1
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Sigal M, Matsumoto S, Beattie A, Katoh T, Suga H. Engineering tRNAs for the Ribosomal Translation of Non-proteinogenic Monomers. Chem Rev 2024; 124:6444-6500. [PMID: 38688034 PMCID: PMC11122139 DOI: 10.1021/acs.chemrev.3c00894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 02/21/2024] [Accepted: 04/10/2024] [Indexed: 05/02/2024]
Abstract
Ribosome-dependent protein biosynthesis is an essential cellular process mediated by transfer RNAs (tRNAs). Generally, ribosomally synthesized proteins are limited to the 22 proteinogenic amino acids (pAAs: 20 l-α-amino acids present in the standard genetic code, selenocysteine, and pyrrolysine). However, engineering tRNAs for the ribosomal incorporation of non-proteinogenic monomers (npMs) as building blocks has led to the creation of unique polypeptides with broad applications in cellular biology, material science, spectroscopy, and pharmaceuticals. Ribosomal polymerization of these engineered polypeptides presents a variety of challenges for biochemists, as translation efficiency and fidelity is often insufficient when employing npMs. In this Review, we will focus on the methodologies for engineering tRNAs to overcome these issues and explore recent advances both in vitro and in vivo. These efforts include increasing orthogonality, recruiting essential translation factors, and creation of expanded genetic codes. After our review on the biochemical optimizations of tRNAs, we provide examples of their use in genetic code manipulation, with a focus on the in vitro discovery of bioactive macrocyclic peptides containing npMs. Finally, an analysis of the current state of tRNA engineering is presented, along with existing challenges and future perspectives for the field.
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Affiliation(s)
- Maxwell Sigal
- Department of Chemistry,
Graduate School of Science, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Satomi Matsumoto
- Department of Chemistry,
Graduate School of Science, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Adam Beattie
- Department of Chemistry,
Graduate School of Science, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takayuki Katoh
- Department of Chemistry,
Graduate School of Science, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroaki Suga
- Department of Chemistry,
Graduate School of Science, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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2
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Patel AR, Lawer A, Bhadbhade M, Hunter L. The influence of backbone fluorination on the helicity of α/γ-hybrid peptides. Org Biomol Chem 2024; 22:1608-1612. [PMID: 38305470 DOI: 10.1039/d3ob02016a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Peptides that are composed of an alternating pattern of α- and γ-amino acids are potentially valuable as metabolism-resistant bioactive agents. For optimal function, some kind of conformational restriction is usually required to either stabilize the dominant 12-helix, or else to divert the peptide away from this conformation in a controlled way. Herein, we explore stereoselective fluorination as a method for controlling the conformations of α/γ-hybrid peptides. We show through a combination of X-ray, NMR and CD analyses that fluorination can either stabilize or disrupt the 12-helix, depending on the fluorine stereochemistry. These findings could inform the ongoing development of diverse functional hybrid peptides.
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Affiliation(s)
| | - Aggie Lawer
- School of Chemistry, University of New South Wales (UNSW), Sydney, Australia.
| | - Mohan Bhadbhade
- Mark Wainwright Analytical Centre, University of New South Wales (UNSW), Sydney, Australia
| | - Luke Hunter
- School of Chemistry, University of New South Wales (UNSW), Sydney, Australia.
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3
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Miura T, Malla TR, Owen CD, Tumber A, Brewitz L, McDonough MA, Salah E, Terasaka N, Katoh T, Lukacik P, Strain-Damerell C, Mikolajek H, Walsh MA, Kawamura A, Schofield CJ, Suga H. In vitro selection of macrocyclic peptide inhibitors containing cyclic γ 2,4-amino acids targeting the SARS-CoV-2 main protease. Nat Chem 2023:10.1038/s41557-023-01205-1. [PMID: 37217786 DOI: 10.1038/s41557-023-01205-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 04/14/2023] [Indexed: 05/24/2023]
Abstract
γ-Amino acids can play important roles in the biological activities of natural products; however, the ribosomal incorporation of γ-amino acids into peptides is challenging. Here we report how a selection campaign employing a non-canonical peptide library containing cyclic γ2,4-amino acids resulted in the discovery of very potent inhibitors of the SARS-CoV-2 main protease (Mpro). Two kinds of cyclic γ2,4-amino acids, cis-3-aminocyclobutane carboxylic acid (γ1) and (1R,3S)-3-aminocyclopentane carboxylic acid (γ2), were ribosomally introduced into a library of thioether-macrocyclic peptides. One resultant potent Mpro inhibitor (half-maximal inhibitory concentration = 50 nM), GM4, comprising 13 residues with γ1 at the fourth position, manifests a 5.2 nM dissociation constant. An Mpro:GM4 complex crystal structure reveals the intact inhibitor spans the substrate binding cleft. The γ1 interacts with the S1' catalytic subsite and contributes to a 12-fold increase in proteolytic stability compared to its alanine-substituted variant. Knowledge of interactions between GM4 and Mpro enabled production of a variant with a 5-fold increase in potency.
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Affiliation(s)
- Takashi Miura
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Tika R Malla
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - C David Owen
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, UK
- Research Complex at Harwell, Harwell Science & Innovation Campus, Didcot, UK
| | - Anthony Tumber
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Lennart Brewitz
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Michael A McDonough
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Eidarus Salah
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Naohiro Terasaka
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Takayuki Katoh
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Petra Lukacik
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, UK
- Research Complex at Harwell, Harwell Science & Innovation Campus, Didcot, UK
| | - Claire Strain-Damerell
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, UK
- Research Complex at Harwell, Harwell Science & Innovation Campus, Didcot, UK
| | - Halina Mikolajek
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, UK
- Research Complex at Harwell, Harwell Science & Innovation Campus, Didcot, UK
| | - Martin A Walsh
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, UK
- Research Complex at Harwell, Harwell Science & Innovation Campus, Didcot, UK
| | - Akane Kawamura
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
- Chemistry - School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Christopher J Schofield
- Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
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4
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Debnath S, Ghosh S, Kumar D, Vasudev PG, Satpati P, Chatterjee S. Effect of differential backbone di-substitution of gamma amino acid residues on the conformation and assembly of their Fmoc derivatives in solid and solution states. Chem Asian J 2022; 17:e202200356. [PMID: 35603989 DOI: 10.1002/asia.202200356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/23/2022] [Indexed: 11/11/2022]
Abstract
We studied the effect of variable backbone dimethyl-substitution of γ amino acid residues (γ 2,2 , γ 3,3 and γ 4,4 ) on the conformation and assembly, in crystals and solution of their Fmoc derivatives. Crystal structure of γ 2,2 and γ 4,4 derivatives showed distinct conformations (open/close for γ 2,2 /γ 4,4 ) that differed in torsion angles, hydrogen-bonding and most importantly the π-π Fmoc-stacking interactions (relatively favorable for γ 4,4 -close). Fmoc derivatives existed in an equilibrium between major-monomeric (low energy, non-hydrogen bonded) and minor-dimeric (high energy, hydrogen bonded) populations in solution. Rate of major/minor population exchange was dependent on the position of substitution, highest being for γ 4,4 derivative. In solution, assembly of Fmoc derivatives was solvent dependent, but it was independent of the position of geminal substitution. Crystallization was primarily governed by the stabilization of high-energy dimer by favorable π-π stacking involving Fmoc moieties. High free-energy of the dimers (γ 2,2 -close, γ 3,3 -open/close) offset favorable stacking interactions and hindered crystallization.
