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9. Prophage exotoxins enhance colonization fitness in epidemic scarlet fever-causing Streptococcus pyogenes

Author

Brouwer, Stephan, Barnett, Timothy C., Ly, Diane, Kasper, Katherine J., De Oliveira, David M. P., Rivera-Hernandez, Tania, Cork, Amanda J., McIntyre, Liam, Jespersen, Magnus G., Richter, Johanna, Schulz, Benjamin L., Dougan, Gordon, Nizet, Victor, Yuen, Kwok-Yung, You, Yuanhai, McCormick, John K., Sanderson-Smith, Martina L., Davies, Mark R., and Walker, Mark J.

Published
2020
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17. The plasminogen-binding group A streptococcal M protein-related protein Prp binds plasminogen via arginine and histidine residues

Author

Sanderson-Smith, Martina L., Dowton, Mark, Ranson, Marie, and Walker, Mark J.

Subjects
Thrombolytic drugs -- Research, Arginine -- Research, Streptococcus pyogenes -- Genetic aspects, Streptococcus pyogenes -- Research, Binding proteins -- Research, Histidine -- Research, Biological sciences
Abstract

The migration of the human pathogen Streptococcus pyogenes (group A streptococcus) from localized to deep tissue sites may result in severe invasive disease, and sequestration of the host zymogen plasminogen appears crucial for virulence. Here, we describe a novel plasminogen-binding M protein, the plasminogen-binding group A streptococcal M protein (PAM)-related protein (Prp). Prp is phylogenetically distinct from previously described plasminogen-binding M proteins of group A, C, and G streptococci. While competition experiments indicate that Prp binds plasminogen with a lower affinity than PAM (50% effective concentration = 0.34 [micro]M), Prp nonetheless binds plasminogen with high affinity and at physiologically relevant concentrations of plasminogen ([K.sub.d] = 7.8 nM). Site-directed mutagenesis of the putative plasminogen binding site indicates that unlike the majority of plasminogen receptors, Prp does not interact with plasminogen exclusively via lysine residues. Mutagenesis to alanine of lysine residues [Lys.sup.96] and [Lys.sup.101] reduced but did not abrogate plasminogen binding by Prp. Plasminogen binding was abolished only with the additional mutagenesis of [Arg.sup.107] and [His.sup.108] to alanine. Furthermore, mutagenesis of [Arg.sup.107] and [His.sup.108] abolished plasminogen binding by Prp despite the presence of [Lys.sup.96] and [Lys.sup.101] in the binding site. Thus, binding to plasminogen via arginine and histidine residues appears to be a conserved mechanism among plasminogen-binding M proteins.

Published
2007

20. Prophage exotoxins enhance colonization fitness in epidemic scarlet fever-causing Streptococcus pyogenes

Author

Brouwer, Stephan, primary, Barnett, Timothy C., additional, Ly, Diane, additional, Kasper, Katherine J., additional, De Oliveira, David M.P., additional, Rivera-Hernandez, Tania, additional, Cork, Amanda J., additional, McIntyre, Liam, additional, Jespersen, Magnus G., additional, Richter, Johanna, additional, Schulz, Benjamin L., additional, Dougan, Gordon, additional, Nizet, Victor, additional, Yuen, Kwok-Yung, additional, You, Yuanhai, additional, McCormick, John K., additional, Sanderson-Smith, Martina L., additional, Davies, Mark R., additional, and Walker, Mark J., additional

Published
2020
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22. Human glycan expression patterns influence Group A streptococcal colonization of epithelial cells

Author

De Oliveira, David M. P., primary, Everest-Dass, Arun, additional, Hartley-Tassell, Lauren, additional, Day, Christopher J., additional, Indraratna, Anuk, additional, Brouwer, Stephan, additional, Cleary, Ailish, additional, Kautto, Liisa, additional, Gorman, Jody, additional, Packer, Nicolle H., additional, Jennings, Michael P., additional, Walker, Mark J., additional, and Sanderson-Smith, Martina L., additional

Published
2019
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23. Group A Streptococcus Modulates Host Inflammation by Manipulating Polymorphonuclear Leukocyte Cell Death Responses

Author

Tsatsaronis, James A., Ly, Diane, Pupovac, Aleta, Goldmann, Oliver, Rohde, Manfred, Taylor, Jude M., Walker, Mark J., Medina, Eva, and Sanderson-Smith, Martina L.

