1
|
Chaleshtori ZA, Rastegari AA, Nayeri H, Doosti A. Use of immunoinformatics and the simulation approach to identify Helicobacter pylori epitopes to design a multi-epitope subunit vaccine for B- and T-cells. BMC Biotechnol 2023; 23:42. [PMID: 37759228 PMCID: PMC10537100 DOI: 10.1186/s12896-023-00814-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND Helicobacter pylori cause a variety of gastric malignancies, gastric ulcers, and cause erosive diseases. The extreme nature of the bacterium and the implantation of this bacterium protects it against designing a potent drug against it. Therefore, employing a precise and effective design for a more safe and stable antigenic vaccine against this pathogen can effectively control its associated infections. This study, aimed at improving the design of multiple subunit vaccines against H. pylori, adopts multiple immunoinformatics approaches in combination with other computational approaches. RESULTS In this regard, 10 HTL, and 11 CTL epitopes were employed based on appropriate adopted MHC binding scores and c-terminal cut-off scores of 4 main selected proteins (APO, LeoA, IceA1, and IceA2). An adjuvant was added to the N end of the vaccine to achieve higher stability. For validation, immunogenicity and sensitization of physicochemical analyses were performed. The vaccine could be antigenic with significantly strong interactions with TOLK-2, 4, 5, and 9 receptors. The designed vaccine was subjected to Gromacs simulation and immune response prediction modelling that confirmed expression and immune-stimulating response efficiency. Besides, the designed vaccine showed better interactions with TLK-9. CONCLUSIONS Based on our analyses, although the suggested vaccine could induce a clear response against H. pylori, precise laboratory validation is required to confirm its immunogenicity and safety status.
Collapse
Affiliation(s)
| | - Ali Asghar Rastegari
- Department of Molecular and Cell Biochemistry, Falavarjan Branch, Islamic Azad University, Isfahan, Iran.
| | - Hashem Nayeri
- Department of Biochemistry, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
| | - Abbas Doosti
- Biotechnology Research Center, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| |
Collapse
|
2
|
Smithers L, Degtjarik O, Weichert D, Huang CY, Boland C, Bowen K, Oluwole A, Lutomski C, Robinson CV, Scanlan EM, Wang M, Olieric V, Shalev-Benami M, Caffrey M. Structure snapshots reveal the mechanism of a bacterial membrane lipoprotein N-acyltransferase. SCIENCE ADVANCES 2023; 9:eadf5799. [PMID: 37390210 PMCID: PMC10313180 DOI: 10.1126/sciadv.adf5799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 05/26/2023] [Indexed: 07/02/2023]
Abstract
Bacterial lipoproteins (BLPs) decorate the surface of membranes in the cell envelope. They function in membrane assembly and stability, as enzymes, and in transport. The final enzyme in the BLP synthesis pathway is the apolipoprotein N-acyltransferase, Lnt, which is proposed to act by a ping-pong mechanism. Here, we use x-ray crystallography and cryo-electron microscopy to chart the structural changes undergone during the progress of the enzyme through the reaction. We identify a single active site that has evolved to bind, individually and sequentially, substrates that satisfy structural and chemical criteria to position reactive parts next to the catalytic triad for reaction. This study validates the ping-pong mechanism, explains the molecular bases for Lnt's substrate promiscuity, and should facilitate the design of antibiotics with minimal off-target effects.