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Affiliation(s)
- Swapna Debnath
- Indian Institute of Technology Guwahati, Department of chemistry, INDIA
| | - Suvankar Ghosh
- Indian Institute of Technology Guwahati, Bioscience and Bioengineering, INDIA
| | - Dinesh Kumar
- CSIR-CIMAP: Central Institute of Medicinal and Aromatic Plants CSIR, Plant Biotechnology Division, INDIA
| | - Prema G Vasudev
- CSIR-CIMAP: Central Institute of Medicinal and Aromatic Plants CSIR, Plant Biotechnology Division, INDIA
| | - Priyadarshi Satpati
- Indian Institute of Technology Guwahati, Bioscience and BIoengineering, INDIA
| | - Sunanda Chatterjee
- Indian Institute of Technology Guwahati, CHEMISTRY, IIT GUWAHATI, 781039, GUWAHATI, INDIA
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5
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An overview on the two recent decades’ study of peptides synthesis and biological activities in Iran. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2022. [DOI: 10.1007/s13738-021-02312-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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6
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Abstract
In this highlight, we describe the construction of supramolecular single/double/triple-helical assemblies from small di/tri/tetrapeptides and their applications.
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Affiliation(s)
- Rajat Subhra Giri
- Department of Chemistry, Laboratory of Peptide and Amyloid Research, Indian Institute of Technology Guwahati, Assam-781039, India
| | - Bhubaneswar Mandal
- Department of Chemistry, Laboratory of Peptide and Amyloid Research, Indian Institute of Technology Guwahati, Assam-781039, India
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7
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Debnath S, Ghosh S, Pandit G, Satpati P, Chatterjee S. Effect of Differential Geminal Substitution of γ Amino Acid Residues at the ( i + 2) Position of αγ Turn Segments on the Conformation of Template β-Hairpin Peptides. J Org Chem 2021; 86:11310-11323. [PMID: 34479402 DOI: 10.1021/acs.joc.1c00351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effect of insertion of three geminally dimethyl substituted γ amino acid residues [γ2,2 (4-amino-2,2-dimethylbutanoic acid), γ3,3 (4-amino-3,3-dimethylbutanoic acid), and γ4,4 (4-amino-4,4-dimethylbutanoic acid)] at the (i + 2) position of a two-residue αγ C12 turn segment in a model octapeptide sequence Leu-Phe-Val-Aib-Xxx-Leu-Phe-Val (where Xxx = γ amino acid residues) has been investigated in this study. Solution conformational studies (NMR, CD, and IR) and ab initio calculations indicated that γ3,3 and γ4,4 residues were well accommodated in the β-hairpin nucleating αγ C12 turns, which gave rise to well-registered hairpins, in contrast to γ2,2, which was unable to form a tight C12 β-hairpin nucleating turn and promote a well-registered β-hairpin. Geminal disubstitution at the Cα carbon in γ2,2 led to unfavorable steric contacts, disabling its accommodation in the αγ C12 hairpin nucleating turn unlike the γ3,3 and γ4,4 residues. Geminal substitutions at different carbons along the backbone constrained backbone torsion angles for the three γ amino acid residues differently, generating diverse conformational preferences in them. Folded hairpins were energetically more stable (∼8 to 9 kcal/mol) than the unfolded peptides. Conformational preference of the peptides was independent of the N-terminal protecting group. Such fundamental understanding will instrumentalize the future directed design of foldamers.
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Affiliation(s)
- Swapna Debnath
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India
| | - Suvankar Ghosh
- Biosciences and Bioengineering Indian Institute of Technology, Guwahati, Assam 781039, India
| | - Gopal Pandit
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India
| | - Priyadarshi Satpati
- Biosciences and Bioengineering Indian Institute of Technology, Guwahati, Assam 781039, India
| | - Sunanda Chatterjee
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India
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8
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Lawer A, Hunter L. Controlling γ‐Peptide Helicity with Stereoselective Fluorination. European J Org Chem 2021. [DOI: 10.1002/ejoc.202001619] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Aggie Lawer
- School of Chemistry The University of New South Wales (UNSW) Sydney 2052 Australia
| | - Luke Hunter
- School of Chemistry The University of New South Wales (UNSW) Sydney 2052 Australia
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9
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Katoh T, Suga H. Development of Bioactive Foldamers Using Ribosomally Synthesized Nonstandard Peptide Libraries. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200326] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Takayuki Katoh
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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10
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Méndez SB, Matus-Ortega M, Miramontes RH, Salazar-Juárez A. Effect of the morphine/heroin vaccine on opioid and non-opioid drug-induced antinociception in mice. Eur J Pharmacol 2021; 891:173718. [PMID: 33171151 DOI: 10.1016/j.ejphar.2020.173718] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 10/29/2020] [Accepted: 10/30/2020] [Indexed: 01/08/2023]
Abstract
Pain is a common symptom in patients with opioid use disorder (OUD), which increases synthetic and illicit synthetic opioid abuse and even fatalities due to opioid overdose. Many FDA-approved drugs are available for the treatment of OUD, however, the use of these medications is limited, mainly due to the development of various side effects. Active vaccination is a new therapeutic approach but the resulting antibodies may compromise the use and efficiency of opioid and non-opioid drugs. In this study, we evaluated whether the antibodies produced by the morphine/heroin vaccine (M-TT) would alter the antinociceptive effects of opioid and non-opioid drugs. Female Balb-c mice were immunized with the M-TT vaccine. A solid-phase antibody-capture ELISA was used for monitoring antibody titer responses after each booster dose in vaccinated animals, followed by tail-flick testing. This study found that the M-TT vaccine did not affect the antinociception induced by different doses of morphine or the ability of non-opioid and synthetic opioid drugs to decrease thermal pain. Moreover, the combination of vaccination and naloxone increased the time-course of morphine antagonism relative to either vaccination or naloxone alone. These results suggest that the antibody titers generated by the M-TT vaccine 1) are capable of reducing morphine-induced antinociception and 2) are selective enough not to alter antinociception induced by non-opioid or synthetic drugs. These characteristics support its potential as a treatment agent for patients with symptoms of pain comorbid to OUD.