Abstract

Polymorphonuclear leukocyte (PMN) cell death strongly influences the resolution of inflammatory episodes, and may exacerbate adverse pathologies in response to infection. We investigated PMN cell death mechanisms following infection by virulent group A Streptococcus (GAS). Human PMNs were infected in vitro with a clinical, virulent GAS isolate and an avirulent derivative strain, and compared for phagocytosis, the production of reactive oxygen species (ROS), mitochondrial membrane depolarization and apoptotic markers. C57BL/6J mice were then infected, in order to observe the effects on murine PMNs in vivo. Human PMNs phagocytosed virulent GAS less efficiently, produced less ROS and underwent reduced mitochondrial membrane depolarization compared with phagocytosis of avirulent GAS. Morphological and biochemical analyses revealed that PMNs infected with avirulent GAS exhibited nuclear fragmentation and caspase-3 activation consistent with an anti-inflammatory apoptotic phenotype. Conversely, virulent GAS induced PMN vacuolization and plasma membrane permeabilization, leading to a necrotic form of cell death. Infection of the mice with virulent GAS engendered significantly higher systemic pro-inflammatory cytokine release and localized infiltration of murine PMNs, with cells associated with virulent GAS infection exhibiting reduced apoptotic potential. Avirulent GAS infection was associated with lower levels of proinflammatory cytokines and tissue PMN apoptosis. We propose that the differences in PMN cell death mechanisms influence the inflammatory responses to infection by GAS. © 2015 S. Karger AG, Basel

Published
2024
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25. Bacterial plasminogen receptors: mediators of a multifaceted relationship

Author

Sanderson-Smith, Martina L., De Oliveira, David M.P., Ranson, Marie, and McArthur, Jason D.

Subjects
Zymogens -- Physiological aspects -- Health aspects, Thrombolytic drugs -- Dosage and administration, Microbiological chemistry -- Research, Biotechnology industry, High technology industry
Abstract

Multiple species of bacteria are able to sequester the host zymogen plasminogen to the cell surface. Once localised to the bacterial surface, plasminogen can act as a cofactor in adhesion, or, following activation to plasmin, provide a source of potent proteolytic activity. Numerous bacterial plasminogen receptors have been identified, and the mechanisms by which they interact with plasminogen are diverse. Here we provide an overview of bacterial plasminogen receptors and discuss the diverse role bacterial plasminogen acquisition plays in the relationship between bacteria and the host., 1. Introduction Recruitment of plasminogen to the bacterial cell surface is emerging as a central theme in host/pathogen interactions. The glycoprotein plasminogen is found in plasma and extracellular fluids at [...]

Published
2012
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26. Validation of an automated colony counting system for group A Streptococcus Infectious Diseases

Author

Frost, Hannah R. C., Tsoi, Shu Ki, Baker, Ciara A, Laho, Delphine, Sanderson-Smith, Martina L, Steer, Andrew C, and Smeesters, Pierre

Subjects
Automated, Automation, Colony counting, Colony Count, Microbial -- methods, Streptococcus pyogenes -- growth & development -- isolation & purification, Group A Streptococcus, Temperature, Humans, Reproducibility of Results, Biological Assay, Sciences bio-médicales et agricoles, Biologie, TTC
Abstract

Background: The practice of counting bacterial colony forming units on agar plates has long been used as a method to estimate the concentration of live bacteria in culture. However, due to the laborious and potentially error prone nature of this measurement technique, an alternative method is desirable. Recent technologic advancements have facilitated the development of automated colony counting systems, which reduce errors introduced during the manual counting process and recording of information. An additional benefit is the significant reduction in time taken to analyse colony counting data. Whilst automated counting procedures have been validated for a number of microorganisms, the process has not been successful for all bacteria due to the requirement for a relatively high contrast between bacterial colonies and growth medium. The purpose of this study was to validate an automated counting system for use with group A Streptococcus (GAS). Results: Methods: Twenty-one different GAS strains, representative of major emm-types, were selected for assessment. In order to introduce the required contrast for automated counting, 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) dye was added to Todd-Hewitt broth with yeast extract (THY) agar. Growth on THY agar with TTC was compared with growth on blood agar and THY agar to ensure the dye was not detrimental to bacterial growth. Automated colony counts using a ProtoCOL 3 instrument were compared with manual counting to confirm accuracy over the stages of the growth cycle (latent, mid-log and stationary phases) and in a number of different assays. The average percentage differences between plating and counting methods were analysed using the Bland-Altman method. Conclusions: Results: A percentage difference of ±10 % was determined as the cut-off for a critical difference between plating and counting methods. All strains measured had an average difference of less than 10 % when plated on THY agar with TTC. This consistency was also observed over all phases of the growth cycle and when plated in blood following bactericidal assays. Agreement between these methods suggest the use of an automated colony counting technique for GAS will significantly reduce time spent counting bacteria to enable a more efficient and accurate measurement of bacteria concentration in culture., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2016

