1
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Shi L, Zhao W, Jiu Z, Guo J, Zhu Q, Sun Y, Zhu B, Chang J, Xin P. Redox-Regulated Synthetic Channels: Enabling Reversible Ion Transport by Modulating the Ion-Permeation Pathway. Angew Chem Int Ed Engl 2024; 63:e202403667. [PMID: 38407803 DOI: 10.1002/anie.202403667] [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: 02/21/2024] [Revised: 02/25/2024] [Accepted: 02/26/2024] [Indexed: 02/27/2024]
Abstract
Natural redox-regulated channel proteins often utilize disulfide bonds as redox sensors for adaptive regulation of channel conformations in response to diverse physiological environments. In this study, we developed novel synthetic ion channels capable of reversibly switching their ion-transport capabilities by incorporating multiple disulfide bonds into artificial systems. X-ray structural analysis and electrophysiological experiments demonstrated that these disulfide-bridged molecules possess well-defined tubular cavities and can be efficiently inserted into lipid bilayers to form artificial ion channels. More importantly, the disulfide bonds in these molecules serve as redox-tunable switches to regulate the formation and disruption of ion-permeation pathways, thereby achieving a transition in the transmembrane transport process between the ON and OFF states.
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Affiliation(s)
- Linlin Shi
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Wen Zhao
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Zhihui Jiu
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Jingjing Guo
- Centre in Artificial Intelligence Driven Drug Discovery, Faculty of Applied Sciences, Macao Polytechnic University, Macao, 999078, China
| | - Qiuhui Zhu
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Yonghui Sun
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Bo Zhu
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Junbiao Chang
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
| | - Pengyang Xin
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, NMPA Key Laboratory for Research and Evaluation of Innovative Drug, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
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2
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Johnson TG, Docker A, Sadeghi-Kelishadi A, Langton MJ. Halogen bonding relay and mobile anion transporters with kinetically controlled chloride selectivity. Chem Sci 2023; 14:5006-5013. [PMID: 37206385 PMCID: PMC10189858 DOI: 10.1039/d3sc01170d] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 04/03/2023] [Indexed: 05/21/2023] Open
Abstract
Selective transmembrane transport of chloride over competing proton or hydroxide transport is key for the therapeutic application of anionophores, but remains a significant challenge. Current approaches rely on enhancing chloride anion encapsulation within synthetic anionophores. Here we report the first example of a halogen bonding ion relay in which transport is facilitated by the exchange of ions between lipid-anchored receptors on opposite sides of the membrane. The system exhibits non-protonophoric chloride selectivity, uniquely arising from the lower kinetic barrier to chloride exchange between transporters within the membrane, compared to hydroxide, with selectivity maintained across membranes with different hydrophobic thicknesses. In contrast, we demonstrate that for a range of mobile carriers with known high chloride over hydroxide/proton selectivity, the discrimination is strongly dependent on membrane thickness. These results demonstrate that the selectivity of non-protonophoric mobile carriers does not arise from ion binding discrimination at the interface, but rather through a kinetic bias in transport rates, arising from differing membrane translocation rates of the anion-transporter complexes.
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Affiliation(s)
- Toby G Johnson
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Andrew Docker
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Amir Sadeghi-Kelishadi
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Matthew J Langton
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
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3
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Koshiyama T, Inoue Y, Asada S, Kawahara K, Ide S, Yasuhara K, Ohba M. pH-Dependent ion permeability control of a modified amphotericin B channel through metal complexation. Chem Commun (Camb) 2021; 57:2895-2898. [PMID: 33606865 DOI: 10.1039/d0cc08368b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Amphotericin B incorporating 2,2'-bipyridine (bpy-AmB) forms a membrane channel exhibiting pH-dependent Ca2+ ion permeability with a selective response to Cu2+ ions. The coordination structure at bpy sites depends on the pH and metal ions can control the association state of bpy-AmB in the membrane.
