1
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Jungnickel KEJ, Guelle O, Iguchi M, Dong W, Kotov V, Gabriel F, Debacker C, Dairou J, McCort-Tranchepain I, Laqtom NN, Chan SH, Ejima A, Sato K, Massa López D, Saftig P, Mehdipour AR, Abu-Remaileh M, Gasnier B, Löw C, Damme M. MFSD1 with its accessory subunit GLMP functions as a general dipeptide uniporter in lysosomes. Nat Cell Biol 2024:10.1038/s41556-024-01436-5. [PMID: 38839979 DOI: 10.1038/s41556-024-01436-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 05/07/2024] [Indexed: 06/07/2024]
Abstract
The lysosomal degradation of macromolecules produces diverse small metabolites exported by specific transporters for reuse in biosynthetic pathways. Here we deorphanized the major facilitator superfamily domain containing 1 (MFSD1) protein, which forms a tight complex with the glycosylated lysosomal membrane protein (GLMP) in the lysosomal membrane. Untargeted metabolomics analysis of MFSD1-deficient mouse lysosomes revealed an increase in cationic dipeptides. Purified MFSD1 selectively bound diverse dipeptides, while electrophysiological, isotope tracer and fluorescence-based studies in Xenopus oocytes and proteoliposomes showed that MFSD1-GLMP acts as a uniporter for cationic, neutral and anionic dipeptides. Cryoelectron microscopy structure of the dipeptide-bound MFSD1-GLMP complex in outward-open conformation characterized the heterodimer interface and, in combination with molecular dynamics simulations, provided a structural basis for its selectivity towards diverse dipeptides. Together, our data identify MFSD1 as a general lysosomal dipeptide uniporter, providing an alternative route to recycle lysosomal proteolysis products when lysosomal amino acid exporters are overloaded.
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Affiliation(s)
| | - Océane Guelle
- Saints-Pères Paris Institute for the Neurosciences, Université Paris Cité, Centre National de la Recherche Scientifique, Paris, France
| | - Miharu Iguchi
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering and Medicine for Human Health, Stanford University, Stanford, CA, USA
| | - Wentao Dong
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering and Medicine for Human Health, Stanford University, Stanford, CA, USA
| | - Vadim Kotov
- Centre for Structural Systems Biology, Hamburg, Germany
- European Molecular Biology Laboratory Hamburg, Hamburg, Germany
| | - Florian Gabriel
- Centre for Structural Systems Biology, Hamburg, Germany
- European Molecular Biology Laboratory Hamburg, Hamburg, Germany
| | - Cécile Debacker
- Saints-Pères Paris Institute for the Neurosciences, Université Paris Cité, Centre National de la Recherche Scientifique, Paris, France
| | - Julien Dairou
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Cité, Paris, France
| | - Isabelle McCort-Tranchepain
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, Université Paris Cité, Paris, France
| | - Nouf N Laqtom
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering and Medicine for Human Health, Stanford University, Stanford, CA, USA
| | - Sze Ham Chan
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Akika Ejima
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Kenji Sato
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - David Massa López
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Paul Saftig
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | | | - Monther Abu-Remaileh
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering and Medicine for Human Health, Stanford University, Stanford, CA, USA
| | - Bruno Gasnier
- Saints-Pères Paris Institute for the Neurosciences, Université Paris Cité, Centre National de la Recherche Scientifique, Paris, France.
| | - Christian Löw
- Centre for Structural Systems Biology, Hamburg, Germany.
- European Molecular Biology Laboratory Hamburg, Hamburg, Germany.
| | - Markus Damme
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany.
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2
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Newstead S, Parker J, Deme J, Lichtinger S, Kuteyi G, Biggin P, Lea S. Structural basis for antibiotic transport and inhibition in PepT2, the mammalian proton-coupled peptide transporter. RESEARCH SQUARE 2024:rs.3.rs-4435259. [PMID: 38903084 PMCID: PMC11188089 DOI: 10.21203/rs.3.rs-4435259/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
The uptake and elimination of beta-lactam antibiotics in the human body are facilitated by the proton-coupled peptide transporters PepT1 (SLC15A1) and PepT2 (SLC15A2). The mechanism by which SLC15 family transporters recognize and discriminate between different drug classes and dietary peptides remains unclear, hampering efforts to improve antibiotic pharmacokinetics through targeted drug design and delivery. Here, we present cryo-EM structures of the mammalian proton-coupled peptide transporter, PepT2, in complex with the widely used beta-lactam antibiotics cefadroxil, amoxicillin and cloxacillin. Our structures, combined with pharmacophore mapping, molecular dynamics simulations and biochemical assays, establish the mechanism of antibiotic recognition and the important role of protonation in drug binding and transport.
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Affiliation(s)
| | | | - Justin Deme
- National Cancer Institute, National Institutes of Health
| | | | | | | | - Susan Lea
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute
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3
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Selvam B, Chiang N, Shukla D. Energetics of substrate transport in proton-dependent oligopeptide transporters. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.01.592129. [PMID: 38746282 PMCID: PMC11092630 DOI: 10.1101/2024.05.01.592129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The PepT So transporter mediates the transport of peptides across biological membranes. Despite advancements in structural biology, including cryogenic electron microscopy structures resolving PepT So in different states, the molecular basis of peptide recognition and transport by PepT So is not fully elucidated. In this study, we employed molecular dynamics simulations, Markov State Models (MSMs), and Transition Path Theory (TPT) to investigate the transport mechanism of an alanine-alanine peptide (Ala-Ala) through the PepT So transporter. Our simulations revealed conformational changes and key intermediate states involved in peptide translocation. We observed that the presence of the Ala-Ala peptide substrate lowers the free energy barriers associated with transition to the inward-facing state. Furthermore, we elucidated the proton transport model and analyzed the pharmacophore features of intermediate states, providing insights for rational drug design. These findings highlight the significance of substrate binding in modulating the conformational dynamics of PepT So and identify critical residues that facilitate transport.
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4
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Tu G, Fu T, Zheng G, Xu B, Gou R, Luo D, Wang P, Xue W. Computational Chemistry in Structure-Based Solute Carrier Transporter Drug Design: Recent Advances and Future Perspectives. J Chem Inf Model 2024; 64:1433-1455. [PMID: 38294194 DOI: 10.1021/acs.jcim.3c01736] [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: 02/01/2024]
Abstract
Solute carrier transporters (SLCs) are a class of important transmembrane proteins that are involved in the transportation of diverse solute ions and small molecules into cells. There are approximately 450 SLCs within the human body, and more than a quarter of them are emerging as attractive therapeutic targets for multiple complex diseases, e.g., depression, cancer, and diabetes. However, only 44 unique transporters (∼9.8% of the SLC superfamily) with 3D structures and specific binding sites have been reported. To design innovative and effective drugs targeting diverse SLCs, there are a number of obstacles that need to be overcome. However, computational chemistry, including physics-based molecular modeling and machine learning- and deep learning-based artificial intelligence (AI), provides an alternative and complementary way to the classical drug discovery approach. Here, we present a comprehensive overview on recent advances and existing challenges of the computational techniques in structure-based drug design of SLCs from three main aspects: (i) characterizing multiple conformations of the proteins during the functional process of transportation, (ii) identifying druggability sites especially the cryptic allosteric ones on the transporters for substrates and drugs binding, and (iii) discovering diverse small molecules or synthetic protein binders targeting the binding sites. This work is expected to provide guidelines for a deep understanding of the structure and function of the SLC superfamily to facilitate rational design of novel modulators of the transporters with the aid of state-of-the-art computational chemistry technologies including artificial intelligence.
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Affiliation(s)
- Gao Tu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Tingting Fu
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | | | - Binbin Xu
- Chengdu Sintanovo Biotechnology Co., Ltd., Chengdu 610200, China
| | - Rongpei Gou
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Ding Luo
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Panpan Wang
- College of Chemistry and Pharmaceutical Engineering, Huanghuai University, Zhumadian 463000, China
| | - Weiwei Xue
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
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5
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Xia R, Peng HF, Zhang X, Zhang HS. Comprehensive review of amino acid transporters as therapeutic targets. Int J Biol Macromol 2024; 260:129646. [PMID: 38272411 DOI: 10.1016/j.ijbiomac.2024.129646] [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: 11/24/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024]
Abstract
The solute carrier (SLC) family, with more than 400 membrane-bound proteins, facilitates the transport of a wide array of substrates such as nutrients, ions, metabolites, and drugs across biological membranes. Amino acid transporters (AATs) are membrane transport proteins that mediate transfer of amino acids into and out of cells or cellular organelles. AATs participate in many important physiological functions including nutrient supply, metabolic transformation, energy homeostasis, redox regulation, and neurological regulation. Several AATs have been found to significantly impact the progression of human malignancies, and dysregulation of AATs results in metabolic reprogramming affecting tumor growth and progression. However, current clinical therapies that directly target AATs have not been developed. The purpose of this review is to highlight the structural and functional diversity of AATs, the molecular mechanisms in human diseases such as tumors, kidney diseases, and emerging therapeutic strategies for targeting AATs.
