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Gabriel JM, Tan T, Rinauro DJ, Hsu CM, Buettner CJ, Gilmer M, Kaur A, McKenzie TL, Park M, Cohen S, Errico S, Wright AK, Chiti F, Vendruscolo M, Limbocker R. EGCG inactivates a pore-forming toxin by promoting its oligomerization and decreasing its solvent-exposed hydrophobicity. Chem Biol Interact 2023; 371:110307. [PMID: 36535315 DOI: 10.1016/j.cbi.2022.110307] [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: 09/18/2022] [Revised: 12/02/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Natural proteinaceous pore-forming agents can bind and permeabilize cell membranes, leading to ion dyshomeostasis and cell death. In the search for antidotes that can protect cells from peptide toxins, we discovered that the polyphenol epigallocatechin gallate (EGCG) interacts directly with melittin from honeybee venom, resulting in the elimination of its binding to the cell membrane and toxicity by markedly lowering the extent of its solvent-exposed hydrophobicity and promoting its oligomerization into larger species. These physicochemical parameters have also been shown to play a key role in the binding to cells of misfolded protein oligomers in a host of neurodegenerative diseases, where oligomer-membrane binding and associated toxicity have been shown to correlate negatively with oligomer size and positively with solvent-exposed hydrophobicity. For melittin, which is not an amyloid-forming protein and has a very distinct mechanism of toxicity compared to misfolded oligomers, we find that the size-hydrophobicity-toxicity relationship also rationalizes the pharmacological attenuation of melittin toxicity by EGCG. These results highlight the importance of the physicochemical properties of pore forming agents in mediating their interactions with cell membranes and suggest a possible therapeutic approach based on compounds with a similar mechanism of action as EGCG.
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Affiliation(s)
- Justus M Gabriel
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Thomas Tan
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Dillon J Rinauro
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Claire M Hsu
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Caleb J Buettner
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Marshall Gilmer
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Amrita Kaur
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Tristan L McKenzie
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Martin Park
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Sophie Cohen
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Silvia Errico
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK; Department of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence, Italy
| | - Aidan K Wright
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence, Italy
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Ryan Limbocker
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA.
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Mishra S, Kundu N, Pramanick I, Kumar A, Chattopadhyay K, Dutta S. Structural insights into thermostable direct hemolysin of Vibrio parahaemolyticus using single-particle cryo-EM. Proteins 2023; 91:137-146. [PMID: 36000388 DOI: 10.1002/prot.26416] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/09/2022] [Accepted: 08/12/2022] [Indexed: 01/07/2023]
Abstract
Thermostable direct hemolysin (TDH) is a ~19 kDa, hemolytic pore-forming toxin from the gram-negative marine bacterium Vibrio parahaemolyticus, one of the causative agents of seafood-borne acute gastroenteritis and septicemia. Previous studies have established that TDH exists as a tetrameric assembly in physiological state; however, there is limited knowledge regarding the molecular arrangement of its disordered N-terminal region (NTR)-the absence of which has been shown to compromise TDH's hemolytic and cytotoxic abilities. In our current study, we have employed single-particle cryo-electron microscopy to resolve the solution-state structures of wild-type TDH and a TDH construct with deletion of the NTR (NTD), in order to investigate structural aspects of NTR on the overall tetrameric architecture. We observed that both TDH and NTD electron density maps, resolved at global resolutions of 4.5 and 4.2 Å, respectively, showed good correlation in their respective oligomeric architecture. Additionally, we were able to locate extra densities near the pore opening of TDH which might correspond to the disordered NTR. Surprisingly, under cryogenic conditions, we were also able to observe novel supramolecular assemblies of TDH tetramers, which we were able to resolve to 4.3 Å. We further investigated the tetrameric and inter-tetrameric interaction interfaces to elaborate upon the key residues involved in both TDH tetramers and TDH super assemblies. Our current structural study will aid in understanding the mechanistic aspects of this pore-forming toxin and the role of its disordered NTR in membrane interaction.
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Affiliation(s)
- Suman Mishra
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Nidhi Kundu
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India
| | - Ishika Pramanick
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Anil Kumar
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Kausik Chattopadhyay
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India
| | - Somnath Dutta
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
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3
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Palacios-Ortega J, Amigot-Sánchez R, García-Montoya C, Gorše A, Heras-Márquez D, García-Linares S, Martínez-del-Pozo Á, Slotte JP. Determination of the boundary lipids of sticholysins using tryptophan quenching. Sci Rep 2022; 12:17328. [PMID: 36243747 PMCID: PMC9569322 DOI: 10.1038/s41598-022-21750-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 09/30/2022] [Indexed: 01/10/2023] Open
Abstract
Sticholysins are α-pore-forming toxins produced by the sea-anemone Stichodactyla helianthus. These toxins exert their activity by forming pores on sphingomyelin-containing membranes. Recognition of sphingomyelin by sticholysins is required to start the process of pore formation. Sphingomyelin recognition is coupled with membrane binding and followed by membrane penetration and oligomerization. Many features of these processes are known. However, the extent of contact with each of the different kinds of lipids present in the membrane has received little attention. To delve into this question, we have used a phosphatidylcholine analogue labeled at one of its acyl chains with a doxyl moiety, a known quencher of tryptophan emission. Here we present evidence for the contact of sticholysins with phosphatidylcholine lipids in the sticholysin oligomer, and for how each sticholysin isotoxin is affected differently by the inclusion of cholesterol in the membrane. Furthermore, using phosphatidylcholine analogs that were labeled at different positions of their structure (acyl chains and headgroup) in combination with a variety of sticholysin mutants, we also investigated the depth of the tryptophan residues of sticholysins in the bilayer. Our results indicate that the position of the tryptophan residues relative to the membrane normal is deeper when cholesterol is absent from the membrane.
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Affiliation(s)
- Juan Palacios-Ortega
- grid.13797.3b0000 0001 2235 8415Biochemistry Department, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland ,grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - Rafael Amigot-Sánchez
- grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - Carmen García-Montoya
- grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - Ana Gorše
- grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - Diego Heras-Márquez
- grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - Sara García-Linares
- grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - Álvaro Martínez-del-Pozo
- grid.4795.f0000 0001 2157 7667Departamento de Bioquímica y Biología Molecular, Universidad Complutense, Madrid, Spain
| | - J. Peter Slotte
- grid.13797.3b0000 0001 2235 8415Biochemistry Department, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
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Šolinc G, Švigelj T, Omersa N, Snoj T, Pirc K, Žnidaršič N, Yamaji-Hasegawa A, Kobayashi T, Anderluh G, Podobnik M. Pore-forming moss protein bryoporin is structurally and mechanistically related to actinoporins from evolutionarily distant cnidarians. J Biol Chem 2022; 298:102455. [PMID: 36063994 PMCID: PMC9526159 DOI: 10.1016/j.jbc.2022.102455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 10/26/2022] Open
Abstract
Pore-forming proteins perforate lipid membranes and consequently affect their integrity and cell fitness. Therefore, it is not surprising that many of these proteins from bacteria, fungi, or certain animals act as toxins. While pore-forming proteins have also been found in plants, there is little information on their molecular structure and mode of action. Bryoporin is a protein from the moss Physcomitrium patens, and its corresponding gene was found to be upregulated by various abiotic stresses, especially dehydration, as well as upon fungal infection. Based on the amino acid sequence, it was suggested that bryoporin was related to the actinoporin family of pore-forming proteins, originally discovered in sea anemones. Here, we provide the first detailed structural and functional analysis of this plant cytolysin. The crystal structure of the monomeric bryoporin is highly similar to those of actinoporins. Our cryo-EM analysis of its pores showed an actinoporin-like octameric structure, thereby revealing a close kinship of proteins from evolutionarily distant organisms. This was further confirmed by our observation of bryoporin's preferential binding to and formation of pores in membranes containing animal sphingolipids, such as sphingomyelin and ceramide phosphoethanolamine; however, its binding affinity was weaker than that of actinoporin equinatoxin II. We determined bryoporin did not bind to major sphingolipids found in fungi or plants, and its membrane-binding and pore-forming activity were enhanced by various sterols. Our results suggest that bryoporin could represent a part of the moss defense arsenal, acting as a pore-forming toxin against membranes of potential animal pathogens, parasites, or predators.
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Affiliation(s)
- Gašper Šolinc
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | - Tomaž Švigelj
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | - Neža Omersa
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | - Tina Snoj
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | - Katja Pirc
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | - Nada Žnidaršič
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, Ljubljana, Slovenia
| | | | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, 2-1, Hirosawa, Wako-shi, Saitama 351-0198, Japan; UMR 7021 CNRS, Université de Strasbourg, Illkirch, France
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | - Marjetka Podobnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia.
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Gupta T, Mondal AK, Pani I, Chattopadhyay K, Pal SK. Elucidating liquid crystal-aqueous interface for the study of cholesterol-mediated action of a β-barrel pore forming toxin. SOFT MATTER 2022; 18:5293-5301. [PMID: 35790122 DOI: 10.1039/d2sm00447j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Pore-forming toxins (PFTs) produced by pathogenic bacteria serve as prominent virulence factors with potent cell-killing activity. Most of the β-barrel PFTs form transmembrane oligomeric pores in the membrane lipid bilayer in the presence of cholesterol. The pore-formation mechanisms of the PFTs highlight well-orchestrated regulated events in the membrane environment, which involve dramatic changes in the protein structure and organization. Also, concerted crosstalk between protein and membrane lipid components appears to play crucial roles in the process. Membrane-damaging lesions formed by the pore assembly of the PFTs would also be expected to impose drastic alterations in the membrane organization, details of which remain obscure in most of the cases. Prior reports have established that aqueous interfaces of liquid crystals (LCs) offer promise as responsive interfaces for biomolecular events (at physiologically relevant concentrations), which can be visualized as optical signals. Inspired by this, herein, we sought to understand the lipid membrane interactions of a β-barrel PFT i.e., Vibrio cholerae cytolysin (VCC), using LC-aqueous interfaces. Our results show the formation of dendritic patterns upon the addition of VCC to the lipid embedded with cholesterol over the LC film. In contrast, we did not observe any LC reorientation upon the addition of VCC to the lipid-laden LC-aqueous interface in the absence of cholesterol. An array of techniques such as polarizing optical microscopy (POM), atomic force microscopy (AFM), and fluorescence measurements were utilized to decipher the LC response to the lipid interactions of VCC occurring at these interfaces. Altogether, the results obtained from our study provide a novel platform to explore the mechanistic aspects of the protein-membrane interactions, in the process of membrane pore-formation by the membrane-damaging PFTs.
