1
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Sukumar G, Rahul, Nayani K, Mainkar PS, Prashanth J, Sridhar B, Sarma AVS, Bharatam J, Chandrasekhar S. 6-Strand to Stable 10/12 Helix Conformational Switch by Incorporating Flexible β-hGly in the Homooligomers of Camphor Derived β-Amino Acid: NMR and X-Ray Crystallographic Evidence. Angew Chem Int Ed Engl 2024; 63:e202403321. [PMID: 38482551 DOI: 10.1002/anie.202403321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Indexed: 04/07/2024]
Abstract
Rational design of unnatural amino acid building blocks capable of stabilizing predictable secondary structures similar to protein fragments is pivotal for foldamer chemistry/catalysis. Here, we introduce novel β-amino acid building blocks: [1S,2R,4R]exoCDA and [1S,2S,4R]endoCDA, derived from the abundantly available R(+)-camphor, which is traditionally known for its medicinal value. Further, we demonstrate that the homooligomers of exoCDA adopt 6-strand conformation, which switches to a robust 10/12-helix simply by inserting flexible β-hGly spacer at alternate positions (1 : 1 β-hGly/exoCDA heterooligomers), as evident by DFT-calculations, solution-state NMR spectroscopy and X-ray crystallography. To the best of our knowledge, this is the first example of crystalline-state structure of left-handed 10/12-mixed helix, that is free from the conventional approach of employing β-amino acids of either alternate chirality or alternate β2/β3 substitutions, to access the 10/12-helix. The results also show that the homooligomers of heterochiral exoCDA don't adopt helical fold, instead exhibit banana-shaped strands, whereas the homodimers of the other diastereomer endoCDA, nucleate 8-membered turns. Furthermore, the homo-exoCDA and hetero-[β-hGly-exoCDA] oligomers are found to exhibit self-association properties with distinct morphological features. Overall, the results offer new possibilties of constructing discrete stable secondary and tertiary structures based on CDAs, which can accommodate flexible residues with desired side-chain substitutions.
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Affiliation(s)
- Genji Sukumar
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Department of Chemistry, Adikavi Nannaya University, Rajamahendravaram, Andhra Pradesh, 533296, India
| | - Rahul
- Centre for NMR, Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Kiranmai Nayani
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Prathama S Mainkar
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Jupally Prashanth
- Centre for X-ray Crystallography, Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Balasubramanian Sridhar
- Centre for X-ray Crystallography, Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Akella V S Sarma
- Centre for NMR, Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Jagadeesh Bharatam
- Centre for NMR, Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Srivari Chandrasekhar
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
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2
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Just D, Palivec V, Bártová K, Bednárová L, Pazderková M, Císařová I, Martinez-Seara H, Jahn U. Foldamers controlled by functional triamino acids: structural investigation of α/γ-hybrid oligopeptides. Commun Chem 2024; 7:114. [PMID: 38796536 PMCID: PMC11128005 DOI: 10.1038/s42004-024-01201-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 05/14/2024] [Indexed: 05/28/2024] Open
Abstract
Peptide-like foldamers controlled by normal amide backbone hydrogen bonding have been extensively studied, and their folding patterns largely rely on configurational and conformational constraints induced by the steric properties of backbone substituents at appropriate positions. In contrast, opportunities to influence peptide secondary structure by functional groups forming individual hydrogen bond networks have not received much attention. Here, peptide-like foldamers consisting of alternating α,β,γ-triamino acids 3-amino-4-(aminomethyl)-2-methylpyrrolidine-3-carboxylate (AAMP) and natural amino acids glycine and alanine are reported, which were obtained by solution phase peptide synthesis. They form ordered secondary structures, which are dominated by a three-dimensional bridged triazaspiranoid-like hydrogen bond network involving the non-backbone amino groups, the backbone amide hydrogen bonds, and the relative configuration of the α,β,γ-triamino and α-amino acid building blocks. This additional stabilization leads to folding in both nonpolar organic as well as in aqueous environments. The three-dimensional arrangement of the individual foldamers is supported by X-ray crystallography, NMR spectroscopy, chiroptical methods, and molecular dynamics simulations.
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Affiliation(s)
- David Just
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Vladimír Palivec
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Kateřina Bártová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Lucie Bednárová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Markéta Pazderková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, 12843, Prague 2, Czech Republic
| | - Hector Martinez-Seara
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic.
| | - Ullrich Jahn
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic.
