve efficient photo-isomerization under low light dosage and the temporal stability of both cis and trans isomers. We demonstrated our method by designing photo-switchable peptides targeting vascular cell adhesion marker 1 (VCAM1), a cell marker implicated in stem cell function. Starting from a known VCAM1-binding linear peptide, an ensemble of azobenzene-cyclized variants with selective light-controlled binding were identified by combining in silico design with experimental characterization via spectroscopy and surface plasmon resonance. Variant cycloAZOB[G-VHAKQHRN-K] featured rapid, light-controlled binding of VCAM1 (KD,trans/KD,cis ∼ 130). Biotin-cycloAZOB[G-VHAKQHRN-K] was utilized to label brain microvascular endothelial cells (BMECs), showing co-localization with anti-VCAM1 antibodies in cis configuration and negligible binding in trans configuration.
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Affiliation(s)
- Kevin Day
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina, USA.
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3
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Barnes BE, Jenkins TA, Stein LM, Mathers RT, Wicaksana M, Pasquinelli MA, Savin DA. Synthesis and Characterization of a Leucine-Based Block Co-Polypeptide: The Effect of the Leucine Zipper on Self-Assembly. Biomacromolecules 2020; 21:2463-2472. [PMID: 32378896 DOI: 10.1021/acs.biomac.0c00420] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The self-assembly behavior of an ABC triblock copolypeptide consisting of poly(ethylene oxide-b-(leucine-s-valine)-b-lysine) (PEO-PLV-PK) was examined via dynamic light scattering in dilute aqueous solution. Leucine is a hydrophobic, α-helix forming polypeptide that exhibits a "zipper effect" in coiled-coil dimers. We hypothesize that the specific interaction afforded by the leucine zipper dominates the thermodynamics of self-assembly through the side-by-side ordering of α-helices, which drives vesicle formation in a polymer with only 6 wt % hydrophobic content. Additionally, a multitude of assembly sizes and morphologies were attainable from a single polymer, depending on the solution processing method. Thermodynamic effects of the leucine zipper can be interpreted, in part, from solubility parameters determined from molecular modeling. The combination of synthesis, solvent processing, and computational studies helps to elucidate the thermodynamic effects of this unique assembly motif on classical self-assembly processes.
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Affiliation(s)
- Brooke E Barnes
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Taylor A Jenkins
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Lauren M Stein
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Robert T Mathers
- Department of Chemistry, The Pennsylvania State University, New Kensington, Pennsylvania 15068, United States
| | - Masita Wicaksana
- William G. Enloe Magnet High School, 128 Clarendon Crescent, Raleigh, North Carolina 27610, United States
| | - Melissa A Pasquinelli
- Fiber and Polymer Science Program, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Daniel A Savin
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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4
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Vertical Alignment of Size-Controlled Self-Assembled Diphenylalanine Peptide Nanotubes Using Polyethersulfone Hollow Fiber Membranes On Silicon. Int J Pept Res Ther 2019. [DOI: 10.1007/s10989-018-9725-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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5
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Haider MJ, Zhang HV, Sinha N, Fagan JA, Kiick KL, Saven JG, Pochan DJ. Self-assembly and soluble aggregate behavior of computationally designed coiled-coil peptide bundles. SOFT MATTER 2018; 14:5488-5496. [PMID: 29923575 PMCID: PMC6355460 DOI: 10.1039/c8sm00435h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Coiled-coil peptides have proven useful in a range of materials applications ranging from the formation of well-defined fibrils to responsive hydrogels. The ability to design from first principles their oligomerization and subsequent higher order assembly offers their expanded use in producing new materials. Toward these ends, homo-tetrameric, antiparallel, coiled-coil, peptide bundles have been designed computationally, synthesized via solid-phase methods, and their solution behavior characterized. Two different bundle-forming peptides were designed and examined. Within the targeted coiled coil structure, both bundles contained the same hydrophobic core residues. However, different exterior residues on the two different designs yielded sequences with different distributions of charged residues and two different expected isoelectric points of pI 4.4 and pI 10.5. Both coiled-coil bundles were extremely stable with respect to temperature (Tm > 80 C) and remained soluble in solution even at high (millimolar) peptide concentrations. The coiled-coil tetramer was confirmed to be the dominant species in solution by analytical sedimentation studies and by small-angle neutron scattering, where the scattering form factor is well represented by a cylinder model with the dimensions of the targeted coiled coil. At high concentrations (5-15 mM), evidence of interbundle structure was observed via neutron scattering. At these concentrations, the synthetic bundles form soluble aggregates, and interbundle distances can be determined via a structure factor fit to scattering data. The data support the successful design of robust coiled-coil bundles. Despite their different sequences, each sequence forms loosely associated but soluble aggregates of the bundles, suggesting similar dissociated states for each. The behavior of the dispersed bundles is similar to that observed for natural proteins.
