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Hilpert K, Munshi T, López-Pérez PM, Sequeira-Garcia J, Bull TJ. Redefining Peptide 14D: Substitutional Analysis for Accelerated TB Diagnosis and Enhanced Activity against Mycobacterium tuberculosis. Microorganisms 2024; 12:177. [PMID: 38258003 PMCID: PMC10819809 DOI: 10.3390/microorganisms12010177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/08/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024] Open
Abstract
Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a predominant cause of mortality, especially in low- and middle-income nations. Recently, antimicrobial peptides have been discovered that at low concentrations could stimulate the growth of M. tuberculosis (hormetic response). In this study, such a peptide was used to investigate the effects on the time to positivity (TTP). A systematic substitution analysis of peptide 14D was synthesized using Spot synthesis technology, resulting in 171 novel peptides. Our findings revealed a spectrum of interactions, with some peptides accelerating M. tuberculosis growth, potentially aiding in faster diagnostics, while others exhibited inhibitory effects. Notably, peptide NH2-wkivfiwrr-CONH2 significantly reduced the TTP by 25 h compared to the wild-type peptide 14D, highlighting its potential in improving TB diagnostics by culture. Several peptides demonstrated potent antimycobacterial activity, with a minimum inhibitory concentration (MIC) of 20 µg/mL against H37Rv and a multidrug-resistant M. tuberculosis strain. Additionally, for two peptides, a strongly diminished formation of cord-like structures was observed, which is indicative of reduced virulence and transmission potential. This study underscores the multifaceted roles of antimicrobial peptides in TB management, from enhancing diagnostic efficiency to offering therapeutic avenues against M. tuberculosis.
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Affiliation(s)
- Kai Hilpert
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Tulika Munshi
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
| | | | | | - Tim J. Bull
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
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Lubich C, Steinitz KN, Hoelbl B, Prenninger T, van Helden PM, Weiller M, Reipert BM. Modulating the microenvironment during FVIII uptake influences the nature of FVIII-peptides presented by antigen-presenting cells. Front Immunol 2022; 13:975680. [DOI: 10.3389/fimmu.2022.975680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
Background and aimsHemophilia A is a severe bleeding disorder caused by the deficiency of functionally active coagulation factor VIII (FVIII). The induction of neutralizing anti-drug antibodies is a major complication in the treatment of hemophilia A patients with FVIII replacement therapies. Why some patients develop neutralizing antibodies (FVIII inhibitors) while others do not is not well understood. Previous studies indicated that the induction of FVIII inhibitors requires cognate interactions between FVIII-specific B cells and FVIII-specific CD4+ T cells in germinal center reactions. In this study, we investigated the FVIII peptide repertoire presented by antigen-presenting cells (APCs) under different microenvironment conditions that are expected to alter the uptake of FVIII by APCs. The aim of this study was to better understand the association between different microenvironment conditions during FVIII uptake and the FVIII peptide patterns presented by APCs.MethodsWe used a FVIII-specific CD4+ T cell hybridoma library derived from humanized HLA-DRB1*1501 (human MHC class II) hemophilic mice that were treated with human FVIII. APCs obtained from the same mouse strain were preincubated with FVIII under different conditions which are expected to alter the uptake of FVIII by APCs. Subsequently, these preincubated APCs were used to stimulate the FVIII-specific CD4+ T cell hybridoma library. Stimulation of peptide-specific CD4+ T-cell hybridoma clones was assessed by analyzing the IL-2 release into cell culture supernatants.ResultsThe results of this study indicate that the specific microenvironment conditions during FVIII uptake by APCs determine the peptide specificities of subsequently activated FVIII-specific CD4+ T cell hybridoma clones. Incubation of APCs with FVIII complexed with von Willebrand Factor, FVIII activated by thrombin or FVIII combined with a blockade of receptors on APCs previously associated with FVIII uptake and clearance, resulted in distinct peptide repertoires of subsequently activated hybridoma clones.ConclusionBased on our data we conclude that the specific microenvironment during FVIII uptake by APCs determines the FVIII peptide repertoire presented on MHC class II expressed by APCs and the peptide specificity of subsequently activated FVIII-specific CD4+ T cell hybridoma clones.