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11
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Roy S, Giri RS, Dolai G, Mandal B. Role of side-chain and chirality of the amino acids on the supramolecular assemblies of dipeptides. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128877] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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12
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Shankar S, Junaid Ur Rahim, Rai R. Self-Assembly in Peptides Containing β-and γ-amino Acids. Curr Protein Pept Sci 2020; 21:584-597. [DOI: 10.2174/1389203721666200127112244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/07/2019] [Accepted: 10/07/2019] [Indexed: 12/17/2022]
Abstract
The peptides containing β-and γ-amino acids as building blocks display well-defined secondary
structures with unique morphologies. The ability of such peptides to self-assemble into complex
structures of controlled geometries has been exploited in biomedical applications. Herein, we have
provided an updated overview about the peptides containing β-and γ-amino acids considering the significance
and advancement in the area of development of peptide-based biomaterials having diverse
applications.
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Affiliation(s)
- Sudha Shankar
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu-180001, India
| | - Junaid Ur Rahim
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu-180001, India
| | - Rajkishor Rai
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu-180001, India
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13
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Katoh T, Suga H. Ribosomal Elongation of Cyclic γ-Amino Acids using a Reprogrammed Genetic Code. J Am Chem Soc 2020; 142:4965-4969. [PMID: 32129615 DOI: 10.1021/jacs.9b12280] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Because γ-amino acids generally undergo rapid self-cyclization upon esterification on the carboxyl group, for example, γ-aminoacyl-tRNA, there are no reports of the ribosomal elongation of γ-amino acids to the best of our knowledge. To avoid such self-cyclization, we utilized cyclic γ-amino acids and demonstrated their elongation into a peptide chain. Although the incorporation of the cyclic γ-amino acids is intrinsically slow, we here show that the combination of elongation factor P and engineered tRNAs improves cyclic γ-amino acid incorporation efficiency. Via this method, thioether-macrocyclic peptides containing not only cyclic γ-amino acids but also d-α-, N-methyl-α-, and cyclic β-amino acids were expressed under the reprogrammed genetic code. Ribosomally synthesized macrocyclic peptide libraries containing cyclic γ-amino acids should be applicable to in vitro screening methodologies such as mRNA display for discovering novel peptide drugs.
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Affiliation(s)
- Takayuki Katoh
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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14
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Pregabalin peptides: conformational comparison of γ3- and γ4-substituted γ-amino acids in αγααα pentapeptides. Amino Acids 2019; 51:1297-1306. [DOI: 10.1007/s00726-019-02768-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 08/01/2019] [Indexed: 10/26/2022]
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15
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Misra R, Saseendran A, Dey S, Gopi HN. Metal‐Helix Frameworks from Short Hybrid Peptide Foldamers. Angew Chem Int Ed Engl 2019; 58:2251-2255. [DOI: 10.1002/anie.201810849] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Rajkumar Misra
- Department of ChemistryIndian Institution of Science Education and Research Dr. Homi Bhabha Road Pune- 411008 India
| | - Abhijith Saseendran
- Department of ChemistryIndian Institution of Science Education and Research Dr. Homi Bhabha Road Pune- 411008 India
| | - Sanjit Dey
- Department of ChemistryIndian Institution of Science Education and Research Dr. Homi Bhabha Road Pune- 411008 India
| | - Hosahudya N. Gopi
- Department of ChemistryIndian Institution of Science Education and Research Dr. Homi Bhabha Road Pune- 411008 India
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16
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Misra R, Saseendran A, Dey S, Gopi HN. Metal-Helix Frameworks from Short Hybrid Peptide Foldamers. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201810849] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Rajkumar Misra
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
| | - Abhijith Saseendran
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
| | - Sanjit Dey
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
| | - Hosahudya N. Gopi
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
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17
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González MA, Estévez AM, Campos M, Estévez JC, Estévez RJ. Protocol for the Incorporation of γ-Amino Acids into Peptides: Application to (-)-Shikimic Acid Based 2-Amino-Methylcyclohexanecarboxylic Acids. J Org Chem 2018; 83:1543-1550. [PMID: 29297227 DOI: 10.1021/acs.joc.7b02671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The first example of a new protocol for the incorporation of γ-amino acids into peptides is reported. It involved a shikimic acid based stereoselective synthesis polyhydroxylated-2-nitromethylcyclohexanecarboxylic acids, which were directly incorporated into peptides.
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Affiliation(s)
- Marcos A González
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Campus Vida, Universidade de Santiago de Compostela , 15782 Santiago de Compostela, Spain
| | - Amalia M Estévez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Campus Vida, Universidade de Santiago de Compostela , 15782 Santiago de Compostela, Spain
| | - María Campos
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Campus Vida, Universidade de Santiago de Compostela , 15782 Santiago de Compostela, Spain
| | - Juan C Estévez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Campus Vida, Universidade de Santiago de Compostela , 15782 Santiago de Compostela, Spain
| | - Ramón J Estévez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Campus Vida, Universidade de Santiago de Compostela , 15782 Santiago de Compostela, Spain
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18
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Konda M, Jadhav RG, Maiti S, Mobin SM, Kauffmann B, Das AK. Understanding the conformational analysis of gababutin based hybrid peptides. Org Biomol Chem 2018; 16:1728-1735. [DOI: 10.1039/c8ob00035b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A new class of gababutin-based tetrapeptide shows a C12/C10 hydrogen-bonded hybrid turn.