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Affiliation(s)
- Ran Xia
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China
| | - Hai-Feng Peng
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China
| | - Xing Zhang
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China
| | - Hong-Sheng Zhang
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China.
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6
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Körner A, Bazzone A, Wichert M, Barthmes M, Dondapati SK, Fertig N, Kubick S. Unraveling the kinetics and pharmacology of human PepT1 using solid supported membrane-based electrophysiology. Bioelectrochemistry 2024; 155:108573. [PMID: 37748262 DOI: 10.1016/j.bioelechem.2023.108573] [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: 07/17/2023] [Revised: 09/14/2023] [Accepted: 09/15/2023] [Indexed: 09/27/2023]
Abstract
The human Peptide Transporter 1 (hPepT1) is known for its broad substrate specificity and its ability to transport (pro-)drugs. Here, we present an in-depth comprehensive study of hPepT1 and its interactions with various substrates via solid supported membrane-based electrophysiology (SSME). Using hPepT1-containing vesicles, we could not identify any peptide induced pre-steady-state currents, indicating that the recorded peak currents reflect steady-state transport. Electrogenic co-transport of H+/glycylglycine (GlyGly) was observed across a pH range of 5.0 to 9.0. The pH dependence is described by a bell-shaped activity curve and two pK values. KM and relative Vmax values of various canonical and non-canonical peptide substrates were contextualized with current mechanistic understandings of hPepT1. Finally, specific inhibition was observed for various inhibitors in a high throughput format, and IC50 values are reported. Taken together, these findings contribute to promoting the design and analysis of pharmacologically relevant substances.
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Affiliation(s)
- Alexander Körner
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany; Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Andre Bazzone
- Nanion Technologies GmbH, Ganghoferstr. 70a, 80339 Munich, Germany
| | - Maximilian Wichert
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany; Freie Universität Berlin, Institute of Chemistry and Biochemistry - Biochemistry, 14195 Berlin, Germany
| | - Maria Barthmes
- Nanion Technologies GmbH, Ganghoferstr. 70a, 80339 Munich, Germany
| | - Srujan Kumar Dondapati
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany.
| | - Niels Fertig
- Nanion Technologies GmbH, Ganghoferstr. 70a, 80339 Munich, Germany
| | - Stefan Kubick
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany; Freie Universität Berlin, Institute of Chemistry and Biochemistry - Biochemistry, 14195 Berlin, Germany; Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus - Senftenberg, The Brandenburg Medical School Theodor Fontane and the University of Potsdam, Germany
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7
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Xiang J, Keep RF. Proton-Coupled Oligopeptide Transport (Slc15) in the Brain: Past and Future Research. Pharm Res 2023; 40:2533-2540. [PMID: 37308743 DOI: 10.1007/s11095-023-03550-9] [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: 05/10/2023] [Accepted: 06/06/2023] [Indexed: 06/14/2023]
Abstract
This mini-review describes the role of the solute carrier (SLC)15 family of proton-coupled oligopeptide transporters (POTs) and particularly Pept2 (Slc15A2) and PhT1 (Slc15A4) in the brain. That family transports endogenous di- and tripeptides and peptidomimetics but also a number of drugs. The review focuses on the pioneering work of David E. Smith in the field in identifying the impact of PepT2 at the choroid plexus (the blood-CSF barrier) as well as PepT2 and PhT1 in brain parenchymal cells. It also discusses recent findings and future directions in relation to brain POTs including cellular and subcellular localization, regulatory pathways, transporter structure, species differences and disease states.
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Affiliation(s)
- Jianming Xiang
- Department of Neurosurgery, University of Michigan, R5018 BSRB 109 Zina Pitcher Place, Ann Arbor, MI, 48109, USA
| | - Richard F Keep
- Department of Neurosurgery, University of Michigan, R5018 BSRB 109 Zina Pitcher Place, Ann Arbor, MI, 48109, USA.
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8
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Remm S, De Vecchis D, Schöppe J, Hutter CAJ, Gonda I, Hohl M, Newstead S, Schäfer LV, Seeger MA. Structural basis for triacylglyceride extraction from mycobacterial inner membrane by MFS transporter Rv1410. Nat Commun 2023; 14:6449. [PMID: 37833269 PMCID: PMC10576003 DOI: 10.1038/s41467-023-42073-0] [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: 12/14/2022] [Accepted: 09/28/2023] [Indexed: 10/15/2023] Open
Abstract
Mycobacterium tuberculosis is protected from antibiotic therapy by a multi-layered hydrophobic cell envelope. Major facilitator superfamily (MFS) transporter Rv1410 and the periplasmic lipoprotein LprG are involved in transport of triacylglycerides (TAGs) that seal the mycomembrane. Here, we report a 2.7 Å structure of a mycobacterial Rv1410 homologue, which adopts an outward-facing conformation and exhibits unusual transmembrane helix 11 and 12 extensions that protrude ~20 Å into the periplasm. A small, very hydrophobic cavity suitable for lipid transport is constricted by a functionally important ion-lock likely involved in proton coupling. Combining mutational analyses and MD simulations, we propose that TAGs are extracted from the core of the inner membrane into the central cavity via lateral clefts present in the inward-facing conformation. The functional role of the periplasmic helix extensions is to channel the extracted TAG into the lipid binding pocket of LprG.
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Affiliation(s)
- Sille Remm
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Dario De Vecchis
- Center for Theoretical Chemistry, Ruhr University Bochum, Bochum, Germany
| | - Jendrik Schöppe
- Institute of Biochemistry, University of Zurich, Zürich, Switzerland
- Global Research Technologies, Novo Nordisk A/S, Måløv, Denmark
| | - Cedric A J Hutter
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
- Linkster Therapeutics, Zürich, Switzerland
| | - Imre Gonda
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Michael Hohl
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
- Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Simon Newstead
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, United Kingdom
| | - Lars V Schäfer
- Center for Theoretical Chemistry, Ruhr University Bochum, Bochum, Germany.
| | - Markus A Seeger
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland.
- National Center for Mycobacteria, Zurich, Switzerland.
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9
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Kotov V, Killer M, Jungnickel KEJ, Lei J, Finocchio G, Steinke J, Bartels K, Strauss J, Dupeux F, Humm AS, Cornaciu I, Márquez JA, Pardon E, Steyaert J, Löw C. Plasticity of the binding pocket in peptide transporters underpins promiscuous substrate recognition. Cell Rep 2023; 42:112831. [PMID: 37467108 DOI: 10.1016/j.celrep.2023.112831] [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: 02/15/2023] [Revised: 06/09/2023] [Accepted: 07/03/2023] [Indexed: 07/21/2023] Open
Abstract
Proton-dependent oligopeptide transporters (POTs) are promiscuous transporters of the major facilitator superfamily that constitute the main route of entry for a wide range of dietary peptides and orally administrated peptidomimetic drugs. Given their clinical and pathophysiological relevance, several POT homologs have been studied extensively at the structural and molecular level. However, the molecular basis of recognition and transport of diverse peptide substrates has remained elusive. We present 14 X-ray structures of the bacterial POT DtpB in complex with chemically diverse di- and tripeptides, providing novel insights into the plasticity of the conserved central binding cavity. We analyzed binding affinities for more than 80 peptides and monitored uptake by a fluorescence-based transport assay. To probe whether all 8400 natural di- and tripeptides can bind to DtpB, we employed state-of-the-art molecular docking and machine learning and conclude that peptides with compact hydrophobic residues are the best DtpB binders.