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Affiliation(s)
- Tarang Gupta
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
| | - Anish Kumar Mondal
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
| | - Ipsita Pani
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
| | - Kausik Chattopadhyay
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
| | - Santanu Kumar Pal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector-81, SAS Nagar, Mohali 140306, India.
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Cytolysin A (ClyA): A Bacterial Virulence Factor with Potential Applications in Nanopore Technology, Vaccine Development, and Tumor Therapy. Toxins (Basel) 2022; 14:toxins14020078. [PMID: 35202106 PMCID: PMC8880466 DOI: 10.3390/toxins14020078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 12/26/2022] Open
Abstract
Cytolysin A (ClyA) is a pore-forming toxin that is produced by some bacteria from the Enterobacteriaceae family. This review provides an overview of the current state of knowledge regarding ClyA, including the prevalence of the encoding gene and its transcriptional regulation, the secretion pathway used by the protein, and the mechanism of protein assembly, and highlights potential applications of ClyA in biotechnology. ClyA expression is regulated at the transcriptional level, primarily in response to environmental stressors, and ClyA can exist stably both as a soluble monomer and as an oligomeric membrane complex. At high concentrations, ClyA induces cytolysis, whereas at low concentrations ClyA can affect intracellular signaling. ClyA is secreted in outer membrane vesicles (OMVs), which has important implications for biotechnology applications. For example, the native pore-forming ability of ClyA suggests that it could be used as a component of nanopore-based technologies, such as sequencing platforms. ClyA has also been exploited in vaccine development owing to its ability to present antigens on the OMV surface and provoke a robust immune response. In addition, ClyA alone or OMVs carrying ClyA fusion proteins have been investigated for their potential use as anti-tumor agents.
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Sengupta N, Mondal AK, Mishra S, Chattopadhyay K, Dutta S. Single-particle cryo-EM reveals conformational variability of the oligomeric VCC β-barrel pore in a lipid bilayer. J Cell Biol 2021; 220:212683. [PMID: 34617964 PMCID: PMC8504180 DOI: 10.1083/jcb.202102035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 08/25/2021] [Accepted: 09/19/2021] [Indexed: 11/22/2022] Open
Abstract
Vibrio cholerae cytolysin (VCC) is a water-soluble, membrane-damaging, pore-forming toxin (PFT) secreted by pathogenic V. cholerae, which causes eukaryotic cell death by altering the plasma membrane permeability. VCC self-assembles on the cell surface and undergoes a dramatic conformational change from prepore to heptameric pore structure. Over the past few years, several high-resolution structures of detergent-solubilized PFTs have been characterized. However, high-resolution structural characterization of small β-PFTs in a lipid environment is still rare. Therefore, we used single-particle cryo-EM to characterize the structure of the VCC oligomer in large unilamellar vesicles, which is the first atomic-resolution cryo-EM structure of VCC. From our study, we were able to provide the first documented visualization of the rim domain amino acid residues of VCC interacting with lipid membrane. Furthermore, cryo-EM characterization of lipid bilayer–embedded VCC suggests interesting conformational variabilities, especially in the transmembrane channel, which could have a potential impact on the pore architecture and assist us in understanding the pore formation mechanism.
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Affiliation(s)
- Nayanika Sengupta
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Anish Kumar Mondal
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Punjab, India
| | - Suman Mishra
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Kausik Chattopadhyay
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Punjab, India
| | - Somnath Dutta
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
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Mondal AK, Chattopadhyay K. Structures and functions of the membrane-damaging pore-forming proteins. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 128:241-288. [PMID: 35034720 DOI: 10.1016/bs.apcsb.2021.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Pore-forming proteins (PFPs) of the diverse life forms have emerged as the potent cell-killing entities owing to their specialized membrane-damaging properties. PFPs have the unique ability to perforate the plasma membranes of their target cells, and they exert this functionality by creating oligomeric pores in the membrane lipid bilayer. Pathogenic bacteria employ PFPs as toxins to execute their virulence mechanisms, whereas in the higher vertebrates PFPs are deployed as the part of the immune system and to generate inflammatory responses. PFPs are the unique dimorphic proteins that are generally synthesized as water-soluble molecules, and transform into membrane-inserted oligomeric pore assemblies upon interacting with the target membranes. In spite of sharing very little sequence similarity, PFPs from diverse organisms display incredible structural similarity. Yet, at the same time, structure-function mechanisms of the PFPs document remarkable versatility. Such notions establish PFPs as the fascinating model system to explore variety of unsolved issues pertaining to the structure-function paradigm of the proteins that interact and act in the membrane environment. In this article, we discuss our current understanding regarding the structural basis of the pore-forming functions of the diverse class of PFPs. We attempt to highlight the similarities and differences in their structures, membrane pore-formation mechanisms, and their implications for the various biological processes, ranging from the bacterial virulence mechanisms to the inflammatory immune response generation in the higher animals.
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Affiliation(s)
- Anish Kumar Mondal
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India
| | - Kausik Chattopadhyay
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, Punjab, India.
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Palacios-Ortega J, García-Linares S, Rivera-de-Torre E, Heras-Márquez D, Gavilanes JG, Slotte JP, Martínez-Del-Pozo Á. Structural foundations of sticholysin functionality. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140696. [PMID: 34246789 DOI: 10.1016/j.bbapap.2021.140696] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 01/22/2023]
Abstract
Actinoporins constitute a family of α pore-forming toxins produced by sea anemones. The soluble fold of these proteins consists of a β-sandwich flanked by two α-helices. Actinoporins exert their activity by specifically recognizing sphingomyelin at their target membranes. Once there, they penetrate the membrane with their N-terminal α-helices, a process that leads to the formation of cation-selective pores. These pores kill the target cells by provoking an osmotic shock on them. In this review, we examine the role and relevance of the structural features of actinoporins, down to the residue level. We look at the specific amino acids that play significant roles in the function of actinoporins and their fold. Particular emphasis is given to those residues that display a high degree of conservation across the actinoporin sequences known to date. In light of the latest findings in the field, the membrane requirements for pore formation, the effect of lipid composition, and the process of pore formation are also discussed.
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Affiliation(s)
- Juan Palacios-Ortega
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense, Madrid, Spain; Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland.
| | - Sara García-Linares
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense, Madrid, Spain
| | - Esperanza Rivera-de-Torre
- Department of Biochemistry and Biotechnology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Diego Heras-Márquez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense, Madrid, Spain
| | - José G Gavilanes
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense, Madrid, Spain
| | - J Peter Slotte
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Álvaro Martínez-Del-Pozo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense, Madrid, Spain
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The molecular mechanisms of listeriolysin O-induced lipid membrane damage. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183604. [PMID: 33722646 DOI: 10.1016/j.bbamem.2021.183604] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/05/2021] [Accepted: 03/05/2021] [Indexed: 12/22/2022]
Abstract
Listeria monocytogenes is an intracellular food-borne pathogen that causes listeriosis, a severe and potentially life-threatening disease. Listeria uses a number of virulence factors to proliferate and spread to various cells and tissues. In this process, three bacterial virulence factors, the pore-forming protein listeriolysin O and phospholipases PlcA and PlcB, play a crucial role. Listeriolysin O belongs to a family of cholesterol-dependent cytolysins that are mostly expressed by gram-positive bacteria. Its unique structural features in an otherwise conserved three-dimensional fold, such as the acidic triad and proline-glutamate-serine-threonine-like sequence, enable the regulation of its intracellular activity as well as distinct extracellular functions. The stability of listeriolysin O is pH- and temperature-dependent, and this provides another layer of control of its activity in cells. Moreover, many recent studies have demonstrated a unique mechanism of pore formation by listeriolysin O, i.e., the formation of arc-shaped oligomers that can subsequently fuse to form membrane defects of various shapes and sizes. During listerial invasion of host cells, these membrane defects can disrupt phagosome membranes, allowing bacteria to escape into the cytosol and rapidly multiply. The activity of listeriolysin O is profoundly dependent on the amount and accessibility of cholesterol in the lipid membrane, which can be modulated by the phospholipase PlcB. All these prominent features of listeriolysin O play a role during different stages of the L. monocytogenes life cycle by promoting the proliferation of the pathogen while mitigating excessive damage to its replicative niche in the cytosol of the host cell.
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Pore-forming proteins: From defense factors to endogenous executors of cell death. Chem Phys Lipids 2020; 234:105026. [PMID: 33309552 DOI: 10.1016/j.chemphyslip.2020.105026] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 02/06/2023]
Abstract
Pore-forming proteins (PFPs) and small antimicrobial peptides (AMPs) represent a large family of molecules with the common ability to punch holes in cell membranes to alter their permeability. They play a fundamental role as infectious bacteria's defensive tools against host's immune system and as executors of endogenous machineries of regulated cell death in eukaryotic cells. Despite being highly divergent in primary sequence and 3D structure, specific folds of pore-forming domains have been conserved. In fact, pore formation is considered an ancient mechanism that takes place through a general multistep process involving: membrane partitioning and insertion, oligomerization and pore formation. However, different PFPs and AMPs assemble and form pores following different mechanisms that could end up either in the formation of protein-lined or protein-lipid pores. In this review, we analyze the current findings in the mechanism of action of different PFPs and AMPs that support a wide role of membrane pore formation in nature. We also provide the newest insights into the development of state-of-art techniques that have facilitated the characterization of membrane pores. To understand the physiological role of these peptides/proteins or develop clinical applications, it is essential to uncover the molecular mechanism of how they perforate membranes.