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Affiliation(s)
- Maruthi Konda
- Department of Chemistry
- Indian Institute of Technology Indore
- Indore 453552
- India
| | - Rohit G. Jadhav
- Department of Chemistry
- Indian Institute of Technology Indore
- Indore 453552
- India
| | - Sayan Maiti
- Department of Chemistry
- Indian Institute of Technology Indore
- Indore 453552
- India
| | - Shaikh M. Mobin
- Department of Chemistry
- Indian Institute of Technology Indore
- Indore 453552
- India
| | - Brice Kauffmann
- Université de Bordeaux
- CNRS
- UMS 3033
- INSERM US001 Institut Européen de Chimie et de Biologie (IECB)
- 33600 Pessac
| | - Apurba K. Das
- Department of Chemistry
- Indian Institute of Technology Indore
- Indore 453552
- India
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19
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Misra R, Raja KMP, Hofmann HJ, Gopi HN. Modulating the Structural Properties of α,γ-Hybrid Peptides by α-Amino Acid Residues: Uniform 12-Helix Versus "Mixed" 12/10-Helix. Chemistry 2017; 23:16644-16652. [PMID: 28922503 DOI: 10.1002/chem.201703871] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Indexed: 01/06/2023]
Abstract
The most important natural α- and 310 -helices are stabilized by unidirectional intramolecular hydrogen bonds along the helical cylinder. In contrast, we report here on 12/10-helical conformations with alternately changing hydrogen-bond directionality in sequences of α,γ-hybrid peptides P1-P5 [P1: Boc-Ala-Aic-Ala-Aic-COOH; P2: Boc-Leu-Aic-Leu-Aic-OEt; P3: Boc-Leu-Aic-Leu-Aic-Leu-Aic-Aib-OMe; P4: Boc-Ala-Aic-Ala-Aic-Ala-Aic-Ala-OMe; P5: Boc-Leu-Aic-Leu-Aic-Leu-Aic-Leu-Aic-Aib-OMe; Aic=4-aminoisocaproic acid, Aib=2-aminoisobutyric acid] composed of natural α-amino acids and the achiral γ4,4 -dimethyl substituted γ-amino acid Aic in solution and in single crystals. The helical conformations are stabilized by alternating i→i+3 and i→i-1 intramolecular hydrogen bonds. The experimental data are supported by ab initio MO calculations. Surprisingly, replacing the natural α-amino acids of the sequence by the achiral dialkyl amino acid Ac6 c [P6: Boc-Ac6 c-Aic-Ac6 c-Aic-Ac6 c-Aic-Ac6 c-Aic-Ac6 c-CONHMe; Ac6 c = 1-aminocyclohexane-1-carboxylic acid] led to a 12-helix with unidirectional hydrogen bonds showing an entirely different backbone conformation. The results presented here emphasize the influence of the structure of the α-amino acid residues in dictating the helix types in α,γ-hybrid peptide foldamers and demonstrate the consequences for folding of small structural variations in the monomers.
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Affiliation(s)
- Rajkumar Misra
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 411 008, India
| | - K Muruga Poopathi Raja
- Department of Physical Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, 625 021, India
| | - Hans-Jörg Hofmann
- Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, Brüderstrasse 34, 04103, Leipzig, Germany
| | - Hosahudya N Gopi
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 411 008, India
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20
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Richard M, Felten AS, Chrétien F, Averlant-Petit MC, Pellegrini-Moïse N. Synthesis and conformational studies of short mixed γ/α-glycopeptides based on sugar γ 3,3 -amino acids. Tetrahedron 2017. [DOI: 10.1016/j.tet.2017.10.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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21
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Ishido Y, Kanbayashi N, Okamura TA, Onitsuka K. Synthesis of Nonnatural Helical Polypeptide via Asymmetric Polymerization and Reductive Cleavage of N–O Bond. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01426] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Yuki Ishido
- Department of Macromolecular
Science Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Naoya Kanbayashi
- Department of Macromolecular
Science Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Taka-aki Okamura
- Department of Macromolecular
Science Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Kiyotaka Onitsuka
- Department of Macromolecular
Science Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
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22
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Jadhav SV, Amabili P, Stammler H, Sewald N. Remarkable Modulation of Self‐Assembly in Short γ‐Peptides by Neighboring Ions and Orthogonal H‐Bonding. Chemistry 2017; 23:10352-10357. [DOI: 10.1002/chem.201701450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Sandip V. Jadhav
- Department of Chemistry, Organic and Bioorganic ChemistryBielefeld University Universitätsstrasse 25 33615 Bielefeld Germany
| | - Paolo Amabili
- Department of Chemistry, Organic and Bioorganic ChemistryBielefeld University Universitätsstrasse 25 33615 Bielefeld Germany
- Department of Life and Environmental SciencesUniversità Politecnica delle Marche Ancona Italy
| | - Hans‐Georg Stammler
- Department of Chemistry, Inorganic ChemistryBielefeld University Universitätsstrasse 25 33615 Bielefeld Germany
| | - Norbert Sewald
- Department of Chemistry, Organic and Bioorganic ChemistryBielefeld University Universitätsstrasse 25 33615 Bielefeld Germany
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23
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Misra R, Saseendran A, George G, Veeresh K, Raja KMP, Raghothama S, Hofmann HJ, Gopi HN. Structural Dimorphism of Achiral α,γ-Hybrid Peptide Foldamers: Coexistence of 12- and 15/17-Helices. Chemistry 2017; 23:3764-3772. [DOI: 10.1002/chem.201605753] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Indexed: 01/17/2023]
Affiliation(s)
- Rajkumar Misra
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
| | - Abhijith Saseendran
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
| | - Gijo George
- NMR Research Center; Indian Institute of Science; Bangalore 560012 India
| | - Kuruva Veeresh
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
| | - K. Muruga Poopathi Raja
- Department of Physical Chemistry; School of Chemistry; Madurai Kamaraj University; Madurai 625 021 India
| | | | - Hans-Jörg Hofmann
- Institute of Biochemistry; Faculty of Biosciences, Pharmacy and Psychology; Talstraße 33 04103 Leipzig Germany
| | - Hosahudya N. Gopi
- Department of Chemistry; Indian Institution of Science Education and Research; Dr. Homi Bhabha Road Pune 411021 India
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24
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Makwana KM, Mahalakshmi R. Capping β-hairpin with N-terminal d-amino acid stabilizes peptide scaffold. Biopolymers 2017; 106:260-6. [PMID: 26999275 DOI: 10.1002/bip.22837] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/08/2016] [Accepted: 03/16/2016] [Indexed: 12/25/2022]
Abstract
Various strategies exist to stabilize de novo designed synthetic peptide β-hairpins or β-sheets structures, especially at the non-hydrogen bonding position. However, strategies to stabilize strand termini, which are affected by fraying, are highly limited. Here, by substituting N-terminal aliphatic amino acid with its mirror image counterpart, we achieve a significant increase in scaffold stabilization, resulting from the formation of a terminal aliphatic-aromatic hydrophobic CH…pi cluster. Our extensive solution NMR studies support the incorporation of an N-terminal d-aliphatic amino acid in the design of short β-hairpins, while successfully retaining the overall structural scaffold. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 260-266, 2016.
