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Article ; Online: Pertussis toxin suppresses dendritic cell-mediated delivery of B. pertussis into lung-draining lymph nodes.

Nela Klimova / Jana Holubova / Gaia Streparola / Jakub Tomala / Ludmila Brazdilova / Ondrej Stanek / Ladislav Bumba / Peter Sebo

PLoS Pathogens, Vol 18, Iss 6, p e

2022 Volume 1010577

Abstract: The adenylate cyclase (ACT) and the pertussis (PT) toxins of Bordetella pertussis exert potent immunomodulatory activities that synergize to suppress host defense in the course of whooping cough pathogenesis. We compared the mouse lung infection ... ...

Abstract	The adenylate cyclase (ACT) and the pertussis (PT) toxins of Bordetella pertussis exert potent immunomodulatory activities that synergize to suppress host defense in the course of whooping cough pathogenesis. We compared the mouse lung infection capacities of B. pertussis (Bp) mutants (Bp AC- or Bp PT-) producing enzymatically inactive toxoids and confirm that ACT action is required for maximal bacterial proliferation in the first days of infection, whereas PT action is crucial for persistence of B. pertussis in mouse lungs. Despite accelerated and near complete clearance from the lungs by day 14 of infection, the PT- bacteria accumulated within the lymphoid tissue of lung-draining mediastinal lymph nodes (mLNs). In contrast, the wild type or AC- bacteria colonized the lungs but did not enter into mLNs. Lung infection by the PT- mutant triggered an early arrival of migratory conventional dendritic cells with associated bacteria into mLNs, where the PT- bacteria entered the T cell-rich paracortex of mLNs by day 5 and proliferated in clusters within the B-cell zone (cortex) of mLNs by day 14, being eventually phagocytosed by infiltrating neutrophils. Finally, only infection by the PT- bacteria triggered an early production of anti-B. pertussis serum IgG antibodies already within 14 days of infection. These results reveal that action of the pertussis toxin blocks DC-mediated delivery of B. pertussis bacteria into mLNs and prevents bacterial colonization of mLNs, thus hampering early adaptive immune response to B. pertussis infection.
Keywords	Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
Subject code	630
Language	English
Publishing date	2022-06-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Bordetella Pertussis Adenylate Cyclase Toxin Does Not Possess a Phospholipase A Activity; Serine 606 and Aspartate 1079 Residues Are Not Involved in Target Cell Delivery of the Adenylyl Cyclase Enzyme Domain

Ladislav Bumba / Jiri Masin / Adriana Osickova / Radim Osicka / Peter Sebo

Toxins, Vol 10, Iss 6, p

2018 Volume 245

Abstract: The adenylate cyclase toxin-hemolysin (CyaA, ACT, or AC-Hly) plays a crucial role in virulence and airway colonization capacity of the whooping cough agent Bordetella pertussis. The toxin penetrates target cell membranes and exhibits three distinct ... ...

Abstract	The adenylate cyclase toxin-hemolysin (CyaA, ACT, or AC-Hly) plays a crucial role in virulence and airway colonization capacity of the whooping cough agent Bordetella pertussis. The toxin penetrates target cell membranes and exhibits three distinct biological activities. A population of CyaA conformers forms small cation-selective pores that permeabilize the cell membrane for potassium efflux, which can provoke colloid-osmotic (oncotic) cell lysis. The other two activities are due to CyaA conformers that transiently form calcium influx conduits in the target cell membrane and translocate the adenylate cyclase (AC) enzyme into cytosol of cells. A fourth putative biological activity has recently been reported; an intrinsic phospholipase A (PLA) activity was claimed to be associated with the CyaA polypeptide and be involved in the mechanism of translocation of the AC enzyme polypeptide across cell membrane lipid bilayer. However, the conclusions drawn by the authors contradicted their own results and we show them to be erroneous. We demonstrate that highly purified CyaA is devoid of any detectable phospholipase A1 activity and that contrary to the published claims, the two putative conserved phospholipase A catalytic residues, namely the Ser606 and Asp1079 residues, are not involved in the process of membrane translocation of the AC domain of CyaA across target membranes.
Keywords	adenylate cyclase toxin ; phospholipase A activity ; AC domain translocation ; Medicine ; R
Subject code	571
Language	English
Publishing date	2018-06-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Acellular Pertussis Vaccine Inhibits Bordetella pertussis Clearance from the Nasal Mucosa of Mice