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Affiliation(s)
- Tomomi Koshiyama
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577, Japan.
| | - Yuki Inoue
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Sana Asada
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Koki Kawahara
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Shogo Ide
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Kazuma Yasuhara
- Division of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Masaaki Ohba
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
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4
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Xiao Q, Haoyang WW, Lin T, Li ZT, Zhang DW, Hou JL. Unimolecular artificial transmembrane channels showing reversible ligand-gating behavior. Chem Commun (Camb) 2021; 57:863-866. [PMID: 33439165 DOI: 10.1039/d0cc06974d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A series of peptide-appended bisresorcinarenes were synthesized, which adopted tubular conformation induced by intramolecular hydrogen bonds. The derivatives formed unimolecular artificial transmembrane channels in lipid bilayers to enable selective transport of monovalent cations. Importantly, the channels exhibited reversible ligand-gating behavior in response to alkyl amine and Cu2+.
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Affiliation(s)
- Qi Xiao
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China.
| | - Wei-Wei Haoyang
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China.
| | - Tao Lin
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China.
| | - Zhan-Ting Li
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China.
| | - Dan-Wei Zhang
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China.
| | - Jun-Li Hou
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China.
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5
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Sasaki R, Sato K, Tabata KV, Noji H, Kinbara K. Synthetic Ion Channel Formed by Multiblock Amphiphile with Anisotropic Dual-Stimuli-Responsiveness. J Am Chem Soc 2021; 143:1348-1355. [DOI: 10.1021/jacs.0c09470] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Ryo Sasaki
- School of Life Science and Technology, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Kohei Sato
- School of Life Science and Technology, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Kazuhito V. Tabata
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroyuki Noji
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kazushi Kinbara
- School of Life Science and Technology, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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6
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Hu X, Yang H. A reversible single-molecule ligand-gating ion transportation switch of ON–OFF–ON type through a photoresponsive pillar[6]arene channel complex. RSC Adv 2021; 11:7450-7453. [PMID: 35423228 PMCID: PMC8695115 DOI: 10.1039/d0ra10871e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 02/08/2021] [Indexed: 12/04/2022] Open
Abstract
A reversible pseudo-single-ligand-gated ion transportation switch of ON–OFF–ON type was achieved through host–guest complexation with pillar[6]arene (P[6]) as the ion channel, and a photoresponsive azobenzene as the dual-role (open and close) ligand. A reversible pseudo-single-ligand-gated ion transportation switch of ON–OFF–ON type through pillar[6]arene and photoresponsive azobenzene as dual-role ligand.![]()
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Affiliation(s)
- Xinyu Hu
- Key Laboratory of Micro-Nano Optoelectronic Devices (Wenzhou)
- College of Electrical and Electronic Engineering
- Wenzhou University
- Wenzhou 325035
- People's Republic of China
| | - Haishen Yang
- Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power
- Shanghai University of Electric Power
- Shanghai
- People's Republic of China
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7
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8
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Bai D, Yan T, Wang S, Wang Y, Fu J, Fang X, Zhu J, Liu J. Reversible Ligand‐Gated Ion Channel via Interconversion between Hollow Single Helix and Intertwined Double Helix. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201916755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Dongya Bai
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Tengfei Yan
- College of Materials Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou 311121 China
| | - Shi Wang
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Yanbo Wang
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Jiya Fu
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Xiaomin Fang
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Junyan Zhu
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Junqiu Liu
- College of Materials Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou 311121 China
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9
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Bai D, Yan T, Wang S, Wang Y, Fu J, Fang X, Zhu J, Liu J. Reversible Ligand‐Gated Ion Channel via Interconversion between Hollow Single Helix and Intertwined Double Helix. Angew Chem Int Ed Engl 2020; 59:13602-13607. [DOI: 10.1002/anie.201916755] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 04/13/2020] [Indexed: 12/16/2022]