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Affiliation(s)
- Kamlesh M Makwana
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, Madhya Pradesh, India
| | - Radhakrishnan Mahalakshmi
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, Madhya Pradesh, India
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25
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Malik A, Kumar MG, Bandyopadhyay A, Gopi HN. Helices with additional H-bonds: crystallographic conformations of α,γ-hybrid peptides helices composed of β-hydroxy γ-amino acids (statines). Biopolymers 2017; 108. [DOI: 10.1002/bip.22978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 08/05/2016] [Accepted: 08/25/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Ankita Malik
- Department of Chemistry; Indian Institute of Science Education and Research-Pune; Dr. Homi Bhabha Road Pune 411008 India
| | - Mothukuri Ganesh Kumar
- Department of Chemistry; Indian Institute of Science Education and Research-Pune; Dr. Homi Bhabha Road Pune 411008 India
| | - Anupam Bandyopadhyay
- Department of Chemistry; Indian Institute of Science Education and Research-Pune; Dr. Homi Bhabha Road Pune 411008 India
| | - Hosahudya N. Gopi
- Department of Chemistry; Indian Institute of Science Education and Research-Pune; Dr. Homi Bhabha Road Pune 411008 India
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26
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Hekmat S, Balalaie S, Ramezanpour S, Rominger F, Vavsari VF, Kabiri-Fard H. SBA-Pr-SO3H: an efficient catalyst for the combinatorial synthesis of functionalized 2-aryl-4-quinazolinones using unusual γ-amino acids. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2016. [DOI: 10.1007/s13738-016-1033-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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27
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Ordóñez M, Cativiela C, Romero-Estudillo I. An update on the stereoselective synthesis of γ-amino acids. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.tetasy.2016.08.011] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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28
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Romero E, Moussodia RO, Kriznik A, Wenger E, Acherar S, Jamart-Grégoire B. Spontaneous Self-Assembly of Fully Protected Ester 1:1 [α/α-N α-Bn-hydrazino] Pseudodipeptides into a Twisted Parallel β-Sheet in the Crystal State. J Org Chem 2016; 81:9037-9045. [PMID: 27627436 DOI: 10.1021/acs.joc.6b01680] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Previous studies have demonstrated that amidic α/β-pseudodipeptides, 1:1 [α/α-Nα-Bn-hydrazino], have the ability to fold via a succession of γ-turn (C7 pseudocycle) and hydrazinoturn in CDCl3 solution, their amide terminals enabling the formation of an intramolecular H-bond network. Despite their lack of a primary amide terminals allowing the formation of the hydrazinoturn, their ester counterparts 1-4 were proven to self-assemble into C6 and C7 pseudocycles by intramolecular H-bonds in solution state and into an uncommon twisted parallel β-sheet through intermolecular H-bonding in the crystal state to form a supramolecular helix, with eight molecules needed to complete a full 360° rotation. Such self-organization (with eight molecules) has only been observed in a specific α/α-pseudodipeptide, depsipeptide (Boc-Leu-Lac-OEt). Relying on IR absorption, NMR, X-ray diffraction, and CD analyses, the aim of this study was to demonstrate that stereoisomers of ester 1:1 [α/α-Nα-Bn-hydrazino] pseudodipeptides 1-4 are able to self-assemble into this β-helical structure. The absolute configuration of the asymmetric Cα-atom of the α-amino acid residue influences the left- or right-handed twist without changing the pitch of the formed helix.
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Affiliation(s)
- Eugénie Romero
- Laboratoire de Chimie Physique Macromoléculaire (LCPM), Université de Lorraine-CNRS, UMR 7375 , 1 rue Grandville, BP 20451, 54001 Nancy cedex, France
| | - Ralph-Olivier Moussodia
- Laboratoire de Chimie Physique Macromoléculaire (LCPM), Université de Lorraine-CNRS, UMR 7375 , 1 rue Grandville, BP 20451, 54001 Nancy cedex, France
| | - Alexandre Kriznik
- Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), Université de Lorraine-CNRS, UMR 7365 and Service Commun de Biophysique Interactions Moléculaires (SCBIM), Université de Lorraine, FR3209, Biopôle de l'Université de Lorraine, Campus Biologie Santé - Faculté de Médecine , 9 Avenue de la Forêt de Haye, CS 50184, 54505 Vandœuvre-lès-Nancy, France
| | - Emmanuel Wenger
- Laboratoire de Crystallographie, Résonance Magnétique et Modélisations (CRM2), Université de Lorraine-CNRS, UMR 7036, Faculté des Sciences et Technologies , BP 70239, Boulevard des Aiguillettes, 54506 Vandœuvre-lès-Nancy cedex, France
| | - Samir Acherar
- Laboratoire de Chimie Physique Macromoléculaire (LCPM), Université de Lorraine-CNRS, UMR 7375 , 1 rue Grandville, BP 20451, 54001 Nancy cedex, France
| | - Brigitte Jamart-Grégoire
- Laboratoire de Chimie Physique Macromoléculaire (LCPM), Université de Lorraine-CNRS, UMR 7375 , 1 rue Grandville, BP 20451, 54001 Nancy cedex, France
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29
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Shankar S, Wani NA, Singh UP, Rai R. Incipient Twisted Ribbon Structure Stabilized by C12Helical Turns in γ4/α Hybrid Peptide. ChemistrySelect 2016. [DOI: 10.1002/slct.201600793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Sudha Shankar
- Medicinal Chemistry Division; CSIR-Indian Institute of Integrative Medicine; Canal Road Jammu Tawi- 180001 India
- Academy of Scientific and Innovative Research; New Delhi India
| | - Naiem Ahmad Wani
- Medicinal Chemistry Division; CSIR-Indian Institute of Integrative Medicine; Canal Road Jammu Tawi- 180001 India
| | - Umesh Prasad Singh
- CSIR-Indian Institute of Chemical Biology; 4, Raja, S.C. Mullick Road Kolkata- 700032 India
| | - Rajkishor Rai
- Medicinal Chemistry Division; CSIR-Indian Institute of Integrative Medicine; Canal Road Jammu Tawi- 180001 India
- Academy of Scientific and Innovative Research; New Delhi India
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30
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Fisher BF, Gellman SH. Impact of γ-Amino Acid Residue Preorganization on α/γ-Peptide Foldamer Helicity in Aqueous Solution. J Am Chem Soc 2016; 138:10766-9. [PMID: 27529788 DOI: 10.1021/jacs.6b06177] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
α/γ-Peptide foldamers containing either γ(4)-amino acid residues or ring-constrained γ-amino acid residues have been reported to adopt 12-helical secondary structure in nonpolar solvents and in the solid state. These observations have engendered speculation that the seemingly flexible γ(4) residues have a high intrinsic helical propensity and that residue-based preorganization may not significantly stabilize the 12-helical conformation. However, the prior studies were conducted in environments that favor intramolecular H-bond formation. Here, we use 2D-NMR to compare the ability of γ(4) residues and cyclic γ residues to support 12-helix formation in more challenging environments, methanol and water. Both γ residue types support 12-helical folding in methanol, but only the cyclically constrained γ residues promote helicity in water. These results demonstrate the importance of residue-based preorganization strategies for achieving stable folding among short foldamers in aqueous solution.