Jana Holubová / Ondřej Staněk / Ludmila Brázdilová / Jiří Mašín / Ladislav Bumba / Andrew R. Gorringe / Frances Alexander / Peter Šebo

Vaccines, Vol 8, Iss 695, p

2020 Volume 695

Abstract: Bordetella pertussis whole-cell vaccines (wP) caused a spectacular drop of global pertussis incidence, but since the replacement of wP with acellular pertussis vaccines (aP), pertussis has resurged in developed countries within 7 to 12 years of the ... ...

Abstract	Bordetella pertussis whole-cell vaccines (wP) caused a spectacular drop of global pertussis incidence, but since the replacement of wP with acellular pertussis vaccines (aP), pertussis has resurged in developed countries within 7 to 12 years of the change from wP to aP. In the mouse infection model, we examined whether addition of further protective antigens into the aP vaccine, such as type 2 and type 3 fimbriae (FIM2/3) with outer membrane lipooligosaccharide (LOS) and/or of the adenylate cyclase toxoid (dACT), which elicits antibodies neutralizing the CyaA toxin, could enhance the capacity of the aP vaccine to prevent colonization of the nasal mucosa by B. pertussis . The addition of the toxoid and of the opsonizing antibody-inducing agglutinogens modestly enhanced the already high capacity of intraperitoneally-administered aP vaccine to elicit sterilizing immunity, protecting mouse lungs from B. pertussis infection. At the same time, irrespective of FIM2/3 with LOS and dACT addition, the aP vaccination ablated the natural capacity of BALB/c mice to clear B. pertussis infection from the nasal cavity. While wP or sham-vaccinated animals cleared the nasal infection with similar kinetics within 7 weeks, administration of the aP vaccine promoted persistent colonization of mouse nasal mucosa by B. pertussis.
Keywords	Bordetella pertussis ; whooping cough ; vaccines ; nasal colonization ; Medicine ; R
Subject code	630
Language	English
Publishing date	2020-11-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Poly-N-Acetyllactosamine Neo-Glycoproteins as Nanomolar Ligands of Human Galectin-3

Ladislav Bumba / Dominic Laaf / Vojtěch Spiwok / Lothar Elling / Vladimír Křen / Pavla Bojarová

International Journal of Molecular Sciences, Vol 19, Iss 2, p

Binding Kinetics and Modeling

2018 Volume 372

Abstract: Galectin-3 (Gal-3) is recognized as a prognostic marker in several cancer types. Its involvement in tumor development and proliferation makes this lectin a promising target for early cancer diagnosis and anti-cancer therapies. Gal-3 recognizes poly-N- ... ...

Abstract	Galectin-3 (Gal-3) is recognized as a prognostic marker in several cancer types. Its involvement in tumor development and proliferation makes this lectin a promising target for early cancer diagnosis and anti-cancer therapies. Gal-3 recognizes poly-N-acetyllactosamine (LacNAc)-based carbohydrate motifs of glycoproteins and glycolipids with a high specificity for internal LacNAc epitopes. This study analyzes the mode and kinetics of binding of Gal-3 to a series of multivalent neo-glycoproteins presenting complex poly-LacNAc-based oligosaccharide ligands on a scaffold of bovine serum albumin. These neo-glycoproteins rank among the strongest Gal-3 ligands reported, with Kd reaching sub-nanomolar values as determined by surface plasmon resonance. Significant differences in the binding kinetics were observed within the ligand series, showing the tetrasaccharide capped with N,N′-diacetyllactosamine (LacdiNAc) as the strongest ligand of Gal-3 in this study. A molecular model of the Gal-3 carbohydrate recognition domain with docked oligosaccharide ligands is presented that shows the relations in the binding site at the molecular level. The neo-glycoproteins presented herein may be applied for selective recognition of Gal-3 both on the cell surface and in blood serum.
Keywords	carbohydrate ; galectin-3 ; galectins in diagnosis ; galectins in therapy ; glycosyltransferase ; surface plasmon resonance ; molecular modeling ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
Subject code	500
Language	English
Publishing date	2018-01-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Different roles of conserved tyrosine residues of the acylated domains in folding and activity of RTX toxins