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Sereikaite V, Fritzius T, Kasaragod VB, Bader N, Maric HM, Schindelin H, Bettler B, Strømgaard K. Targeting the γ-Aminobutyric Acid Type B (GABA B) Receptor Complex: Development of Inhibitors Targeting the K + Channel Tetramerization Domain (KCTD) Containing Proteins/GABA B Receptor Protein-Protein Interaction. J Med Chem 2019; 62:8819-8830. [PMID: 31509708 DOI: 10.1021/acs.jmedchem.9b01087] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Targeting multiprotein receptor complexes, rather than receptors directly, is a promising concept in drug discovery. This is particularly relevant to the GABAB receptor complex, which plays a prominent role in many brain functions and diseases. Here, we provide the first studies targeting a key protein-protein interaction of the GABAB receptor complex-the interaction with KCTD proteins. By employing the μSPOT technology, we first defined the GABAB receptor-binding epitope mediating the KCTD interaction. Subsequently, we developed a highly potent peptide-based inhibitor that interferes with the KCTD/GABAB receptor complex and efficiently isolates endogenous KCTD proteins from mouse brain lysates. X-ray crystallography and SEC-MALS revealed inhibitor induced oligomerization of KCTD16 into a distinct hexameric structure. Thus, we provide a template for modulating the GABAB receptor complex, revealing a fundamentally novel approach for targeting GABAB receptor-associated neuropsychiatric disorders.
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Affiliation(s)
- Vita Sereikaite
- Center for Biopharmaceuticals, Department of Drug Design and Pharmacology , University of Copenhagen , 2100 Copenhagen , Denmark
| | - Thorsten Fritzius
- Department of Biomedicine , University of Basel , CH-4056 Basel , Switzerland
| | - Vikram B Kasaragod
- Rudolf Virchow Center for Experimental Biomedicine , University of Würzburg , 97080 Würzburg , Germany
| | - Nicole Bader
- Rudolf Virchow Center for Experimental Biomedicine , University of Würzburg , 97080 Würzburg , Germany
| | - Hans M Maric
- Center for Biopharmaceuticals, Department of Drug Design and Pharmacology , University of Copenhagen , 2100 Copenhagen , Denmark
| | - Hermann Schindelin
- Rudolf Virchow Center for Experimental Biomedicine , University of Würzburg , 97080 Würzburg , Germany
| | - Bernhard Bettler
- Department of Biomedicine , University of Basel , CH-4056 Basel , Switzerland
| | - Kristian Strømgaard
- Center for Biopharmaceuticals, Department of Drug Design and Pharmacology , University of Copenhagen , 2100 Copenhagen , Denmark
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López-Pérez PM, Grimsey E, Bourne L, Mikut R, Hilpert K. Screening and Optimizing Antimicrobial Peptides by Using SPOT-Synthesis. Front Chem 2017; 5:25. [PMID: 28447030 PMCID: PMC5388751 DOI: 10.3389/fchem.2017.00025] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/29/2017] [Indexed: 11/14/2022] Open
Abstract
Peptide arrays on cellulose are a powerful tool to investigate peptide interactions with a number of different molecules, for examples antibodies, receptors or enzymes. Such peptide arrays can also be used to study interactions with whole cells. In this review, we focus on the interaction of small antimicrobial peptides with bacteria. Antimicrobial peptides (AMPs) can kill multidrug-resistant (MDR) human pathogenic bacteria and therefore could be next generation antibiotics targeting MDR bacteria. We describe the screen and the result of different optimization strategies of peptides cleaved from the membrane. In addition, screening of antibacterial activity of peptides that are tethered to the surface is discussed. Surface-active peptides can be used to protect surfaces from bacterial infections, for example implants.