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12
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Molecular Dynamics Study of Lipid and Cholesterol Reorganization Due to Membrane Binding and Pore Formation by Listeriolysin O. J Membr Biol 2020; 253:535-550. [DOI: 10.1007/s00232-020-00148-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Accepted: 10/10/2020] [Indexed: 12/20/2022]
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13
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The bright and dark sides of protein conformational switches and the unifying forces of infections. Commun Biol 2020; 3:382. [PMID: 32669705 PMCID: PMC7363679 DOI: 10.1038/s42003-020-1115-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 06/29/2020] [Indexed: 12/19/2022] Open
Abstract
It is now established that a protein can switch between multiple conformations to enable altered functions. Several pathogens including SARS COV2 utilize context-dependent conformational switches of particular proteins to invade host membrane to establish infections. In this perspective, we first discuss the understanding of the conformational switch of a protein towards the productive infections as a dark side of nature. Next, the unexplored binary combination of the sequences of SARS COV2 spike protein and the similarity with diverse pathogen derived proteins have been discussed to obtain novel molecular insights into the process of infection. Sannigrahi et al. discuss conformational switching that allows proteins to alter their conformation, aiding in pathogenesis by enabling cellular entry of viruses and bacterial toxins. Focussing on fusion domain of the Spike glycoprotein of SARS COV2 virus, they identify similar “switching sequences” present in diverse pathogen derived proteins.
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14
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The Cytocidal Spectrum of Bacillus thuringiensis Toxins: From Insects to Human Cancer Cells. Toxins (Basel) 2020; 12:toxins12050301. [PMID: 32384723 PMCID: PMC7291302 DOI: 10.3390/toxins12050301] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/27/2020] [Accepted: 05/02/2020] [Indexed: 12/29/2022] Open
Abstract
Bacillus thuringiensis (Bt) is a ubiquitous bacterium in soils, insect cadavers, phylloplane, water, and stored grain, that produces several proteins, each one toxic to different biological targets such as insects, nematodes, mites, protozoa, and mammalian cells. Most Bt toxins identify their particular target through the recognition of specific cell membrane receptors. Cry proteins are the best-known toxins from Bt and a great amount of research has been published. Cry are cytotoxic to insect larvae that affect important crops recognizing specific cell membrane receptors such as cadherin, aminopeptidase-N, and alkaline phosphatase. Furthermore, some Cry toxins such as Cry4A, Cry4B, and Cry11A act synergistically with Cyt toxins against dipteran larvae vectors of human disease. Research developed with Cry proteins revealed that these toxins also could kill human cancer cells through the interaction with specific receptors. Parasporins are a small group of patented toxins that may or may not have insecticidal activity. These proteins could kill a wide variety of mammalian cancer cells by recognizing specific membrane receptors, just like Cry toxins do. Surface layer proteins (SLP), unlike the other proteins produced by Bt, are also produced by most bacteria and archaebacteria. It was recently demonstrated that SLP produced by Bt could interact with membrane receptors of insect and human cancer cells to kill them. Cyt toxins have a structure that is mostly unrelated to Cry toxins; thereby, other mechanisms of action have been reported to them. These toxins affect mainly mosquitoes that are vectors of human diseases like Anopheles spp (malaria), Aedes spp (dengue, zika, and chikungunya), and Culex spp (Nile fever and Rift Valley fever), respectively. In addition to the Cry, Cyt, and parasporins toxins produced during spore formation as inclusion bodies, Bt strains also produce Vip (Vegetative insecticidal toxins) and Sip (Secreted insecticidal proteins) toxins with insecticidal activity during their vegetative growth phase.
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15
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Liposomal membrane permeability assessment by fluorescence techniques: Main permeabilizing agents, applications and challenges. Int J Pharm 2020; 580:119198. [PMID: 32169353 DOI: 10.1016/j.ijpharm.2020.119198] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/19/2020] [Accepted: 03/02/2020] [Indexed: 01/08/2023]
Abstract
Liposomes are lipid vesicles made of one or multiple lipid bilayers surrounding an internal aqueous core. They are broadly employed as models to study membrane structure and properties. Among these properties, liposome membrane permeability is crucial and widely assessed by fluorescence techniques. The first part of this review is devoted to describe the various techniques used for membrane permeability assessment. Attention is paid to fluorescence techniques based on vesicle leakage of self-quenching probes, dye/quencher pair or cation/ligand pair. Secondly, the membrane-active agents inducing membrane permeabilization is presented and details on their mechanisms of action are given. Emphasis is also laid on the intrinsic and extrinsic factors that can modulate the membrane permeability. Hence, a suitable liposomal membrane should be formulated according to the aim of the study and its application.
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16
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Mariano G, Trunk K, Williams DJ, Monlezun L, Strahl H, Pitt SJ, Coulthurst SJ. A family of Type VI secretion system effector proteins that form ion-selective pores. Nat Commun 2019; 10:5484. [PMID: 31792213 PMCID: PMC6889166 DOI: 10.1038/s41467-019-13439-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 11/05/2019] [Indexed: 12/25/2022] Open
Abstract
Type VI secretion systems (T6SSs) are nanomachines widely used by bacteria to deliver toxic effector proteins directly into neighbouring cells. However, the modes of action of many effectors remain unknown. Here we report that Ssp6, an anti-bacterial effector delivered by a T6SS of the opportunistic pathogen Serratia marcescens, is a toxin that forms ion-selective pores. Ssp6 inhibits bacterial growth by causing depolarisation of the inner membrane in intoxicated cells, together with increased outer membrane permeability. Reconstruction of Ssp6 activity in vitro demonstrates that it forms cation-selective pores. A survey of bacterial genomes reveals that genes encoding Ssp6-like effectors are widespread in Enterobacteriaceae and often linked with T6SS genes. We conclude that Ssp6 and similar proteins represent a new family of T6SS-delivered anti-bacterial effectors.
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Affiliation(s)
- Giuseppina Mariano
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dow St, Dundee, DD1 5EH, UK
| | - Katharina Trunk
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dow St, Dundee, DD1 5EH, UK
| | - David J Williams
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dow St, Dundee, DD1 5EH, UK
| | - Laura Monlezun
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dow St, Dundee, DD1 5EH, UK
| | - Henrik Strahl
- Centre for Bacterial Cell Biology, Newcastle University, Richardson Road, Newcastle-upon-Tyne, NE2 4AX, UK
| | - Samantha J Pitt
- School of Medicine, University of St Andrews, North Haugh, St Andrews, KY16 9TF, UK
| | - Sarah J Coulthurst
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dow St, Dundee, DD1 5EH, UK.
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Mondal AK, Chattopadhyay K. Taking Toll on Membranes: Curious Cases of Bacterial β-Barrel Pore-Forming Toxins. Biochemistry 2019; 59:163-170. [DOI: 10.1021/acs.biochem.9b00783] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Anish Kumar Mondal
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Manauli, Mohali, Punjab 140306, India
| | - Kausik Chattopadhyay
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Manauli, Mohali, Punjab 140306, India
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18
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Mesa-Galloso H, Valiente PA, Valdés-Tresanco ME, Epand RF, Lanio ME, Epand RM, Alvarez C, Tieleman DP, Ros U. Membrane Remodeling by the Lytic Fragment of SticholysinII: Implications for the Toroidal Pore Model. Biophys J 2019; 117:1563-1576. [PMID: 31587828 DOI: 10.1016/j.bpj.2019.09.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 09/07/2019] [Accepted: 09/09/2019] [Indexed: 01/15/2023] Open
Abstract
Sticholysins are pore-forming toxins of biomedical interest and represent a prototype of proteins acting through the formation of protein-lipid or toroidal pores. Peptides spanning the N-terminus of sticholysins can mimic their permeabilizing activity and, together with the full-length toxins, have been used as a tool to understand the mechanism of pore formation in membranes. However, the lytic mechanism of these peptides and the lipid shape modulating their activity are not completely clear. In this article, we combine molecular dynamics simulations and experimental biophysical tools to dissect different aspects of the pore-forming mechanism of StII1-30, a peptide derived from the N-terminus of sticholysin II (StII). With this combined approach, membrane curvature induction and flip-flop movement of the lipids were identified as two important membrane remodeling steps mediated by StII1-30. Pore formation by this peptide was enhanced by the presence of the negatively curved lipid phosphatidylethanolamine in membranes. This lipid emerged not only as a facilitator of membrane interactions but also as a structural element of the StII1-30 pore that is recruited to the ring upon its assembly. Collectively, these, to our knowledge, new findings support a toroidal model for the architecture of the pore formed by StII1-30 and provide new molecular insight into the role of phosphatidylethanolamine as a membrane component that can easily integrate into the ring of toroidal pores, thus probably aiding in their stabilization. This study contributes to a better understanding of the molecular mechanism underlying the permeabilizing activity of StII1-30 and peptides or proteins acting via a toroidal pore mechanism and offers an informative framework for the optimization of the biomedical application of this and similar molecules.
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Affiliation(s)
- Haydee Mesa-Galloso
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada; Center for Protein Studies, Faculty of Biology, University of Havana, Havana, Cuba
| | - Pedro A Valiente
- Center for Protein Studies, Faculty of Biology, University of Havana, Havana, Cuba
| | - Mario E Valdés-Tresanco
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada; Center for Protein Studies, Faculty of Biology, University of Havana, Havana, Cuba
| | - Raquel F Epand
- Department of Biochemistry and Biomedical Sciences, Health Science Center, McMaster University, Hamilton, Ontario, Canada
| | - Maria E Lanio
- Center for Protein Studies, Faculty of Biology, University of Havana, Havana, Cuba
| | - Richard M Epand
- Department of Biochemistry and Biomedical Sciences, Health Science Center, McMaster University, Hamilton, Ontario, Canada
| | - Carlos Alvarez
- Center for Protein Studies, Faculty of Biology, University of Havana, Havana, Cuba
| | - D Peter Tieleman
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada.
| | - Uris Ros
- Center for Protein Studies, Faculty of Biology, University of Havana, Havana, Cuba; Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany.