Collapse
Affiliation(s)
- Luke Smithers
- School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin D02 R590, Ireland
| | - Oksana Degtjarik
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Dietmar Weichert
- School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin D02 R590, Ireland
| | - Chia-Ying Huang
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Coilín Boland
- School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin D02 R590, Ireland
| | - Katherine Bowen
- School of Chemistry, Trinity College Dublin, Dublin D02 R590, Ireland
| | - Abraham Oluwole
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Corinne Lutomski
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Carol V. Robinson
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Eoin M. Scanlan
- School of Chemistry, Trinity College Dublin, Dublin D02 R590, Ireland
| | - Meitian Wang
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Vincent Olieric
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Moran Shalev-Benami
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Martin Caffrey
- School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin D02 R590, Ireland
| |
Collapse
|
3
|
Smithers L, Olatunji S, Caffrey M. Bacterial Lipoprotein Posttranslational Modifications. New Insights and Opportunities for Antibiotic and Vaccine Development. Front Microbiol 2021; 12:788445. [PMID: 34950121 PMCID: PMC8689077 DOI: 10.3389/fmicb.2021.788445] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 11/16/2021] [Indexed: 12/17/2022] Open
Abstract
Lipoproteins are some of the most abundant proteins in bacteria. With a lipid anchor to the cell membrane, they function as enzymes, inhibitors, transporters, structural proteins, and as virulence factors. Lipoproteins activate the innate immune system and have biotechnological applications. The first lipoprotein was described by Braun and Rehn in 1969. Up until recently, however, work on lipoproteins has been sluggish, in part due to the challenges of handling proteins that are anchored to membranes by covalently linked lipids or are membrane integral. Activity in the area has quickened of late. In the past 5 years, high-resolution structures of the membrane enzymes of the canonical lipoprotein synthesis pathway have been determined, new lipoprotein types have been discovered and the enzymes responsible for their synthesis have been characterized biochemically. This has led to a flurry of activity aimed at developing novel antibiotics targeting these enzymes. In addition, surface exposed bacterial lipoproteins have been utilized as candidate vaccine antigens, and their potential to act as self-adjuvanting antigens is increasingly recognized. A summary of the latest developments in lipoproteins and their synthesis, as well as how this information is being exploited for therapeutic purposes is presented here.
Collapse
Affiliation(s)
- Luke Smithers
- School of Medicine, Trinity College Dublin, Dublin, Ireland
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| | - Samir Olatunji
- School of Medicine, Trinity College Dublin, Dublin, Ireland
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| | - Martin Caffrey
- School of Medicine, Trinity College Dublin, Dublin, Ireland
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| |
Collapse
|
4
|
El Rayes J, Rodríguez-Alonso R, Collet JF. Lipoproteins in Gram-negative bacteria: new insights into their biogenesis, subcellular targeting and functional roles. Curr Opin Microbiol 2021; 61:25-34. [PMID: 33667939 DOI: 10.1016/j.mib.2021.02.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 02/06/2023]
Abstract
Bacterial lipoproteins are globular proteins anchored to a membrane by a lipid moiety. By discovering new functions carried out by lipoproteins, recent research has highlighted the crucial roles played by these proteins in the cell envelope of Gram-negative bacteria. Here, after discussing the wide range of activities carried out by lipoproteins in the model bacterium Escherichia coli, we review new insights into the essential mechanisms involved in lipoprotein maturation, sorting and targeting to their final destination. A special attention will also be given to the recent identification of lipoproteins on the surface of E. coli and of other bacteria. The renewed interest in lipoproteins is driven by the need to identify novel targets for antibiotic development.
Collapse
Affiliation(s)
- Jessica El Rayes
- WELBIO, Avenue Hippocrate 75, 1200 Brussels, Belgium; de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
| | - Raquel Rodríguez-Alonso
- WELBIO, Avenue Hippocrate 75, 1200 Brussels, Belgium; de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
| | - Jean-François Collet
- WELBIO, Avenue Hippocrate 75, 1200 Brussels, Belgium; de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium.
