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Elsayed YY, Kühl T, Imhof D. Edman Degradation Reveals Unequivocal Analysis of the Disulfide Connectivity in Peptides and Proteins. Anal Chem 2024; 96:4057-4066. [PMID: 38407829 DOI: 10.1021/acs.analchem.3c04229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Disulfide bridges in peptides and proteins play an essential role in maintaining their conformation, structural integrity, and consequently function. Despite ongoing efforts, it is still not possible to detect disulfide bonds and the connectivity of multiply bridged peptides directly through a simple and sufficiently validated protein sequencing or peptide mapping method. Partial or complete reduction and chemical cysteine modification are required as initial steps, followed by the application of a proper detection method. Edman degradation (ED) has been used for primary sequence determination but is largely neglected since the establishment of mass spectrometry (MS)-based protein sequencing. Here, we evaluated and thoroughly characterized the phenyl thiohydantoin (PTH) cysteine derivatives PTH-S-methyl cysteine and PTH-S-carbamidomethyl cysteine as bioanalytical standards for cysteine detection and quantification as well as for the elucidation of the disulfide connectivity in peptides by ED. Validation of the established derivatives was performed according to the guidelines of the International Committee of Harmonization on bioanalytical method validation, and their analytical properties were confirmed as reference standards. A series of model peptides was sequenced to test the usability of the PTH-Cys-derivatives as standards, whereas the native disulfide-bonded peptides CCAP-vil, μ-conotoxin KIIIA, and human insulin were used as case studies to determine their disulfide bond connectivity completely independent of MS analysis.
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Affiliation(s)
- Yomnah Y Elsayed
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, Bonn 53121, Germany
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Ain Shams University, Organization of African Unity St, Cairo 11566, Egypt
| | - Toni Kühl
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, Bonn 53121, Germany
| | - Diana Imhof
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, Bonn 53121, Germany
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2
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Chen Z, Lim YW, Neo JY, Ting Chan RS, Koh LQ, Yuen TY, Lim YH, Johannes CW, Gates ZP. De Novo Sequencing of Synthetic Bis-cysteine Peptide Macrocycles Enabled by "Chemical Linearization" of Compound Mixtures. Anal Chem 2023; 95:14870-14878. [PMID: 37724843 PMCID: PMC10569172 DOI: 10.1021/acs.analchem.3c01742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 09/04/2023] [Indexed: 09/21/2023]
Abstract
A "chemical linearization" approach was applied to synthetic peptide macrocycles to enable their de novo sequencing from mixtures using nanoliquid chromatography-tandem mass spectrometry (nLC-MS/MS). This approach─previously applied to individual macrocycles but not to mixtures─involves cleavage of the peptide backbone at a defined position to give a product capable of generating sequence-determining fragment ions. Here, we first established the compatibility of "chemical linearization" by Edman degradation with a prominent macrocycle scaffold based on bis-Cys peptides cross-linked with the m-xylene linker, which are of major significance in therapeutics discovery. Then, using macrocycle libraries of known sequence composition, the ability to recover accurate de novo assignments to linearized products was critically tested using performance metrics unique to mixtures. Significantly, we show that linearized macrocycles can be sequenced with lower recall compared to linear peptides but with similar accuracy, which establishes the potential of using "chemical linearization" with synthetic libraries and selection procedures that yield compound mixtures. Sodiated precursor ions were identified as a significant source of high-scoring but inaccurate assignments, with potential implications for improving automated de novo sequencing more generally.
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Affiliation(s)
- Zhi’ang Chen
- Institute
of Molecular and Cell Biology (IMCB), Agency
for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Yi Wee Lim
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Jin Yong Neo
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Rachel Shu Ting Chan
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Li Quan Koh
- Institute
of Molecular and Cell Biology (IMCB), Agency
for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Tsz Ying Yuen
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Yee Hwee Lim
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
| | - Charles W. Johannes
- Institute
of Molecular and Cell Biology (IMCB), Agency
for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore
| | - Zachary P. Gates
- Institute
of Molecular and Cell Biology (IMCB), Agency
for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore
- Institute
of Sustainability for Chemicals, Energy and Environment (ISCE), Agency for Science, Technology
and Research (A*STAR), 8 Biomedical Grove, #07-01 Neuros, Singapore 138665, Republic
of Singapore
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3
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Guo L, Kong D, Liu J, Zhan L, Luo L, Zheng W, Zheng Q, Chen C, Sun S. Breast cancer heterogeneity and its implication in personalized precision therapy. Exp Hematol Oncol 2023; 12:3. [PMID: 36624542 PMCID: PMC9830930 DOI: 10.1186/s40164-022-00363-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 12/29/2022] [Indexed: 01/11/2023] Open
Abstract
Breast cancer heterogeneity determines cancer progression, treatment effects, and prognosis. However, the precise mechanism for this heterogeneity remains unknown owing to its complexity. Here, we summarize the origins of breast cancer heterogeneity and its influence on disease progression, recurrence, and therapeutic resistance. We review the possible mechanisms of heterogeneity and the research methods used to analyze it. We also highlight the importance of cell interactions for the origins of breast cancer heterogeneity, which can be further categorized into cooperative and competitive interactions. Finally, we provide new insights into precise individual treatments based on heterogeneity.