Affiliation(s)
- Dongya Bai
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Tengfei Yan
- College of Materials Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou 311121 China
| | - Shi Wang
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Yanbo Wang
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Jiya Fu
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Xiaomin Fang
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Junyan Zhu
- Institute of Functional Organic Molecular Engineering Henan Engineering Laboratory of Flame-Retardant and Functional Materials College of Chemistry and Chemical Engineering Henan University Kaifeng 475004 China
| | - Junqiu Liu
- College of Materials Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou 311121 China
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10
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Vanuytsel S, Carniello J, Wallace MI. Artificial Signal Transduction across Membranes. Chembiochem 2019; 20:2569-2580. [DOI: 10.1002/cbic.201900254] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/09/2019] [Indexed: 12/18/2022]
Affiliation(s)
- Steven Vanuytsel
- Department of ChemistryKing's College London Britannia House 7 Trinity Street London SE1 1DB UK
- London Centre for Nanotechnology Strand London WC2R 2LS UK
| | - Joanne Carniello
- Department of ChemistryKing's College London Britannia House 7 Trinity Street London SE1 1DB UK
- London Centre for Nanotechnology Strand London WC2R 2LS UK
| | - Mark Ian Wallace
- Department of ChemistryKing's College London Britannia House 7 Trinity Street London SE1 1DB UK
- London Centre for Nanotechnology Strand London WC2R 2LS UK
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11
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Hu X, Liu N, Yang H, Wu F, Chen X, Li C, Chen X. A reversible ion transportation switch of ON–OFF–ON type by a ligand-gated calix[6]arene channel. Chem Commun (Camb) 2019; 55:3008-3011. [DOI: 10.1039/c9cc00732f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calix[6]arene (CX6) was found to be an efficient ion transmembrane channel, which could be blocked by methylene blue (MB) through host–guest interactions.
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Affiliation(s)
- Xinyu Hu
- College of Mathematic and Electronic Information Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
| | - Nannan Liu
- College of Chemistry and Materials Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
| | - Haishen Yang
- Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power
- Shanghai University of Electric Power
- Shanghai
- China
| | - Fen Wu
- College of Chemistry and Materials Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
| | - Xi Chen
- College of Mathematic and Electronic Information Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
| | - Canpeng Li
- School of Chemical Science and Technology
- Yunnan University
- Kunming 650091
- P. R. China
| | - Xiaojing Chen
- College of Mathematic and Electronic Information Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
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12
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Abstract
The controllable synthetic ion channels with voltage-, ligand- light- and mechano-gating, as well as rectifying behaviours are discussed in regarding to their construction strategies and functions.
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Affiliation(s)
- Jian-Yu Chen
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Jun-Li Hou
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
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13
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Wu X, Gale PA. Small-Molecule Uncoupling Protein Mimics: Synthetic Anion Receptors as Fatty Acid-Activated Proton Transporters. J Am Chem Soc 2016; 138:16508-16514. [PMID: 27998096 DOI: 10.1021/jacs.6b10615] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Uncoupling proteins (UCPs) regulate energy expenditure in living cells by inducing proton leakage across the mitochondrial inner membrane, thereby uncoupling adenosine diphosphate phosphorylation from nutrient oxidation. The proton transport activity of UCP1 and UCP2 requires activation by fatty acids. We report here the first examples of synthetic neutral anion receptors performing this biologically important fatty acid-activated function in phospholipid bilayers. We have shown that a tripodal thiourea possesses poor H+/OH- transport activity without fatty acids, but in the presence of long-chain fatty acids is "switched on" as a proton transporter with an activity close to that of a commonly used protonophore. The fatty acid-enhanced proton transport was also observed for other hydrogen and halogen bond-based synthetic anion transporters. We propose that these compounds induce proton permeability by catalyzing transbilayer movement ("flip-flop") of anionic forms of fatty acids, so allowing the fatty acids to complete a proton transport cycle. Several lines of evidence have been provided to support such a fatty acid cycling mechanism. Our findings open up new applications of anion receptor chemistry and provide important clues for understanding biological activities of synthetic anion transporters and potentially the uncoupling mechanism of naturally occurring membrane proteins.