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3
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Guerinot C, Malige M, Charbonnel N, Malosse K, Jouffret L, Taillefumier C, Roy O, Forestier C, Faure S. Design of Triazolium-Grafted Peptidomimetic Macrocycles with Facial Amphipathicity to Target Pathogenic Bacteria. Org Lett 2024; 26:4088-4092. [PMID: 38709636 DOI: 10.1021/acs.orglett.4c01149] [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: 05/08/2024]
Abstract
Access to 1,2,3-triazolium-grafted peptoid macrocycles was developed by macrocyclization and multivalent postmodification of linear peptoid oligomers carrying an alternance of benzylic and propargyl groups as side chains. X-ray analysis and NMR studies revealed a conformational preference for constrained hairpin-shaped structures leading to the facial amphipathic character of these macrocycles. A preliminary evaluation showed the antimicrobial activities of these new cationic amphipathic architectures.
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Affiliation(s)
- Cassandra Guerinot
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, ICCF, F-63000 Clermont-Ferrand, France
| | - Mélodie Malige
- Université Clermont Auvergne, CNRS, LMGE, F-63000 Clermont-Ferrand, France
| | - Nicolas Charbonnel
- Université Clermont Auvergne, CNRS, LMGE, F-63000 Clermont-Ferrand, France
| | - Killian Malosse
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, ICCF, F-63000 Clermont-Ferrand, France
| | - Laurent Jouffret
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, ICCF, F-63000 Clermont-Ferrand, France
| | - Claude Taillefumier
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, ICCF, F-63000 Clermont-Ferrand, France
| | - Olivier Roy
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, ICCF, F-63000 Clermont-Ferrand, France
| | | | - Sophie Faure
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, ICCF, F-63000 Clermont-Ferrand, France
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4
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Simonyan H, Palumbo R, Petrosyan S, Mkrtchyan A, Galstyan A, Saghyan A, Scognamiglio PL, Vicidomini C, Fik-Jaskólka M, Roviello GN. BSA Binding and Aggregate Formation of a Synthetic Amino Acid with Potential for Promoting Fibroblast Proliferation: An In Silico, CD Spectroscopic, DLS, and Cellular Study. Biomolecules 2024; 14:579. [PMID: 38785986 PMCID: PMC11118884 DOI: 10.3390/biom14050579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/10/2024] [Accepted: 05/11/2024] [Indexed: 05/25/2024] Open
Abstract
This study presents the chemical synthesis, purification, and characterization of a novel non-natural synthetic amino acid. The compound was synthesized in solution, purified, and characterized using NMR spectroscopy, polarimetry, and melting point determination. Dynamic Light Scattering (DLS) analysis demonstrated its ability to form aggregates with an average size of 391 nm, extending to the low micrometric size range. Furthermore, cellular biological assays revealed its ability to enhance fibroblast cell growth, highlighting its potential for tissue regenerative applications. Circular dichroism (CD) spectroscopy showed the ability of the synthetic amino acid to bind serum albumins (using bovine serum albumin (BSA) as a model), and CD deconvolution provided insights into the changes in the secondary structures of BSA upon interaction with the amino acid ligand. Additionally, molecular docking using HDOCK software elucidated the most likely binding mode of the ligand inside the BSA structure. We also performed in silico oligomerization of the synthetic compound in order to obtain a model of aggregate to investigate computationally. In more detail, the dimer formation achieved by molecular self-docking showed two distinct poses, corresponding to the lowest and comparable energies, with one pose exhibiting a quasi-coplanar arrangement characterized by a close alignment of two aromatic rings from the synthetic amino acids within the dimer, suggesting the presence of π-π stacking interactions. In contrast, the second pose displayed a non-coplanar configuration, with the aromatic rings oriented in a staggered arrangement, indicating distinct modes of interaction. Both poses were further utilized in the self-docking procedure. Notably, iterative molecular docking of amino acid structures resulted in the formation of higher-order aggregates, with a model of a 512-mer aggregate obtained through self-docking procedures. This model of aggregate presented a cavity capable of hosting therapeutic cargoes and biomolecules, rendering it a potential scaffold for cell adhesion and growth in tissue regenerative applications. Overall, our findings highlight the potential of this synthetic amino acid for tissue regenerative therapeutics and provide valuable insights into its molecular interactions and aggregation behavior.