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Affiliation(s)
- Brian F Fisher
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Samuel H Gellman
- Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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31
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Ganesh Kumar M, Thombare VJ, Katariya MM, Veeresh K, Raja KMP, Gopi HN. Non-classical Helices withcisCarbon-Carbon Double Bonds in the Backbone: Structural Features of α,γ-Hybrid Peptide Foldamers. Angew Chem Int Ed Engl 2016; 55:7847-51. [DOI: 10.1002/anie.201602861] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Mothukuri Ganesh Kumar
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - Varsha J. Thombare
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - Mona M. Katariya
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - Kuruva Veeresh
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - K. Muruga Poopathi Raja
- Department of Physical Chemistry; School of Chemistry; Madurai Kamaraj University; Madurai- 625 021 India
| | - Hosahudya N. Gopi
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
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32
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Ganesh Kumar M, Thombare VJ, Katariya MM, Veeresh K, Raja KMP, Gopi HN. Non-classical Helices withcisCarbon-Carbon Double Bonds in the Backbone: Structural Features of α,γ-Hybrid Peptide Foldamers. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201602861] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Mothukuri Ganesh Kumar
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - Varsha J. Thombare
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - Mona M. Katariya
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - Kuruva Veeresh
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
| | - K. Muruga Poopathi Raja
- Department of Physical Chemistry; School of Chemistry; Madurai Kamaraj University; Madurai- 625 021 India
| | - Hosahudya N. Gopi
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road, Pashan Pune- 411008 India
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33
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Wani NA, Gupta VK, Singh UP, Aravinda S, Rai R. Folded Structure Stabilized by C 7, C 10and C 12Hydrogen Bonds in αγ Hybrid Peptides. ChemistrySelect 2016. [DOI: 10.1002/slct.201600389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Naiem Ahmad Wani
- Medicinal Chemistry Division; Indian Institute of Integrative Medicine; Canal Road, Jammu- 180001 India
| | - Vivek Kumar Gupta
- X-ray Crystallography Laboratory; Post-Graduate Department of Physics and Electronics; University of Jammu; Jammu Tawi 180 006 India
| | - Umesh Prasad Singh
- CSIR-Indian Institute of Chemical Biology; 4, Raja, S.C. Mullick Road Kolkata- 700032 India
| | - Subrayashastry Aravinda
- Medicinal Chemistry Division; Indian Institute of Integrative Medicine; Canal Road, Jammu- 180001 India
| | - Rajkishor Rai
- Medicinal Chemistry Division; Indian Institute of Integrative Medicine; Canal Road, Jammu- 180001 India
- Academy of Scientific and Innovative Research; New Delhi India
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34
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Wani NA, Kant R, Gupta VK, Aravinda S, Rai R. Ribbon structure stabilized by C10
and C12
turns in αγ
hybrid peptide. J Pept Sci 2016; 22:208-13. [DOI: 10.1002/psc.2864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/23/2016] [Accepted: 01/25/2016] [Indexed: 01/03/2023]
Affiliation(s)
- Naiem Ahmad Wani
- Medicinal Chemistry Division; Indian Institute of Integrative Medicine; Canal Road Jammu Tawi 180001 India
| | - Rajni Kant
- X-ray Crystallography Laboratory, Post-Graduate Department of Physics and Electronics; University of Jammu; Jammu Tawi 180 006 India
| | - Vivek Kumar Gupta
- X-ray Crystallography Laboratory, Post-Graduate Department of Physics and Electronics; University of Jammu; Jammu Tawi 180 006 India
| | - Subrayashastry Aravinda
- Medicinal Chemistry Division; Indian Institute of Integrative Medicine; Canal Road Jammu Tawi 180001 India
| | - Rajkishor Rai
- Medicinal Chemistry Division; Indian Institute of Integrative Medicine; Canal Road Jammu Tawi 180001 India
- Academy of Scientific and Innovative Research; New Delhi India
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35
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Ganesh Kumar M, Gopi HN. γ- and β-Peptide Foldamers from Common Multifaceted Building Blocks: Synthesis and Structural Characterization. Org Lett 2015; 17:4738-41. [DOI: 10.1021/acs.orglett.5b02263] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mothukuri Ganesh Kumar
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, India
| | - Hosahudya N. Gopi
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, India
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36
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Ramanaiah S, Karde V, Venkateswarlu P, Ghoroi C. Effect of temperature on the surface free energy and acid–base properties of Gabapentin and Pregabalin drugs − a comparative study. RSC Adv 2015. [DOI: 10.1039/c5ra03032c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Temperature dependent surface energy variations observed in Gabapentin and Pregabalin drugs.
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Affiliation(s)
- S. Ramanaiah
- Department of Chemistry
- Sri Venkateswara University
- Tirupati-517502
- India
| | - Vikram Karde
- DryProTech Lab
- Chemical Engineering
- Indian Institute of Technology Gandhinagar
- Ahmedabad-382424
- India
| | - P. Venkateswarlu
- Department of Chemistry
- Sri Venkateswara University
- Tirupati-517502
- India
| | - Chinmay Ghoroi
- DryProTech Lab
- Chemical Engineering
- Indian Institute of Technology Gandhinagar
- Ahmedabad-382424
- India
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37
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Giuliano MW, Maynard SJ, Almeida AM, Guo L, Guzei IA, Spencer LC, Gellman SH. A γ-Amino Acid That Favors 12/10-Helical Secondary Structure in α/γ-Peptides. J Am Chem Soc 2014; 136:15046-53. [DOI: 10.1021/ja5076585] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael W. Giuliano
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Stacy J. Maynard
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Aaron M. Almeida
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Li Guo
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Ilia A. Guzei
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Lara C. Spencer
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Samuel H. Gellman
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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38
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Wani NA, Gupta VK, Kant R, Aravinda S, Rai R. An unusual conformation of gabapentin (Gpn) in Pyr-Gpn-NH-NH-Pyr stabilized by weak interactions. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2014; 70:776-9. [PMID: 25093358 DOI: 10.1107/s2053229614015587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 07/03/2014] [Indexed: 11/10/2022]
Abstract
The crystal structure of N-[(1-{2-oxo-2-[2-(pyrazin-2-ylcarbonyl)hydrazin-1-yl]ethyl}cyclohexyl)methyl]pyrazine-2-carboxamide monohydrate (Pyr-Gpn-NN-NH-Pyr·H2O), C19H23N7O3·H2O, reveals an unusual trans-gauche (tg(-)) conformation for the gabapentin (Gpn) residue around the C(γ)-C(β) (θ1) and C(β)-C(α) (θ2) bonds. The molecular conformation is stabilized by intramolecular N-H...N hydrogen bonds and weak C-H...O interactions. The packing of the molecules in the crystal lattice shows a network of strong N-H...O and O-H...O hydrogen bonds together with weak C-H...O and π-π inteactions.