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Affiliation(s)
- Michael J. Haider
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA. ,
| | - Huixi Violet Zhang
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - Nairiti Sinha
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA. ,
| | - Jeffrey A. Fagan
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
| | - Kristi L. Kiick
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA. ,
| | - Jeffery G. Saven
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - Darrin J. Pochan
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA. ,
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6
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Siriwardane DA, Kulikov O, Rokhlenko Y, Perananthan S, Novak BM. Stereocomplexation of Helical Polycarbodiimides Synthesized from Achiral Monomers Bearing Isopropyl Pendants. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01633] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Dumindika A. Siriwardane
- Department
of Chemistry and Biochemistry, University of Texas Dallas, Richardson, Texas 75080, United States
| | - Oleg Kulikov
- Department
of Chemistry and Biochemistry, University of Texas Dallas, Richardson, Texas 75080, United States
| | - Yekaterina Rokhlenko
- Department
of Chemical and Environmental Engineering, Yale University, 9f
Hillhouse Avenue, New Haven, Connecticut 06511, United States
| | - Sahila Perananthan
- Department
of Chemistry and Biochemistry, University of Texas Dallas, Richardson, Texas 75080, United States
| | - Bruce M. Novak
- Department
of Chemistry and Biochemistry, University of Texas Dallas, Richardson, Texas 75080, United States
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7
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Park J, Kim MS, Joo K, Lee J, Shin DH. An artificially constructed dimer through deformation of a short zinc-binding loop. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1866:205-213. [PMID: 29122686 DOI: 10.1016/j.bbapap.2017.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 10/24/2017] [Accepted: 11/01/2017] [Indexed: 10/18/2022]
Abstract
We have analyzed the crystal structure of the dimeric form of d-glycero-d-manno-heptose-1,7-bisphosphate phosphatase from Burkholderia thailandensis (BtGmhB), catalyzing the removal of the phosphate at the 7 position of d-glycero-d-manno-heptose-1,7-bisphosphate. The crystal structure of BtGmhB revealed a dimeric form caused by a disruption of a short zinc-binding loop. The dimeric BtGmhB structure was induced by triggering the loss of Zn2+via the protonation of cysteine residues at pH 4.8 of the crystallization condition. Similarly, the addition of EDTA also causes the dimerization of BtGmhB. It appears there are two dimeric forms in solution with and without the disulfide bridge mediated by Cys95. The disulfide-free dimer produced by the loss of Zn2+ in the short zinc-binding loop is further converted to a stable disulfide-bonded dimer in vitro. Though the two dimeric forms are reversible, both of them are inactive due to a deformation of the active site. Single and triple mutant experiments confirmed the presence of two dimeric forms in vitro. Phosphatase assay results showed that only a zinc-bound monomeric form contains catalytic activity in contrast to the inactive zinc-free dimeric forms. The monomer-to-dimer transition caused by the loss of Zn2+ observed in this study is an example of reversal phenomenon caused by artificial proteins containing protein engineered zinc-finger motifs where the monomer-to-dimer transitions occurred in the presence of Zn2+. Therefore, this unusual dimerization process may be applicable to designing proteins possessing a short zinc-binding loop with a novel regulatory role.
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Affiliation(s)
- Jimin Park
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Global Top5 Research Program, Ewha W. University, Seoul 03760, Republic of Korea
| | - Mi-Sun Kim
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Global Top5 Research Program, Ewha W. University, Seoul 03760, Republic of Korea
| | - Keehyoung Joo
- Center for in silico Protein Science, School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-722, Republic of Korea
| | - Jooyoung Lee
- Center for in silico Protein Science, School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-722, Republic of Korea.
| | - Dong Hae Shin
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Global Top5 Research Program, Ewha W. University, Seoul 03760, Republic of Korea.