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Affiliation(s)
- Hayarpi Simonyan
- Institute of Pharmacy, Yerevan State University, 1 Alex Manoogian Str., Yerevan 0025, Armenia
| | - Rosanna Palumbo
- Institute of Biostructures and Bioimaging, Italian National Council for Research (IBB-CNR), Area di Ricerca Site and Headquarters, Via Pietro Castellino 111, 80131 Naples, Italy
| | - Satenik Petrosyan
- Institute of Pharmacy, Yerevan State University, 1 Alex Manoogian Str., Yerevan 0025, Armenia
| | - Anna Mkrtchyan
- Institute of Pharmacy, Yerevan State University, 1 Alex Manoogian Str., Yerevan 0025, Armenia
| | - Armen Galstyan
- Department of Chemistry, Yerevan State University, 1 Alex Manoogian Str., Yerevan 0025, Armenia
| | - Ashot Saghyan
- Institute of Pharmacy, Yerevan State University, 1 Alex Manoogian Str., Yerevan 0025, Armenia
| | | | - Caterina Vicidomini
- Institute of Biostructures and Bioimaging, Italian National Council for Research (IBB-CNR), Area di Ricerca Site and Headquarters, Via Pietro Castellino 111, 80131 Naples, Italy
| | - Marta Fik-Jaskólka
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
| | - Giovanni N. Roviello
- Institute of Biostructures and Bioimaging, Italian National Council for Research (IBB-CNR), Area di Ricerca Site and Headquarters, Via Pietro Castellino 111, 80131 Naples, Italy
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5
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Bui Thi Phuong H, Doan Ngan H, Le Huy B, Vu Dinh H, Luong Xuan H. The amphipathic design in helical antimicrobial peptides. ChemMedChem 2024; 19:e202300480. [PMID: 38408263 DOI: 10.1002/cmdc.202300480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 12/18/2023] [Indexed: 02/28/2024]
Abstract
Amphipathicity is a critical characteristic of helical antimicrobial peptides (AMPs). The hydrophilic region, primarily composed of cationic residues, plays a pivotal role in the initial binding to negatively charged components on bacterial membranes through electrostatic interactions. Subsequently, the hydrophobic region interacts with hydrophobic components, inducing membrane perturbation, ultimately leading to cell death, or inhibiting intracellular function. Due to the extensive diversity of natural and synthetic AMPs with regard to the design of amphipathicity, it is complicated to study the structure-activity relationships. Therefore, this work aims to categorize the common amphipathic design and investigate their impact on the biological properties of AMPs. Besides, the connection between current structural modification approaches and amphipathic styles was also discussed.
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Affiliation(s)
| | - Hoa Doan Ngan
- Faculty of Medical Technology, PHENIKAA University, Hanoi, 12116, Vietnam
| | - Binh Le Huy
- Center for High Technology Development, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Hanoi, 11307, Vietnam
- School of Chemical Engineering -, Hanọi University of Science and Technology, 1 Dai Co Viet, Hai Ba Trung, Hanoi, 11615, Vietnam
| | - Hoang Vu Dinh
- School of Chemical Engineering -, Hanọi University of Science and Technology, 1 Dai Co Viet, Hai Ba Trung, Hanoi, 11615, Vietnam
| | - Huy Luong Xuan
- Faculty of Pharmacy, PHENIKAA University, Hanoi, 12116, Vietnam
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6
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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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7
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Hirano M, Yokoo H, Ohoka N, Ito T, Misawa T, Oba M, Inoue T, Demizu Y. Rational Design of Amphipathic Antimicrobial Peptides with Alternating L-/D-Amino Acids That Form Helical Structures. Chem Pharm Bull (Tokyo) 2024; 72:149-154. [PMID: 38296556 DOI: 10.1248/cpb.c23-00465] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Antimicrobial peptides (AMPs) are promising therapeutic agents against bacteria. We have previously reported an amphipathic AMP Stripe composed of cationic L-Lys and hydrophobic L-Leu/L-Ala residues, and Stripe exhibited potent antimicrobial activity against Gram-positive and Gram-negative bacteria. Gramicidin A (GA), composed of repeating sequences of L- and D-amino acids, has a unique β6.3-helix structure and exhibits broad antimicrobial activity. Inspired by the structural properties and antimicrobial activities of LD-alternating peptides such as GA, in this study, we designed Stripe derivatives with LD-alternating sequences. We found that simply alternating L- and D-amino acids in the Stripe sequence to give StripeLD caused a reduction in antimicrobial activity. In contrast, AltStripeLD, with cationic and hydrophobic amino acids rearranged to yield an amphipathic distribution when the peptide adopts a β6.3-helix, displayed higher antimicrobial activity than AltStripe. These results suggest that alternating L-/D-cationic and L-/D-hydrophobic amino acids in accordance with the helical structure of an AMP may be a useful way to improve antimicrobial activity and develop new AMP drugs.