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Affiliation(s)
- Vadim Kotov
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany
| | - Maxime Killer
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany; Faculty of Biosciences, Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Hamburg, Germany
| | - Katharina E J Jungnickel
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany
| | - Jian Lei
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany; State Key Laboratory of Biotherapy and Cancer Center, Sichuan University, No. 17, Block 3, Southern Renmin Road, Chengdu, Sichuan 610041, People's Republic of China
| | - Giada Finocchio
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany
| | - Josi Steinke
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany
| | - Kim Bartels
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany
| | - Jan Strauss
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany
| | - Florine Dupeux
- European Molecular Biology Laboratory (EMBL) Grenoble, 71 Avenue des Martyrs CS 90181, 38042 Grenoble Cedex 9, France
| | - Anne-Sophie Humm
- European Molecular Biology Laboratory (EMBL) Grenoble, 71 Avenue des Martyrs CS 90181, 38042 Grenoble Cedex 9, France
| | - Irina Cornaciu
- European Molecular Biology Laboratory (EMBL) Grenoble, 71 Avenue des Martyrs CS 90181, 38042 Grenoble Cedex 9, France
| | - José A Márquez
- European Molecular Biology Laboratory (EMBL) Grenoble, 71 Avenue des Martyrs CS 90181, 38042 Grenoble Cedex 9, France
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium; VIB-VUB Center for Structural Biology, VIB, 1050 Brussels, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium; VIB-VUB Center for Structural Biology, VIB, 1050 Brussels, Belgium
| | - Christian Löw
- Center for Structural Systems Biology (CSSB), Notkestraße 85, 22607 Hamburg, Germany; European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607 Hamburg, Germany.
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10
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Katsube S, Willibal K, Vemulapally S, Hariharan P, Tikhonova E, Pardon E, Kaback HR, Steyaert J, Guan L. In vivo and in vitro characterizations of melibiose permease (MelB) conformation-dependent nanobodies reveal sugar-binding mechanisms. J Biol Chem 2023; 299:104967. [PMID: 37380079 PMCID: PMC10374971 DOI: 10.1016/j.jbc.2023.104967] [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: 02/13/2023] [Revised: 06/13/2023] [Accepted: 06/19/2023] [Indexed: 06/30/2023] Open
Abstract
Salmonella enterica serovar Typhimurium melibiose permease (MelBSt) is a prototype of the Na+-coupled major facilitator superfamily transporters, which are important for the cellular uptake of molecules including sugars and small drugs. Although the symport mechanisms have been well-studied, mechanisms of substrate binding and translocation remain enigmatic. We have previously determined the sugar-binding site of outward-facing MelBSt by crystallography. To obtain other key kinetic states, here we raised camelid single-domain nanobodies (Nbs) and carried out a screening against the WT MelBSt under 4 ligand conditions. We applied an in vivo cAMP-dependent two-hybrid assay to detect interactions of Nbs with MelBSt and melibiose transport assays to determine the effects on MelBSt functions. We found that all selected Nbs showed partial to complete inhibitions of MelBSt transport activities, confirming their intracellular interactions. A group of Nbs (714, 725, and 733) was purified, and isothermal titration calorimetry measurements showed that their binding affinities were significantly inhibited by the substrate melibiose. When titrating melibiose to the MelBSt/Nb complexes, Nb also inhibited the sugar-binding. However, the Nb733/MelBSt complex retained binding to the coupling cation Na+ and also to the regulatory enzyme EIIAGlc of the glucose-specific phosphoenolpyruvate/sugar phosphotransferase system. Further, EIIAGlc/MelBSt complex also retained binding to Nb733 and formed a stable supercomplex. All data indicated that MelBSt trapped by Nbs retained its physiological functions and the trapped conformation is similar to that bound by the physiological regulator EIIAGlc. Therefore, these conformational Nbs can be useful tools for further structural, functional, and conformational analyses.
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Affiliation(s)
- Satoshi Katsube
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Katleen Willibal
- VIB Center for Structural Biology Research, VIB, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - Sangama Vemulapally
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Parameswaran Hariharan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Elena Tikhonova
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Els Pardon
- VIB Center for Structural Biology Research, VIB, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - H Ronald Kaback
- Department of Physiology and Department of Microbiology, Immunology, and Molecular Genetics, Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - Jan Steyaert
- VIB Center for Structural Biology Research, VIB, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - Lan Guan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA.
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11
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Omori A, Sasaki S, Kikukawa T, Shimono K, Miyauchi S. Elucidation of a Thermodynamical Feature Attributed to Substrate Binding to the Prokaryotic H +/Oligopeptide Cotransporter YdgR with Calorimetric Analysis: The Substrate Binding Driven by the Change in Entropy Implies the Release of Bound Water Molecules from the Binding Pocket. Biochemistry 2023. [PMID: 37163674 DOI: 10.1021/acs.biochem.2c00673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Here, we have elucidated the substrate recognition mechanism by a prokaryotic H+/oligopeptide cotransporter, YdgR, using isothermal titration calorimetry. Under acidic conditions (pH 6.0), the binding of a dipeptide, Val-Ala, to YdgR elicited endothermic enthalpy, which compensated for the increase in entropy due to dipeptide binding. A series of dipeptides were used in the binding titration. The dipeptides represent Val-X and X-Val, where X is Ala, Ser, Val, Tyr, or Phe. Most dipeptides revealed endothermic enthalpy, which was completely compensated by the increase in entropy due to dipeptide binding. The change in enthalpy due to binding correlated well with the change in entropy, whereas the Gibbs free energy involved in the binding of the dipeptide to YdgR remained unchanged irrespective of dipeptide sequences, implying that the binding reaction was driven by entropy, that is, the release of bound water molecules in the binding pocket. It is also important to clarify that, based on the prediction of water molecules in the ligand-binding pocket of YdgR, the release of three bound water molecules in the putative substrate binding pocket occurred through binding to YdgR. In the comparison of Val-X and X-Val dipeptides, the N-terminal region of the binding pocket might contain more bound water molecules than the C-terminal region. In light of these findings, we suggest that bound water molecules might play an important role in substrate recognition and binding by YdgR.
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Affiliation(s)
- Akiko Omori
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Shotaro Sasaki
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Takashi Kikukawa
- Faculty of Advanced Life Science, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo 060-0810, Japan
| | - Kazumi Shimono
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
- Faculty of Pharmaceutical Sciences, Sojo University, 4-22-1 Ikeda Nishi-ku, Kumamoto 860-0082, Japan
| | - Seiji Miyauchi
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
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12
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Gharabli H, Rafiq M, Iqbal A, Yan R, Aduri NG, Sharma N, Prabhala BK, Mirza O. Functional Characterization of the Putative POT from Clostridium perfringens. BIOLOGY 2023; 12:biology12050651. [PMID: 37237465 DOI: 10.3390/biology12050651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/28/2023]
Abstract
Proton-coupled oligopeptide transporters (POTs) are a fundamental part of the cellular transport machinery that provides plants, bacteria, and mammals with nutrition in the form of short peptides. However, POTs are not restricted to peptide transport; mammalian POTs have especially been in focus due to their ability to transport several peptidomimetics in the small intestine. Herein, we studied a POT from Clostridium perfringens (CPEPOT), which unexpectedly exhibited atypical characteristics. First, very little uptake of a fluorescently labelled peptide β-Ala-Lys-AMCA, an otherwise good substrate of several other bacterial POTs, was observed. Secondly, in the presence of a competitor peptide, enhanced uptake of β-Ala-Lys-AMCA was observed due to trans-stimulation. This effect was also observed even in the absence of a proton electrochemical gradient, suggesting that β-Ala-Lys-AMCA uptake mediated by CPEPOT is likely through the substrate-concentration-driving exchange mechanism, unlike any other functionally characterized bacterial POTs.
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Affiliation(s)
- Hani Gharabli
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Maria Rafiq
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Anna Iqbal
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Ruyu Yan
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Nanda G Aduri
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Neha Sharma
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Bala K Prabhala
- Department of Physics, Chemistry and Pharmacy, Faculty of Science, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark
| | - Osman Mirza
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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13
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Tu G, Xu B, Luo D, Liu J, Liu Z, Chen G, Xue W. Multi-state Model-Based Identification of Cryptic Allosteric Sites on Human Serotonin Transporter. ACS Chem Neurosci 2023; 14:1686-1694. [PMID: 37067527 DOI: 10.1021/acschemneuro.3c00155] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2023] Open
Abstract
Serotonin transporter (SERT) plays a fundamental role in taking the synaptic cleft serotonin back to the presynaptic neuron. The discovery of allosteric SERT modulators represents the next-generation medication for psychiatric disorders such as depression. Here, based on the cryo-EM structures of ibogaine in complex with SERT in distinct conformations, the multiple functional structures of the transporter bound to serotonin, including outward-open (OOholo), outward-occluded (OCholo), and inward-open (IOholo and IOholo'), were carefully characterized by induced-fit docking Gaussian-accelerated molecular dynamics (IFD-GaMD) simulation and the free-energy landscape analysis. Further MM/GBSA binding free energy, per-residue contribution, and molecular interaction fingerprint calculations revealed the interaction variations of serotonin with SERT in functional structures, which confirmed the allostery of SERT during serotonin reuptake. Moreover, five unique cryptic allosteric sites, which are druggable and capable of targeting by small molecules, were identified on the characterized multistate structures. These results provide structural and energetic information for the molecular mechanism of serotonin reuptake and will provide opportunities for the development of novel therapeutics based on the identified new allosteric sites on SERT.