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8
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Duim H, Otto S. Towards open-ended evolution in self-replicating molecular systems. Beilstein J Org Chem 2017; 13:1189-1203. [PMID: 28694865 PMCID: PMC5496545 DOI: 10.3762/bjoc.13.118] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 05/18/2017] [Indexed: 01/24/2023] Open
Abstract
In this review we discuss systems of self-replicating molecules in the context of the origin of life and the synthesis of de novo life. One of the important aspects of life is the ability to reproduce and evolve continuously. In this review we consider some of the prerequisites for obtaining unbounded evolution of self-replicating molecules and describe some recent advances in this field. While evolution experiments involving self-replicating molecules have shown promising results, true open-ended evolution has not been realized so far. A full understanding of the requirements for open-ended evolution would provide a better understanding of how life could have emerged from molecular building blocks and what is needed to create a minimal form of life in the laboratory.
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Affiliation(s)
- Herman Duim
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Sijbren Otto
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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9
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Abstract
α-Helical coiled coils constitute one of the most diverse folds yet described. They range in length over two orders of magnitude; they form rods, segmented ropes, barrels, funnels, sheets, spirals, and rings, which encompass anywhere from two to more than 20 helices in parallel or antiparallel orientation; they assume different helix crossing angles, degrees of supercoiling, and packing geometries. This structural diversity supports a wide range of biological functions, allowing them to form mechanically rigid structures, provide levers for molecular motors, project domains across large distances, mediate oligomerization, transduce conformational changes and facilitate the transport of other molecules. Unlike almost any other protein fold known to us, their structure can be computed from parametric equations, making them an ideal model system for rational protein design. Here we outline the principles by which coiled coils are structured, review the determinants of their folding and stability, and present an overview of their diverse architectures.
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10
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Swainsbury DJK, Harniman RL, Di Bartolo ND, Liu J, Harper WFM, Corrie AS, Jones MR. Directed assembly of defined oligomeric photosynthetic reaction centres through adaptation with programmable extra-membrane coiled-coil interfaces. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1829-1839. [PMID: 27614060 PMCID: PMC5084686 DOI: 10.1016/j.bbabio.2016.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/25/2016] [Accepted: 09/06/2016] [Indexed: 11/27/2022]
Abstract
A challenge associated with the utilisation of bioenergetic proteins in new, synthetic energy transducing systems is achieving efficient and predictable self-assembly of individual components, both natural and man-made, into a functioning macromolecular system. Despite progress with water-soluble proteins, the challenge of programming self-assembly of integral membrane proteins into non-native macromolecular architectures remains largely unexplored. In this work it is shown that the assembly of dimers, trimers or tetramers of the naturally monomeric purple bacterial reaction centre can be directed by augmentation with an α-helical peptide that self-associates into extra-membrane coiled-coil bundle. Despite this induced oligomerisation the assembled reaction centres displayed normal spectroscopic properties, implying preserved structural and functional integrity. Mixing of two reaction centres modified with mutually complementary α-helical peptides enabled the assembly of heterodimers in vitro, pointing to a generic strategy for assembling hetero-oligomeric complexes from diverse modified or synthetic components. Addition of two coiled-coil peptides per reaction centre monomer was also tolerated despite the challenge presented to the pigment-protein assembly machinery of introducing multiple self-associating sequences. These findings point to a generalised approach where oligomers or longer range assemblies of multiple light harvesting and/or redox proteins can be constructed in a manner that can be genetically-encoded, enabling the construction of new, designed bioenergetic systems in vivo or in vitro. Reaction centre monomers are engineered to assemble as oligomers in vivo. A fused coiled coil bundle programs dimer, trimer and tetramer formation. Assembled oligomeric reaction centres are structurally and functionally intact. Coiled coils can be used to assemble reaction centre hetero-oligomers in vitro. Addition of two coiled-coil peptides per reaction centre monomer is tolerated.
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Affiliation(s)
- David J K Swainsbury
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - Robert L Harniman
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Natalie D Di Bartolo
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - Juntai Liu
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - William F M Harper
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - Alexander S Corrie
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
| | - Michael R Jones
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom.