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Affiliation(s)
- Motoharu Hirano
- National Institute of Health Sciences
- Graduate School of Medical Life Science, Yokohama City University
| | - Hidetomo Yokoo
- National Institute of Health Sciences
- Medical Chemistry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine
| | | | - Takahito Ito
- National Institute of Health Sciences
- Graduate School of Medical Life Science, Yokohama City University
| | | | - Makoto Oba
- Medical Chemistry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine
| | | | - Yosuke Demizu
- National Institute of Health Sciences
- Graduate School of Medical Life Science, Yokohama City University
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8
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Ito T, Yokoo H, Kato T, Doi M, Demizu Y. Sculpting Secondary Structure of a Cyclic Peptide: Conformational Analysis of a Cyclic Hexapeptide Containing a Combination of l-Leu, d-Leu, and Aib Residues. ACS OMEGA 2023; 8:44106-44111. [PMID: 38027316 PMCID: PMC10666233 DOI: 10.1021/acsomega.3c06397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 10/23/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023]
Abstract
We have previously reported that cyclo(l-Leu-d-Leu-Aib-l-Leu-d-Leu-Aib) (2), a cyclic hexapeptide consisting of heterochiral l-Leu and d-Leu (l-Leu-d-Leu) residues with achiral 2-aminoisobutyric acid (Aib) residues, forms a figure-8 conformation. In this study, we newly designed cyclo(l-Leu-d-Leu-Aib-d-Leu-l-Leu-Aib)+ (4), an epimer of 2, and examined the conformational differences between 2 and 4 by X-ray crystallographic analysis. Peptide 4 formed a planar cyclic conformation with an antiparallel β-sheet hydrogen-bonding pattern. This investigation demonstrates the potential to manipulate the molecular conformation of cyclic peptides by simply arranging the l- and d-amino acids and emphasizes that diverse conformations can be obtained by using cyclic peptides. Harnessing cyclic peptides as platforms for distinct molecular structures is a promising approach to expanding the chemical space for various applications.
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Affiliation(s)
- Takahito Ito
- Division
of Organic Chemistry, National Institute
of Health Sciences, Kawasaki, Kanagawa 210-9501, Japan
- Graduate
School of Medical Life Science, Yokohama
City University, Yokohama, Kanagawa 236-0027, Japan
| | - Hidetomo Yokoo
- Division
of Organic Chemistry, National Institute
of Health Sciences, Kawasaki, Kanagawa 210-9501, Japan
| | - Takuma Kato
- Faculty
of Pharmacy, Osaka Medical and Pharmaceutical
University, Takatsuki, Osaka 569-8686, Japan
| | - Mitsunobu Doi
- Faculty
of Pharmacy, Osaka Medical and Pharmaceutical
University, Takatsuki, Osaka 569-8686, Japan
| | - Yosuke Demizu
- Division
of Organic Chemistry, National Institute
of Health Sciences, Kawasaki, Kanagawa 210-9501, Japan
- Graduate
School of Medical Life Science, Yokohama
City University, Yokohama, Kanagawa 236-0027, Japan
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9
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Shah SKH, Modi U, Patel K, James A, N S, De S, Vasita R, Prabhakaran P. Site-selective post-modification of short α/γ hybrid foldamers: a powerful approach for molecular diversification towards biomedical applications. Biomater Sci 2023; 11:6210-6222. [PMID: 37526301 DOI: 10.1039/d3bm00766a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
The extensive research work in the exhilarating area of foldamers (artificial oligomers possessing well-defined conformation in solution) has shown them to be promising candidates in biomedical research and materials science. The post-modification approach is successful in peptides, proteins, and polymers to modulate their functions. To the best of our knowledge, site-selective post-modification of a foldamer affording molecules with different pendant functional groups within a molecular scaffold has not yet been reported. We demonstrate for the first time that late-stage site-selective functionalization of short hybrid oligomers is an efficient approach to afford molecules with diverse functional groups. In this article, we report the design and synthesis of hybrid peptides with repeating units of leucine (Leu) and 5-amino salicylic acid (ASA), regioselective post-modification, conformational analyses (based on solution-state NMR, circular dichroism and computational studies) and morphological studies of the peptide nanostructures. As a proof-of-concept, we demonstrate the applications of differently modified peptides as drug delivery agents, imaging probes, and anticancer agents. The novel feature of the work is that the difference in reactivity of two phenolic OH groups in short biomimetic peptides was utilized to achieve site-selective post-modification. It is challenging to apply the same approach to short α-peptides having a poor folding tendency, and their post-functionalization may considerably affect their conformation.