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19
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Omersa N, Podobnik M, Anderluh G. Inhibition of Pore-Forming Proteins. Toxins (Basel) 2019; 11:E545. [PMID: 31546810 PMCID: PMC6784129 DOI: 10.3390/toxins11090545] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/27/2019] [Accepted: 09/10/2019] [Indexed: 12/16/2022] Open
Abstract
Perforation of cellular membranes by pore-forming proteins can affect cell physiology, tissue integrity, or immune response. Since many pore-forming proteins are toxins or highly potent virulence factors, they represent an attractive target for the development of molecules that neutralize their actions with high efficacy. There has been an assortment of inhibitors developed to specifically obstruct the activity of pore-forming proteins, in addition to vaccination and antibiotics that serve as a plausible treatment for the majority of diseases caused by bacterial infections. Here we review a wide range of potential inhibitors that can specifically and effectively block the activity of pore-forming proteins, from small molecules to more specific macromolecular systems, such as synthetic nanoparticles, antibodies, antibody mimetics, polyvalent inhibitors, and dominant negative mutants. We discuss their mechanism of inhibition, as well as advantages and disadvantages.
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Affiliation(s)
- Neža Omersa
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
| | - Marjetka Podobnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
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20
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Hammond K, Lewis H, Faruqui N, Russell C, Hoogenboom BW, Ryadnov MG. Helminth Defense Molecules as Design Templates for Membrane Active Antibiotics. ACS Infect Dis 2019; 5:1471-1479. [PMID: 31117348 DOI: 10.1021/acsinfecdis.9b00157] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A design template for membrane active antibiotics against microbial and tumor cells is described. The template is an amino acid sequence that combines the properties of helminth defense molecules, which are not cytolytic, with the properties of host-defense peptides, which disrupt microbial membranes. Like helminth defense molecules, the template folds into an amphipathic helix in both mammalian host and microbial phospholipid membranes. Unlike these molecules, the template exhibits antimicrobial and anticancer properties that are comparable to those of antimicrobial and anticancer antibiotics. The selective antibiotic activity of the template builds upon a functional synergy between three distinctive faces of the helix, which is in contrast to two faces of membrane-disrupting amphipathic structures. This synergy enables the template to adapt pore formation mechanisms according to the nature of the target membrane, inducing the lysis of microbial and tumor cells.
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Affiliation(s)
- Katharine Hammond
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
- Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
- London Centre for Nanotechnology, University College London, Gordon Street, London WC1H 0AH, United Kingdom
| | - Helen Lewis
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - Nilofar Faruqui
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - Craig Russell
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - Bart W. Hoogenboom
- Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
- London Centre for Nanotechnology, University College London, Gordon Street, London WC1H 0AH, United Kingdom
| | - Maxim G. Ryadnov
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
- Department of Physics, King’s College London, Strand Lane, London WC2R, United Kingdom
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21
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Morton CJ, Sani MA, Parker MW, Separovic F. Cholesterol-Dependent Cytolysins: Membrane and Protein Structural Requirements for Pore Formation. Chem Rev 2019; 119:7721-7736. [DOI: 10.1021/acs.chemrev.9b00090] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Craig J. Morton
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Marc-Antoine Sani
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Michael W. Parker
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, Victoria 3010, Australia
- St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
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22
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Pharmacological Targeting of Pore-Forming Toxins as Adjunctive Therapy for Invasive Bacterial Infection. Toxins (Basel) 2018; 10:toxins10120542. [PMID: 30562923 PMCID: PMC6316385 DOI: 10.3390/toxins10120542] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 12/10/2018] [Accepted: 12/14/2018] [Indexed: 12/23/2022] Open
Abstract
For many of the most important human bacterial infections, invasive disease severity is fueled by the cell damaging and pro-inflammatory effects of secreted pore-forming toxins (PFTs). Isogenic PFT-knockout mutants, e.g., Staphylococcus aureus lacking α-toxin or Streptococcus pneumoniae deficient in pneumolysin, show attenuation in animal infection models. This knowledge has inspired multi-model investigations of strategies to neutralize PFTs or counteract their toxicity as a novel pharmacological approach to ameliorate disease pathogenesis in clinical disease. Promising examples of small molecule, antibody or nanotherapeutic drug candidates that directly bind and neutralize PFTs, block their oligomerization or membrane receptor interactions, plug establishment membrane pores, or boost host cell resiliency to withstand PFT action have emerged. The present review highlights these new concepts, with a special focus on β-PFTs produced by leading invasive human Gram-positive bacterial pathogens. Such anti-virulence therapies could be applied as an adjunctive therapy to antibiotic-sensitive and -resistant strains alike, and further could be free of deleterious effects that deplete the normal microflora.
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23
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Yap WY, Hwang JS. Response of Cellular Innate Immunity to Cnidarian Pore-Forming Toxins. Molecules 2018; 23:E2537. [PMID: 30287801 PMCID: PMC6222686 DOI: 10.3390/molecules23102537] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 09/24/2018] [Accepted: 09/28/2018] [Indexed: 12/11/2022] Open
Abstract
A group of stable, water-soluble and membrane-bound proteins constitute the pore forming toxins (PFTs) in cnidarians. They interact with membranes to physically alter the membrane structure and permeability, resulting in the formation of pores. These lesions on the plasma membrane causes an imbalance of cellular ionic gradients, resulting in swelling of the cell and eventually its rupture. Of all cnidarian PFTs, actinoporins are by far the best studied subgroup with established knowledge of their molecular structure and their mode of pore-forming action. However, the current view of necrotic action by actinoporins may not be the only mechanism that induces cell death since there is increasing evidence showing that pore-forming toxins can induce either necrosis or apoptosis in a cell-type, receptor and dose-dependent manner. In this review, we focus on the response of the cellular immune system to the cnidarian pore-forming toxins and the signaling pathways that might be involved in these cellular responses. Since PFTs represent potential candidates for targeted toxin therapy for the treatment of numerous cancers, we also address the challenge to overcoming the immunogenicity of these toxins when used as therapeutics.
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Affiliation(s)
- Wei Yuen Yap
- Department of Biological Sciences, School of Science and Technology, Sunway University, No. 5 Jalan Universiti, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia.
| | - Jung Shan Hwang
- Department of Medical Sciences, School of Healthcare and Medical Sciences, Sunway University, No. 5 Jalan Universiti, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia.
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24
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Christie MP, Johnstone BA, Tweten RK, Parker MW, Morton CJ. Cholesterol-dependent cytolysins: from water-soluble state to membrane pore. Biophys Rev 2018; 10:1337-1348. [PMID: 30117093 DOI: 10.1007/s12551-018-0448-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 08/07/2018] [Indexed: 12/22/2022] Open
Abstract
The cholesterol-dependent cytolysins (CDCs) are a family of bacterial toxins that are important virulence factors for a number of pathogenic Gram-positive bacterial species. CDCs are secreted as soluble, stable monomeric proteins that bind specifically to cholesterol-rich cell membranes, where they assemble into well-defined ring-shaped complexes of around 40 monomers. The complex then undergoes a concerted structural change, driving a large pore through the membrane, potentially lysing the target cell. Understanding the details of this process as the protein transitions from a discrete monomer to a complex, membrane-spanning protein machine is an ongoing challenge. While many of the details have been revealed, there are still questions that remain unanswered. In this review, we present an overview of some of the key features of the structure and function of the CDCs, including the structure of the secreted monomers, the process of interaction with target membranes, and the transition from bound monomers to complete pores. Future directions in CDC research and the potential of CDCs as research tools will also be discussed.
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Affiliation(s)
- Michelle P Christie
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Bronte A Johnstone
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Rodney K Tweten
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - Michael W Parker
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
- Australian Cancer Research Foundation Rational Drug Discovery Centre, St Vincent's Institute of Medical Research, Fitzroy, VIC, 3065, Australia.
| | - Craig J Morton
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
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25
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Chen LL, Xie J, Cao DD, Jia N, Li YJ, Sun H, Li WF, Hu B, Chen Y, Zhou CZ. The pore-forming protein Aep1 is an innate immune molecule that prevents zebrafish from bacterial infection. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 82:49-54. [PMID: 29317232 DOI: 10.1016/j.dci.2018.01.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 01/06/2018] [Accepted: 01/06/2018] [Indexed: 06/07/2023]
Abstract
Following the Aeromonas hydrophila aerolysin, various aerolysin-like pore-forming proteins have been identified from bacteria to vertebrates. We have recently reported the mechanism of receptor recognition and in vitro pore-formation of a zebrafish aerolysin-like protein Dln1/Aep1. However, the physiological function of Aep1 remains unknown. Here we detected that aep1 gene is constitutively expressed in various immune-related tissues of adult zebrafish; and moreover, its expression is significantly up-regulated upon bacterial challenge, indicating its involvement in antimicrobial infection. Pre-injection of recombinant Aep1 into the infected zebrafish greatly accelerated the clearance of bacteria, resulting in significantly increased survival rate. Meanwhile, the induced expression of cytokines such as interleukin IL-1β and tumor necrosis factor TNF-α in zebrafish upon injection of recombinant Aep1 suggested that Aep1 may be a pro-inflammatory protein that triggers the antimicrobial immune responses. However, compared to the overproduction of these cytokines in the infected zebrafish, pre-injection of Aep1 could significantly reduce the expression level of these cytokines, accompanying with a reduced bacterial load. Moreover, the expression profiles through the developmental stages of zebrafish demonstrated that aep1 is activated at the very early stage prior to the maturation of adaptive immune system. Altogether, our findings proved that Aep1 is an innate immune molecule that prevents the bacterial infection.