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11
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Berezovskaya Y, Porrini M, Nortcliffe C, Barran PE. The use of ion mobility mass spectrometry to assist protein design: a case study on zinc finger fold versus coiled coil interactions. Analyst 2016; 140:2847-56. [PMID: 25734188 DOI: 10.1039/c4an00427b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dramatic conformational change in zinc fingers on binding metal ions for DNA recognition makes their structure-function behaviour an attractive target to mimic in de novo designed peptides. Mass spectrometry, with its high throughput and low sample consumption provides insight into how primary amino acid sequence can encode stable tertiary fold. We present here the use of ion mobility mass spectrometry (IM-MS) coupled with molecular dynamics (MD) simulations as a rapid analytical platform to inform de novo design efforts for peptide-metal and peptide-peptide interactions. A dual peptide-based synthetic system, ZiCop based on a zinc finger peptide motif, and a coiled coil partner peptide Pp, have been investigated. Titration mass spectrometry determines the relative binding affinities of different divalent metal ions as Zn(2+) > Co(2+) ≫ Ca(2+). With collision induced dissociation (CID), we probe complex stability, and establish that peptide-metal interactions are stronger and more 'specific' than those of peptide-peptide complexes, and the anticipated hetero-dimeric complex is more stable than the two homo-dimers. Collision cross-sections (CCS) measurements by IM-MS reveal increased stability with respect to unfolding of the metal-bound peptide over its apo-form, and further, larger collision cross sections for the hetero-dimeric forms suggest that dimeric species formed in the absence of metal are coiled coil like. MD supports these structural assignments, backed up by data from visible light absorbance measurements.
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12
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Kobayashi N, Yanase K, Sato T, Unzai S, Hecht MH, Arai R. Self-Assembling Nano-Architectures Created from a Protein Nano-Building Block Using an Intermolecularly Folded Dimeric de Novo Protein. J Am Chem Soc 2015; 137:11285-93. [PMID: 26120734 DOI: 10.1021/jacs.5b03593] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The design of novel proteins that self-assemble into supramolecular complexes is an important step in the development of synthetic biology and nanotechnology. Recently, we described the three-dimensional structure of WA20, a de novo protein that forms an intermolecularly folded dimeric 4-helix bundle (PDB code 3VJF ). To harness the unusual intertwined structure of WA20 for the self-assembly of supramolecular nanostructures, we created a protein nanobuilding block (PN-Block), called WA20-foldon, by fusing the dimeric structure of WA20 to the trimeric foldon domain of fibritin from bacteriophage T4. The WA20-foldon fusion protein was expressed in the soluble fraction in Escherichia coli, purified, and shown to form several homooligomeric forms. The stable oligomeric forms were further purified and characterized by a range of biophysical techniques. Size exclusion chromatography, multiangle light scattering, analytical ultracentrifugation, and small-angle X-ray scattering (SAXS) analyses indicate that the small (S form), middle (M form), and large (L form) forms of the WA20-foldon oligomers exist as hexamer (6-mer), dodecamer (12-mer), and octadecamer (18-mer), respectively. These findings suggest that the oligomers in multiples of 6-mer are stably formed by fusing the interdigitated dimer of WA20 with the trimer of foldon domain. Pair-distance distribution functions obtained from the Fourier inversion of the SAXS data suggest that the S and M forms have barrel- and tetrahedron-like shapes, respectively. These results demonstrate that the de novo WA20-foldon is an effective building block for the creation of self-assembling artificial nanoarchitectures.