Anna Lepesheva / Adriana Osickova / Jana Holubova / David Jurnecka / Sarka Knoblochova / Carlos Espinosa-Vinals / Ladislav Bumba / Karolina Skopova / Radovan Fiser / Radim Osicka / Peter Sebo / Jiri Masin

Scientific Reports, Vol 11, Iss 1, Pp 1-

2021 Volume 16

Abstract: Abstract Pore-forming repeats in toxins (RTX) are key virulence factors of many Gram-negative pathogens. We have recently shown that the aromatic side chain of the conserved tyrosine residue 940 within the acylated segment of the RTX adenylate cyclase ... ...

Abstract	Abstract Pore-forming repeats in toxins (RTX) are key virulence factors of many Gram-negative pathogens. We have recently shown that the aromatic side chain of the conserved tyrosine residue 940 within the acylated segment of the RTX adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) plays a key role in target cell membrane interaction of the toxin. Therefore, we used a truncated CyaA-derived RTX719 construct to analyze the impact of Y940 substitutions on functional folding of the acylated segment of CyaA. Size exclusion chromatography combined with CD spectroscopy revealed that replacement of the aromatic side chain of Y940 by the side chains of alanine or proline residues disrupted the calcium-dependent folding of RTX719 and led to self-aggregation of the otherwise soluble and monomeric protein. Intriguingly, corresponding alanine substitutions of the conserved Y642, Y643 and Y639 residues in the homologous RtxA, HlyA and ApxIA hemolysins from Kingella kingae, Escherichia coli and Actinobacillus pleuropneumoniae, affected the membrane insertion, pore-forming (hemolytic) and cytotoxic capacities of these toxins only marginally. Activities of these toxins were impaired only upon replacement of the conserved tyrosines by proline residues. It appears, hence, that the critical role of the aromatic side chain of the Y940 residue is highly specific for the functional folding of the acylated domain of CyaA and determines its capacity to penetrate target cell membrane.
Keywords	Medicine ; R ; Science ; Q
Subject code	572
Language	English
Publishing date	2021-10-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Production of Highly Active Recombinant Dermonecrotic Toxin of Bordetella Pertussis

Ondrej Stanek / Irena Linhartova / Jana Holubova / Ladislav Bumba / Zdenko Gardian / Anna Malandra / Barbora Bockova / Shihono Teruya / Yasuhiko Horiguchi / Radim Osicka / Peter Sebo

Toxins, Vol 12, Iss 596, p

2020 Volume 596

Abstract: Pathogenic Bordetella bacteria release a neurotropic dermonecrotic toxin (DNT) that is endocytosed into animal cells and permanently activates the Rho family GTPases by polyamination or deamidation of the glutamine residues in their switch II regions (e ... ...

Abstract	Pathogenic Bordetella bacteria release a neurotropic dermonecrotic toxin (DNT) that is endocytosed into animal cells and permanently activates the Rho family GTPases by polyamination or deamidation of the glutamine residues in their switch II regions (e.g., Gln63 of RhoA). DNT was found to enable high level colonization of the nasal cavity of pigs by B. bronchiseptica and the capacity of DNT to inhibit differentiation of nasal turbinate bone osteoblasts causes atrophic rhinitis in infected pigs. However, it remains unknown whether DNT plays any role also in virulence of the human pathogen B. pertussis and in pathogenesis of the whooping cough disease. We report a procedure for purification of large amounts of LPS-free recombinant DNT that exhibits a high biological activity on cells expressing the DNT receptors Cav3.1 and Cav3.2Electron microscopy and single particle image analysis of negatively stained preparations revealed that the DNT molecule adopts a V-shaped structure with well-resolved protein domains. These results open the way to structure–function studies on DNT and its interactions with airway epithelial layers.
Keywords	Bordetella ; GTPase ; deamidation ; dermonecrotic toxin ; recombinant ; electron microscopy ; negative staining ; image analysis ; Medicine ; R
Subject code	630
Language	English
Publishing date	2020-09-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Bordetella adenylate cyclase toxin is a unique ligand of the integrin complement receptor 3