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Affiliation(s)
| | - Elizabeth Grimsey
- Institute for Infection and Immunity, St. George's University of LondonLondon, UK
| | - Luc Bourne
- Institute for Infection and Immunity, St. George's University of LondonLondon, UK
| | - Ralf Mikut
- Karlsruhe Institute of Technology (KIT), Institute for Applied Computer Science (IAI)Eggenstein-Leopoldshafen, Germany
| | - Kai Hilpert
- TiKa Diagnostics LtdLondon, UK
- Institute for Infection and Immunity, St. George's University of LondonLondon, UK
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5
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SPOTing Acetyl-Lysine Dependent Interactions. MICROARRAYS 2015; 4:370-88. [PMID: 27600229 PMCID: PMC4996381 DOI: 10.3390/microarrays4030370] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/04/2015] [Accepted: 08/11/2015] [Indexed: 12/05/2022]
Abstract
Post translational modifications have been recognized as chemical signals that create docking sites for evolutionary conserved effector modules, allowing for signal integration within large networks of interactions. Lysine acetylation in particular has attracted attention as a regulatory modification, affecting chromatin structure and linking to transcriptional activation. Advances in peptide array technologies have facilitated the study of acetyl-lysine-containing linear motifs interacting with the evolutionary conserved bromodomain module, which specifically recognizes and binds to acetylated sequences in histones and other proteins. Here we summarize recent work employing SPOT peptide technology to identify acetyl-lysine dependent interactions and document the protocols adapted in our lab, as well as our efforts to characterize such bromodomain-histone interactions. Our results highlight the versatility of SPOT methods and establish an affordable tool for rapid access to potential protein/modified-peptide interactions involving lysine acetylation.
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Schirwitz C, Loeffler FF, Felgenhauer T, Stadler V, Nesterov-Mueller A, Dahint R, Breitling F, Bischoff FR. Purification of high-complexity peptide microarrays by spatially resolved array transfer to gold-coated membranes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:1598-1602. [PMID: 23315653 DOI: 10.1002/adma.201203853] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 11/22/2012] [Indexed: 06/01/2023]
Abstract
A method for the one-step purification of high-complexity peptide microarrays is presented. The entire peptide library is transferred from the synthesis support to a gold coated polyvinylidenfluoride (PVDF) membrane, whereby only full-length peptides covalently couple to the receptor membrane via an N-terminally added cysteine. Highly resolved peptide transfer and purification of up to 10 000 features per cm(2) is demonstrated.
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Affiliation(s)
- Christopher Schirwitz
- German Cancer Research Center (DKFZ), Functional Genome Analysis, Chip-based Peptide Libraries, Heidelberg, Germany.
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Jaeger IS, Kretzschmar I, Körner J, Weiser AA, Mahrenholz CC, Potty A, Kourentzi K, Willson RC, Volkmer R, Preissner R. Mapping discontinuous protein-binding sites via structure-based peptide libraries: combiningin silicoandin vitroapproaches. J Mol Recognit 2012; 26:23-31. [DOI: 10.1002/jmr.2237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 08/23/2012] [Accepted: 08/24/2012] [Indexed: 11/09/2022]
Affiliation(s)
- Ines S. Jaeger
- Institute for Physiology, Structural Bioinformatics Group; Charité-Universitätsmedizin Berlin; Lindenberger Weg 80; 13125; Berlin; Germany
| | - Ines Kretzschmar
- Institut für Medizinische Immunologie, Molecular Libraries and Recognition Group; Charité-Universitätsmedizin Berlin; Hessische Strasse 3-4; 10115; Berlin; Germany
| | - Jana Körner
- Leibniz-Institut für Molekulare Pharmakologie im Forschungsverbund Berlin e.V. (FMP); R.-Rössle-Strasse 10; 13125; Berlin; Germany
| | | | - Carsten C. Mahrenholz
- Institut für Medizinische Immunologie, Molecular Libraries and Recognition Group; Charité-Universitätsmedizin Berlin; Hessische Strasse 3-4; 10115; Berlin; Germany
| | | | - Katerina Kourentzi
- University of Houston; Department of Chemical and Biomolecular Engineering; Houston; TX; 77204-4004; USA
| | - Richard C. Willson
- University of Houston; Department of Chemical and Biomolecular Engineering; Houston; TX; 77204-4004; USA
| | - Rudolf Volkmer
- Institut für Medizinische Immunologie, Molecular Libraries and Recognition Group; Charité-Universitätsmedizin Berlin; Hessische Strasse 3-4; 10115; Berlin; Germany
| | - Robert Preissner
- Institute for Physiology, Structural Bioinformatics Group; Charité-Universitätsmedizin Berlin; Lindenberger Weg 80; 13125; Berlin; Germany
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Steinitz KN, van Helden PM, Binder B, Wraith DC, Unterthurner S, Hermann C, Schuster M, Ahmad RU, Weiller M, Lubich C, de la Rosa M, Schwarz HP, Reipert BM. CD4+ T-cell epitopes associated with antibody responses after intravenously and subcutaneously applied human FVIII in humanized hemophilic E17 HLA-DRB1*1501 mice. Blood 2012; 119:4073-82. [PMID: 22394599 PMCID: PMC3986681 DOI: 10.1182/blood-2011-08-374645] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Today it is generally accepted that B cells require cognate interactions with CD4(+) T cells to develop high-affinity antibodies against proteins. CD4(+) T cells recognize peptides (epitopes) presented by MHC class II molecules that are expressed on antigen-presenting cells. Structural features of both the MHC class II molecule and the peptide determine the specificity of CD4(+) T cells that can bind to the MHC class II-peptide complex. We used a new humanized hemophilic mouse model to identify FVIII peptides presented by HLA-DRB1*1501. This model carries a knockout of all murine MHC class II molecules and expresses a chimeric murine-human MHC class II complex that contains the peptide-binding sites of the human HLA-DRB1*1501. When mice were treated with human FVIII, the proportion of mice that developed antibodies depended on the application route of FVIII and the activation state of the innate immune system. We identified 8 FVIII peptide regions that contained CD4(+) T-cell epitopes presented by HLA-DRB1*1501 to CD4(+) T cells during immune responses against FVIII. CD4(+) T-cell responses after intravenous and subcutaneous application of FVIII involved the same immunodominant FVIII epitopes. Interestingly, most of the 8 peptide regions contained promiscuous epitopes that bound to several different HLA-DR proteins in in vitro binding assays.