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Affiliation(s)
- Naoya Kobayashi
- Japan Society for the Promotion of Science , Chiyoda, Tokyo 102-8471, Japan
| | | | | | - Satoru Unzai
- Graduate School of Medical Life Science, Yokohama City University , Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Michael H Hecht
- Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States
| | - Ryoichi Arai
- Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University , Matsumoto, Nagano 390-8621, Japan
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13
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Currin A, Swainston N, Day PJ, Kell DB. Synthetic biology for the directed evolution of protein biocatalysts: navigating sequence space intelligently. Chem Soc Rev 2015; 44:1172-239. [PMID: 25503938 PMCID: PMC4349129 DOI: 10.1039/c4cs00351a] [Citation(s) in RCA: 247] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Indexed: 12/21/2022]
Abstract
The amino acid sequence of a protein affects both its structure and its function. Thus, the ability to modify the sequence, and hence the structure and activity, of individual proteins in a systematic way, opens up many opportunities, both scientifically and (as we focus on here) for exploitation in biocatalysis. Modern methods of synthetic biology, whereby increasingly large sequences of DNA can be synthesised de novo, allow an unprecedented ability to engineer proteins with novel functions. However, the number of possible proteins is far too large to test individually, so we need means for navigating the 'search space' of possible protein sequences efficiently and reliably in order to find desirable activities and other properties. Enzymologists distinguish binding (Kd) and catalytic (kcat) steps. In a similar way, judicious strategies have blended design (for binding, specificity and active site modelling) with the more empirical methods of classical directed evolution (DE) for improving kcat (where natural evolution rarely seeks the highest values), especially with regard to residues distant from the active site and where the functional linkages underpinning enzyme dynamics are both unknown and hard to predict. Epistasis (where the 'best' amino acid at one site depends on that or those at others) is a notable feature of directed evolution. The aim of this review is to highlight some of the approaches that are being developed to allow us to use directed evolution to improve enzyme properties, often dramatically. We note that directed evolution differs in a number of ways from natural evolution, including in particular the available mechanisms and the likely selection pressures. Thus, we stress the opportunities afforded by techniques that enable one to map sequence to (structure and) activity in silico, as an effective means of modelling and exploring protein landscapes. Because known landscapes may be assessed and reasoned about as a whole, simultaneously, this offers opportunities for protein improvement not readily available to natural evolution on rapid timescales. Intelligent landscape navigation, informed by sequence-activity relationships and coupled to the emerging methods of synthetic biology, offers scope for the development of novel biocatalysts that are both highly active and robust.
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Affiliation(s)
- Andrew Currin
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- School of Chemistry , The University of Manchester , Manchester M13 9PL , UK
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
| | - Neil Swainston
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
- School of Computer Science , The University of Manchester , Manchester M13 9PL , UK
| | - Philip J. Day
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
- Faculty of Medical and Human Sciences , The University of Manchester , Manchester M13 9PT , UK
| | - Douglas B. Kell
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- School of Chemistry , The University of Manchester , Manchester M13 9PL , UK
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
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14
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Carter NA, Grove TZ. Repeat-Proteins Films Exhibit Hierarchical Anisotropic Mechanical Properties. Biomacromolecules 2015; 16:706-14. [DOI: 10.1021/bm501578j] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Nathan A. Carter
- Department of Chemistry (0212), Virginia Tech, 2107 Hahn Hall
South, Blacksburg, Virginia 24060, United States
| | - Tijana Zarkovic Grove
- Department of Chemistry (0212), Virginia Tech, 2107 Hahn Hall
South, Blacksburg, Virginia 24060, United States
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15
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Schyfter P. How a 'drive to make' shapes synthetic biology. STUDIES IN HISTORY AND PHILOSOPHY OF BIOLOGICAL AND BIOMEDICAL SCIENCES 2013; 44:632-640. [PMID: 23777680 DOI: 10.1016/j.shpsc.2013.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A commitment to 'making'--creating or producing things--can shape scientific and technological fields in important ways. This article demonstrates this by exploring synthetic biology, a field committed to making use of advanced techniques from molecular biology in order to make with living matter (and for some, to engineer living matter). I describe and analyse how this field's 'drive to make' shapes its organisational, methodological, epistemological, and ontological character. Synthetic biologists' ambition to make helps determine how their field demarcates itself, sets appropriate methods and practices, construes the purpose and character of knowledge, and views the things of the living world. Using empirical data from extensive ethnographic and interview-based research, I discuss the importance of seemingly simple and unimportant commitments-in this case, a focus on the making of things rather than the production of knowledge claims. I conclude by examining the ramifications of this line of research for studies of science and technology.
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Affiliation(s)
- Pablo Schyfter
- Science, Technology and Innovation Studies, The University of Edinburgh, Old Surgeons' Hall, High School Yards, Edinburgh EH1 1LZ, UK.