Radim Osicka / Adriana Osickova / Shakir Hasan / Ladislav Bumba / Jiri Cerny / Peter Sebo

eLife, Vol

2015 Volume 4

Abstract: Integrins are heterodimeric cell surface adhesion and signaling receptors that are essential for metazoan existence. Some integrins contain an I-domain that is a major ligand binding site. The ligands preferentially engage the active forms of the ... ...

Abstract	Integrins are heterodimeric cell surface adhesion and signaling receptors that are essential for metazoan existence. Some integrins contain an I-domain that is a major ligand binding site. The ligands preferentially engage the active forms of the integrins and trigger signaling cascades that alter numerous cell functions. Here we found that the adenylate cyclase toxin (CyaA), a key virulence factor of the whooping cough agent Bordetella pertussis, preferentially binds an inactive form of the integrin complement receptor 3 (CR3), using a site outside of its I-domain. CyaA binding did not trigger downstream signaling of CR3 in human monocytes and CyaA-catalyzed elevation of cAMP effectively blocked CR3 signaling initiated by a natural ligand. This unprecedented type of integrin-ligand interaction distinguishes CyaA from all other known ligands of the I-domain-containing integrins and provides a mechanistic insight into the previously observed central role of CyaA in the pathogenesis of B. pertussis.
Keywords	adenylate cyclase toxin ; cAMP signaling ; complement receptor 3 ; Medicine ; R ; Science ; Q ; Biology (General) ; QH301-705.5
Subject code	500
Language	English
Publishing date	2015-12-01T00:00:00Z
Publisher	eLife Sciences Publications Ltd
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Bordetella adenylate cyclase toxin mobilizes its beta2 integrin receptor into lipid rafts to accomplish translocation across target cell membrane in two steps.

Ladislav Bumba / Jiri Masin / Radovan Fiser / Peter Sebo

PLoS Pathogens, Vol 6, Iss 5, p e

2010 Volume 1000901

Abstract: Bordetella adenylate cyclase toxin (CyaA) binds the alpha(M)beta(2) integrin (CD11b/CD18, Mac-1, or CR3) of myeloid phagocytes and delivers into their cytosol an adenylate cyclase (AC) enzyme that converts ATP into the key signaling molecule cAMP. We ... ...

Abstract	Bordetella adenylate cyclase toxin (CyaA) binds the alpha(M)beta(2) integrin (CD11b/CD18, Mac-1, or CR3) of myeloid phagocytes and delivers into their cytosol an adenylate cyclase (AC) enzyme that converts ATP into the key signaling molecule cAMP. We show that penetration of the AC domain across cell membrane proceeds in two steps. It starts by membrane insertion of a toxin 'translocation intermediate', which can be 'locked' in the membrane by the 3D1 antibody blocking AC domain translocation. Insertion of the 'intermediate' permeabilizes cells for influx of extracellular calcium ions and thus activates calpain-mediated cleavage of the talin tether. Recruitment of the integrin-CyaA complex into lipid rafts follows and the cholesterol-rich lipid environment promotes translocation of the AC domain across cell membrane. AC translocation into cells was inhibited upon raft disruption by cholesterol depletion, or when CyaA mobilization into rafts was blocked by inhibition of talin processing. Furthermore, CyaA mutants unable to mobilize calcium into cells failed to relocate into lipid rafts, and failed to translocate the AC domain across cell membrane, unless rescued by Ca(2+) influx promoted in trans by ionomycin or another CyaA protein. Hence, by mobilizing calcium ions into phagocytes, the 'translocation intermediate' promotes toxin piggybacking on integrin into lipid rafts and enables AC enzyme delivery into host cytosol.
Keywords	Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
Language	English
Publishing date	2010-05-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The conserved tyrosine residue 940 plays a key structural role in membrane interaction of Bordetella adenylate cyclase toxin