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Affiliation(s)
- Liantao Guo
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China
| | - Deguang Kong
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China
| | - Jianhua Liu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China
| | - Ling Zhan
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China
| | - Lan Luo
- Department of Breast Surgery, The Affiliated Hospital of Guizhou Medical University, No. 28 Guiyi Road, Yunyan District, Guiyang, 550001, Guizhou, China
| | - Weijie Zheng
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China
| | - Qingyuan Zheng
- Department of Urology, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China
| | - Chuang Chen
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China.
| | - Shengrong Sun
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, No. 238 Jiefang Road, Wuchang District, Wuhan, 430060, Hubei, China.
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Yamini C, Sharmila G, Muthukumaran C, Pavithran K, Manojkumar N. Proteomic perspectives on thermotolerant microbes: an updated review. Mol Biol Rep 2021. [PMID: 34671903 DOI: 10.1007/s11033-021-06805-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 10/04/2021] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Thermotolerant microbes are a group of microorganisms that survive in elevated temperatures. The thermotolerant microbes, which are found in geothermal heat zones, grow at temperatures of or above 45°C. The proteins present in such microbes are optimally active at these elevated temperatures. Hence, therefore, serves as an advantage in various biotechnological applications. In the last few years, scientists have tried to understand the molecular mechanisms behind the maintenance of the structural integrity of the cell and to study the stability of various thermotolerant proteins at extreme temperatures. Proteomic analysis is the solution for this search. Applying novel proteomic tools determines the proteins involved in the thermostability of microbes at elevated temperatures. METHODS Advanced proteomic techniques like Mass spectrometry, nano-LC-MS, protein microarray, ICAT, iTRAQ, and SILAC could enable the screening and identification of novel thermostable proteins. RESULTS This review provides up-to-date details on the protein signature of various thermotolerant microbes analyzed through advanced proteomic tools concerning relevant research articles. The protein complex composition from various thermotolerant microbes cultured at different temperatures, their structural arrangement, and functional efficiency of the protein was reviewed and reported. CONCLUSION This review provides an overview of thermotolerant microbes, their enzymes, and the proteomic tools implemented to characterize them. This article also reviewed a comprehensive view of the current proteomic approaches for protein profiling in thermotolerant microbes.
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Abstract
Peptides are widely used in pharmaceutical industry as active pharmaceutical ingredients, versatile tools in drug discovery, and for drug delivery. They find themselves at the crossroads of small molecules and proteins, possessing favorable tissue penetration and the capability to engage into specific and high-affinity interactions with endogenous receptors. One of the commonly employed approaches in peptide discovery and design is to screen combinatorial libraries, comprising a myriad of peptide variants of either chemical or biological origin. In this review, we focus mainly on recombinant peptide libraries, discussing different platforms for their display or expression, and various diversification strategies for library design. We take a look at well-established technologies as well as new developments and future directions.
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Affiliation(s)
| | - Tomaž Bratkovič
- Department of Pharmaceutical Biology, Faculty of Pharmacy, University of Ljubljana, Aškerčeva Cesta 7, SI-1000 Ljubljana, Slovenia;
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Vinogradov AA, Gates ZP, Zhang C, Quartararo AJ, Halloran KH, Pentelute BL. Library Design-Facilitated High-Throughput Sequencing of Synthetic Peptide Libraries. ACS Comb Sci 2017; 19:694-701. [PMID: 28892357 PMCID: PMC5818986 DOI: 10.1021/acscombsci.7b00109] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A methodology to achieve high-throughput de novo sequencing of synthetic peptide mixtures is reported. The approach leverages shotgun nanoliquid chromatography coupled with tandem mass spectrometry-based de novo sequencing of library mixtures (up to 2000 peptides) as well as automated data analysis protocols to filter away incorrect assignments, noise, and synthetic side-products. For increasing the confidence in the sequencing results, mass spectrometry-friendly library designs were developed that enabled unambiguous decoding of up to 600 peptide sequences per hour while maintaining greater than 85% sequence identification rates in most cases. The reliability of the reported decoding strategy was additionally confirmed by matching fragmentation spectra for select authentic peptides identified from library sequencing samples. The methods reported here are directly applicable to screening techniques that yield mixtures of active compounds, including particle sorting of one-bead one-compound libraries and affinity enrichment of synthetic library mixtures performed in solution.