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Affiliation(s)
- Gao Tu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Binbin Xu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Ding Luo
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Jin Liu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Zerong Liu
- Central Nervous System Drug Key Laboratory of Sichuan Province, Sichuan Credit Pharmaceutical CO., Ltd., Luzhou 646000, China
| | - Gang Chen
- Central Nervous System Drug Key Laboratory of Sichuan Province, Sichuan Credit Pharmaceutical CO., Ltd., Luzhou 646000, China
| | - Weiwei Xue
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
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14
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Chen HH, Wang YX, Li DF, Liu C, Bi SY, Jiang CY, Liu SJ. Chemoreceptors from the commensal gut Roseburia rectibacter bind to mucin and trigger chemotaxis. Environ Microbiol 2023. [PMID: 36869629 DOI: 10.1111/1462-2920.16365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 03/02/2023] [Indexed: 03/05/2023]
Abstract
Chemotaxis is crucial for bacterial adherence and colonization of the host gastrointestinal tract. Previous studies have demonstrated that chemotaxis affects the virulence of causative pathogens and the infection in the host. However, the chemotactic abilities of non-pathogenic and commensal gut bacteria have rarely been explored. We observed that Roseburia rectibacter NSJ-69 exhibited flagella-dependent motility and chemotaxis to a variety of molecules, including mucin and propionate. A genome-wide analysis revealed that NSJ-69 has 28 putative chemoreceptors, 15 of which have periplasmic ligand-binding domains (LBDs). These LBD-coding genes were chemically synthesized and expressed heterologously in Escherichia coli. Intensive screening of ligands revealed four chemoreceptors bound to mucin and two bound to propionate. When expressed in Comamonas testosteroni or E. coli, these chemoreceptors elicited chemotaxis toward mucin and propionate. Hybrid chemoreceptors were constructed, and results showed that the chemotactic responses to mucin and propionate were dependent on the LBDs of R. rectibacter chemoreceptors. Our study identified and characterized R. rectibacter chemoreceptors. These results will facilitate further investigations on the involvement of microbial chemotaxis in host colonization.
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Affiliation(s)
- Hong-He Chen
- State Key Laboratory of Microbial Resources, and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Yu-Xin Wang
- State Key Laboratory of Microbial Biotechnology, Shandong University, Qingdao, People's Republic of China
| | - De-Feng Li
- State Key Laboratory of Microbial Resources, and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Chang Liu
- State Key Laboratory of Microbial Resources, and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.,State Key Laboratory of Microbial Biotechnology, Shandong University, Qingdao, People's Republic of China
| | - Shuang-Yu Bi
- State Key Laboratory of Microbial Biotechnology, Shandong University, Qingdao, People's Republic of China
| | - Cheng-Ying Jiang
- State Key Laboratory of Microbial Resources, and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Shuang-Jiang Liu
- State Key Laboratory of Microbial Resources, and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.,State Key Laboratory of Microbial Biotechnology, Shandong University, Qingdao, People's Republic of China
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15
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Li Y, Ge X. Role of Berberine as a Potential Efflux Pump Inhibitor against MdfA from Escherichia coli: In Vitro and In Silico Studies. Microbiol Spectr 2023; 11:e0332422. [PMID: 36786641 PMCID: PMC10100983 DOI: 10.1128/spectrum.03324-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 01/30/2023] [Indexed: 02/15/2023] Open
Abstract
Infections by Gram-negative pathogens are usually difficult to manage due to the drug export by efflux pumps. With the evolution and horizontal transfer of efflux pumps, there is an urgent need to discover safe and effective efflux pump inhibitors. Here, we found that the natural compound berberine (BBR), a traditional medicine for intestinal infection, is an inhibitor against the major facilitator superfamily (MFS) efflux pump MdfA in Escherichia coli. The impact of BBR on MdfA was evaluated in a recombinant E. coli reporter strain. We demonstrated that low levels of BBR significantly increased intracellular ciprofloxacin concentrations and restored antibiotic susceptibility of the reporter strain. At the same time, we conducted molecular dynamics simulations to investigate the mechanisms of BBR's effect on MdfA. Our data indicated that BBR can aggregate to the periplasmic and cytoplasmic sides of MdfA in both of its inward and outward conformations. Protein rigidities were affected to different degrees. More importantly, two major driving forces for the conformational transition, salt bridges and hydrophilic interactions with water, were changed by BBR's aggregation to MdfA, which affected its conformational transition. In summary, our data provide evidence for the extended application of BBR as an efflux pump inhibitor at a clinically meaningful level. We also reveal the mechanisms and provide insights into BBR's effect on the reciprocal motion of MdfA. IMPORTANCE In this work, we evaluated the role of berberine (BBR) as an inhibitor of the MFS efflux pump MdfA from E. coli. We demonstrated that low levels of BBR significantly increased intracellular ciprofloxacin concentrations and restored antibiotic susceptibility of the reporter strain. Molecular dynamics simulations revealed the effect of BBR on the conformational transition of MdfA. Our data suggested that driving forces for MdfA's conformational transition were affected by BBR and provided evidence for BBR's extended application as an effective inhibitor of MdfA.
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Affiliation(s)
- Ying Li
- College of Biochemical Engineering, Beijing Union University, Beijing, China
| | - Xizhen Ge
- College of Biochemical Engineering, Beijing Union University, Beijing, China
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16
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Gyimesi G, Hediger MA. Transporter-Mediated Drug Delivery. Molecules 2023; 28:molecules28031151. [PMID: 36770817 PMCID: PMC9919865 DOI: 10.3390/molecules28031151] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/12/2023] [Accepted: 01/18/2023] [Indexed: 01/27/2023] Open
Abstract
Transmembrane transport of small organic and inorganic molecules is one of the cornerstones of cellular metabolism. Among transmembrane transporters, solute carrier (SLC) proteins form the largest, albeit very diverse, superfamily with over 400 members. It was recognized early on that xenobiotics can directly interact with SLCs and that this interaction can fundamentally determine their efficacy, including bioavailability and intertissue distribution. Apart from the well-established prodrug strategy, the chemical ligation of transporter substrates to nanoparticles of various chemical compositions has recently been used as a means to enhance their targeting and absorption. In this review, we summarize efforts in drug design exploiting interactions with specific SLC transporters to optimize their therapeutic effects. Furthermore, we describe current and future challenges as well as new directions for the advanced development of therapeutics that target SLC transporters.
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17
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Li Y, Ge X. Molecular Dynamics Investigation of MFS Efflux Pump MdfA Reveals an Intermediate State between Its Inward and Outward Conformations. Int J Mol Sci 2022; 24:ijms24010356. [PMID: 36613823 PMCID: PMC9820426 DOI: 10.3390/ijms24010356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022] Open
Abstract
Multidrug resistance poses a major challenge to antibiotic therapy. A principal cause of antibiotic resistance is through active export by efflux pumps embedded in the bacterial membrane. Major facilitator superfamily (MFS) efflux pumps constitute a major group of transporters, which are often related to quinolone resistance in clinical settings. Although a rocker-switch model is proposed for description of their conformational transitions, detailed changes in this process remain poorly understood. Here we used MdfA from E. coli as a representative MFS efflux pump to investigate factors that can affect its conformational transition in silico. Molecular dynamics (MD) simulations of MdfA's inward and outward conformations revealed an intermediate state between these two conformations. By comparison of the subtle differences between the intermediate state and the average state, we indicated that conformational transition from outward to inward was initiated by protonation of the periplasmic side. Subsequently, hydrophilic interaction of the periplasmic side with water was promoted and the regional structure of helix 1 was altered to favor this process. As the hydrophobic interaction between MdfA and membrane was also increased, energy was concentrated and stored for the opposite transition. In parallel, salt bridges at the cytoplasmic side were altered to lower probabilities to facilitate the entrance of substrate. In summary, we described the total and local changes during MdfA's conformational transition, providing insights for the development of potential inhibitors.