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Affiliation(s)
- Xin Wu
- Chemistry, University of Southampton , Southampton SO17 1BJ, U.K
| | - Philip A Gale
- Chemistry, University of Southampton , Southampton SO17 1BJ, U.K
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14
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Affiliation(s)
- Sundus Erbas-Cakmak
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - David A. Leigh
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Charlie T. McTernan
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Alina
L. Nussbaumer
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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15
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Muraoka T, Endo T, Tabata KV, Noji H, Nagatoishi S, Tsumoto K, Li R, Kinbara K. Reversible Ion Transportation Switch by a Ligand-Gated Synthetic Supramolecular Ion Channel. J Am Chem Soc 2014; 136:15584-95. [DOI: 10.1021/ja5070312] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Takahiro Muraoka
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1,
Katahira, Aoba-ku, Sendai 980-8577, Japan
- PRESTO, Japan Science and Technology Agency, 4-1-8, Honcho, Kawaguchi,
Saitama 332-0012, Japan
| | - Takahiro Endo
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1,
Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Kazuhito V. Tabata
- Department
of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku,
Tokyo 113-8656, Japan
| | - Hiroyuki Noji
- Department
of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku,
Tokyo 113-8656, Japan
| | - Satoru Nagatoishi
- Department
of Bioengineering, The University of Tokyo, Bunkyo-ku, Tokyo 108-8656, Japan
| | - Kouhei Tsumoto
- Department
of Bioengineering, The University of Tokyo, Bunkyo-ku, Tokyo 108-8656, Japan
- Department
of Chemistry and Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo 108-8656, Japan
- Institute
of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Rui Li
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1,
Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Kazushi Kinbara
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1,
Katahira, Aoba-ku, Sendai 980-8577, Japan
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16
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Futaki S, Noshiro D, Kiwada T, Asami K. Extramembrane control of ion channel peptide assemblies, using alamethicin as an example. Acc Chem Res 2013; 46:2924-33. [PMID: 23680081 DOI: 10.1021/ar400051f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ion channels allow the influx and efflux of specific ions through a plasma membrane. Many ion channels can sense, for example, the membrane potential (the voltage gaps between the inside and the outside of the membrane), specific ligands such as neurotransmitters, and mechanical tension within the membrane. They modulate cell function in response to these stimuli. Researchers have focused on developing peptide- and non-peptide-based model systems to elucidate ion-channel protein functions and to create artificial sensing systems. In this Account, we employed a typical peptide that forms ion channels,alamethicin, as a model to evaluate our methodologies for controlling the assembly states of channel-forming molecules in membranes. As alamethicin self-assembles in membranes, it prompts channel formation, but number of peptide molecules in these channels is not constant. Using planar-lipid bilayer methods, we monitored the association states of alamethicin in real time. Many ligand-gated, natural-ion channel proteins have large extramembrane domains. As these proteins interact with specific ligands, those conformational alterations in the extramembrane domains are transmitted to the transmembrane, pore-forming domains to open and close the channels. We hypothesized that if we conjugated suitable extramembrane segments to alamethicin, ligand binding to the extramembrane segments could alter the structure of the extramembrane domains and influence the association states or association numbers of alamethicin in the membranes. We could then assess those changes by using single-channel current recording. We found that we could modulate channel assembly and eventual ion flux with attached leucine-zipper extramembrane peptide segments. Using conformationally switchable leucine-zipper extramembrane segments that respond to Fe(3+), we fabricated an artificial Fe(3+)-sensitive ion channel; a decrease in the helical content of the extramembrane segment led to an increase in the channel current. When we added a calmodulin C-terminus segment, we formed a channel that was sensitive to Ca(2+). This result demonstrated that we could prepare artificial channels that were sensitive to specific ligands by adding appropriate extramembrane segments from natural protein motifs that respond to external stimuli. In conclusion, our research points to the possibility of creating tailored sensor or signal transduction systems through the conjugation of a conformationally switchable extramembrane peptide/protein segment to a suitable transmembrane peptide segment.