| |
Collapse
|
5
|
Legood S, Boneca IG, Buddelmeijer N. Mode of action of lipoprotein modification enzymes-Novel antibacterial targets. Mol Microbiol 2021; 115:356-365. [PMID: 32979868 PMCID: PMC8048626 DOI: 10.1111/mmi.14610] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/10/2020] [Indexed: 01/04/2023]
Abstract
Lipoproteins are characterized by a fatty acid moiety at their amino-terminus through which they are anchored into membranes. They fulfill a variety of essential functions in bacterial cells, such as cell wall maintenance, virulence, efflux of toxic elements including antibiotics, and uptake of nutrients. The posttranslational modification process of lipoproteins involves the sequential action of integral membrane enzymes and phospholipids as acyl donors. In recent years, the structures of the lipoprotein modification enzymes have been solved by X-ray crystallography leading to a greater insight into their function and the molecular mechanism of the reactions. The catalytic domains of the enzymes are exposed to the periplasm or external milieu and are readily accessible to small molecules. Since the lipoprotein modification pathway is essential in proteobacteria, it is a potential target for the development of novel antibiotics. In this review, we discuss recent literature on the structural characterization of the enzymes, and the in vitro activity assays compatible with high-throughput screening for inhibitors, with perspectives on the development of new antimicrobial agents.
Collapse
Affiliation(s)
- Simon Legood
- Institut PasteurUnité Biologie et Génétique de la Paroi BactérienneParisFrance
- CNRS, UMR 2001 « Microbiologie intégrative et Moléculaire »ParisFrance
- INSERM Groupe AvenirParisFrance
- Université de ParisSorbonne Paris CitéParisFrance
| | - Ivo G. Boneca
- Institut PasteurUnité Biologie et Génétique de la Paroi BactérienneParisFrance
- CNRS, UMR 2001 « Microbiologie intégrative et Moléculaire »ParisFrance
- INSERM Groupe AvenirParisFrance
| | - Nienke Buddelmeijer
- Institut PasteurUnité Biologie et Génétique de la Paroi BactérienneParisFrance
- CNRS, UMR 2001 « Microbiologie intégrative et Moléculaire »ParisFrance
- INSERM Groupe AvenirParisFrance
| |
Collapse
|
6
|
Armbruster KM, Komazin G, Meredith TC. Bacterial lyso-form lipoproteins are synthesized via an intramolecular acyl chain migration. J Biol Chem 2020; 295:10195-10211. [PMID: 32471867 DOI: 10.1074/jbc.ra120.014000] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/22/2020] [Indexed: 01/08/2023] Open
Abstract
All bacterial lipoproteins share a variably acylated N-terminal cysteine residue. Gram-negative bacterial lipoproteins are triacylated with a thioether-linked diacylglycerol moiety and an N-acyl chain. The latter is transferred from a membrane phospholipid donor to the α-amino terminus by the enzyme lipoprotein N-acyltransferase (Lnt), using an active-site cysteine thioester covalent intermediate. Many Gram-positive Firmicutes also have N-acylated lipoproteins, but the enzymes catalyzing N-acylation remain uncharacterized. The integral membrane protein Lit (lipoprotein intramolecular transacylase) from the opportunistic nosocomial pathogen Enterococcus faecalis synthesizes a specific lysoform lipoprotein (N-acyl S-monoacylglycerol) chemotype by an unknown mechanism that helps this bacterium evade immune recognition by the Toll-like receptor 2 family complex. Here, we used a deuterium-labeled lipoprotein substrate with reconstituted Lit to investigate intramolecular acyl chain transfer. We observed that Lit transfers the sn-2 ester-linked lipid from the diacylglycerol moiety to the α-amino terminus without forming a covalent thioester intermediate. Utilizing Mut-Seq to analyze an alanine scan library of Lit alleles, we identified two stretches of functionally important amino acid residues containing two conserved histidines. Topology maps based on reporter fusion assays and cysteine accessibility placed both histidines in the extracellular half of the cytoplasmic membrane. We propose a general acid base-promoted catalytic mechanism, invoking direct nucleophilic attack by the substrate α-amino group on the sn-2 ester to form a cyclic tetrahedral intermediate that then collapses to produce lyso-lipoprotein. Lit is a unique example of an intramolecular transacylase differentiated from that catalyzed by Lnt, and provides insight into the heterogeneity of bacterial lipoprotein biosynthetic systems.
Collapse
Affiliation(s)
- Krista M Armbruster
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Gloria Komazin
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Timothy C Meredith
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA .,The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park Pennsylvania, USA
| |
Collapse
|