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Affiliation(s)
| | - Unnati Modi
- School of Life Sciences, Central University of Gujarat, Gandhinagar 382030, India
| | - Karma Patel
- School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India.
| | - Anjima James
- Department of Applied Chemistry, Cochin University of Science and Technology, Kochi 682022, India
| | - Sreerag N
- School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India.
| | - Susmita De
- Department of Chemistry, University of Calicut, Calicut 673635, India
| | - Rajesh Vasita
- School of Life Sciences, Central University of Gujarat, Gandhinagar 382030, India
| | - Panchami Prabhakaran
- School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, India.
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10
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Sang P, Cai J. Unnatural helical peptidic foldamers as protein segment mimics. Chem Soc Rev 2023; 52:4843-4877. [PMID: 37401344 PMCID: PMC10389297 DOI: 10.1039/d2cs00395c] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Indexed: 07/05/2023]
Abstract
Unnatural helical peptidic foldamers have attracted considerable attention owing to their unique folding behaviours, diverse artificial protein binding mechanisms, and promising applications in chemical, biological, medical, and material fields. Unlike the conventional α-helix consisting of molecular entities of native α-amino acids, unnatural helical peptidic foldamers are generally comprised of well-defined backbone conformers with unique and unnatural structural parameters. Their folded structures usually arise from unnatural amino acids such as N-substituted glycine, N-substituted-β-alanine, β-amino acid, urea, thiourea, α-aminoxy acid, α-aminoisobutyric acid, aza-amino acid, aromatic amide, γ-amino acid, as well as sulfono-γ-AA amino acid. They can exhibit intriguing and predictable three-dimensional helical structures, generally featuring superior resistance to proteolytic degradation, enhanced bioavailability, and improved chemodiversity, and are promising in mimicking helical segments of various proteins. Although it is impossible to include every piece of research work, we attempt to highlight the research progress in the past 10 years in exploring unnatural peptidic foldamers as protein helical segment mimics, by giving some representative examples and discussing the current challenges and future perspectives. We expect that this review will help elucidate the principles of structural design and applications of existing unnatural helical peptidic foldamers in protein segment mimicry, thereby attracting more researchers to explore and generate novel unnatural peptidic foldamers with unique structural and functional properties, leading to more unprecedented and practical applications.
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Affiliation(s)
- Peng Sang
- Tianjian Laboratory of Advanced Biomedical Sciences, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, China.
| | - Jianfeng Cai
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA.
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11
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Chowdhary R, Mubarak MM, Kantroo HA, Ur Rahim J, Malik A, Sarkar AR, Bashir G, Ahmad Z, Rai R. Synthesis, Characterization, and Antimicrobial Activity of Ultra-Short Cationic β-Peptides. ACS Infect Dis 2023; 9:1437-1448. [PMID: 37399583 DOI: 10.1021/acsinfecdis.3c00238] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2023]
Abstract
The development of new antibiotics is urgently required because of the rapidly growing resistance against conventional antibiotics. The antimicrobial peptides show potential as small antibiotic molecules. The stability of peptides is a primary concern for the use of peptides as drugs. Introducing β-amino acids into peptide sequences can be useful in preventing biological degradation by proteolytic enzymes. Herein, we describe the synthesis, characterization, and antimicrobial activity of ultra-short cationic β-peptides, LA-β3,3-Pip-β2,2-Ac6c-PEA, P1; LA-β3,3-Pip(G)-β2,2-Ac6c-PEA, P2; LAU-β3,3-Pip-β2,2-Ac6c-PEA, P3, and LAU-β3,3-Pip(G)-β2,2-Ac6c-PEA, P4. Peptides P1-P4 were evaluated against Gram-negative, Gram-positive, MRSA, and multi-drug resistant E. coli (MDR-E. coli). P3 exhibited the most potent antimicrobial activity against E. coli, S. epidermidis, S. aureus, K. pneumoniae, S. mutans, and E. faecalis, with MIC values 0.5, 2, 0.5, 1, 2, and 1 μg/mL, respectively. P3 exhibited time- and concentration-dependent bactericidal activities against E. coli, S. aureus, and E. faecalis with a killing rate of 1.6 logs/h. The treatment of E. coli with peptide P3 showed membrane disruption. In addition, P3 exhibited the inhibition of biofilm produced by E. coli, synergism with antibiotics (ciprofloxacin, streptomycin, and ampicillin), 100% cell viability against AML12, RAW 264.7, and HEK-293 cell lines at 1, and 10 μg/mL concentrations.