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Affiliation(s)
- Lan-Lan Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China
| | - Jin Xie
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China
| | - Dong-Dong Cao
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China
| | - Ning Jia
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China
| | - Ya-Juan Li
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Hui Sun
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China
| | - Wei-Fang Li
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China
| | - Bing Hu
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China.
| | - Yuxing Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China.
| | - Cong-Zhao Zhou
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China; Key Laboratory of Structural Biology, Chinese Academy of Science, Hefei, Anhui 230027, China.
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26
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Fahie MA, Liang L, Avelino AR, Pham B, Limpikirati P, Vachet RW, Chen M. Disruption of the open conductance in the β-tongue mutants of Cytolysin A. Sci Rep 2018; 8:3796. [PMID: 29491391 PMCID: PMC5830503 DOI: 10.1038/s41598-018-22009-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/14/2018] [Indexed: 12/20/2022] Open
Abstract
Cytolysin A (ClyA) is a water-soluble alpha pore-forming toxin that assembles to form an oligomeric pore on host cell membranes. The ClyA monomer possesses an α-helical bundle with a β-sheet subdomain (the β-tongue) previously believed to be critical for pore assembly and/or insertion. Oligomerization of ClyA pores transforms the β-tongue into a helix-turn-helix that embeds into the lipid bilayer. Here, we show that mutations of the β-tongue did not prevent oligomerization or transmembrane insertion. Instead, β-tongue substitution mutants yielded pores with decreased conductance while a deletion mutation resulted in pores that rapidly closed following membrane association. Our results suggest that the β-tongue may play an essential structural role in stabilizing the open conformation of the transmembrane domain.
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Affiliation(s)
- Monifa A Fahie
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA, 01003, USA.,Department of Chemistry, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Lucas Liang
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Alzira R Avelino
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Bach Pham
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | | | - Richard W Vachet
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA, 01003, USA.,Department of Chemistry, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Min Chen
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA, 01003, USA. .,Department of Chemistry, University of Massachusetts Amherst, Amherst, MA, 01003, USA.
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Largo E, Gladue DP, Torralba J, Aguilella VM, Alcaraz A, Borca MV, Nieva JL. Mutation-induced changes of transmembrane pore size revealed by combined ion-channel conductance and single vesicle permeabilization analyses. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1015-1021. [PMID: 29317201 DOI: 10.1016/j.bbamem.2018.01.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/25/2017] [Accepted: 01/04/2018] [Indexed: 02/06/2023]
Abstract
Permeabilization of the Endoplasmic Reticulum (ER) is instrumental in the progression of host-cell infection by many viral pathogens. We have described that permeabilization of ER model membranes by the pore-forming domain of the Classical Swine Fever Virus (CSFV) p7 protein depends on two sequence determinants: the C-terminal transmembrane helix, and the preceding polar loop that regulates its activity. Here, by combining ion-channel activity measurements in planar lipid bilayers with imaging of single Giant Unilamellar Vesicles (GUVs), we demonstrate that point substitutions directed to conserved residues within these regions affect ER-like membrane permeabilization following distinct mechanisms. Whereas the polar loop appeared to be involved in protein insertion and oligomerization, substitution of residues predicted to face the lumen of the pore inhibited large conducting channels (>1 nS) over smaller ones (120 pS). Quantitative analyses of the ER-GUV distribution as a function of the solute size revealed a selective inhibition for the permeation of solutes with sizes larger than 4 kDa, further demonstrating that the mutation targeting the transmembrane helix prevented formation of the large pores. Collectively, our data support the idea that the pore-forming domain of p7 may assemble into finite pores with approximate diameters of 1 and 5 nm. Moreover, the observation that the mutation interfering with formation of the larger pores can hamper virus production without affecting ER localization or homo-oligomerization, suggests prospective strategies to block/attenuate pestiviruses.
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Affiliation(s)
- Eneko Largo
- Biofisika Institute (CSIC, UPV/EHU), Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain
| | - Douglas P Gladue
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Johana Torralba
- Biofisika Institute (CSIC, UPV/EHU), Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain
| | - Vicente M Aguilella
- Laboratory of Molecular Biophysics, Department of Physics, University Jaume I, 12071 Castellón, Spain
| | - Antonio Alcaraz
- Laboratory of Molecular Biophysics, Department of Physics, University Jaume I, 12071 Castellón, Spain
| | - Manuel V Borca
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - José L Nieva
- Biofisika Institute (CSIC, UPV/EHU), Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
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Mondal AK, Sreekumar A, Kundu N, Kathuria R, Verma P, Gandhi S, Chattopadhyay K. Structural Basis and Functional Implications of the Membrane Pore-Formation Mechanisms of Bacterial Pore-Forming Toxins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1112:281-291. [DOI: 10.1007/978-981-13-3065-0_19] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Pore-forming toxins in Cnidaria. Semin Cell Dev Biol 2017; 72:133-141. [DOI: 10.1016/j.semcdb.2017.07.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 07/14/2017] [Accepted: 07/20/2017] [Indexed: 01/05/2023]
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Jiang YY, Hou HT, Yang Q, Liu XC, He GW. Chloride Channels are Involved in the Development of Atrial Fibrillation - A Transcriptomic and proteomic Study. Sci Rep 2017; 7:10215. [PMID: 28860555 PMCID: PMC5579191 DOI: 10.1038/s41598-017-10590-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 08/11/2017] [Indexed: 11/23/2022] Open
Abstract
Electrical and structural remodeling processes are contributors to the self-perpetuating nature of atrial fibrillation (AF). However, their correlation has not been clarified. In this study, human atrial tissues from the patients with rheumatic mitral valve disease in either sinus rhythm or persistent AF were analyzed using a combined transcriptomic and proteomic approach. An up-regulation in chloride intracellular channel (CLIC) 1, 4, 5 and a rise in type IV collagen were revealed. Combined with the results from immunohistochemistry and electron microscope analysis, the distribution of type IV collagen and effects of fibrosis on myocyte membrane indicated the possible interaction between CLIC and type IV collagen, confirmed by protein structure prediction and co-immunoprecipitation. These results indicate that CLICs play an important role in the development of atrial fibrillation and that CLICs and structural type IV collagen may interact on each other to promote the development of AF in rheumatic mitral valve disease.
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Affiliation(s)
- Yi-Yao Jiang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, The Chinese Academy of Medical Sciences & Peking Union Medical College, & Nankai University, Tianjin, China.,The Affiliated Hospital of Hangzhou Normal University & Zhejiang University, Hangzhou, China
| | - Hai-Tao Hou
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, The Chinese Academy of Medical Sciences & Peking Union Medical College, & Nankai University, Tianjin, China
| | - Qin Yang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, The Chinese Academy of Medical Sciences & Peking Union Medical College, & Nankai University, Tianjin, China
| | - Xiao-Cheng Liu
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, The Chinese Academy of Medical Sciences & Peking Union Medical College, & Nankai University, Tianjin, China
| | - Guo-Wei He
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, The Chinese Academy of Medical Sciences & Peking Union Medical College, & Nankai University, Tianjin, China. .,The Affiliated Hospital of Hangzhou Normal University & Zhejiang University, Hangzhou, China. .,Department of Surgery, Oregon Health and Science University, Portland, Oregon, USA.
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31
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Desikan R, Patra SM, Sarthak K, Maiti PK, Ayappa KG. Comparison of coarse-grained (MARTINI) and atomistic molecular dynamics simulations of $$\alpha $$ α and $$\beta $$ β toxin nanopores in lipid membranes. J CHEM SCI 2017. [DOI: 10.1007/s12039-017-1316-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Sabareesan AT, Singh J, Roy S, Udgaonkar JB, Mathew MK. The Pathogenic A116V Mutation Enhances Ion-Selective Channel Formation by Prion Protein in Membranes. Biophys J 2017; 110:1766-1776. [PMID: 27119637 DOI: 10.1016/j.bpj.2016.03.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 02/23/2016] [Accepted: 03/07/2016] [Indexed: 11/19/2022] Open
Abstract
Prion diseases are a group of fatal neurodegenerative disorders that afflict mammals. Misfolded and aggregated forms of the prion protein (PrP(Sc)) have been associated with many prion diseases. A transmembrane form of PrP favored by the pathogenic mutation A116V is associated with Gerstmann-Sträussler-Scheinker syndrome, but no accumulation of PrP(Sc) is detected. However, the role of the transmembrane form of PrP in pathological processes leading to neuronal death remains unclear. This study reports that the full-length mouse PrP (moPrP) significantly increases the permeability of living cells to K(+), and forms K(+)- and Ca(2+)-selective channels in lipid membranes. Importantly, the pathogenic mutation A116V greatly increases the channel-forming capability of moPrP. The channels thus formed are impermeable to sodium and chloride ions, and are blocked by blockers of voltage-gated ion channels. Hydrogen-deuterium exchange studies coupled with mass spectrometry (HDX-MS) show that upon interaction with lipid, the central hydrophobic region (109-132) of the protein is protected against exchange, making it a good candidate for inserting into the membrane and lining the channel. HDX-MS also shows a dramatic increase in the protein-lipid stoichiometry for A116V moPrP, providing a rationale for its increased channel-forming capability. The results suggest that ion channel formation may be a possible mechanism of PrP-mediated neurodegeneration by the transmembrane forms of PrP.
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Affiliation(s)
- Ambadi Thody Sabareesan
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Jogender Singh
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Samrat Roy
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India; Biocon Bristol Myers Squibb Research Center, Bengaluru, India; School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT) University, Bhubaneswar, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India.
| | - M K Mathew
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India.