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16
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Burton AJ, Thomas F, Agnew C, Hudson KL, Halford SE, Brady RL, Woolfson DN. Accessibility, Reactivity, and Selectivity of Side Chains within a Channel of de Novo Peptide Assembly. J Am Chem Soc 2013; 135:12524-7. [DOI: 10.1021/ja4053027] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Antony J. Burton
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Franziska Thomas
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Christopher Agnew
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, United Kingdom
| | - Kieran L. Hudson
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Stephen E. Halford
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, United Kingdom
| | - R. Leo Brady
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, United Kingdom
| | - Derek N. Woolfson
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, United Kingdom
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17
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Selgrade DF, Lohmueller JJ, Lienert F, Silver PA. Protein scaffold-activated protein trans-splicing in mammalian cells. J Am Chem Soc 2013; 135:7713-9. [PMID: 23621664 DOI: 10.1021/ja401689b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Conditional protein splicing is a powerful biotechnological tool that can be used to rapidly and post-translationally control the activity of a given protein. Here we demonstrate a novel conditional splicing system in which a genetically encoded protein scaffold induces the splicing and activation of an enzyme in mammalian cells. In this system the protein scaffold binds to two inactive split intein/enzyme extein protein fragments leading to intein fragment complementation, splicing, and activation of the firefly luciferase enzyme. We first demonstrate the ability of antiparallel coiled-coils (CCs) to mediate splicing between two intein fragments, effectively creating two new split inteins. We then generate and test two versions of the scaffold-induced splicing system using two pairs of CCs. Finally, we optimize the linker lengths of the proteins in the system and demonstrate 13-fold activation of luciferase by the scaffold compared to the activity of negative controls. Our protein scaffold-triggered conditional splicing system is an effective strategy to control enzyme activity using a protein input, enabling enhanced genetic control over protein splicing and the potential creation of splicing-based protein sensors and autoregulatory systems.
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Affiliation(s)
- Daniel F Selgrade
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
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18
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Armstrong CT, Watkins DW, Anderson JLR. Constructing manmade enzymes for oxygen activation. Dalton Trans 2012; 42:3136-50. [PMID: 23076271 DOI: 10.1039/c2dt32010j] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Natural oxygenases catalyse the insertion of oxygen into an impressive array of organic substrates with exquisite efficiency, specificity and power unparalleled by current biomimetic catalysts. However, their true potential to provide tailor-made oxygenation catalysts remains largely untapped, perhaps a consequence of the evolutionary complexity imprinted into their three-dimensional structures through millennia of exposure to parallel selective pressures. In this perspective we describe how we may take inspiration from natural enzymes to design manmade oxygenase enzymes free from such complexity. We explore the differing chemistries accessed by natural oxygenases and outline a stepwise methodology whereby functional elements key to oxygenase catalysis are assembled within artificially designed protein scaffolds.
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Affiliation(s)
- Craig T Armstrong
- School of Biochemistry, University of Bristol, University Walk, Bristol, BS8 1TD, UK
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19
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New currency for old rope: from coiled-coil assemblies to α-helical barrels. Curr Opin Struct Biol 2012; 22:432-41. [DOI: 10.1016/j.sbi.2012.03.002] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 03/01/2012] [Accepted: 03/01/2012] [Indexed: 11/18/2022]
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20
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Fletcher JM, Boyle AL, Bruning M, Bartlett GJ, Vincent TL, Zaccai NR, Armstrong CT, Bromley EHC, Booth PJ, Brady RL, Thomson AR, Woolfson DN. A basis set of de novo coiled-coil peptide oligomers for rational protein design and synthetic biology. ACS Synth Biol 2012; 1:240-50. [PMID: 23651206 DOI: 10.1021/sb300028q] [Citation(s) in RCA: 182] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Protein engineering, chemical biology, and synthetic biology would benefit from toolkits of peptide and protein components that could be exchanged reliably between systems while maintaining their structural and functional integrity. Ideally, such components should be highly defined and predictable in all respects of sequence, structure, stability, interactions, and function. To establish one such toolkit, here we present a basis set of de novo designed α-helical coiled-coil peptides that adopt defined and well-characterized parallel dimeric, trimeric, and tetrameric states. The designs are based on sequence-to-structure relationships both from the literature and analysis of a database of known coiled-coil X-ray crystal structures. These give foreground sequences to specify the targeted oligomer state. A key feature of the design process is that sequence positions outside of these sites are considered non-essential for structural specificity; as such, they are referred to as the background, are kept non-descript, and are available for mutation as required later. Synthetic peptides were characterized in solution by circular-dichroism spectroscopy and analytical ultracentrifugation, and their structures were determined by X-ray crystallography. Intriguingly, a hitherto widely used empirical rule-of-thumb for coiled-coil dimer specification does not hold in the designed system. However, the desired oligomeric state is achieved by database-informed redesign of that particular foreground and confirmed experimentally. We envisage that the basis set will be of use in directing and controlling protein assembly, with potential applications in chemical and synthetic biology. To help with such endeavors, we introduce Pcomp, an on-line registry of peptide components for protein-design and synthetic-biology applications.