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Affiliation(s)
- Naiem Ahmad Wani
- Medicinal Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi 180 001, India
| | - Vivek Kumar Gupta
- X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics, University of Jammu, Jammu Tawi 180 006, India
| | - Rajni Kant
- X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics, University of Jammu, Jammu Tawi 180 006, India
| | - Subrayashastry Aravinda
- Medicinal Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi 180 001, India
| | - Rajkishor Rai
- Medicinal Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi 180 001, India
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39
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Kang Q, Wang L, Zheng Z, Li J, Tang Y. Sidearm as a Control in the Asymmetric Ring Opening Reaction of Donor-Acceptor Cyclopropane. CHINESE J CHEM 2014. [DOI: 10.1002/cjoc.201400053] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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40
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Krishna Y, Sharma S, Ampapathi RS, Koley D. Furan-Based Locked Z-Vinylogous γ-Amino Acid Stabilizing Protein α-Turn in Water-Soluble Cyclic α3γ Tetrapeptides. Org Lett 2014; 16:2084-7. [DOI: 10.1021/ol5002126] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yarkali Krishna
- Medicinal and Process Chemistry
Division and ‡Centre for Nuclear Magnetic Resonance,
SAIF, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh 226031, India
| | - Shrikant Sharma
- Medicinal and Process Chemistry
Division and ‡Centre for Nuclear Magnetic Resonance,
SAIF, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh 226031, India
| | - Ravi S. Ampapathi
- Medicinal and Process Chemistry
Division and ‡Centre for Nuclear Magnetic Resonance,
SAIF, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh 226031, India
| | - Dipankar Koley
- Medicinal and Process Chemistry
Division and ‡Centre for Nuclear Magnetic Resonance,
SAIF, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh 226031, India
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41
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Gord JR, Walsh PS, Fisher BF, Gellman SH, Zwier TS. Mimicking the First Turn of an α-Helix with an Unnatural Backbone: Conformation-Specific IR and UV Spectroscopy of Cyclically Constrained β/γ-Peptides. J Phys Chem B 2014; 118:8246-56. [PMID: 24694352 DOI: 10.1021/jp5015884] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Joseph R. Gord
- Department
of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
| | - Patrick S. Walsh
- Department
of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
| | - Brian F. Fisher
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Samuel H. Gellman
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Timothy S. Zwier
- Department
of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
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42
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Sonti R, Dinesh B, Basuroy K, Raghothama S, Shamala N, Balaram P. C12 helices in long hybrid (αγ)n peptides composed entirely of unconstrained residues with proteinogenic side chains. Org Lett 2014; 16:1656-9. [PMID: 24588077 DOI: 10.1021/ol500307p] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Unconstrained γ(4) amino acid residues derived by homologation of proteinogenic amino acids facilitate helical folding in hybrid (αγ)n sequences. The C12 helical conformation for the decapeptide, Boc-[Leu-γ(4)(R)Val]5-OMe, is established in crystals by X-ray diffraction. A regular C12 helix is demonstrated by NMR studies of the 18 residue peptide, Boc-[Leu-γ(4)(R)Val]9-OMe, and a designed 16 residue (αγ)n peptide, incorporating variable side chains. Unconstrained (αγ)n peptides show an unexpectedly high propensity for helical folding in long polypeptide sequences.
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Affiliation(s)
- Rajesh Sonti
- Molecular
Biophysics Unit, Indian Institute of Science, Bangalore, India, 560012
- NMR
Research Centre, Indian Institute of Science, Bangalore, India, 560012
| | - Bhimareddy Dinesh
- Molecular
Biophysics Unit, Indian Institute of Science, Bangalore, India, 560012
| | - Krishnayan Basuroy
- Department
of Physics, Indian Institute of Science, Bangalore, India, 560012
| | | | | | - Padmanabhan Balaram
- Molecular
Biophysics Unit, Indian Institute of Science, Bangalore, India, 560012
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43
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Gabapentin hybrid peptides and bioconjugates. Bioorg Med Chem 2014; 22:1479-86. [DOI: 10.1016/j.bmc.2013.12.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 11/27/2013] [Accepted: 12/06/2013] [Indexed: 11/17/2022]
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44
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Wani NA, Gupta VK, Kant R, Aravinda S, Rai R. Conformation of a terminally protected βγ hybrid dipeptide Boc-Ant-Gpn-OMe stabilized by C6/C7 hydrogen bonds. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2014; 70:46-9. [PMID: 24399225 DOI: 10.1107/s2053229613033044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 12/06/2013] [Indexed: 11/11/2022]
Abstract
The hybrid βγ dipeptide, methyl 2-[1-({2-[(tert-butoxycarbonyl)amino]benzamido}methyl)cyclohexyl]acetate (Boc-Ant-Gpn-OMe), C22H32N2O5, adopts a folded conformation stabilized by intramolecular six- (C6) and seven-membered (C7) hydrogen-bonded rings, together with weak C-H...O and C-H...π interactions, resulting in a ribbon-like structure.
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Affiliation(s)
- Naiem Ahmad Wani
- Medicinal Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi 180 001, India
| | - Vivek Kumar Gupta
- X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics, University of Jammu, Jammu Tawi 180 006, India
| | - Rajni Kant
- X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics, University of Jammu, Jammu Tawi 180 006, India
| | - Subrayashastry Aravinda
- Medicinal Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi 180 001, India
| | - Rajkishor Rai
- Medicinal Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi 180 001, India
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45
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Roy A, Kotmale AS, Gawade RL, Puranik VG, Rajamohanan PR, Sanjayan GJ. Probing the folding induction ability of orthanilic acid in peptides: some observations. RSC Adv 2014. [DOI: 10.1039/c3ra47039c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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46
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Wang JL, Xu JS, Wang DY, Wang H, Li ZT, Zhang DW. Anti-parallel sheet structures of side-chain-free γ-, δ-, and ε-dipeptides stabilized by benzene–pentafluorobenzene stacking. CrystEngComm 2014. [DOI: 10.1039/c3ce42060d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Benzene–pentafluorobenzene stacking can guide ω-amino acid dipeptides to arrange in an anti-parallel manner.