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Affiliation(s)
- Shiroh Futaki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Daisuke Noshiro
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Tatsuto Kiwada
- Faculty of Pharmaceutical Sciences, Institute of Medical, Pharmaceutical, and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Koji Asami
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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17
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Busseron E, Ruff Y, Moulin E, Giuseppone N. Supramolecular self-assemblies as functional nanomaterials. NANOSCALE 2013; 5:7098-140. [PMID: 23832165 DOI: 10.1039/c3nr02176a] [Citation(s) in RCA: 494] [Impact Index Per Article: 44.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In this review, we survey the diversity of structures and functions which are encountered in advanced self-assembled nanomaterials. We highlight their flourishing implementations in three active domains of applications: biomedical sciences, information technologies, and environmental sciences. Our main objective is to provide the reader with a concise and straightforward entry to this broad field by selecting the most recent and important research articles, supported by some more comprehensive reviews to introduce each topic. Overall, this compilation illustrates how, based on the rules of supramolecular chemistry, the bottom-up approach to design functional objects at the nanoscale is currently producing highly sophisticated materials oriented towards a growing number of applications with high societal impact.
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Affiliation(s)
- Eric Busseron
- SAMS Research Group, University of Strasbourg, Institut Charles Sadron, CNRS, 23 rue du Loess, BP 84087, 67034 Strasbourg Cedex 2, France
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18
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Noshiro D, Sonomura K, Yu HH, Imanishi M, Asami K, Futaki S. Construction of a Ca(2+)-gated artificial channel by fusing alamethicin with a calmodulin-derived extramembrane segment. Bioconjug Chem 2013; 24:188-95. [PMID: 23272973 DOI: 10.1021/bc300468x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Using native chemical ligation, we constructed a Ca(2+)-gated fusion channel protein consisting of alamethicin and the C-terminal domain of calmodulin. At pH 5.4 and in the absence of Ca(2+), this fusion protein yielded a burst-like channel current with no discrete channel conductance levels. However, Ca(2+) significantly lengthened the specific channel open state and increased the mean channel current, while Mg(2+) produced no significant changes in the channel current. On the basis of 8-anilinonaphthalene-1-sulfonic acid (ANS) fluorescent measurement, Ca(2+)-stimulated gating may be related to an increased surface hydrophobicity of the extramembrane segment of the fusion protein.
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Affiliation(s)
- Daisuke Noshiro
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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19
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Noshiro D, Asami K, Futaki S. Control of leakage activities of alamethicin analogs by metals: Side chain-dependent adverse gating response to Zn2+. Bioorg Med Chem 2012; 20:6870-6. [DOI: 10.1016/j.bmc.2012.09.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 09/16/2012] [Accepted: 09/17/2012] [Indexed: 10/27/2022]
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Hjørringgaard CU, Vad BS, Matchkov VV, Nielsen SB, Vosegaard T, Nielsen NC, Otzen DE, Skrydstrup T. Cyclodextrin-scaffolded alamethicin with remarkably efficient membrane permeabilizing properties and membrane current conductance. J Phys Chem B 2012; 116:7652-9. [PMID: 22676384 DOI: 10.1021/jp2098679] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Bacterial resistance to classical antibiotics is a serious medical problem, which continues to grow. Small antimicrobial peptides represent a potential solution and are increasingly being developed as novel therapeutic agents. Many of these peptides owe their antibacterial activity to the formation of trans-membrane ion-channels resulting in cell lysis. However, to further develop the field of peptide antibiotics, a thorough understanding of their mechanism of action is needed. Alamethicin belongs to a class of peptides called peptaibols and represents one of these antimicrobial peptides. To examine the dynamics of assembly and to facilitate a thorough structural evaluation of the alamethicin ion-channels, we have applied click chemistry for the synthesis of templated alamethicin multimers covalently attached to cyclodextrin-scaffolds. Using oriented circular dichroism, calcein release assays, and single-channel current measurements, the α-helices of the templated multimers were demonstrated to insert into lipid bilayers forming highly efficient and remarkably stable ion-channels.