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Affiliation(s)
| | - Zachary P. Gates
- Department of Chemistry, Massachusetts Institute of Technology, 18-563, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Chi Zhang
- Department of Chemistry, Massachusetts Institute of Technology, 18-563, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Anthony J. Quartararo
- Department of Chemistry, Massachusetts Institute of Technology, 18-563, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Kathryn H. Halloran
- Department of Chemistry, Massachusetts Institute of Technology, 18-563, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Bradley L Pentelute
- Department of Chemistry, Massachusetts Institute of Technology, 18-563, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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Antón Palma B, Leff Gelman P, Medecigo Ríos M, Calva Nieves JC, Acevedo Ortuño R, Matus Ortega ME, Hernández Calderón JA, Hernández Miramontes R, Flores Zamora A, Salazar Juárez A. Generation of a novel monoclonal antibody that recognizes the alpha (α)-amidated isoform of a valine residue. BMC Neurosci 2015; 16:65. [PMID: 26463686 PMCID: PMC4603347 DOI: 10.1186/s12868-015-0206-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 10/01/2015] [Indexed: 11/10/2022] Open
Abstract
Background Alpha (α)-amidation of peptides is a mechanism required for the conversion of prohormones into functional peptide sequences that display biological activities, receptor recognition and signal transduction on target cells. Alpha (α)-amidation occurs in almost all species and amino acids identified in nature. C-terminal valine amide neuropeptides constitute the smallest group of functional peptide compounds identified in neurosecretory structures in vertebrate and invertebrate species. Methods The α-amidated isoform of valine residue (Val-CONH2) was conjugated to KLH-protein carrier and used to immunize mice. Hyperimmune animals displaying high titers of valine amide antisera were used to generate stable hybridoma-secreting mAbs. Three productive hybridoma (P15A4, P17C11, and P18C5) were tested against peptides antigens containing both the C-terminal α-amidated (–CONH2) and free α-carboxylic acid (−COO−) isovariant of the valine residue. Results P18C5 mAb displayed the highest specificity and selectivity against C-terminal valine amidated peptide antigens in different immunoassays. P18C5 mAb-immunoreactivity exhibited a wide distribution along the neuroaxis of the rat brain, particularly in brain areas that did not cross-match with the neuronal distribution of known valine amide neuropeptides (α-MSH, adrenorphin, secretin, UCN1-2). These brain regions varied in the relative amount of putative novel valine amide peptide immunoreactive material (nmol/μg protein) estimated through a fmol-sensitive solid-phase radioimmunoassay (RIA) raised for P18C5 mAb. Conclusions Our results demonstrate the versatility of a single mAb able to differentiate between two structural subdomains of a single amino acid. This mAb offers a wide spectrum of potential applications in research and medicine, whose uses may extend from a biological reagent (used to detect valine amidated peptide substances in fluids and tissues) to a detoxifying reagent (used to neutralize exogenous toxic amide peptide compounds) or as a specific immunoreagent in immunotherapy settings (used to reduce tumor growth and tumorigenesis) among many others.
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Affiliation(s)
- Benito Antón Palma
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Philippe Leff Gelman
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico. .,Department of Neuroscience, National Institute of Perinatology, Montes Urales # 800, 11000, México D.F., Mexico.
| | - Mayra Medecigo Ríos
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Juan Carlos Calva Nieves
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Rodolfo Acevedo Ortuño
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Maura Epifanía Matus Ortega
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Jorge Alberto Hernández Calderón
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Ricardo Hernández Miramontes
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Anabel Flores Zamora
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
| | - Alberto Salazar Juárez
- Molecular Neurobiology and Addictive Neurochemistry Laboratory, National Institute of Psychiatry, Calzada México-Xochimilco #101, 14370, México D.F., Mexico.
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9
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10
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Abstract
Our understanding of the different glycoconjugates present on cells, proteins and entire organisms is lagging far behind advances in genomics and proteomics. Carbohydrate sequencing and the synthesis of defined oligosaccharides are two key technologies that have contributed to progress in glycomics research. Synthetic tools and high-throughput experiments such as carbohydrate arrays are beginning to affect biological research. These techniques are now being applied to the development of carbohydrate-based diagnostics, vaccines and therapeutics.
