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Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size
RTX (Repeats in ToXin) pore-forming toxins constitute an expanding family of exoproteins secreted by many Gram-negative bacteria and involved in infectious diseases caused by said pathogens. Despite the relevance in the host/pathogen interactions, the structure and characteristics of the lesions for...
Autores principales: | , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6572617/ https://www.ncbi.nlm.nih.gov/pubmed/31083482 http://dx.doi.org/10.3390/biom9050183 |
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author | González-Bullón, David B. Uribe, Kepa Largo, Eneko Guembelzu, Garazi García-Arribas, Aritz B. Martín, César Ostolaza, Helena |
author_facet | González-Bullón, David B. Uribe, Kepa Largo, Eneko Guembelzu, Garazi García-Arribas, Aritz B. Martín, César Ostolaza, Helena |
author_sort | González-Bullón, David |
collection | PubMed |
description | RTX (Repeats in ToXin) pore-forming toxins constitute an expanding family of exoproteins secreted by many Gram-negative bacteria and involved in infectious diseases caused by said pathogens. Despite the relevance in the host/pathogen interactions, the structure and characteristics of the lesions formed by these toxins remain enigmatic. Here, we capture the first direct nanoscale pictures of lytic pores formed by an RTX toxin, the Adenylate cyclase (ACT), secreted by the whooping cough bacterium Bordetella pertussis. We reveal that ACT associates into growing-size oligomers of variable stoichiometry and heterogeneous architecture (lines, arcs, and rings) that pierce the membrane, and that, depending on the incubation time and the toxin concentration, evolve into large enough “holes” so as to allow the flux of large molecular mass solutes, while vesicle integrity is preserved. We also resolve ACT assemblies of similar variable stoichiometry in the cell membrane of permeabilized target macrophages, proving that our model system recapitulates the process of ACT permeabilization in natural membranes. Based on our data we propose a non-concerted monomer insertion and sequential mechanism of toroidal pore formation by ACT. A size-tunable pore adds a new regulatory element to ACT-mediated cytotoxicity, with different pore sizes being putatively involved in different physiological scenarios or cell types. |
format | Online Article Text |
id | pubmed-6572617 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-65726172019-06-18 Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size González-Bullón, David B. Uribe, Kepa Largo, Eneko Guembelzu, Garazi García-Arribas, Aritz B. Martín, César Ostolaza, Helena Biomolecules Article RTX (Repeats in ToXin) pore-forming toxins constitute an expanding family of exoproteins secreted by many Gram-negative bacteria and involved in infectious diseases caused by said pathogens. Despite the relevance in the host/pathogen interactions, the structure and characteristics of the lesions formed by these toxins remain enigmatic. Here, we capture the first direct nanoscale pictures of lytic pores formed by an RTX toxin, the Adenylate cyclase (ACT), secreted by the whooping cough bacterium Bordetella pertussis. We reveal that ACT associates into growing-size oligomers of variable stoichiometry and heterogeneous architecture (lines, arcs, and rings) that pierce the membrane, and that, depending on the incubation time and the toxin concentration, evolve into large enough “holes” so as to allow the flux of large molecular mass solutes, while vesicle integrity is preserved. We also resolve ACT assemblies of similar variable stoichiometry in the cell membrane of permeabilized target macrophages, proving that our model system recapitulates the process of ACT permeabilization in natural membranes. Based on our data we propose a non-concerted monomer insertion and sequential mechanism of toroidal pore formation by ACT. A size-tunable pore adds a new regulatory element to ACT-mediated cytotoxicity, with different pore sizes being putatively involved in different physiological scenarios or cell types. MDPI 2019-05-10 /pmc/articles/PMC6572617/ /pubmed/31083482 http://dx.doi.org/10.3390/biom9050183 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article González-Bullón, David B. Uribe, Kepa Largo, Eneko Guembelzu, Garazi García-Arribas, Aritz B. Martín, César Ostolaza, Helena Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size |
title | Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size |
title_full | Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size |
title_fullStr | Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size |
title_full_unstemmed | Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size |
title_short | Membrane Permeabilization by Bordetella Adenylate Cyclase Toxin Involves Pores of Tunable Size |
title_sort | membrane permeabilization by bordetella adenylate cyclase toxin involves pores of tunable size |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6572617/ https://www.ncbi.nlm.nih.gov/pubmed/31083482 http://dx.doi.org/10.3390/biom9050183 |
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