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Affiliation(s)
- Jordan M. Fletcher
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Aimee L. Boyle
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Marc Bruning
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Gail J. Bartlett
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Thomas L. Vincent
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Nathan R. Zaccai
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | - Craig T. Armstrong
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | | | - Paula J. Booth
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | - R. Leo Brady
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
| | - Andrew R. Thomson
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
| | - Derek N. Woolfson
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8
1TS, U.K
- School of Biochemistry, University of Bristol, Medical Sciences Building, University
Walk, Bristol BS8 1TD, U.K
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21
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Collier JH, Segura T. Evolving the use of peptides as components of biomaterials. Biomaterials 2011; 32:4198-204. [PMID: 21515167 PMCID: PMC3389831 DOI: 10.1016/j.biomaterials.2011.02.030] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Accepted: 02/12/2011] [Indexed: 01/05/2023]
Abstract
This manuscript is part of a debate on the statement that "the use of short synthetic adhesion peptides, like RGD, is the best approach in the design of biomaterials that guide cell behavior for regenerative medicine and tissue engineering". We take the position that although there are some acknowledged disadvantages of using short peptide ligands within biomaterials, it is not necessary to discard the notion of using peptides within biomaterials entirely, but rather to reinvent and evolve their use. Peptides possess advantageous chemical definition, access to non-native chemistries, amenability to de novo design, and applicability within parallel approaches. Biomaterials development programs that require such aspects may benefit from a peptide-based strategy.
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Affiliation(s)
- Joel H. Collier
- Assistant Professor, Department of Surgery, University of Chicago, 5841 S. Maryland Ave., Mail Code 5032, Chicago, IL 60637, (773) 834-4161, (773) 834-4546 (fax)
| | - Tatiana Segura
- Assistant Professor, 420 Westwood Plaza, 5531 Boelter Hall, Los Angeles, CA 90095, (310) 206 3980
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22
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Yoshizumi A, Fletcher JM, Yu Z, Persikov AV, Bartlett GJ, Boyle AL, Vincent TL, Woolfson DN, Brodsky B. Designed coiled coils promote folding of a recombinant bacterial collagen. J Biol Chem 2011; 286:17512-20. [PMID: 21454493 DOI: 10.1074/jbc.m110.217364] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Collagen triple helices fold slowly and inefficiently, often requiring adjacent globular domains to assist this process. In the Streptococcus pyogenes collagen-like protein Scl2, a V domain predicted to be largely α-helical, occurs N-terminal to the collagen triple helix (CL). Here, we replace this natural trimerization domain with a de novo designed, hyperstable, parallel, three-stranded, α-helical coiled coil (CC), either at the N terminus (CC-CL) or the C terminus (CL-CC) of the collagen domain. CD spectra of the constructs are consistent with additivity of independently and fully folded CC and CL domains, and the proteins retain their distinctive thermal stabilities, CL at ∼37 °C and CC at >90 °C. Heating the hybrid proteins to 50 °C unfolds CL, leaving CC intact, and upon cooling, the rate of CL refolding is somewhat faster for CL-CC than for CC-CL. A construct with coiled coils on both ends, CC-CL-CC, retains the ∼37 °C thermal stability for CL but shows less triple helix at low temperature and less denaturation at 50 °C. Most strikingly however, in CC-CL-CC, the CL refolds slower than in either CC-CL or CL-CC by almost two orders of magnitude. We propose that a single CC promotes folding of the CL domain via nucleation and in-register growth from one end, whereas initiation and growth from both ends in CC-CL-CC results in mismatched registers that frustrate folding. Bioinformatics analysis of natural collagens lends support to this because, where present, there is generally only one coiled-coil domain close to the triple helix, and it is nearly always N-terminal to the collagen repeat.
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Affiliation(s)
- Ayumi Yoshizumi
- Department of Biochemistry, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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23
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Abstract
In recent years our ability to design and assemble peptide-based materials and objects de novo (i.e. from first principles) has improved considerably. This brings us to a point where the resulting assemblies are quite sophisticated and amenable to engineering in new functions. Whilst such systems could be used in a variety of ways, biological applications are of particular interest because of the demand for biocompatible, readily produced systems with potential as drug-delivery agents, components of biosensors and scaffolds for 3D cell and tissue culture. This tutorial review describes the building blocks (or tectons) that are being used in peptide assembly, highlights a range of materials and objects that have been produced, notably hydrogels and virus-like particles, and introduces a number of potential applications for the designs.