28. Blood Group Antigen Recognition via the Group A Streptococcal M Protein Mediates Host Colonization

Author

De Oliveira, David M. P., primary, Hartley-Tassell, Lauren, additional, Everest-Dass, Arun, additional, Day, Christopher J., additional, Dabbs, Rebecca A., additional, Ve, Thomas, additional, Kobe, Bostjan, additional, Nizet, Victor, additional, Packer, Nicolle H., additional, Walker, Mark J., additional, Jennings, Michael P., additional, and Sanderson-Smith, Martina L., additional

Published
2017
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34. Plasmin(ogen) Acquisition by Group A Streptococcus Protects against C3b-Mediated Neutrophil Killing

Author

Ly, Diane, primary, Taylor, Jude M., additional, Tsatsaronis, James A., additional, Monteleone, Mercedes M., additional, Skora, Amanda S., additional, Donald, Cortny A., additional, Maddocks, Tracy, additional, Nizet, Victor, additional, West, Nicholas P., additional, Ranson, Marie, additional, Walker, Mark J., additional, McArthur, Jason D., additional, and Sanderson-Smith, Martina L., additional

Published
2013
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36. Streptococcal collagen‐like protein A and general stress protein 24 are immunomodulating virulence factors of group A Streptococcus

Author

Tsatsaronis, James A., primary, Hollands, Andrew, additional, Cole, Jason N., additional, Maamary, Peter G., additional, Gillen, Christine M., additional, Ben Zakour, Nouri L., additional, Kotb, Malak, additional, Nizet, Victor, additional, Beatson, Scott A, additional, Walker, Mark J., additional, and Sanderson‐Smith, Martina L., additional

Published
2013
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37. Parameters Governing Invasive Disease Propensity of Non-M1 Serotype Group A Streptococci

Author

Maamary, Peter G., primary, Sanderson-Smith, Martina L., additional, Aziz, Ramy K., additional, Hollands, Andrew, additional, Cole, Jason N., additional, McKay, Fiona C., additional, McArthur, Jason D., additional, Kirk, Joshua K., additional, Cork, Amanda J., additional, Keefe, Rachael J., additional, Kansal, Rita G., additional, Sun, Hongmin, additional, Taylor, William L., additional, Chhatwal, Gursharan S., additional, Ginsburg, David, additional, Nizet, Victor, additional, Kotb, Malak, additional, and Walker, Mark J., additional

Published
2010
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38. Allelic variants of streptokinase fromStreptococcus pyogenesdisplay functional differences in plasminogen activation

Author

McArthur, Jason D., primary, McKay, Fiona C., additional, Ramachandran, Vidiya, additional, Shyam, Priya, additional, Cork, Amanda J., additional, Sanderson‐Smith, Martina L., additional, Cole, Jason N., additional, Ringdahl, Ulrika, additional, Sjöbring, Ulf, additional, Ranson, Marie, additional, and Walker, Mark J., additional

Published
2008
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40. Trigger for group A streptococcal M1T1 invasive disease

Author

Cole, Jason N., primary, Mcarthur, Jason D., additional, Mckay, Fiona C., additional, Sanderson-Smith, Martina L., additional, Cork, Amanda J., additional, Ranson, Marie, additional, Rohde, Manfred, additional, Itzek, Andreas, additional, Sun, Hongmin, additional, Ginsburg, David, additional, Kotb, Malak, additional, Nizet, Victor, additional, Chhatwal, G. S., additional, Walker, Mark J., additional, and Cole, Jason N., additional

Published
2006
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41. Plasminogen Binding by Group A Streptococcal Isolates from a Region of Hyperendemicity for Streptococcal Skin Infection and a High Incidence of Invasive Infection

Author

McKay, Fiona C., primary, McArthur, Jason D., additional, Sanderson-Smith, Martina L., additional, Gardam, Sandra, additional, Currie, Bart J., additional, Sriprakash, Kadaba S., additional, Fagan, Peter K., additional, Towers, Rebecca J., additional, Batzloff, Michael R., additional, Chhatwal, Gursharan S., additional, Ranson, Marie, additional, and Walker, Mark J., additional

Published
2004
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43. Allelic variants of streptokinase from Streptococcus pyogenes display functional differences in plasminogen activation.