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Affiliation(s)
- Claudia U Hjørringgaard
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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21
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Murase S, Ishino S, Ishino Y, Tanaka T. Control of enzyme reaction by a designed metal-ion-dependent α-helical coiled-coil protein. J Biol Inorg Chem 2012; 17:791-9. [PMID: 22466407 DOI: 10.1007/s00775-012-0896-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 03/20/2012] [Indexed: 01/01/2023]
Abstract
Regulation of protein function by external stimuli is a fascinating target for de novo design. We have constructed a peptide that assembles into a homotrimer in the presence of metal ions, such as Ni(2+), Cu(2+), and Zn(2+). We fused the peptide construct to the DNA-binding domain (DBD) of the heat shock factor from Saccharomyces cerevisiae, which binds tandem repeats of the heat shock element (HSE). However, the fusion protein bound to the natural three tandem HSEs even in the absence of metal ions, although mainly as the dimerized protein. Using "skipped" HSEs containing six additional nucleotides inserted between two adjacent HSEs, to prevent interactions between the DBDs, we found the fusion protein bound to the new DNA target in a metal-ion-dependent manner, as monitored by a HindIII protection assay. The fusion protein containing two metal binding sites in the metal-ion-controlled domain inhibited RNA transcription by T7 RNA polymerase in the presence of metal ions, in a template containing skipped HSEs downstream of the T7 promoter. The designed protein therefore regulates the functions of the enzyme in a metal-ion-dependent manner.
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Affiliation(s)
- Shigeo Murase
- Department of Material Sciences, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-chou, Nagoya, 466-8555, Japan
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22
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Azuma Y, Imai H, Yoshimura T, Kawabata T, Imanishi M, Futaki S. Dipicolylamine as a unique structural switching element for helical peptides. Org Biomol Chem 2012; 10:6062-8. [DOI: 10.1039/c2ob07118e] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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23
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Zhu B, Li J, Xu D. Porous biomimetic membranes: fabrication, properties and future applications. Phys Chem Chem Phys 2011; 13:10584-92. [PMID: 21512690 DOI: 10.1039/c0cp02757j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A cell membrane is a flexible lipid bilayer with sophisticated functions which dominate the exchange of material, energy and information between the outside and the inside of the cell. In order to understand and imitate these structures and functions, scientists had already developed a variety of mimic membranes which are alike in form based on lipid bilayer and organic channel-molecules. With the rise of nanotechnology, a large number of synthetic nano-devices are widely used to construct porous biomimetic membranes which are alike in spirit instead of the conventional lipid bilayer membranes. This perspective will first introduce several typical methods to fabricate porous biomimetic membranes, and then discuss the "smart" properties and future applications of these membranes in materials transport, energy transformation and signal transduction aspects.
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Affiliation(s)
- Bin Zhu
- Department of Chemistry, Peking University, Beijing 100871, PR China
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24
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Noshiro D, Asami K, Futaki S. Metal-assisted channel stabilization: disposition of a single histidine on the N-terminus of alamethicin yields channels with extraordinarily long lifetimes. Biophys J 2010; 98:1801-8. [PMID: 20441743 DOI: 10.1016/j.bpj.2010.01.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 11/08/2009] [Accepted: 01/04/2010] [Indexed: 10/19/2022] Open
Abstract
Alamethicin, a member of the peptaibol family of antibiotics, is a typical channel-forming peptide with a helical structure. The self-assembly of the peptide in the membranes yields voltage-dependent channels. In this study, three alamethicin analogs possessing a charged residue (His, Lys, or Glu) on their N-termini were designed with the expectation of stabilizing the transmembrane structure. A slight elongation of channel lifetime was observed for the Lys and Glu analogs. On the other hand, extensive stabilization of certain channel open states was observed for the His analog. This stabilization was predominantly observed in the presence of metal ions such as Zn(2+), suggesting that metal coordination with His facilitates the formation of a supramolecular assembly in the membranes. Channel stability was greatly diminished by acetylation of the N-terminal amino group, indicating that the N-terminal amino group also plays an important role in metal coordination.