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Affiliation(s)
| | - Xizhen Ge
- Correspondence: ; Tel.: +86-10-5207-2337
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18
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Li Y, Ge X. Enhanced internal ionic interaction of MFS efflux pump MdfA contributes to its elevated antibiotic export. Phys Chem Chem Phys 2022; 25:788-795. [PMID: 36510750 DOI: 10.1039/d2cp05059e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Infections caused by Gram-negative pathogens are difficult to manage due to their antibiotic resistance. Efflux pumps, which transport intracellular toxins out of the cytoplasm, play an important role in the detoxification of bacteria when treated with antibiotics. The major facilitator superfamily (MFS) is a kind of widely distributed efflux pumps and can actively export clinically important antibiotics such as ciprofloxacin, while the role of internal ionic interactions in regulating drug export remains poorly understood. Herein we used a representative MFS efflux pump MdfA to investigate the impact of internal ionic interactions on the antibiotic resistance of E. coli. First, we identified the internal salt bridges of MdfA and searched their natural variants across all the sequenced E. coli isolates. By constructing these variants, we discovered that extending the salt bridge on the cytoplasmic side (E136D) conferred an elevated antibiotic resistance level of E. coli, and the level was further enhanced by combining it with an artificial mutation K346R. By analyzing the trajectories of MdfA's variants in molecular dynamics (MD) simulations, we revealed that ionic interaction strengths on the two sides were proportionally enhanced, while the protein flexibility was not affected. Moreover, enhanced interactions resulted in a larger surface for MdfA's protonation, suggesting a higher possibility for its activation. Collectively, our data revealed the importance of internal interactions on the drug export of MdfA, offering insights for the development of novel inhibitors against MFS efflux pumps.
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Affiliation(s)
- Ying Li
- College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China.
| | - Xizhen Ge
- College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China.
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19
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Killer M, Finocchio G, Mertens HDT, Svergun DI, Pardon E, Steyaert J, Löw C. Cryo-EM Structure of an Atypical Proton-Coupled Peptide Transporter: Di- and Tripeptide Permease C. Front Mol Biosci 2022; 9:917725. [PMID: 35898305 PMCID: PMC9309889 DOI: 10.3389/fmolb.2022.917725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 06/16/2022] [Indexed: 11/16/2022] Open
Abstract
Proton-coupled Oligopeptide Transporters (POTs) of the Major Facilitator Superfamily (MFS) mediate the uptake of short di- and tripeptides in all phyla of life. POTs are thought to constitute the most promiscuous class of MFS transporters, with the potential to transport more than 8400 unique substrates. Over the past two decades, transport assays and biophysical studies have shown that various orthologues and paralogues display differences in substrate selectivity. The E. coli genome codes for four different POTs, known as Di- and tripeptide permeases A-D (DtpA-D). DtpC was shown previously to favor positively charged peptides as substrates. In this study, we describe, how we determined the structure of the 53 kDa DtpC by cryogenic electron microscopy (cryo-EM), and provide structural insights into the ligand specificity of this atypical POT. We collected and analyzed data on the transporter fused to split superfolder GFP (split sfGFP), in complex with a 52 kDa Pro-macrobody and with a 13 kDa nanobody. The latter sample was more stable, rigid and a significant fraction dimeric, allowing us to reconstruct a 3D volume of DtpC at a resolution of 2.7 Å. This work provides a molecular explanation for the selectivity of DtpC, and highlights the value of small and rigid fiducial markers such as nanobodies for structure determination of low molecular weight integral membrane proteins lacking soluble domains.
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Affiliation(s)
- Maxime Killer
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit C/o Deutsches Elektronen Synchrotron (DESY), Hamburg, Germany
- Collaboration for Joint PhD Degree Between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Giada Finocchio
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit C/o Deutsches Elektronen Synchrotron (DESY), Hamburg, Germany
| | - Haydyn D. T. Mertens
- Molecular Biology Laboratory (EMBL), Hamburg Unit C/o Deutsches Elektronen Synchrotron (DESY), Hamburg, Germany
| | - Dmitri I. Svergun
- Molecular Biology Laboratory (EMBL), Hamburg Unit C/o Deutsches Elektronen Synchrotron (DESY), Hamburg, Germany
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
- VIB-VUB Center for Structural Biology, VIB, Brussels, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
- VIB-VUB Center for Structural Biology, VIB, Brussels, Belgium
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit C/o Deutsches Elektronen Synchrotron (DESY), Hamburg, Germany
- *Correspondence: Christian Löw,
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20
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Li Y, Ge X. Discovering interrelated natural mutations of efflux pump
KmrA
from
Klebsiella pneumoniae
that confer increased multidrug resistance. Protein Sci 2022; 31:e4323. [DOI: 10.1002/pro.4323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/03/2022] [Accepted: 04/11/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Ying Li
- College of Biochemical Engineering Beijing Union University Beijing China
| | - Xizhen Ge
- College of Biochemical Engineering Beijing Union University Beijing China
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21
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Li Y, Wen H, Ge X. Opposite motion of the Central Helices of efflux pump KmrA is important for its export efficiency. Microb Pathog 2022; 167:105570. [PMID: 35550844 DOI: 10.1016/j.micpath.2022.105570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 04/11/2022] [Accepted: 05/05/2022] [Indexed: 10/18/2022]
Abstract
Efflux pump of Major Facilitator Superfamily (MFS) is widely distributed in bacteria, while its role in regulating antibiotic resistance of nosocomial pathogen Klebsiella pneumoniae remains unclear. Herein we analyzed the effect of amino acid substitution of MFS efflux pump KmrA on its export efficiency via molecular biology and molecular dynamics (MD). After searching across the 804 sequenced K. pneumoniae isolates, we identified four major variants of KmrA, while one of them KmrA-A was demonstrated an inactive one in MIC and ethidium bromide efflux assays. Subsequently, MD simulations of KmrA and its variants were conducted and the opposite motion of the central helices were observed for the active variants, while it was not found for KmrA-A. To further identify the importance of the opposite motion to the conformational transition, we calculated their differences in volume of binding pocket, salt bridge and hydrophilic interaction with water based on the rocker-switch model. Our results indicated that the opposite motion of KmrA conferred a larger binding pocket and stronger hydrogen bond with water at inward-facing conformation. An unusual substitution S374A of KmrA-A disrupted the normal motion of central helices by enhancing hydrophobic interactions between them, resulting into the altered positions and strengths of salt bridge, which was deduced to affect the conformational transition. Overall our data provided detailed information on the regular of KmrA's moving trajectory, demonstrating the importance of opposite motion of central helices to KmrA's export efficiency.
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Affiliation(s)
- Ying Li
- College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China
| | - Honglin Wen
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Xizhen Ge
- College of Biochemical Engineering, Beijing Union University, Beijing, 100023, China.
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22
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Extracellular domain of PepT1 interacts with TM1 to facilitate substrate transport. Structure 2022; 30:1035-1041.e3. [PMID: 35580608 PMCID: PMC10404463 DOI: 10.1016/j.str.2022.04.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/07/2022] [Accepted: 04/21/2022] [Indexed: 11/20/2022]
Abstract
Mammalian peptide transporters, PepT1 and PepT2, mediate uptake of small peptides and are essential for their absorption. PepT also mediates absorption of many drugs and prodrugs to enhance their bioavailability. PepT has twelve transmembrane (TM) helices that fold into an N-terminal domain (NTD, TM1-6) and a C-terminal domain (CTD, TM7-12) and has a large extracellular domain (ECD) between TM9-10. It is well recognized that peptide transport requires movements of the NTD and CTD, but the role of the ECD in PepT1 remains unclear. Here we report the structure of horse PepT1 encircled in lipid nanodiscs and captured in the inward-open apo conformation. The structure shows that the ECD bridges the NTD and CTD by interacting with TM1. Deletion of ECD or mutations to the ECD-TM1 interface impairs the transport activity. These results demonstrate an important role of ECD in PepT1 and enhance our understanding of the transport mechanism in PepT1.