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Frangež R, Šuput D, Molgó J, Benoit E. Ostreolysin A/Pleurotolysin B and Equinatoxins: Structure, Function and Pathophysiological Effects of These Pore-Forming Proteins. Toxins (Basel) 2017; 9:toxins9040128. [PMID: 28379176 PMCID: PMC5408202 DOI: 10.3390/toxins9040128] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 03/30/2017] [Accepted: 03/31/2017] [Indexed: 12/17/2022] Open
Abstract
Acidic ostreolysin A/pleurotolysin B (OlyA/PlyB, formerly known as ostreolysin (Oly), and basic 20 kDa equinatoxins (EqTs) are cytolytic proteins isolated from the edible mushroom Pleurotus ostreatus and the sea anemone Actinia equina, respectively. Both toxins, although from different sources, share many similar biological activities: (i) colloid-osmotic shock by forming pores in cellular and artificial membranes enriched in cholesterol and sphingomyelin; (ii) increased vascular endothelial wall permeability in vivo and perivascular oedema; (iii) dose-dependent contraction of coronary vessels; (iv) haemolysis with pronounced hyperkalaemia in vivo; (v) bradycardia, myocardial ischemia and ventricular extrasystoles accompanied by progressive fall of arterial blood pressure and respiratory arrest in rodents. Both types of toxins are haemolytic within nanomolar range concentrations, and it seems that hyperkalaemia plays an important role in toxin cardiotoxicity. However, it was observed that the haemolytically more active EqT III is less toxic than EqT I, the most toxic and least haemolytic EqT. In mice, EqT II is more than 30 times more toxic than OlyA/PlyB when applied intravenously. These observations imply that haemolysis with hyperkalaemia is not the sole cause of the lethal activity of both toxins. Additional mechanisms responsible for lethal action of the two toxins are direct effects on heart, coronary vasoconstriction and related myocardial hypoxia. In this review, we appraise the pathophysiological mechanisms related to the chemical structure of OlyA/PlyB and EqTs, as well as their toxicity.
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Affiliation(s)
- Robert Frangež
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana; 1115-Ljubljana, Slovenia.
| | - Dušan Šuput
- Laboratory for Cell Physiology and Toxinology, Institute of Pathophysiology, School of Medicine, University of Ljubljana, P.O. Box 11, 1105-Ljubljana, Slovenia.
| | - Jordi Molgó
- DRF/Institut de Sciences de la Vie Frédéric Joliot/SIMOPRO, CEA de Saclay, and Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, 91190 Gif-sur-Yvette, France.
| | - Evelyne Benoit
- DRF/Institut de Sciences de la Vie Frédéric Joliot/SIMOPRO, CEA de Saclay, and Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, 91190 Gif-sur-Yvette, France.
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Mandal T, Kanchi S, Ayappa KG, Maiti PK. pH controlled gating of toxic protein pores by dendrimers. NANOSCALE 2016; 8:13045-13058. [PMID: 27328315 DOI: 10.1039/c6nr02963a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Designing effective nanoscale blockers for membrane inserted pores formed by pore forming toxins, which are expressed by several virulent bacterial strains, on a target cell membrane is a challenging and active area of research. Here we demonstrate that PAMAM dendrimers can act as effective pH controlled gating devices once the pore has been formed. We have used fully atomistic molecular dynamics (MD) simulations to characterize the cytolysin A (ClyA) protein pores modified with fifth generation (G5) PAMAM dendrimers. Our results show that the PAMAM dendrimer, in either its protonated (P) or non-protonated (NP) states can spontaneously enter the protein lumen. Protonated dendrimers interact strongly with the negatively charged protein pore lumen. As a consequence, P dendrimers assume a more expanded configuration efficiently blocking the pore when compared with the more compact configuration adopted by the neutral NP dendrimers creating a greater void space for the passage of water and ions. To quantify the effective blockage of the protein pore, we have calculated the pore conductance as well as the residence times by applying a weak force on the ions/water. Ionic currents are reduced by 91% for the P dendrimers and 31% for the NP dendrimers. The preferential binding of Cl(-) counter ions to the P dendrimer creates a zone of high Cl(-) concentration in the vicinity of the internalized dendrimer and a high concentration of K(+) ions in the transmembrane region of the pore lumen. In addition to steric effects, this induced charge segregation for the P dendrimer effectively blocks ionic transport through the pore. Our investigation shows that the bio-compatible PAMAM dendrimers can potentially be used to develop therapeutic protocols based on the pH sensitive gating of pores formed by pore forming toxins to mitigate bacterial infections.
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Affiliation(s)
- Taraknath Mandal
- Center for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India.
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Picaud F, Paris G, Gharbi T, Balme S, Lepoitevin M, Tangaraj V, Bechelany M, Janot JM, Balanzat E, Henn F. Biomimetic solution against dewetting in a highly hydrophobic nanopore. SOFT MATTER 2016; 12:4903-4911. [PMID: 27157717 DOI: 10.1039/c6sm00315j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A water molecule is the foundation of life and is the primary compound in every living system. While many of its properties are understood in a bulk solvent, its behavior in a small hydrophobic nanopore still raises fundamental questions. For instance, a wetting/dewetting transition in a hydrophobic solid-state or a polymer nanopore occurs stochastically and can only be prevented by external physical stimuli. Controlling these transitions would be a primary requirement to improve many applications. Some biological channels, such as gramicidin A (gA) proteins, show a high rate of water and ion diffusion in their central subnanochannel while their external surface is highly hydrophobic. The diameter of this channel is significantly smaller than the inner size of the lowest artificial nanopore in which water drying occurs (i.e. 1.4 nm). In this paper, we propose an innovative idea to generate nanopore wetting as a result of which the application of an external field is no longer required. In a nanopore, the drying or wetting of the inner walls occurs randomly (in experiments and in simulations). However, we have shown how the confinement of gA, in a dried hydrophobic nanopore, rapidly generates a stable wetting of the latter. We believe that this simple idea, based on biomimetism, could represent a real breakthrough that could help to improve and develop new nanoscale applications.
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Affiliation(s)
- Fabien Picaud
- Laboratoire de Nanomédecine, Imagerie et Thérapeutique, EA 4662, Université Bourgogne Franche-Comté, Centre Hospitalier Universitaire de Besançon, 16 route de Gray, 25030 Besançon cedex, France.
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36
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Zhang J, Yang Y, He W, Sun L. Necrosome core machinery: MLKL. Cell Mol Life Sci 2016; 73:2153-63. [PMID: 27048809 PMCID: PMC11108342 DOI: 10.1007/s00018-016-2190-5] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 03/18/2016] [Indexed: 12/22/2022]
Abstract
In the study of regulated cell death, the rapidly expanding field of regulated necrosis, in particular necroptosis, has been drawing much attention. The signaling of necroptosis represents a sophisticated form of a death pathway. Anti-caspase mechanisms (e.g., using inhibitors of caspases, or genetic ablation of caspase-8) switch cell fate from apoptosis to necroptosis. The initial extracellular death signals regulate RIP1 and RIP3 kinase activation. The RIP3-associated death complex assembly is necessary and sufficient to initiate necroptosis. MLKL was initially identified as an essential mediator of RIP1/RIP3 kinase-initiated necroptosis. Recent studies on the signal transduction using chemical tools and biomarkers support the idea that MLKL is able to make more functional sense for the core machinery of the necroptosis death complex, called the necrosome, to connect to the necroptosis execution. The experimental data available now have pointed that the activated MLKL forms membrane-disrupting pores causing membrane leakage, which extends the prototypical concept of morphological and biochemical events following necroptosis happening in vivo. The key role of MLKL in necroptosis signaling thus sheds light on the logic underlying this unique "membrane-explosive" cell death pathway. In this review, we provide the general concepts and strategies that underlie signal transduction of this form of cell death, and then focus specifically on the role of MLKL in necroptosis.
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Affiliation(s)
- Jing Zhang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Rd, Shanghai, 200031, China
| | - Yu Yang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Rd, Shanghai, 200031, China
| | - Wenyan He
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Rd, Shanghai, 200031, China
| | - Liming Sun
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Rd, Shanghai, 200031, China.
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Peroxisomal protein import pores. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:821-7. [DOI: 10.1016/j.bbamcr.2015.10.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/14/2015] [Accepted: 10/16/2015] [Indexed: 02/06/2023]
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38
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Rivera-de-Torre E, García-Linares S, Alegre-Cebollada J, Lacadena J, Gavilanes JG, Martínez-Del-Pozo Á. Synergistic Action of Actinoporin Isoforms from the Same Sea Anemone Species Assembled into Functionally Active Heteropores. J Biol Chem 2016; 291:14109-14119. [PMID: 27129251 DOI: 10.1074/jbc.m115.710491] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Indexed: 11/06/2022] Open
Abstract
Among the toxic polypeptides secreted in the venom of sea anemones, actinoporins are the pore-forming toxins whose toxic activity relies on the formation of oligomeric pores within biological membranes. Intriguingly, actinoporins appear as multigene families that give rise to many protein isoforms in the same individual displaying high sequence identities but large functional differences. However, the evolutionary advantage of producing such similar isotoxins is not fully understood. Here, using sticholysins I and II (StnI and StnII) from the sea anemone Stichodactyla helianthus, it is shown that actinoporin isoforms can potentiate each other's activity. Through hemolysis and calcein releasing assays, it is revealed that mixtures of StnI and StnII are more lytic than equivalent preparations of the corresponding isolated isoforms. It is then proposed that this synergy is due to the assembly of heteropores because (i) StnI and StnII can be chemically cross-linked at the membrane and (ii) the affinity of sticholysin mixtures for the membrane is increased with respect to any of them acting in isolation, as revealed by isothermal titration calorimetry experiments. These results help us understand the multigene nature of actinoporins and may be extended to other families of toxins that require oligomerization to exert toxicity.
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Affiliation(s)
- Esperanza Rivera-de-Torre
- Departamento de Bioquímica y Biología Molecular I, Facultades de Química y Biología, Universidad Complutense, 28040 Madrid
| | - Sara García-Linares
- Departamento de Bioquímica y Biología Molecular I, Facultades de Química y Biología, Universidad Complutense, 28040 Madrid
| | | | - Javier Lacadena
- Departamento de Bioquímica y Biología Molecular I, Facultades de Química y Biología, Universidad Complutense, 28040 Madrid
| | - José G Gavilanes
- Departamento de Bioquímica y Biología Molecular I, Facultades de Química y Biología, Universidad Complutense, 28040 Madrid.
| | - Álvaro Martínez-Del-Pozo
- Departamento de Bioquímica y Biología Molecular I, Facultades de Química y Biología, Universidad Complutense, 28040 Madrid.