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Affiliation(s)
- Aimee L Boyle
- School of Chemistry, University of Bristol, Cantocks Close, Bristol, BS8 1TS, UK
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24
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Lee J, Blaber SI, Dubey VK, Blaber M. A polypeptide "building block" for the β-trefoil fold identified by "top-down symmetric deconstruction". J Mol Biol 2011; 407:744-63. [PMID: 21315087 DOI: 10.1016/j.jmb.2011.02.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 01/31/2011] [Accepted: 02/02/2011] [Indexed: 12/31/2022]
Abstract
Fibroblast growth factor-1, a member of the 3-fold symmetric β-trefoil fold, was subjected to a series of symmetric constraint mutations in a process termed "top-down symmetric deconstruction." The mutations enforced a cumulative exact 3-fold symmetry upon symmetrically equivalent positions within the protein and were combined with a stability screen. This process culminated in a β-trefoil protein with exact 3-fold primary-structure symmetry that exhibited excellent folding and stability properties. Subsequent fragmentation of the repeating primary-structure motif yielded a 42-residue polypeptide capable of spontaneous assembly as a homotrimer, producing a thermostable β-trefoil architecture. The results show that despite pronounced reduction in sequence complexity, pure symmetry in the design of a foldable, thermostable β-trefoil fold is possible. The top-down symmetric deconstruction approach provides a novel alternative means to successfully identify a useful polypeptide "building block" for subsequent "bottom-up" de novo design of target protein architecture.
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Affiliation(s)
- Jihun Lee
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306-4300, USA
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25
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Bromley EHC, Channon KJ. Alpha-helical peptide assemblies giving new function to designed structures. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 103:231-75. [PMID: 21999998 PMCID: PMC7150058 DOI: 10.1016/b978-0-12-415906-8.00001-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
The design of alpha-helical tectons for self-assembly is maturing as a science. We have now reached the point where many different coiled-coil topologies can be reliably produced and validated in synthetic systems and the field is now moving on towards more complex, discrete structures and applications. Similarly the design of infinite or fiber assemblies has also matured, with the creation fibers that have been modified or functionalized in a variety of ways. This chapter discusses the progress made in both of these areas as well as outlining the challenges still to come.
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26
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Zaytsev DV, Xie F, Mukherjee M, Bludin A, Demeler B, Breece RM, Tierney DL, Ogawa MY. Nanometer to millimeter scale peptide-porphyrin materials. Biomacromolecules 2010; 11:2602-9. [PMID: 20804210 PMCID: PMC2952671 DOI: 10.1021/bm100540t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
AQ-Pal14 is a 30-residue polypeptide that was designed to form an α-helical coiled coil that contains a metal-binding 4-pyridylalanine residue on its solvent-exposed surface. However, characterization of this peptide shows that it exists as a three-stranded coiled coil, not a two-stranded one as predicted from its design. Reaction with cobalt(III) protoporphyrin IX (Co-PPIX) produces a six-coordinate Co-PPIX(AQ-Pal14)(2) species that creates two coiled-coil oligomerization domains coordinated to opposite faces of the porphyrin ring. It is found that this species undergoes a buffer-dependent self-assembly process: nanometer-scale globular materials were formed when these components were reacted in unbuffered H(2)O, while millimeter-scale, rod-like materials were prepared when the reaction was performed in phosphate buffer (20 mM, pH 7). It is suggested that assembly of the globular material is dictated by the conformational properties of the coiled-coil forming AQ-Pal14 peptide, whereas that of the rod-like material involves interactions between Co-PPIX and phosphate ion.
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Affiliation(s)
- Daniil V. Zaytsev
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403
| | - Fei Xie
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403
| | - Madmuhita Mukherjee
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403
| | - Alexey Bludin
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403
| | - Borries Demeler
- Center for Analytical Ultracentrifugation of Macromolecular Assemblies, University of Texas Health Science Center, San Antonio, TX 78229
| | - Robert M. Breece
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056
| | - David L. Tierney
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056
| | - Michael Y. Ogawa
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403
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27
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Whitesides GM, Lipomi DJ. Soft nanotechnology: “structure”vs.“function”. Faraday Discuss 2009; 143:373-84. [DOI: 10.1039/b917540g] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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