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23
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Stauffer M, Jeckelmann JM, Ilgü H, Ucurum Z, Boggavarapu R, Fotiadis D. Peptide transporter structure reveals binding and action mechanism of a potent PEPT1 and PEPT2 inhibitor. Commun Chem 2022; 5:23. [PMID: 36697632 PMCID: PMC9814568 DOI: 10.1038/s42004-022-00636-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/27/2022] [Indexed: 01/28/2023] Open
Abstract
Inhibitors for membrane transporters have been shown to be indispensable as drugs and tool compounds. The proton-dependent oligopeptide transporters PEPT1 and PEPT2 from the SLC15 family play important roles in human and mammalian physiology. With Lys[Z(NO2)]-Val (LZNV), a modified Lys-Val dipeptide, a potent transport inhibitor for PEPT1 and PEPT2 is available. Here we present the crystal structure of the peptide transporter YePEPT in complex with LZNV. The structure revealed the molecular interactions for inhibitor binding and a previously undescribed mostly hydrophobic pocket, the PZ pocket, involved in interaction with LZNV. Comparison with a here determined ligand-free structure of the transporter unveiled that the initially absent PZ pocket emerges through conformational changes upon inhibitor binding. The provided biochemical and structural information constitutes an important framework for the mechanistic understanding of inhibitor binding and action in proton-dependent oligopeptide transporters.
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Affiliation(s)
- Mirko Stauffer
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Jean-Marc Jeckelmann
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Hüseyin Ilgü
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Zöhre Ucurum
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Rajendra Boggavarapu
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland ,grid.67105.350000 0001 2164 3847Present Address: Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH USA
| | - Dimitrios Fotiadis
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
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24
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Puthenveetil R, Christenson ET, Vinogradova O. New Horizons in Structural Biology of Membrane Proteins: Experimental Evaluation of the Role of Conformational Dynamics and Intrinsic Flexibility. MEMBRANES 2022; 12:227. [PMID: 35207148 PMCID: PMC8877495 DOI: 10.3390/membranes12020227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 02/08/2023]
Abstract
A plethora of membrane proteins are found along the cell surface and on the convoluted labyrinth of membranes surrounding organelles. Since the advent of various structural biology techniques, a sub-population of these proteins has become accessible to investigation at near-atomic resolutions. The predominant bona fide methods for structure solution, X-ray crystallography and cryo-EM, provide high resolution in three-dimensional space at the cost of neglecting protein motions through time. Though structures provide various rigid snapshots, only an amorphous mechanistic understanding can be inferred from interpolations between these different static states. In this review, we discuss various techniques that have been utilized in observing dynamic conformational intermediaries that remain elusive from rigid structures. More specifically we discuss the application of structural techniques such as NMR, cryo-EM and X-ray crystallography in studying protein dynamics along with complementation by conformational trapping by specific binders such as antibodies. We finally showcase the strength of various biophysical techniques including FRET, EPR and computational approaches using a multitude of succinct examples from GPCRs, transporters and ion channels.
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Affiliation(s)
- Robbins Puthenveetil
- Section on Structural and Chemical Biology of Membrane Proteins, Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 35A Convent Dr., Bethesda, MD 20892, USA
| | | | - Olga Vinogradova
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, Storrs, CT 06269, USA
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25
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Killer M, Wald J, Pieprzyk J, Marlovits TC, Löw C. Structural snapshots of human PepT1 and PepT2 reveal mechanistic insights into substrate and drug transport across epithelial membranes. SCIENCE ADVANCES 2021; 7:eabk3259. [PMID: 34730990 PMCID: PMC8565842 DOI: 10.1126/sciadv.abk3259] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The uptake of peptides in mammals plays a crucial role in nutrition and inflammatory diseases. This process is mediated by promiscuous transporters of the solute carrier family 15, which form part of the major facilitator superfamily. Besides the uptake of short peptides, peptide transporter 1 (PepT1) is a highly abundant drug transporter in the intestine and represents a major route for oral drug delivery. PepT2 also allows renal drug reabsorption from ultrafiltration and brain-to-blood efflux of neurotoxic compounds. Here, we present cryogenic electron microscopy (cryo-EM) structures of human PepT1 and PepT2 captured in four different states throughout the transport cycle. The structures reveal the architecture of human peptide transporters and provide mechanistic insights into substrate recognition and conformational transitions during transport. This may support future drug design efforts to increase the bioavailability of different drugs in the human body.
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Affiliation(s)
- Maxime Killer
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607 Hamburg, Germany
- European Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, Faculty of Biosciences, Im Neuenheimer Feld 234, D-69120 Heidelberg, Germany
| | - Jiri Wald
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607 Hamburg, Germany
- Institute of Structural and Systems Biology, University Medical Center Hamburg-Eppendorf, Notkestrasse 85, D-22607 Hamburg, Germany
- Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
| | - Joanna Pieprzyk
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607 Hamburg, Germany
- European Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
| | - Thomas C. Marlovits
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607 Hamburg, Germany
- Institute of Structural and Systems Biology, University Medical Center Hamburg-Eppendorf, Notkestrasse 85, D-22607 Hamburg, Germany
- Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607 Hamburg, Germany
- European Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
- Corresponding author.
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26
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Expression, purification and characterization of human proton-coupled oligopeptide transporter 1 hPEPT1. Protein Expr Purif 2021; 190:105990. [PMID: 34637915 DOI: 10.1016/j.pep.2021.105990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 09/27/2021] [Accepted: 10/05/2021] [Indexed: 11/22/2022]
Abstract
The human peptide transporter hPEPT1 (SLC15A1) is responsible for uptake of dietary di- and tripeptides and a number of drugs from the small intestine by utilizing the proton electrochemical gradient, and hence an important target for peptide-like drug design and drug delivery. hPEPT1 belongs to the ubiquitous major facilitator superfamily that all contain a 12TM core structure, with global conformational changes occurring during the transport cycle. Several bacterial homologues of these transporters have been characterized, providing valuable insight into the transport mechanism of this family. Here we report the overexpression and purification of recombinant hPEPT1 in a detergent-solubilized state. Thermostability profiling of hPEPT1 at different pH values revealed that hPEPT1 is more stable at pH 6 as compared to pH 7 and 8. Micro-scale thermophoresis (MST) confirmed that the purified hPEPT1 was able to bind di- and tripeptides respectively. To assess the in-solution oligomeric state of hPEPT1, negative stain electron microscopy was performed, demonstrating a predominantly monomeric state.
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27
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Immadisetty K, Moradi M. Mechanistic Picture for Chemomechanical Coupling in a Bacterial Proton-Coupled Oligopeptide Transporter from Streptococcus Thermophilus. J Phys Chem B 2021; 125:9738-9750. [PMID: 34424716 DOI: 10.1021/acs.jpcb.1c03982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Proton-coupled oligopeptide transporters (POTs) use the proton electrochemical gradient to transport peptides across the cell membrane. Despite the significant biological and biomedical relevance of these proteins, a detailed mechanistic picture for chemomechanical couplings involved in substrate/proton transport and protein structural changes is missing. Therefore, we performed microsecond-level molecular dynamics simulations of bacterial POT PepTSt, which shares ∼80% sequence identity with the human POT, PepT1, in the substrate-binding region. Three different conformational states of PepTSt were simulated, including (i) occluded, apo, (ii) inward-facing, apo, and (iii) inward-facingoccluded, Leu-Ala bound. We propose that the interaction of R33 with E299 and E300 acts as a conformational switch (i.e., to trigger the conformational change from an inward- to outward-facing state) in the substrate transport. Additionally, we propose that E299 and E400 disengage from interacting with the substrate either through protonation or through coordination with a cation for the substrate to get transported. This study provides clues to understand the chemomechanical couplings in POTs and paves the way to decipher the molecular-level underpinnings of the structure-function relationship in this important family of transporters.
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Affiliation(s)
| | - Mahmoud Moradi
- University of Arkansas, Fayetteville, Arkansas 72701, United States
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28
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Stauffer M, Ucurum Z, Harder D, Fotiadis D. Engineering and functional characterization of a proton-driven β-lactam antibiotic translocation module for bionanotechnological applications. Sci Rep 2021; 11:17205. [PMID: 34446740 PMCID: PMC8390754 DOI: 10.1038/s41598-021-96298-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 07/23/2021] [Indexed: 12/02/2022] Open
Abstract
Novel approaches in synthetic biology focus on the bottom-up modular assembly of natural, modified natural or artificial components into molecular systems with functionalities not found in nature. A possible application for such techniques is the bioremediation of natural water sources contaminated with small organic molecules (e.g., drugs and pesticides). A simple molecular system to actively accumulate and degrade pollutants could be a bionanoreactor composed of a liposome or polymersome scaffold combined with energizing- (e.g., light-driven proton pump), transporting- (e.g., proton-driven transporter) and degrading modules (e.g., enzyme). This work focuses on the engineering of a transport module specific for β-lactam antibiotics. We previously solved the crystal structure of a bacterial peptide transporter, which allowed us to improve the affinity for certain β-lactam antibiotics using structure-based mutagenesis combined with a bacterial uptake assay. We were able to identify specific mutations, which enhanced the affinity of the transporter for antibiotics containing certain structural features. Screening of potential compounds allowed for the identification of a β-lactam antibiotic ligand with relatively high affinity. Transport of antibiotics was evaluated using a solid-supported membrane electrophysiology assay. In summary, we have engineered a proton-driven β-lactam antibiotic translocation module, contributing to the growing toolset for bionanotechnological applications.