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Peraro MD, van der Goot FG. Pore-forming toxins: ancient, but never really out of fashion. Nat Rev Microbiol 2015; 14:77-92. [DOI: 10.1038/nrmicro.2015.3] [Citation(s) in RCA: 476] [Impact Index Per Article: 52.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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40
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Reboul CF, Whisstock JC, Dunstone MA. Giant MACPF/CDC pore forming toxins: A class of their own. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:475-86. [PMID: 26607011 DOI: 10.1016/j.bbamem.2015.11.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 01/08/2023]
Abstract
Pore Forming Toxins (PFTs) represent a key mechanism for permitting the passage of proteins and small molecules across the lipid membrane. These proteins are typically produced as soluble monomers that self-assemble into ring-like oligomeric structures on the membrane surface. Following such assembly PFTs undergo a remarkable conformational change to insert into the lipid membrane. While many different protein families have independently evolved such ability, members of the Membrane Attack Complex PerForin/Cholesterol Dependent Cytolysin (MACPF/CDC) superfamily form distinctive giant β-barrel pores comprised of up to 50 monomers and up to 300Å in diameter. In this review we focus on recent advances in understanding the structure of these giant MACPF/CDC pores as well as the underlying molecular mechanisms leading to their formation. Commonalities and evolved variations of the pore forming mechanism across the superfamily are discussed. This article is part of a Special Issue entitled: Pore-Forming Toxins edited by Mauro Dalla Serra and Franco Gambale.
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Affiliation(s)
- Cyril F Reboul
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, Australia
| | - Michelle A Dunstone
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, Australia; Department of Microbiology, Monash University, Melbourne, Australia
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Pedrera L, Gomide AB, Sánchez RE, Ros U, Wilke N, Pazos F, Lanio ME, Itri R, Fanani ML, Alvarez C. The Presence of Sterols Favors Sticholysin I-Membrane Association and Pore Formation Regardless of Their Ability to Form Laterally Segregated Domains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:9911-9923. [PMID: 26273899 DOI: 10.1021/acs.langmuir.5b01687] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Sticholysin I (St I) is a pore-forming toxin (PFT) produced by the Caribbean Sea anemone Stichodactyla helianthus belonging to the actinoporin protein family, a unique class of eukaryotic PFT. As for actinoporins, it has been proposed that the presence of cholesterol (Chol) and the coexistence of lipid phases increase binding to the target membrane and pore-forming ability. However, little is known about the role of membrane structure and dynamics (phase state, fluidity, and the presence of lipid domains) on the activity of actinoporins or which regions of the membrane are the most favorable for protein insertion, oligomerization, and eventually pore formation. To gain insight into the role of membrane properties on the functional activity of St I, we studied its binding to monolayers and vesicles of phosphatidylcholine (PC), sphingomyelin (SM), and sterols inducing (ergosterol -Erg and cholesterol -Chol) or not (cholestenone - Cln) membrane phase segregation in liquid ordered (Lo) and liquid disordered (Ld) domains. This study revealed that St I binds and permeabilizes with higher efficiency sterol-containing membranes independently of their ability to form domains. We discuss the results in terms of the relevance of different membrane properties for the actinoporins mechanism of action, namely, molecular heterogeneity, specially potentiated in membranes with sterols inducers of phase separation (Chol or Erg) or Cln, a sterol noninducer of phase separation but with a high propensity to induce nonlamellar phase. The role of the Ld phase is pointed out as the most suitable platform for pore formation. In this regard, such regions in Chol-containing membranes seem to be the most favored due to its increased fluidity; this property promotes toxin insertion, diffusion, and oligomerization leading to pore formation.
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Affiliation(s)
- Lohans Pedrera
- Centro de Estudio de Proteínas (CEP), Facultad de Biología, Universidad de la Habana , CP 10400, La Habana, Cuba
| | - Andreza B Gomide
- Departamento de Física Aplicada, Instituto de Física, Universidade de São Paulo , 05508090, São Paulo, Brasil
- Centro Universitário Padre Anchieta, Jundiaí , 13207270, São Paulo, Brasil
| | - Rafael E Sánchez
- Centro de Estudio de Proteínas (CEP), Facultad de Biología, Universidad de la Habana , CP 10400, La Habana, Cuba
| | - Uris Ros
- Centro de Estudio de Proteínas (CEP), Facultad de Biología, Universidad de la Habana , CP 10400, La Habana, Cuba
| | - Natalia Wilke
- Departamento de Química Biológica, Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), Facultad de Ciencias Químicas-CONICET, Universidad Nacional de Córdoba , X5000HUA Córdoba, Argentina
| | - Fabiola Pazos
- Centro de Estudio de Proteínas (CEP), Facultad de Biología, Universidad de la Habana , CP 10400, La Habana, Cuba
| | - María E Lanio
- Centro de Estudio de Proteínas (CEP), Facultad de Biología, Universidad de la Habana , CP 10400, La Habana, Cuba
| | - Rosangela Itri
- Departamento de Física Aplicada, Instituto de Física, Universidade de São Paulo , 05508090, São Paulo, Brasil
| | - María Laura Fanani
- Departamento de Química Biológica, Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), Facultad de Ciencias Químicas-CONICET, Universidad Nacional de Córdoba , X5000HUA Córdoba, Argentina
| | - Carlos Alvarez
- Centro de Estudio de Proteínas (CEP), Facultad de Biología, Universidad de la Habana , CP 10400, La Habana, Cuba
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42
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Khilwani B, Chattopadhyay K. Signaling beyond Punching Holes: Modulation of Cellular Responses by Vibrio cholerae Cytolysin. Toxins (Basel) 2015; 7:3344-58. [PMID: 26308054 PMCID: PMC4549754 DOI: 10.3390/toxins7083344] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/12/2015] [Accepted: 08/14/2015] [Indexed: 01/20/2023] Open
Abstract
Pore-forming toxins (PFTs) are a distinct class of membrane-damaging cytolytic proteins that contribute significantly towards the virulence processes employed by various pathogenic bacteria. Vibrio cholerae cytolysin (VCC) is a prominent member of the beta-barrel PFT (beta-PFT) family. It is secreted by most of the pathogenic strains of the intestinal pathogen V. cholerae. Owing to its potent membrane-damaging cell-killing activity, VCC is believed to play critical roles in V. cholerae pathogenesis, particularly in those strains that lack the cholera toxin. Large numbers of studies have explored the mechanistic basis of the cell-killing activity of VCC. Consistent with the beta-PFT mode of action, VCC has been shown to act on the target cells by forming transmembrane oligomeric beta-barrel pores, thereby leading to permeabilization of the target cell membranes. Apart from the pore-formation-induced direct cell-killing action, VCC exhibits the potential to initiate a plethora of signal transduction pathways that may lead to apoptosis, or may act to enhance the cell survival/activation responses, depending on the type of target cells. In this review, we will present a concise view of our current understanding regarding the multiple aspects of these cellular responses, and their underlying signaling mechanisms, evoked by VCC.
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Affiliation(s)
- Barkha Khilwani
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences Indian Institute of Science Education and Research Mohali Sector 81, S. A. S. Nagar, Manauli PO 140306, Punjab, India.
| | - Kausik Chattopadhyay
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences Indian Institute of Science Education and Research Mohali Sector 81, S. A. S. Nagar, Manauli PO 140306, Punjab, India.
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43
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Ros U, García-Sáez AJ. More Than a Pore: The Interplay of Pore-Forming Proteins and Lipid Membranes. J Membr Biol 2015; 248:545-61. [PMID: 26087906 DOI: 10.1007/s00232-015-9820-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 06/12/2015] [Indexed: 01/09/2023]
Abstract
Pore-forming proteins (PFPs) punch holes in their target cell membrane to alter their permeability. Permeabilization of lipid membranes by PFPs has received special attention to study the basic molecular mechanisms of protein insertion into membranes and the development of biotechnological tools. PFPs act through a general multi-step mechanism that involves (i) membrane partitioning, (ii) insertion into the hydrophobic core of the bilayer, (iii) oligomerization, and (iv) pore formation. Interestingly, PFPs and membranes show a dynamic interplay. As PFPs are usually produced as soluble proteins, they require a large conformational change for membrane insertion. Moreover, membrane structure is modified upon PFPs insertion. In this context, the toroidal pore model has been proposed to describe a pore architecture in which not only protein molecules but also lipids are directly involved in the structure. Here, we discuss how PFPs and lipids cooperate and remodel each other to achieve pore formation, and explore new evidences of protein-lipid pore structures.
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Affiliation(s)
- Uris Ros
- Center for Protein Studies, Faculty of Biology, Calle 25 # 455, Plaza de la Revolución, Havana, Cuba
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44
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Leone P, Bebeacua C, Opota O, Kellenberger C, Klaholz B, Orlov I, Cambillau C, Lemaitre B, Roussel A. X-ray and Cryo-electron Microscopy Structures of Monalysin Pore-forming Toxin Reveal Multimerization of the Pro-form. J Biol Chem 2015; 290:13191-201. [PMID: 25847242 DOI: 10.1074/jbc.m115.646109] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Indexed: 11/06/2022] Open
Abstract
β-Barrel pore-forming toxins (β-PFT), a large family of bacterial toxins, are generally secreted as water-soluble monomers and can form oligomeric pores in membranes following proteolytic cleavage and interaction with cell surface receptors. Monalysin has been recently identified as a β-PFT that contributes to the virulence of Pseudomonas entomophila against Drosophila. It is secreted as a pro-protein that becomes active upon cleavage. Here we report the crystal and cryo-electron microscopy structure of the pro-form of Monalysin as well as the crystal structures of the cleaved form and of an inactive mutant lacking the membrane-spanning region. The overall structure of Monalysin displays an elongated shape, which resembles those of β-pore-forming toxins, such as Aerolysin, but is devoid of a receptor-binding domain. X-ray crystallography, cryo-electron microscopy, and light-scattering studies show that pro-Monalysin forms a stable doughnut-like 18-mer complex composed of two disk-shaped nonamers held together by N-terminal swapping of the pro-peptides. This observation is in contrast with the monomeric pro-form of the other β-PFTs that are receptor-dependent for membrane interaction. The membrane-spanning region of pro-Monalysin is fully buried in the center of the doughnut, suggesting that upon cleavage of pro-peptides, the two disk-shaped nonamers can, and have to, dissociate to leave the transmembrane segments free to deploy and lead to pore formation. In contrast with other toxins, the delivery of 18 subunits at once, nearby the cell surface, may be used to bypass the requirement of receptor-dependent concentration to reach the threshold for oligomerization into the pore-forming complex.