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Affiliation(s)
- Peter H Seeberger
- Laboratory for Organic Chemistry, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland.
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Dormeyer W, Ott M, Schnölzer M. Probing lysine acetylation in proteins: strategies, limitations, and pitfalls of in vitro acetyltransferase assays. Mol Cell Proteomics 2005; 4:1226-39. [PMID: 15933374 DOI: 10.1074/mcp.m500047-mcp200] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The acetylation of proteins at specific lysine residues by acetyltransferase enzymes has emerged as a posttranslational modification of high biological impact. Although lysine acetylation in histone proteins is an integral part of the histone code the acetylation of a multitude of non-histone proteins was recently recognized as a regulatory signal in many cellular processes. New substrates of acetyltransferase enzymes are continuously identified, and the analysis of acetylation sites in proteins is increasingly performed by mass spectrometry. However, the characterization of lysine acetylation in proteins using mass spectrometric techniques has some limitations and pitfalls. The non-enzymatic cysteine acetylation especially can result in false-positive identification of acetylated proteins. Here we demonstrate the application of various mass spectrometric techniques such as matrix-assisted laser desorption/ionization and electrospray ionization mass spectrometry for the analysis of protein acetylation. We describe diverse combinations of biochemical methods useful to map the acetylation sites in proteins and discuss their advantages and limitations. As an example, we present a detailed analysis of the acetylation of the HIV-1 transactivator of transcription (Tat) protein, which is known to be acetylated in vivo by the acetyltransferases p300 and p300/CBP-associated factor (PCAF).
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Affiliation(s)
- Wilma Dormeyer
- Protein Analysis Facility, German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
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Kragol G, Otvos L, Feng J, Gerhard W, Wade JD. Synthesis of a disulfide-linked octameric peptide construct carrying three different antigenic determinants. Bioorg Med Chem Lett 2001; 11:1417-20. [PMID: 11378367 DOI: 10.1016/s0960-894x(01)00252-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In an effort to develop peptide vaccines against the influenza virus, we have successfully synthesized a disulfide-linked octameric homodimer that bears four copies of the influenza virus M2 protein ectodomain as well as two copies each of T-helper cell hemagglutinin epitopes, the I-E(d) restricted S1 and the I-A(d) restricted S2 fragments. Peptide attachment was via intermolecular disulfide formation from free sulfhydryl-bearing cysteine derivatives in solution. This reaction was efficient only when the amino-group of the cysteine was Fmoc-protected.
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Affiliation(s)
- G Kragol
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA.
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13
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Abstract
We describe the design and synthesis of a novel well characterized multi-peptide conjugate (MPC) system containing antigens from human malaria parasite and the Tat protein of HIV type-1 (HIV-1-Tat). Construction of the MPC utilizes Fmoc solid-phase peptide synthesis coupled with solution chemistry. In the first phase, a core template that serves as primary anchor for the synthesis and attachment of multiple antigens is synthesized. Serine(trityl) and multiple lysine branches with epsilon groups blocked during chain assembly are incorporated forming a tetrameric core. Cysteine whose side chain thiol serves to couple haloacetyl or S-protected haloacetyl peptides is added to complete assembly of the core template. Modification to the coupling solvent, addition of key amino acid derivatives (N-[1-hydroxy-4-methoxybenzyl]) in the peptide sequence allows the synthesis of base peptides on the core template with molecular mass greater than 7500 kDa. Base peptides are then reacted with high performance liquid chromatography purified haloacetyl peptides to generate multiple peptide conjugates with molecular masses of 10 to 13 kDa. MPC constructs thus formed are further characterized by matrix assisted laser desorption-time of flight mass spectroscopy (MALDI-MS), amino acid analysis, size exclusion chromatography, and SDS-polyacrylamide gel electrophoresis (PAGE). To our knowledge, this is the first report describing a chemically well defined multiple conjugate system with potential for development of synthetic subunit vaccines.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Drug Design
- Gene Products, tat/genetics
- Gene Products, tat/immunology
- HIV-1/genetics
- HIV-1/immunology
- Humans
- Molecular Sequence Data
- Molecular Weight
- Peptides/chemical synthesis
- Peptides/genetics
- Peptides/immunology
- Plasmodium falciparum/genetics
- Plasmodium falciparum/immunology
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- Vaccines, Conjugate/chemistry
- Vaccines, Conjugate/genetics
- Vaccines, Synthetic/chemistry
- Vaccines, Synthetic/genetics
- tat Gene Products, Human Immunodeficiency Virus
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Affiliation(s)
- R A Boykins
- Laboratory of Parasitic Biology and Biochemistry, Division of Allergenic Products and Parasitology, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20892, USA
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