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Affiliation(s)
- Mirko Stauffer
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Zöhre Ucurum
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Daniel Harder
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Dimitrios Fotiadis
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland.
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29
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Parker JL, Deme JC, Wu Z, Kuteyi G, Huo J, Owens RJ, Biggin PC, Lea SM, Newstead S. Cryo-EM structure of PepT2 reveals structural basis for proton-coupled peptide and prodrug transport in mammals. SCIENCE ADVANCES 2021; 7:eabh3355. [PMID: 34433568 PMCID: PMC8386928 DOI: 10.1126/sciadv.abh3355] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/02/2021] [Indexed: 05/26/2023]
Abstract
The SLC15 family of proton-coupled solute carriers PepT1 and PepT2 play a central role in human physiology as the principal route for acquiring and retaining dietary nitrogen. A remarkable feature of the SLC15 family is their extreme substrate promiscuity, which has enabled the targeting of these transporters for the improvement of oral bioavailability for several prodrug molecules. Although recent structural and biochemical studies on bacterial homologs have identified conserved sites of proton and peptide binding, the mechanism of peptide capture and ligand promiscuity remains unclear for mammalian family members. Here, we present the cryo-electron microscopy structure of the outward open conformation of the rat peptide transporter PepT2 in complex with an inhibitory nanobody. Our structure, combined with molecular dynamics simulations and biochemical and cell-based assays, establishes a framework for understanding peptide and prodrug recognition within this pharmaceutically important transporter family.
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Affiliation(s)
- Joanne L Parker
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
| | - Justin C Deme
- Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
- Central Oxford Structural Molecular Imaging Centre, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Zhiyi Wu
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Gabriel Kuteyi
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Jiandong Huo
- Structural Biology, The Rosalind Franklin Institute, Harwell Science and Innovation Campus, Didcot, UK
- Division of Structural Biology, The Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
- Protein Production UK, The Research Complex at Harwell, Harwell Science and Innovation Campus, Didcot, UK
| | - Raymond J Owens
- Structural Biology, The Rosalind Franklin Institute, Harwell Science and Innovation Campus, Didcot, UK
- Division of Structural Biology, The Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
- Protein Production UK, The Research Complex at Harwell, Harwell Science and Innovation Campus, Didcot, UK
| | - Philip C Biggin
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
| | - Susan M Lea
- Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
- Central Oxford Structural Molecular Imaging Centre, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Simon Newstead
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
- The Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford OX1 3QU, UK
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30
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Kumar S, Athreya A, Gulati A, Nair RM, Mahendran I, Ranjan R, Penmatsa A. Structural basis of inhibition of a transporter from Staphylococcus aureus, NorC, through a single-domain camelid antibody. Commun Biol 2021; 4:836. [PMID: 34226658 PMCID: PMC8257674 DOI: 10.1038/s42003-021-02357-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 06/10/2021] [Indexed: 12/11/2022] Open
Abstract
Transporters play vital roles in acquiring antimicrobial resistance among pathogenic bacteria. In this study, we report the X-ray structure of NorC, a 14-transmembrane major facilitator superfamily member that is implicated in fluoroquinolone resistance in drug-resistant Staphylococcus aureus strains, at a resolution of 3.6 Å. The NorC structure was determined in complex with a single-domain camelid antibody that interacts at the extracellular face of the transporter and stabilizes it in an outward-open conformation. The complementarity determining regions of the antibody enter and block solvent access to the interior of the vestibule, thereby inhibiting alternating-access. NorC specifically interacts with an organic cation, tetraphenylphosphonium, although it does not demonstrate an ability to transport it. The interaction is compromised in the presence of NorC-antibody complex, consequently establishing a strategy to detect and block NorC and related transporters through the use of single-domain camelid antibodies.
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Affiliation(s)
- Sushant Kumar
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
- Van Andel Institute, Grand Rapids, MI, USA
| | - Arunabh Athreya
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Ashutosh Gulati
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Rahul Mony Nair
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Ithayaraja Mahendran
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
- Structural Parasitology Lab, International Centre for Genetic engineering and Biotechnology, New Delhi, India
| | - Rakesh Ranjan
- Principal Scientist, ICAR-National Research Centre of Camel (NRCC), Bikaner, India
| | - Aravind Penmatsa
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.
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31
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Drew D, North RA, Nagarathinam K, Tanabe M. Structures and General Transport Mechanisms by the Major Facilitator Superfamily (MFS). Chem Rev 2021; 121:5289-5335. [PMID: 33886296 PMCID: PMC8154325 DOI: 10.1021/acs.chemrev.0c00983] [Citation(s) in RCA: 153] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Indexed: 12/12/2022]
Abstract
The major facilitator superfamily (MFS) is the largest known superfamily of secondary active transporters. MFS transporters are responsible for transporting a broad spectrum of substrates, either down their concentration gradient or uphill using the energy stored in the electrochemical gradients. Over the last 10 years, more than a hundred different MFS transporter structures covering close to 40 members have provided an atomic framework for piecing together the molecular basis of their transport cycles. Here, we summarize the remarkable promiscuity of MFS members in terms of substrate recognition and proton coupling as well as the intricate gating mechanisms undergone in achieving substrate translocation. We outline studies that show how residues far from the substrate binding site can be just as important for fine-tuning substrate recognition and specificity as those residues directly coordinating the substrate, and how a number of MFS transporters have evolved to form unique complexes with chaperone and signaling functions. Through a deeper mechanistic description of glucose (GLUT) transporters and multidrug resistance (MDR) antiporters, we outline novel refinements to the rocker-switch alternating-access model, such as a latch mechanism for proton-coupled monosaccharide transport. We emphasize that a full understanding of transport requires an elucidation of MFS transporter dynamics, energy landscapes, and the determination of how rate transitions are modulated by lipids.
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Affiliation(s)
- David Drew
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Rachel A. North
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Kumar Nagarathinam
- Center
of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Lübeck, D-23538, Lübeck, Germany
| | - Mikio Tanabe
- Structural
Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Oho 1-1, Tsukuba, Ibaraki 305-0801, Japan
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32
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Recent advances in understanding prodrug transport through the SLC15 family of proton-coupled transporters. Biochem Soc Trans 2021; 48:337-346. [PMID: 32219385 PMCID: PMC7200629 DOI: 10.1042/bst20180302] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/15/2020] [Accepted: 03/04/2020] [Indexed: 12/28/2022]
Abstract
Solute carrier (SLC) transporters play important roles in regulating the movement of small molecules and ions across cellular membranes. In mammals, they play an important role in regulating the uptake of nutrients and vitamins from the diet, and in controlling the distribution of their metabolic intermediates within the cell. Several SLC families also play an important role in drug transport and strategies are being developed to hijack SLC transporters to control and regulate drug transport within the body. Through the addition of amino acid and peptide moieties several novel antiviral and anticancer agents have been developed that hijack the proton-coupled oligopeptide transporters, PepT1 (SCL15A1) and PepT2 (SLC15A2), for improved intestinal absorption and renal retention in the body. A major goal is to understand the rationale behind these successes and expand the library of prodrug molecules that utilise SLC transporters. Recent co-crystal structures of prokaryotic homologues of the human PepT1 and PepT2 transporters have shed important new insights into the mechanism of prodrug recognition. Here, I will review recent developments in our understanding of ligand recognition and binding promiscuity within the SLC15 family, and discuss current models for prodrug recognition.