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Affiliation(s)
- Philippe Leone
- From the CNRS, Architecture et Fonction des Macromolécules Biologiques (AFMB), Unité Mixte de Recherche (UMR) 7257, 13288 Marseille, France, the Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, UMR 7257, 13288 Marseille, France
| | - Cecilia Bebeacua
- From the CNRS, Architecture et Fonction des Macromolécules Biologiques (AFMB), Unité Mixte de Recherche (UMR) 7257, 13288 Marseille, France, the Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, UMR 7257, 13288 Marseille, France
| | - Onya Opota
- the Global Health Institute, School of Life Sciences, École Polytechnique Fédérale Lausanne (EPFL), CH-1015 Lausanne, Switzerland, and
| | - Christine Kellenberger
- From the CNRS, Architecture et Fonction des Macromolécules Biologiques (AFMB), Unité Mixte de Recherche (UMR) 7257, 13288 Marseille, France, the Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, UMR 7257, 13288 Marseille, France
| | - Bruno Klaholz
- the Centre for Integrative Biology (CBI), Department of Integrated Structural Biology, IGBMC (Institute of Genetics and of Molecular and Cellular Biology), CNRS, UMR 7104/INSERM U964/Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Igor Orlov
- the Centre for Integrative Biology (CBI), Department of Integrated Structural Biology, IGBMC (Institute of Genetics and of Molecular and Cellular Biology), CNRS, UMR 7104/INSERM U964/Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Christian Cambillau
- From the CNRS, Architecture et Fonction des Macromolécules Biologiques (AFMB), Unité Mixte de Recherche (UMR) 7257, 13288 Marseille, France, the Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, UMR 7257, 13288 Marseille, France
| | - Bruno Lemaitre
- the Global Health Institute, School of Life Sciences, École Polytechnique Fédérale Lausanne (EPFL), CH-1015 Lausanne, Switzerland, and
| | - Alain Roussel
- From the CNRS, Architecture et Fonction des Macromolécules Biologiques (AFMB), Unité Mixte de Recherche (UMR) 7257, 13288 Marseille, France, the Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, UMR 7257, 13288 Marseille, France,
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45
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Roderer D, Benke S, Müller M, Fäh-Rechsteiner H, Ban N, Schuler B, Glockshuber R. Characterization of Variants of the Pore-Forming Toxin ClyA from Escherichia coli Controlled by a Redox Switch. Biochemistry 2014; 53:6357-69. [DOI: 10.1021/bi5007578] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel Roderer
- Institute
of Molecular Biology and Biophysics, ETH Zürich, Otto-Stern-Weg
5, CH-8093 Zürich, Switzerland
| | - Stephan Benke
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Marcus Müller
- Institute
of Molecular Biology and Biophysics, ETH Zürich, Otto-Stern-Weg
5, CH-8093 Zürich, Switzerland
| | - Helene Fäh-Rechsteiner
- Institute
of Molecular Biology and Biophysics, ETH Zürich, Otto-Stern-Weg
5, CH-8093 Zürich, Switzerland
| | - Nenad Ban
- Institute
of Molecular Biology and Biophysics, ETH Zürich, Otto-Stern-Weg
5, CH-8093 Zürich, Switzerland
| | - Benjamin Schuler
- Department
of Biochemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Rudi Glockshuber
- Institute
of Molecular Biology and Biophysics, ETH Zürich, Otto-Stern-Weg
5, CH-8093 Zürich, Switzerland
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46
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Molecular basis of transmembrane beta-barrel formation of staphylococcal pore-forming toxins. Nat Commun 2014; 5:4897. [DOI: 10.1038/ncomms5897] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 08/01/2014] [Indexed: 01/05/2023] Open
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Gurnev PA, Nestorovich EM. Channel-forming bacterial toxins in biosensing and macromolecule delivery. Toxins (Basel) 2014; 6:2483-540. [PMID: 25153255 PMCID: PMC4147595 DOI: 10.3390/toxins6082483] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 08/08/2014] [Accepted: 08/08/2014] [Indexed: 12/19/2022] Open
Abstract
To intoxicate cells, pore-forming bacterial toxins are evolved to allow for the transmembrane traffic of different substrates, ranging from small inorganic ions to cell-specific polypeptides. Recent developments in single-channel electrical recordings, X-ray crystallography, protein engineering, and computational methods have generated a large body of knowledge about the basic principles of channel-mediated molecular transport. These discoveries provide a robust framework for expansion of the described principles and methods toward use of biological nanopores in the growing field of nanobiotechnology. This article, written for a special volume on "Intracellular Traffic and Transport of Bacterial Protein Toxins", reviews the current state of applications of pore-forming bacterial toxins in small- and macromolecule-sensing, targeted cancer therapy, and drug delivery. We discuss the electrophysiological studies that explore molecular details of channel-facilitated protein and polymer transport across cellular membranes using both natural and foreign substrates. The review focuses on the structurally and functionally different bacterial toxins: gramicidin A of Bacillus brevis, α-hemolysin of Staphylococcus aureus, and binary toxin of Bacillus anthracis, which have found their "second life" in a variety of developing medical and technological applications.
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Affiliation(s)
- Philip A Gurnev
- Physics Department, University of Massachusetts, Amherst, MA 01003, USA.
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48
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Abstract
The cell membrane is crucial for protection of the cell from its environment. MACPF/CDC proteins are a large superfamily known to be essential for bacterial pathogenesis and proper functioning of the immune system. The three most studied groups of MACPF/CDC proteins are cholesterol-dependent cytolysins from bacteria, the membrane attack complex of complement and human perforin. Their primary function is to form transmembrane pores in target cell membranes. The common mechanism of action comprises water-soluble monomeric proteins binding to the host cell membrane, oligomerization, and formation of a functional pore. This causes a disturbance in gradients of ions and other molecules across the membrane and can lead to cell death. Cells react to this form of attack in a complex manner. Responses can be general, like removing the perforated part of the membrane, or more specific, in many cases depending on binding of proteins to specific receptors to trigger various signalling cascades.
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49
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Jiang L, Phang JM, Yu J, Harrop SJ, Sokolova AV, Duff AP, Wilk KE, Alkhamici H, Breit SN, Valenzuela SM, Brown LJ, Curmi PMG. CLIC proteins, ezrin, radixin, moesin and the coupling of membranes to the actin cytoskeleton: a smoking gun? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:643-57. [PMID: 23732235 DOI: 10.1016/j.bbamem.2013.05.025] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 05/20/2013] [Accepted: 05/21/2013] [Indexed: 12/20/2022]
Abstract
The CLIC proteins are a highly conserved family of metazoan proteins with the unusual ability to adopt both soluble and integral membrane forms. The physiological functions of CLIC proteins may include enzymatic activity in the soluble form and anion channel activity in the integral membrane form. CLIC proteins are associated with the ERM proteins: ezrin, radixin and moesin. ERM proteins act as cross-linkers between membranes and the cortical actin cytoskeleton. Both CLIC and ERM proteins are controlled by Rho family small GTPases. CLIC proteins, ERM and Rho GTPases act in a concerted manner to control active membrane processes including the maintenance of microvillar structures, phagocytosis and vesicle trafficking. All of these processes involve the interaction of membranes with the underlying cortical actin cytoskeleton. The relationships between Rho GTPases, CLIC proteins, ERM proteins and the membrane:actin cytoskeleton interface are reviewed. Speculative models are proposed involving the formation of localised multi-protein complexes on the membrane surface that assemble via multiple weak interactions. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé.
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Affiliation(s)
- Lele Jiang
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW 2010, Australia
| | - Juanita M Phang
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Jiang Yu
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Stephen J Harrop
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Anna V Sokolova
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia
| | - Anthony P Duff
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia
| | - Krystyna E Wilk
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Heba Alkhamici
- School of Medical and Molecular Biosciences, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Samuel N Breit
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW 2010, Australia
| | - Stella M Valenzuela
- School of Medical and Molecular Biosciences, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Louise J Brown
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Paul M G Curmi
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW 2010, Australia; School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia.
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50
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Role of pore-forming toxins in neonatal sepsis. Clin Dev Immunol 2013; 2013:608456. [PMID: 23710203 PMCID: PMC3655490 DOI: 10.1155/2013/608456] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 03/27/2013] [Indexed: 11/17/2022]
Abstract
Protein toxins are important virulence factors contributing to neonatal sepsis. The major pathogens of neonatal sepsis, group B Streptococci, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus, secrete toxins of different molecular nature, which are key for defining the disease. Amongst these toxins are pore-forming exotoxins that are expressed as soluble monomers prior to engagement of the target cell membrane with subsequent formation of an aqueous membrane pore. Membrane pore formation is not only a means for immediate lysis of the targeted cell but also a general mechanism that contributes to penetration of epithelial barriers and evasion of the immune system, thus creating survival niches for the pathogens. Pore-forming toxins, however, can also contribute to the induction of inflammation and hence to the manifestation of sepsis. Clearly, pore-forming toxins are not the sole factors that drive sepsis progression, but they often act in concert with other bacterial effectors, especially in the initial stages of neonatal sepsis manifestation.
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