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Volkmer R, Tapia V, Landgraf C. Synthetic peptide arrays for investigating protein interaction domains. FEBS Lett 2012; 586:2780-6. [PMID: 22576123 DOI: 10.1016/j.febslet.2012.04.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 04/16/2012] [Accepted: 04/17/2012] [Indexed: 11/28/2022]
Abstract
Synthetic peptide array technology was first developed in the early 1990s by Ronald Frank. Since then the technique has become a powerful tool for high throughput approaches in biology and biochemistry. Here, we focus on peptide arrays applied to investigate the binding specificity of protein interaction domains such as WW, SH3, and PDZ domains. We describe array-based methods used to reveal domain networks in yeast, and briefly review rules as well as ideas about the synthesis and application of peptide arrays. We also provide initial results of a study designed to investigate the nature and evolution of SH3 domain interaction networks in eukaryotes.
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Affiliation(s)
- Rudolf Volkmer
- Institut für Medizinische Immunologie Berlin, Molecular Libraries and Recognition Group, Charité-Universitätsmedizin Berlin, Hessische Str. 3-4, 10115 Berlin, Germany.
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Volkmer R, Kretzschmar I, Tapia V. Mapping receptor–ligand interactions with synthetic peptide arrays: Exploring the structure and function of membrane receptors. Eur J Cell Biol 2012; 91:349-56. [DOI: 10.1016/j.ejcb.2011.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Revised: 03/15/2011] [Accepted: 03/17/2011] [Indexed: 11/25/2022] Open
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Katz C, Levy-Beladev L, Rotem-Bamberger S, Rito T, Rüdiger SGD, Friedler A. Studying protein–protein interactions using peptide arrays. Chem Soc Rev 2011; 40:2131-45. [DOI: 10.1039/c0cs00029a] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Ruppel E, Aÿ B, Boisguerin P, Dölle S, Worm M, Volkmer R. Identification of IgE Binding to Api g 1-Derived Peptides. Chembiochem 2010; 11:2283-93. [DOI: 10.1002/cbic.201000322] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
Development of array technologies started in the late 1980s and was first extensively applied to DNA arrays especially in the genomic field. Today this technique has become a powerful tool for high-throughput approaches in biology and chemistry. Progresses were mainly driven by the human genome project and were associated with the development of several new technologies, which led to the onset of additional "omic" topics like proteomics, glycomics, antibodyomics or lipidomics. The main characteristics of the array technology are (i) spatially addressable immobilization of a huge number of different capture molecules; (ii) probing the array in a simultaneous and highly parallel manner with a biological sample; (iii) tendency towards miniaturization of the arrays; and (iv) software-supported read-out and data analysis. We review some general concepts about peptide arrays on planar supports and point out technical aspects concerning the generation of peptide microarrays. Finally, we discuss recent applications by describing relevant literature.
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Volkmer R. Synthesis and application of peptide arrays: quo vadis SPOT technology. Chembiochem 2009; 10:1431-42. [PMID: 19437530 DOI: 10.1002/cbic.200900078] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Rudolf Volkmer
- Institut für Medizinische Immunologie, AG Molekulare Bibliotheken, Charité-Universitätsmedizin Berlin, Hessische Strasse 3-4, 10115 Berlin, Germany.