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Affiliation(s)
- Daisuke Noshiro
- Institute for Chemical Research, Kyoto University, Kyoto, Japan
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25
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Zhu B, Li J, Chen Q, Cao RG, Li J, Xu D. Artificial, switchable K+-gated ion channels based on flow-through titania-nanotube arrays. Phys Chem Chem Phys 2010; 12:9989-92. [DOI: 10.1039/b925961a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Azuma Y, Imanishi M, Yoshimura T, Kawabata T, Futaki S. Cobalt(II)-responsive DNA binding of a GCN4-bZIP protein containing cysteine residues functionalized with iminodiacetic acid. Angew Chem Int Ed Engl 2009; 48:6853-6. [PMID: 19655361 DOI: 10.1002/anie.200902888] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Yusuke Azuma
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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Azuma Y, Imanishi M, Yoshimura T, Kawabata T, Futaki S. Cobalt(II)-Responsive DNA Binding of a GCN4-bZIP Protein Containing Cysteine Residues Functionalized with Iminodiacetic Acid. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200902888] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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28
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Mizuno T, Suzuki K, Imai T, Kitade Y, Furutani Y, Kudou M, Oda M, Kandori H, Tsumoto K, Tanaka T. Manipulation of protein-complex function by using an engineered heterotrimeric coiled-coil switch. Org Biomol Chem 2009. [DOI: 10.1039/b901118h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Taira J, Jelokhani-Niaraki M, Osada S, Kato F, Kodama H. Ion-Channel Formation Assisted by Electrostatic Interhelical Interactions in Covalently Dimerized Amphiphilic Helical Peptides. Biochemistry 2008; 47:3705-14. [DOI: 10.1021/bi702371e] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Junichi Taira
- Department of Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan, Department of Chemistry, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5, Canada, and Department of Applied Biological Science, Faculty of Agriculture, Saga University, Saga 840-8502, Japan
| | - Masoud Jelokhani-Niaraki
- Department of Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan, Department of Chemistry, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5, Canada, and Department of Applied Biological Science, Faculty of Agriculture, Saga University, Saga 840-8502, Japan
| | - Satoshi Osada
- Department of Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan, Department of Chemistry, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5, Canada, and Department of Applied Biological Science, Faculty of Agriculture, Saga University, Saga 840-8502, Japan
| | - Fumio Kato
- Department of Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan, Department of Chemistry, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5, Canada, and Department of Applied Biological Science, Faculty of Agriculture, Saga University, Saga 840-8502, Japan
| | - Hiroaki Kodama
- Department of Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan, Department of Chemistry, Faculty of Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5, Canada, and Department of Applied Biological Science, Faculty of Agriculture, Saga University, Saga 840-8502, Japan
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Mayer M, Semetey V, Gitlin I, Yang J, Whitesides GM. Using ion channel-forming peptides to quantify protein-ligand interactions. J Am Chem Soc 2008; 130:1453-65. [PMID: 18179217 DOI: 10.1021/ja077555f] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper proposes a method for sensing affinity interactions by triggering disruption of self-assembly of ion channel-forming peptides in planar lipid bilayers. It shows that the binding of a derivative of alamethicin carrying a covalently attached sulfonamide ligand to carbonic anhydrase II (CA II) resulted in the inhibition of ion channel conductance through the bilayer. We propose that the binding of the bulky CA II protein (MW approximately 30 kD) to the ion channel-forming peptides (MW approximately 2.5 kD) either reduced the tendency of these peptides to self-assemble into a pore or extracted them from the bilayer altogether. In both outcomes, the interactions between the protein and the ligand lead to a disruption of self-assembled pores. Addition of a competitive inhibitor, 4-carboxybenzenesulfonamide, to the solution released CA II from the alamethicin-sulfonamide conjugate and restored the current flow across the bilayer by allowing reassembly of the ion channels in the bilayer. Time-averaged recordings of the current over discrete time intervals made it possible to quantify this monovalent ligand binding interaction. This method gave a dissociation constant of approximately 2 microM for the binding of CA II to alamethicin-sulfonamide in the bilayer recording chamber: this value is consistent with a value obtained independently with CA II and a related sulfonamide derivative by isothermal titration calorimetry.