Author

McArthur, Jason D., McKay, Fiona C., Ramachandran, Vidiya, Shyam, Priya, Cork, Amanda J., Sanderson-Smith, Martina L., Cole, Jason N., Ringdahl, Ulrika, Sjöbring, Ulf, Ranson, Marie, and Walker, Mark J.

Subjects
STREPTOKINASE, STREPTOCOCCUS pyogenes, PLASMINOGEN activators, FIBRINOGEN, MICROBIAL virulence
Abstract

A common mammalian defense mechanism employed to prevent systemic dissemination of invasive bacteria involves occlusion of local microvasculature and encapsulation of bacteria within fibrin networks. Acquisition of plasmin activity at the bacterial cell surface circumvents this defense mechanism, allowing invasive disease initiation. To facilitate this process, S. pyogenes secretes streptokinase, a plasminogen-activating protein. Streptokinase polymorphism exhibited by S. pyogenes isolates is well characterized. However, the functional differences displayed by these variants and the biological significance of this variation has not been elucidated. Phylogenetic analysis of ska sequences from 28 S. pyogenes isolates revealed 2 main sequence clusters (clusters 1 and 2). All strains secreted streptokinase, as determined by Western blotting, and were capable of acquiring cell surface plasmin activity after incubation in human plasma. Whereas culture supernatants from strains containing cluster 1 ska alleles also displayed soluble plasminogen activation activity, supernatants from strains containing cluster 2 ska alleles did not. Furthermore, plasminogen activation activity in culture supernatants from strains containing cluster 2 ska alleles could only be detected when plasminogen was prebound with fibrinogen. This study indicates that variant streptokinase proteins secreted by S. pyogenes isolates display differing plasminogen activation characteristics and may therefore play distinct roles in disease pathogenesis. [ABSTRACT FROM AUTHOR]

Published
2008
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44. The Maintenance of High Affinity Plasminogen Binding by Group A Streptococcal Plasminogen-binding M-Iike Protein Is Mediated by Arginine and Histidine Residues within the a1 and a2 Repeat Domains.

Author

Sanderson-Smith, Martina L., Walker, Mark J., and Ranson, Marie

Subjects
*PLASMINOGEN, *RADIOGENETICS, *FIBRINOLYTIC agents, *MUTAGENESIS, *GENETIC mutation, *BIOCHEMISTRY
Abstract

Subversion of the plasminogen activation system is implicated in the virulence of group A streptococci (GAS). GAS displays receptors for the human zymogen plasminogen on the cell surface, one of which is the plasminogen-binding group A streptococcal M-like protein (PAM). The plasminogen binding domain of PAM is highly variable, and this variation has been linked to host selective immune pressure. Site-directed mutagenesis of full-length PAM protein from an invasive GAS isolate was undertaken to assess the contribution of residues in the a1 and a2 repeat domains to plasminogen binding function. Mutagenesis to alanine of key plasminogen binding lysine residues in the a1 and a2 repeats (Lys98 and Lys111) did not abrogate plasminogen binding by PAM nor did additional mutagenesis of Arg101 and His102 and Glu104, which have previously been implicated in plasminogen binding. Plasminogen binding was only abolished with the additional mutagenesis of Arg114 and His115 to alanine. Furthermore, mutagenesis of both arginine (Arg101 and Arg114) and histidine (His102 and His115) residues abolished interaction with plasminogen despite the presence of Lys98 and Lys111 in the binding repeats. This study shows for the first time that residues Arg101, Arg114, His102, and His115 in both the a1 and a2 repeat domains of PAM can mediate high affinity plasminogen binding. These data suggest that highly conserved arginine and histidine residues may compensate for variation elsewhere in the a1 and a2 plasminogen binding repeats, and may explain the maintenance of high affinity plasminogen binding by naturally occurring variants of PAM. [ABSTRACT FROM AUTHOR]

Published
2006
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45. Plasmin(ogen) Acquisition by Group A StreptococcusProtects against C3b-Mediated Neutrophil Killing

Author

Ly, Diane, Taylor, Jude M., Tsatsaronis, James A., Monteleone, Mercedes M., Skora, Amanda S., Donald, Cortny A., Maddocks, Tracy, Nizet, Victor, West, Nicholas P., Ranson, Marie, Walker, Mark J., McArthur, Jason D., and Sanderson-Smith, Martina L.