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Ay B, Landgraf K, Streitz M, Fuhrmann S, Volkmer R, Boisguerin P. Using hydroxymethylphenoxy derivates with the SPOT technology to generate peptides with authentic C-termini. Bioorg Med Chem Lett 2008; 18:4038-43. [PMID: 18565750 DOI: 10.1016/j.bmcl.2008.05.116] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2008] [Revised: 05/29/2008] [Accepted: 05/31/2008] [Indexed: 10/22/2022]
Abstract
The SPOT technology can fulfill most requirements for highly parallel, multiple peptide synthesis of soluble peptides within the upper microgram range. Here, we report on an improved method using hydroxymethylphenoxyacetic acid (HMPA) for 19 amino acids and 4-(4-hydroxymethyl-3-methoxyphenoxy)-butyric acid (HMPB) for proline as acidic labile linkers in SPOT synthesis. Using this approach we could reduce side-chain reactions normally occurring during conventional alkaline peptide cleavage from cellulose membranes. All synthesis steps were adapted to fully-automated SPOT synthesis and therefore represent a time- and cost-saving procedure. Furthermore, the improved cleavage and washing steps resulted in peptides with authentic C-termini in a purity range of 60-95%. Our improved method is ideal for synthesizing many thousand different peptides subsequently used directly for different biological assays requiring authentic C-termini, such as CD8 T-cell epitope screening, vaccine immunization, or tumor imaging.
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Affiliation(s)
- Bernhard Ay
- Institut für Medizinische Immunologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
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Blüschke B, Eckey V, Kunert B, Berendt S, Landmesser H, Portwich M, Volkmer R, Schneider E. Mapping Putative Contact Sites Between Subunits in a Bacterial ATP-binding Cassette (ABC) Transporter by Synthetic Peptide Libraries. J Mol Biol 2007; 369:386-99. [PMID: 17434534 DOI: 10.1016/j.jmb.2007.03.043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 03/12/2007] [Accepted: 03/13/2007] [Indexed: 01/09/2023]
Abstract
The maltose ATP-binding cassette transporter of Salmonella typhimurium is composed of the soluble periplasmic receptor, MalE, and a membrane-associated complex comprising one copy each of the pore-forming hydrophobic subunits, MalF and MalG, and of a homodimer of the ATP-hydrolyzing subunit, MalK. During the transport process the subunits are thought to undergo conformational changes that might transiently alter molecular contacts between MalFG and MalK(2). In order to map sites of subunit-subunit interactions we have used a comprehensive peptide mapping approach comprising large-scale microsynthesis of labelled probes and array techniques. In particular, we screened the binding of (i) MalFG-derived soluble biotinylated peptides to immobilized MalK, and (ii) radiolabelled MalK to MalFG-derived cellulose membrane-bound peptides. The first approach identified seven peptides (10mers) each of MalF and MalG that specifically bound to MalK. The peptides were localized to TMDs 3 and 6, periplasmic loop P4 and cytoplasmic loops C2 and C3 of MalF, while MalG-derived peptides localized to the N terminus, TMDs 4-6, periplasmic loop P1 and cytoplasmic loop C2. Peptides from C3 and C2, respectively, of MalF and MalG partially encompass the conserved EAA-motif, known to be crucial for interaction with MalK. These results were basically confirmed by screening MalFG-derived peptide arrays consisting of 16mers or 31mers with radiolabelled MalK. This approach also allowed us to perform complete substitutional analyses of peptides in question. The results led to the construction of MalFG variants that were subsequently analyzed for functional consequences in vivo. Growth experiments revealed that most of the mutations had no phenotype, suggesting that the mutated residues themselves are not critical but part of a discontinuous binding site. However, two novel mutations affecting residues from the EAA motifs of MalF (Ile417Glu) and MalG (Phe203Gln/Asn), respectively, displayed severe growth defects, indicating their functional importance. Together, these experimental outcomes identify specific molecular contacts made between MalK and MalFG that extend beyond the well-characterized EAA motif.
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Affiliation(s)
- Bettina Blüschke
- Humboldt Universität zu Berlin, Institut für Biologie/Bakterienphysiologie, Chausseestr. 117, D-10115 Berlin, Germany
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