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Affiliation(s)
- Michael Mayer
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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Futaki S, Asami K. Ligand-induced extramembrane conformation switch controlling alamethicin assembly and the channel current. Chem Biodivers 2007; 4:1313-22. [PMID: 17589883 DOI: 10.1002/cbdv.200790112] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this review, we describe our approach to creating artificial receptor-channel proteins or sensor systems, using an extramembrane segment conformationally switchable by external stimuli. Alamethicin is known to self-assemble in membranes to form ion channels with various open states. Employment of an alpha-helical leucine-zipper segment resulted in the effective modulation of the association states of alamethicin to produce a single predominant channel-open state. A decrease in the helical content of the extramembrane segments was found to induce a channel-current increase. Therefore, conformational changes in the extramembrane segments induced by the interaction with ligands can be reflected in the current levels.
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Affiliation(s)
- Shiroh Futaki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, Japan.
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Peggion C, Jost M, Baldini C, Formaggio F, Toniolo C. Total syntheses in solution of TOAC-labelled alamethicin F50/5 analogues. Chem Biodivers 2007; 4:1183-99. [PMID: 17589860 DOI: 10.1002/cbdv.200790104] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Total syntheses in solution of a set of four selected analogues of the 19-mer component F50/5 of alamethicin, the most extensively studied among the channel-former peptaibol antibiotics, are planned and reported. All analogues bear three Glu(OMe) residues, replacing the Gln residues at positions 7, 18, and 19 of the naturally occurring compound. Three analogues are mono-labelled with the free-radical-containing amino acid residue TOAC at the strategic positions 1, 8, or 16. The fourth analogue is bis-labelled with the same EPR-active residue at both positions 1 and 16. In the native sequence, all of the positions where TOAC replacements have been introduced are characterized by residues of Aib, the prototype of the class of helicogenic C(alpha)-tetrasubstituted alpha-amino acids. All of the TOAC analogues synthesized exhibit significant membrane-modifying properties.
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Affiliation(s)
- Cristina Peggion
- Institute of Biomolecular Chemistry, Padova Unit, CNR, Department of Chemistry, University of Padova, Padova, Italy
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34
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Kay ER, Leigh DA, Zerbetto F. Synthetic molecular motors and mechanical machines. Angew Chem Int Ed Engl 2007; 46:72-191. [PMID: 17133632 DOI: 10.1002/anie.200504313] [Citation(s) in RCA: 2044] [Impact Index Per Article: 120.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The widespread use of controlled molecular-level motion in key natural processes suggests that great rewards could come from bridging the gap between the present generation of synthetic molecular systems, which by and large rely upon electronic and chemical effects to carry out their functions, and the machines of the macroscopic world, which utilize the synchronized movements of smaller parts to perform specific tasks. This is a scientific area of great contemporary interest and extraordinary recent growth, yet the notion of molecular-level machines dates back to a time when the ideas surrounding the statistical nature of matter and the laws of thermodynamics were first being formulated. Here we outline the exciting successes in taming molecular-level movement thus far, the underlying principles that all experimental designs must follow, and the early progress made towards utilizing synthetic molecular structures to perform tasks using mechanical motion. We also highlight some of the issues and challenges that still need to be overcome.
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Affiliation(s)
- Euan R Kay
- School of Chemistry, University of Edinburgh, The King's Buildings, West Mains Road, Edinburgh EH9 3JJ, UK
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36
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Kay E, Leigh D, Zerbetto F. Synthetische molekulare Motoren und mechanische Maschinen. Angew Chem Int Ed Engl 2007. [DOI: 10.1002/ange.200504313] [Citation(s) in RCA: 587] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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