Jiri Masin / Jana Roderova / Adriana Osickova / Petr Novak / Ladislav Bumba / Radovan Fiser / Peter Sebo / Radim Osicka

Scientific Reports, Vol 7, Iss 1, Pp 1-

2017 Volume 14

Abstract: Abstract The adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) translocates its adenylate cyclase (AC) enzyme domain into target cells in a step that depends on membrane cholesterol content. We thus examined what role in toxin activities is played ... ...

Abstract	Abstract The adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) translocates its adenylate cyclase (AC) enzyme domain into target cells in a step that depends on membrane cholesterol content. We thus examined what role in toxin activities is played by the five putative cholesterol recognition amino acid consensus (CRAC) motifs predicted in CyaA hemolysin moiety. CRAC-disrupting phenylalanine substitutions had no impact on toxin activities and these were not inhibited by free cholesterol, showing that the putative CRAC motifs are not involved in cholesterol binding. However, helix-breaking proline substitutions in these segments uncovered a structural role of the Y632, Y658, Y725 and Y738 residues in AC domain delivery and pore formation by CyaA. Substitutions of Y940 of the fifth motif, conserved in the acylated domains of related RTX toxins, did not impact on fatty-acylation of CyaA by CyaC and the CyaA-Y940F mutant was intact for toxin activities on erythrocytes and myeloid cells. However, the Y940A or Y940P substitutions disrupted the capacity of CyaA to insert into artificial lipid bilayers or target cell membranes. The aromatic ring of tyrosine 940 side chain thus appears to play a key structural role in molecular interactions that initiate CyaA penetration into target membranes.
Keywords	Medicine ; R ; Science ; Q
Language	English
Publishing date	2017-08-01T00:00:00Z
Publisher	Nature Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Structure–Function Relationships Underlying the Capacity of Bordetella Adenylate Cyclase Toxin to Disarm Host Phagocytes

Jakub Novak / Ondrej Cerny / Adriana Osickova / Irena Linhartova / Jiri Masin / Ladislav Bumba / Peter Sebo / Radim Osicka

Toxins, Vol 9, Iss 10, p

2017 Volume 300

Abstract: Bordetellae, pathogenic to mammals, produce an immunomodulatory adenylate cyclase toxin–hemolysin (CyaA, ACT or AC-Hly) that enables them to overcome the innate immune defense of the host. CyaA subverts host phagocytic cells by an orchestrated action of ... ...

Abstract	Bordetellae, pathogenic to mammals, produce an immunomodulatory adenylate cyclase toxin–hemolysin (CyaA, ACT or AC-Hly) that enables them to overcome the innate immune defense of the host. CyaA subverts host phagocytic cells by an orchestrated action of its functional domains, where an extremely catalytically active adenylyl cyclase enzyme is delivered into phagocyte cytosol by a pore-forming repeat-in-toxin (RTX) cytolysin moiety. By targeting sentinel cells expressing the complement receptor 3, known as the CD11b/CD18 (αMβ2) integrin, CyaA compromises the bactericidal functions of host phagocytes and supports infection of host airways by Bordetellae. Here, we review the state of knowledge on structural and functional aspects of CyaA toxin action, placing particular emphasis on signaling mechanisms by which the toxin-produced 3′,5′-cyclic adenosine monophosphate (cAMP) subverts the physiology of phagocytic cells.
Keywords	adenylate cyclase toxin ; Bordetella ; β2 integrins ; cAMP ; CD11b/CD18 ; cell signaling ; complement receptor 3 ; innate immunity ; membrane pores ; repeats-in-toxin ; Medicine ; R
Language	English
Publishing date	2017-09-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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