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Affiliation(s)
- Rubina Chowdhary
- Natural Products &Medicinal Chemistry Division, CSIR - Institute of Integrative Medicine, Canal Road, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Mohamad Mosa Mubarak
- Clinical Microbiology PK/PD Division, CSIR - Indian Institute of Integrative Medicine, Sanatnagar, Srinagar 190005, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Hadiya A Kantroo
- Clinical Microbiology PK/PD Division, CSIR - Indian Institute of Integrative Medicine, Sanatnagar, Srinagar 190005, India
| | - Junaid Ur Rahim
- Natural Products &Medicinal Chemistry Division, CSIR - Institute of Integrative Medicine, Canal Road, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Abbass Malik
- Clinical Microbiology PK/PD Division, CSIR - Indian Institute of Integrative Medicine, Sanatnagar, Srinagar 190005, India
| | - Aminur Rahman Sarkar
- Natural Products &Medicinal Chemistry Division, CSIR - Institute of Integrative Medicine, Canal Road, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Gulnaz Bashir
- Department of Microbiology, Sher-I-Kashmir Institute of Medical Sciences, Srinagar 190011, India
| | - Zahoor Ahmad
- Clinical Microbiology PK/PD Division, CSIR - Indian Institute of Integrative Medicine, Sanatnagar, Srinagar 190005, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Rajkishor Rai
- Natural Products &Medicinal Chemistry Division, CSIR - Institute of Integrative Medicine, Canal Road, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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12
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Nagata M, Watanabe M, Doi R, Uemura M, Ochiai N, Ichinose W, Fujiwara K, Sato Y, Kameda T, Takeuchi K, Shuto S. Helix-forming aliphatic homo-δ-peptide foldamers based on the conformational restriction effects of cyclopropane. Org Biomol Chem 2023; 21:970-980. [PMID: 36426637 DOI: 10.1039/d2ob01715f] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Considerable effort has been directed toward developing artificial peptide-based foldamers. However, detailed structural analysis of δ-peptide foldamers consisting of only aliphatic δ-amino acids has not been reported. Herein, we rationally designed and stereoselectively synthesized aliphatic homo-δ-peptides forming a stable helical structure by using a chiral cyclopropane δ-amino acid as a monomer unit. Structural analysis of the homo-δ-peptides using circular dichroism, infrared, and NMR spectroscopy indicated that they form a stable 14-helical structure in solution. Furthermore, we successfully conducted X-ray crystallographic analysis of the homo-δ-peptides, demonstrating a right-handed 14-helical structure. This helical structure of the crystal was consistent with those predicted by theoretical calculations and those obtained based on NMR spectroscopy in solution. This stable helical structure is due to the effective restriction of the backbone conformation by the structural characteristics of cyclopropane. This work reports the first example of aliphatic homo-δ-peptide foldamers having a stable helical structure both in the solution and crystal states.
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Affiliation(s)
- Makoto Nagata
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Mizuki Watanabe
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Ryohei Doi
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Mai Uemura
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Nanase Ochiai
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Wataru Ichinose
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Koichi Fujiwara
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Yoshihiro Sato
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
| | - Tomoshi Kameda
- Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Koh Takeuchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Satoshi Shuto
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
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13
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Structure-Activity Relationship Studies of Substitutions of Cationic Amino Acid Residues on Antimicrobial Peptides. Antibiotics (Basel) 2022; 12:antibiotics12010019. [PMID: 36671220 PMCID: PMC9854868 DOI: 10.3390/antibiotics12010019] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 12/25/2022] Open
Abstract
Antimicrobial peptides (AMPs) have received considerable attention as next-generation drugs for infectious diseases. Amphipathicity and the formation of a stabilized secondary structure are required to exert their antimicrobial activity by insertion into the microbial membrane, resulting in lysis of the bacteria. We previously reported the development of a novel antimicrobial peptide, 17KKV, based on the Magainin 2 sequence. The peptide was obtained by increasing the amphipathicity due to the replacement of amino acid residues. Moreover, we studied the structural development of 17KKV and revealed that the secondary structural control of 17KKV by the introduction of non-proteinogenic amino acids such as α,α-disubstituted amino acids or side-chain stapling enhanced its antimicrobial activity. Among them, peptide 1, which contains 2-aminobutyric acid residues in the 17KKV sequence, showed potent antimicrobial activity against multidrug-resistant Pseudomonus aeruginosa (MDRP) without significant hemolytic activity against human red blood cells. However, the effects of cationic amino acid substitutions on secondary structures and antimicrobial activity remain unclear. In this study, we designed and synthesized a series of peptide 1 by the replacement of Lys residues with several types of cationic amino acids and evaluated their secondary structures, antimicrobial activity, hemolytic activity, and resistance against digestive enzymes.