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Affiliation(s)
- Ji-Liang Wang
- Department of Chemistry
- Fudan University
- Shanghai 200433, China
| | - Jia-Su Xu
- Department of Chemistry
- Fudan University
- Shanghai 200433, China
| | - Dong-Yun Wang
- Department of Chemistry
- Fudan University
- Shanghai 200433, China
| | - Hui Wang
- Department of Chemistry
- Fudan University
- Shanghai 200433, China
| | - Zhan-Ting Li
- Department of Chemistry
- Fudan University
- Shanghai 200433, China
| | - Dan-Wei Zhang
- Department of Chemistry
- Fudan University
- Shanghai 200433, China
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47
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Giuliano MW, Maynard SJ, Almeida AM, Reidenbach AG, Guo L, Ulrich EC, Guzei IA, Gellman SH. Evaluation of a cyclopentane-based γ-amino acid for the ability to promote α/γ-peptide secondary structure. J Org Chem 2013; 78:12351-61. [PMID: 24303945 PMCID: PMC4109159 DOI: 10.1021/jo401501g] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We report the asymmetric synthesis of the γ-amino acid (1R,2R)-2-aminomethyl-1-cyclopentane carboxylic acid (AMCP) and an evaluation of this residue's potential to promote secondary structure in α/γ-peptides. Simulated annealing calculations using NMR-derived distance restraints obtained for α/γ-peptides in chloroform reveal that AMCP-containing oligomers are conformationally flexible. However, additional evidence suggests that an internally hydrogen-bonded helical conformation is partially populated in solution. From these data, we propose characteristic NOE patterns for the formation of the α/γ-peptide 12/10-helix and discuss the apparent conformational frustration of AMCP-containing oligomers.
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Affiliation(s)
| | - Stacy J. Maynard
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Aaron M. Almeida
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Andrew G. Reidenbach
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Li Guo
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Emily C. Ulrich
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Ilia A. Guzei
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Samuel H. Gellman
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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48
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Bandyopadhyay A, Malik A, Kumar MG, Gopi HN. Exploring β-Hydroxy γ-Amino Acids (Statines) in the Design of Hybrid Peptide Foldamers. Org Lett 2013; 16:294-7. [DOI: 10.1021/ol403290h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Anupam Bandyopadhyay
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune-411 008, India
| | - Ankita Malik
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune-411 008, India
| | - Mothukuri Ganesh Kumar
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune-411 008, India
| | - Hosahudya N. Gopi
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune-411 008, India
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49
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Nelli YR, Fischer L, Collie GW, Kauffmann B, Guichard G. Structural characterization of short hybrid urea/carbamate (U/C) foldamers: A case of partial helix unwinding. Biopolymers 2013; 100:687-97. [DOI: 10.1002/bip.22302] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 05/21/2013] [Accepted: 05/28/2013] [Indexed: 12/31/2022]
Affiliation(s)
- Yella Reddy Nelli
- Université de Bordeaux, CNRS UMR 5248; CBMN, Institut Européen de Chimie et Biologie; 2 rue Robert Escarpit 33607 Pessac France
| | - Lucile Fischer
- Université de Bordeaux, CNRS UMR 5248; CBMN, Institut Européen de Chimie et Biologie; 2 rue Robert Escarpit 33607 Pessac France
| | - Gavin W. Collie
- Université de Bordeaux, CNRS UMR 5248; CBMN, Institut Européen de Chimie et Biologie; 2 rue Robert Escarpit 33607 Pessac France
| | - Brice Kauffmann
- Université de Bordeaux, CNRS UMS 3033; INSERM US001, Institut Européen de Chimie et Biologie; 2 rue Robert Escarpit 33607 Pessac France
| | - Gilles Guichard
- Université de Bordeaux, CNRS UMR 5248; CBMN, Institut Européen de Chimie et Biologie; 2 rue Robert Escarpit 33607 Pessac France
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50
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Walsh PS, Kusaka R, Buchanan EG, James WH, Fisher BF, Gellman SH, Zwier TS. Cyclic constraints on conformational flexibility in γ-peptides: conformation specific IR and UV spectroscopy. J Phys Chem A 2013; 117:12350-62. [PMID: 24147873 DOI: 10.1021/jp408736t] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Single-conformation spectroscopy has been used to study two cyclically constrained and capped γ-peptides: Ac-γACHC-NHBn (hereafter γACHC, Figure 1a), and Ac-γACHC-γACHC-NHBn (γγACHC, Figure 1b), under jet-cooled conditions in the gas phase. The γ-peptide backbone in both molecules contains a cyclohexane ring incorporated across each Cβ-Cγ bond and an ethyl group at each Cα. This substitution pattern was designed to stabilize a (g+, g+) torsion angle sequence across the Cα-Cβ-Cγ segment of each γ-amino acid residue. Resonant two-photon ionization (R2PI), infrared-ultraviolet hole-burning (IR-UV HB), and resonant ion-dip infrared (RIDIR) spectroscopy have been used to probe the single-conformation spectroscopy of these molecules. In both γACHC and γγACHC, all population is funneled into a single conformation. With RIDIR spectra in the NH stretch (3200-3500 cm(-1)) and amide I/II regions (1400-1800 cm(-1)), in conjunction with theoretical predictions, assignments have been made for the conformations observed in the molecular beam. γACHC forms a single nearest-neighbor C9 hydrogen-bonded ring whereas γγACHC takes up a next-nearest-neighbor C14 hydrogen-bonded structure. The gas-phase C14 conformation represents the beginning of a 2.614-helix, suggesting that the constraints imposed on the γ-peptide backbone by the ACHC and ethyl groups already impose this preference in the gas-phase di-γ-peptide, in which only a single C14 H-bond is possible, constituting one full turn of the helix. A similar conformational preference was previously documented in crystal structures and NMR analysis of longer γ-peptide oligomers containing the γACHC subunit [Guo, L., et al. Angew. Chem. Int. Ed. 2011, 50, 5843-5846]. In the gas phase, the γACHC-H2O complex was also observed and spectroscopically interrogated in the molecular beam. Here, the monosolvated γACHC retains the C9 hydrogen bond observed in the bare molecule, with the water acting as a bridge between the C-terminal carbonyl and the π-cloud of the UV chromophore. This is in contrast to the unconstrained γ-peptide-H2O complex, which incorporates H2O into both C9 and amide-stacked conformations.
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Affiliation(s)
- Patrick S Walsh
- Department of Chemistry, Purdue University , 560 Oval Drive, West Lafayette, Indiana 47907 United States
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