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33
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Abstract
Drug transporters are integral membrane proteins that play a critical role in drug disposition by affecting absorption, distribution, and excretion. They translocate drugs, as well as endogenous molecules and toxins, across membranes using ATP hydrolysis, or ion/concentration gradients. In general, drug transporters are expressed ubiquitously, but they function in drug disposition by being concentrated in tissues such as the intestine, the kidneys, the liver, and the brain. Based on their primary sequence and their mechanism, transporters can be divided into the ATP-binding cassette (ABC), solute-linked carrier (SLC), and the solute carrier organic anion (SLCO) superfamilies. Many X-ray crystallography and cryo-electron microscopy (cryo-EM) structures have been solved in the ABC and SLC transporter superfamilies or of their bacterial homologs. The structures have provided valuable insight into the structural basis of transport. This chapter will provide particular focus on the promiscuous drug transporters because of their effect on drug disposition and the challenges associated with them.
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Affiliation(s)
- Arthur G Roberts
- Pharmaceutical and Biomedical Sciences Department, University of Georgia, Athens, GA, USA.
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34
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Prabhala BK, Rahman M, Nour-Eldin HH, Jørgensen FS, Mirza O. PTR2/POT/NPF transporters: what makes them tick? ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020; 123:219-240. [PMID: 33485485 DOI: 10.1016/bs.apcsb.2020.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PTR2/POT/NPF are a family of primarily proton coupled transporters that belong to the major facilitator super family and are found across most kingdoms of life. They are involved in uptake of nutrients, hormones, ions and several orally administered drug molecules. A wealth of structural and functional data is available for this family; the similarity between the protein structural features have been discussed and investigated in detail on several occasions, however there are no reports on the unification of substrate information. In order to fill this gap, we have collected information about substrates across the entire PTR2/POT/NPF family in order to provide key insights into what makes a molecule a substrate and whether there are common features among confirmed substrates. This review will be of particular interest for researchers in the field trying to probe the mechanisms responsible for the different selectivity of these transporters at a molecular resolution, and to design novel substrates.
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Affiliation(s)
- Bala K Prabhala
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - Moazur Rahman
- School of Biological Sciences, University of the Punjab, Lahore, Punjab, Pakistan; Drug Discovery and Structural Biology Group, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Punjab, Pakistan
| | - Hussam H Nour-Eldin
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Flemming Steen Jørgensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Osman Mirza
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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35
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Lasitza‐Male T, Bartels K, Jungwirth J, Wiggers F, Rosenblum G, Hofmann H, Löw C. Membrane Chemistry Tunes the Structure of a Peptide Transporter. Angew Chem Int Ed Engl 2020; 59:19121-19128. [PMID: 32744783 PMCID: PMC7590137 DOI: 10.1002/anie.202008226] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Indexed: 01/02/2023]
Abstract
Membrane proteins require lipid bilayers for function. While lipid compositions reach enormous complexities, high-resolution structures are usually obtained in artificial detergents. To understand whether and how lipids guide membrane protein function, we use single-molecule FRET to probe the dynamics of DtpA, a member of the proton-coupled oligopeptide transporter (POT) family, in various lipid environments. We show that detergents trap DtpA in a dynamic ensemble with cytoplasmic opening. Only reconstitutions in more native environments restore cooperativity, allowing an opening to the extracellular side and a sampling of all relevant states. Bilayer compositions tune the abundance of these states. A novel state with an extreme cytoplasmic opening is accessible in bilayers with anionic head groups. Hence, chemical diversity of membranes translates into structural diversity, with the current POT structures only sampling a portion of the full structural space.
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Affiliation(s)
- Tanya Lasitza‐Male
- Department of Structural BiologyWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Kim Bartels
- Centre for Structural Systems Biology (CSSB)DESY and European Molecular Biology Laboratory HamburgNotkestrasse 8522607HamburgGermany
| | - Jakub Jungwirth
- Department of Chemical and Biological PhysicsWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Felix Wiggers
- Department of Structural BiologyWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Gabriel Rosenblum
- Department of Structural BiologyWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Hagen Hofmann
- Department of Structural BiologyWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB)DESY and European Molecular Biology Laboratory HamburgNotkestrasse 8522607HamburgGermany
- Department of Medical Biochemistry and BiophysicsKarolinska Institutet17177StockholmSweden
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36
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Lasitza‐Male T, Bartels K, Jungwirth J, Wiggers F, Rosenblum G, Hofmann H, Löw C. Membrane Chemistry Tunes the Structure of a Peptide Transporter. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Tanya Lasitza‐Male
- Department of Structural Biology Weizmann Institute of Science Herzl St. 234 7610001 Rehovot Israel
| | - Kim Bartels
- Centre for Structural Systems Biology (CSSB) DESY and European Molecular Biology Laboratory Hamburg Notkestrasse 85 22607 Hamburg Germany
| | - Jakub Jungwirth
- Department of Chemical and Biological Physics Weizmann Institute of Science Herzl St. 234 7610001 Rehovot Israel
| | - Felix Wiggers
- Department of Structural Biology Weizmann Institute of Science Herzl St. 234 7610001 Rehovot Israel
| | - Gabriel Rosenblum
- Department of Structural Biology Weizmann Institute of Science Herzl St. 234 7610001 Rehovot Israel
| | - Hagen Hofmann
- Department of Structural Biology Weizmann Institute of Science Herzl St. 234 7610001 Rehovot Israel
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB) DESY and European Molecular Biology Laboratory Hamburg Notkestrasse 85 22607 Hamburg Germany
- Department of Medical Biochemistry and Biophysics Karolinska Institutet 17177 Stockholm Sweden
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37
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Johnson EO, Office E, Kawate T, Orzechowski M, Hung DT. Large-Scale Chemical-Genetic Strategy Enables the Design of Antimicrobial Combination Chemotherapy in Mycobacteria. ACS Infect Dis 2020; 6:56-63. [PMID: 31721551 PMCID: PMC6958538 DOI: 10.1021/acsinfecdis.9b00373] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The efficacies of all antibiotics against tuberculosis are eventually eroded by resistance. New strategies to discover drugs or drug combinations with higher barriers to resistance are needed. Previously, we reported the application of a large-scale chemical-genetic interaction screening strategy called PROSPECT (PRimary screening Of Strains to Prioritize Expanded Chemistry and Targets) for the discovery of new Mycobacterium tuberculosis inhibitors, which resulted in the identification of the small molecule BRD-8000, an inhibitor of a novel target, EfpA [ Johnson et al. ( 2019 ) Nature 517 , 72 ]. Leveraging the chemical genetic interaction profile of BRD-8000, we identified BRD-9327, another structurally distinct small molecule EfpA inhibitor. We show that the two compounds are synergistic and display collateral sensitivity because of their distinct modes of action and resistance mechanisms. High-level resistance to one increases the sensitivity to and reduces the emergence of resistance to the other. Thus, the combination of BRD-9327 and BRD-8000 represents a proof-of-concept for the novel strategy of leveraging chemical genetics in the design of antimicrobial combination chemotherapy in which mutual collateral sensitivity is exploited.
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Affiliation(s)
- Eachan O. Johnson
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Emma Office
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Tomohiko Kawate
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Marek Orzechowski
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Deborah T. Hung
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
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Li Y, Di C, Wu J, Si J, Zhang Q, Zhang H, Ge Y, Liu D, Liu W. Selective imaging of analytes in living cells and zebrafish using a novel peptide-based fluorescence chemosensor with different responses. Microchem J 2019. [DOI: 10.1016/j.microc.2019.104182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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High-throughput stability screening for detergent-solubilized membrane proteins. Sci Rep 2019; 9:10379. [PMID: 31316088 PMCID: PMC6637136 DOI: 10.1038/s41598-019-46686-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 07/03/2019] [Indexed: 01/08/2023] Open
Abstract
Protein stability in detergent or membrane-like environments is the bottleneck for structural studies on integral membrane proteins (IMP). Irrespective of the method to study the structure of an IMP, detergent solubilization from the membrane is usually the first step in the workflow. Here, we establish a simple, high-throughput screening method to identify optimal detergent conditions for membrane protein stabilization. We apply differential scanning fluorimetry in combination with scattering upon thermal denaturation to study the unfolding of integral membrane proteins. Nine different prokaryotic and eukaryotic membrane proteins were used as test cases to benchmark our detergent screening method. Our results show that it is possible to measure the stability and solubility of IMPs by diluting them from their initial solubilization condition into different detergents. We were able to identify groups of detergents with characteristic stabilization and destabilization effects for selected targets. We further show that fos-choline and PEG family detergents may lead to membrane protein destabilization and unfolding. Finally, we determined thenmodynamic parameters that are important indicators of IMP stability. The described protocol allows the identification of conditions that are suitable for downstream handling of membrane proteins during purification.
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