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14
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Cai X, Orsi M, Capecchi A, Köhler T, van Delden C, Javor S, Reymond JL. An intrinsically disordered antimicrobial peptide dendrimer from stereorandomized virtual screening. CELL REPORTS. PHYSICAL SCIENCE 2022; 3:101161. [PMID: 36632208 PMCID: PMC9780108 DOI: 10.1016/j.xcrp.2022.101161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/21/2022] [Accepted: 11/02/2022] [Indexed: 06/17/2023]
Abstract
Membrane-disruptive amphiphilic antimicrobial peptides behave as intrinsically disordered proteins by being unordered in water and becoming α-helical in contact with biological membranes. We recently discovered that synthesizing the α-helical antimicrobial peptide dendrimer L-T25 ((KL)8(KKL)4(KLL)2 KKLL) using racemic amino acids to form stereorandomized sr-T25, an analytically pure mixture of all possible diastereoisomers of L-T25, preserved antibacterial activity but abolished hemolysis and cytotoxicity, pointing to an intrinsically disordered antibacterial conformation and an α-helical cytotoxic conformation. In this study, to identify non-toxic intrinsically disordered homochiral antimicrobial peptide dendrimers (AMPDs), we surveyed sixty-three sr-analogs of sr-T25 selected by virtual screening. One of the analogs, sr-X18 ((KL)8(KLK)4(KLL)2 KLLL), lost antibacterial activity as L-enantiomer and became hemolytic due to α-helical folding. By contrast, the L- and D-enantiomers of sr-X22 ((KL)8(KL)4(KKLL)2 KLKK) were equally antibacterial, non-hemolytic, and non-toxic, implying an intrinsically disordered bioactive conformation. Screening stereorandomized libraries may be generally useful to identify or optimize intrinsically disordered bioactive peptides.
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Affiliation(s)
- Xingguang Cai
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Markus Orsi
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Alice Capecchi
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Thilo Köhler
- Department of Microbiology and Molecular Medicine, University of Geneva, Service of Infectious Diseases, University Hospital of Geneva, Geneva, Switzerland
| | - Christian van Delden
- Department of Microbiology and Molecular Medicine, University of Geneva, Service of Infectious Diseases, University Hospital of Geneva, Geneva, Switzerland
| | - Sacha Javor
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
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15
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Development of a Penetratin-Conjugated Stapled Peptide that Inhibits Wnt/β-Catenin Signaling. Bioorg Med Chem 2022; 73:117021. [DOI: 10.1016/j.bmc.2022.117021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/09/2022] [Accepted: 09/13/2022] [Indexed: 11/18/2022]
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16
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Boruah A, Roy A. Advances in hybrid peptide-based self-assembly systems and their applications. Biomater Sci 2022; 10:4694-4723. [PMID: 35899853 DOI: 10.1039/d2bm00775d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Self-assembly of peptides demonstrates a great potential for designing highly ordered, finely tailored supramolecular arrangements enriched with high specificity, improved efficacy and biological activity. Along with natural peptides, hybrid peptide systems composed of natural and chemically diverse unnatural amino acids have been used in various fields, including drug delivery, wound healing, potent inhibition of diseases, and prevention of biomaterial related diseases to name a few. In this review, we provide a brief outline of various methods that have been utilized for obtaining fascinating structures that create an avenue to reproduce a range of functions resulting from these folds. An overview of different self-assembled structures as well as their applications will also be provided. We believe that this review is very relevant to the current scenario and will cover conformations of hybrid peptides and resulting self-assemblies from the late 20th century through 2022. This review aims to be a comprehensive and reliable account of the hybrid peptide-based self-assembly owing to its enormous influence in understanding and mimicking biological processes.
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Affiliation(s)
- Alpana Boruah
- Applied Organic Chemistry Group, Chemical Sciences and Technology Division, Council of Scientific and Industrial Research-North East Institute of Science and Technology (CSIR-NEIST), Pulibor, Jorhat-785006, Assam, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Arup Roy
- Applied Organic Chemistry Group, Chemical Sciences and Technology Division, Council of Scientific and Industrial Research-North East Institute of Science and Technology (CSIR-NEIST), Pulibor, Jorhat-785006, Assam, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
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17
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Takayama K. Peptide Tool-Driven Functional Elucidation of Biomolecules Related to Endocrine System and Metabolism. Chem Pharm Bull (Tokyo) 2022; 70:413-419. [PMID: 35650039 DOI: 10.1248/cpb.c22-00048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The enhancement of basic research based on biomolecule-derived peptides has the potential to elucidate their biological function and lead to the development of new drugs. In this review, two biomolecules, namely "neuromedin U (NMU)" and "myostatin," are discussed. NMU, a neuropeptide first isolated from the porcine spinal cord, non-selectively activates two types of receptors (NMUR1 and NMUR2) and displays a variety of physiological actions, including appetite suppression. The development of receptor-selective regulators helps elucidate each receptor's detailed biological roles. A structure-activity relationship (SAR) study was conducted to achieve this purpose using the amidated C-terminal core structure of NMU for receptor activation. Through obtaining receptor-selective hexapeptide agonists, molecular functions of the core structure were clarified. Myostatin is a negative regulator of skeletal muscle growth and has attracted attention as a target for treating atrophic muscle disorders. Although the protein inhibitors, such as antibodies and receptor-decoys have been developed, the inhibition by smaller molecules, including peptides, is less advanced. Focusing on the inactivation mechanism by prodomain proteins derived from myostatin-precursor, a first mid-sized α-helical myostatin-inhibitory peptide (23-mer) was identified from the mouse sequence. The detailed SAR study based on this peptide afforded the structural requirements for effective inhibition. The subsequent computer simulation proposed the docking mode at the activin type I receptor binding site of myostatin. The resulting development of potent inhibitors suggested the existence of a more appropriate binding mode linked to their β-sheet forming properties, suggesting that further investigations might be needed.
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Affiliation(s)
- Kentaro Takayama
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University
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18
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Helical Foldamers and Stapled Peptides as New Modalities in Drug Discovery: Modulators of Protein-Protein Interactions. Processes (Basel) 2022. [DOI: 10.3390/pr10050924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A “foldamer” is an artificial oligomeric molecule with a regular secondary or tertiary structure consisting of various building blocks. A “stapled peptide” is a peptide with stabilized secondary structures, in particular, helical structures by intramolecular covalent side-chain cross-linking. Helical foldamers and stapled peptides are potential drug candidates that can target protein-protein interactions because they enable multipoint molecular recognition, which is difficult to achieve with low-molecular-weight compounds. This mini-review describes a variety of peptide-based foldamers and stapled peptides with a view to their applications in drug discovery, including our recent progress.
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19
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Abstract
We report the development of peptidomimetic antibiotics derived from a natural antimicrobial peptide, human α-defensin 5. By engaging multiple bacterial targets, the lead compound is efficacious in vitro and in vivo against bacteria with highly inducible antibiotic resistance, promising a useful therapeutic agent for the treatment of infections caused by antibiotic-resistant bacteria. Antibiotics with multiple mechanisms of action and broad-spectrum are urgently required to combat the growing health threat posed by resistant pathogenic microorganisms. Combining computational and medicinal chemistry tools, we used the structure of human α-defensin 5 (HD5) to design a class of peptidomimetic antibiotics with improved activity against both gram-negative and gram-positive bacteria. The most promising lead, compound 10, showed potent killing of multiple drug-resistant gram-negative bacteria isolated from patients. Compound 10 exhibited a multiplex mechanism of action through targeting membrane components—outer membrane protein A and lipopolysaccharide, as well as a potential intracellular target—70S ribosome, thus causing membrane perturbation and inhibition of protein synthesis. In vivo efficacy, stability, and safety of compound 10 were also validated. This human defensin-inspired synthetic peptidomimetic could help solve the serious problem of drug resistance to conventional antibiotics.
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20
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Cai X, Javor S, Gan BH, Köhler T, Reymond JL. The antibacterial activity of peptide dendrimers and polymyxin B increases sharply above pH 7.4. Chem Commun (Camb) 2021; 57:5654-5657. [PMID: 33972964 PMCID: PMC8186529 DOI: 10.1039/d1cc01838h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/04/2021] [Indexed: 12/25/2022]
Abstract
pH-activity profiling reveals that antimicrobial peptide dendrimers (AMPDs) kill Klebsiella pneumoniae and Methicillin-resistant Staphylococcus aureus (MRSA) at pH = 8.0, against which they are inactive at pH = 7.4, due to stronger electrostatic binding to bacterial cells at higher pH. A similar effect occurs with polymyxin B and might be general for polycationic antimicrobials.
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Affiliation(s)
- Xingguang Cai
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland.
| | - Sacha Javor
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland.
| | - Bee Ha Gan
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland.
| | - Thilo Köhler
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland.
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