Abstract

AbstractThe globally significant human pathogen group A Streptococcus(GAS) sequesters the host protease plasmin to the cell surface during invasive disease initiation. Recent evidence has shown that localized plasmin activity prevents opsonization of several bacterial species by key components of the innate immune system in vitro. Here we demonstrate that plasmin at the GAS cell surface resulted in degradation of complement factor C3b, and that plasminogen acquisition is associated with a decrease in C3b opsonization and neutrophil-mediated killing in vitro. Furthermore, the ability to acquire cell surface plasmin(ogen) correlates directly with a decrease in C3b opsonization, neutrophil phagocytosis, and increased bacterial survival in a humanized plasminogen mouse model of infection. These findings demonstrate that localized plasmin(ogen) plays an important role in facilitating GAS escape from the host innate immune response and increases bacterial virulence in the early stages of infection.Copyright © 2013 S. Karger AG, Basel

Published
2014
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46. Prophage exotoxins enhance colonization fitness in epidemic scarlet fever-causing Streptococcus pyogenes

Author

Tania Rivera-Hernandez, Yuanhai You, Diane Ly, Johanna Richter, Gordon Dougan, Timothy C. Barnett, Amanda J. Cork, Mark J. Walker, Katherine J. Kasper, Mark R. Davies, Magnus G. Jespersen, Martina L. Sanderson-Smith, Victor Nizet, Liam McIntyre, Kwok Yung Yuen, David M. P. De Oliveira, John K. McCormick, Stephan Brouwer, Benjamin L. Schulz, Barnett, Timothy C. [0000-0002-3346-5117], De Oliveira, David M. P. [0000-0002-5085-7163], Jespersen, Magnus G. [0000-0001-9751-9877], Nizet, Victor [0000-0003-3847-0422], Yuen, Kwok-Yung [0000-0002-2083-1552], McCormick, John K. [0000-0003-3742-7289], Sanderson-Smith, Martina L. [0000-0002-6366-4993], Davies, Mark R. [0000-0001-6141-5179], Walker, Mark J. [0000-0001-7423-2769], Apollo - University of Cambridge Repository, Barnett, Timothy C [0000-0002-3346-5117], De Oliveira, David MP [0000-0002-5085-7163], Jespersen, Magnus G [0000-0001-9751-9877], McCormick, John K [0000-0003-3742-7289], Sanderson-Smith, Martina L [0000-0002-6366-4993], Davies, Mark R [0000-0001-6141-5179], and Walker, Mark J [0000-0001-7423-2769]

Subjects
0301 basic medicine, Male, 82/29, Erythrocytes, 631/326/1320, Prophages, General Physics and Astronomy, medicine.disease_cause, Group A, 38/70, 13/1, 38/1, Superantigen, 38/22, lcsh:Science, Multidisciplinary, Superantigens, Streptococcus, article, Glutathione, Streptolysins, 38/77, Streptolysin, 38/39, Female, Infection, Scarlet Fever, Streptococcus pyogenes, Science, 030106 microbiology, Virulence, Exotoxins, 13/106, Mice, Transgenic, Biology, General Biochemistry, Genetics and Molecular Biology, Microbiology, 38/91, Cell Line, 82/80, 03 medical and health sciences, 14/34, Bacterial Proteins, medicine, Animals, Humans, 82/83, Prophage, 692/420/254, Bacteriology, General Chemistry, 64/110, biochemical phenomena, metabolism, and nutrition, medicine.disease, Mice, Inbred C57BL, 030104 developmental biology, 14/63, Mutation, Scarlet fever, bacteria, Pharynx, lcsh:Q
Abstract

The re-emergence of scarlet fever poses a new global public health threat. The capacity of North-East Asian serotype M12 (emm12) Streptococcus pyogenes (group A Streptococcus, GAS) to cause scarlet fever has been linked epidemiologically to the presence of novel prophages, including prophage ΦHKU.vir encoding the secreted superantigens SSA and SpeC and the DNase Spd1. Here, we report the molecular characterization of ΦHKU.vir-encoded exotoxins. We demonstrate that streptolysin O (SLO)-induced glutathione efflux from host cellular stores is a previously unappreciated GAS virulence mechanism that promotes SSA release and activity, representing the first description of a thiol-activated bacterial superantigen. Spd1 is required for resistance to neutrophil killing. Investigating single, double and triple isogenic knockout mutants of the ΦHKU.vir-encoded exotoxins, we find that SpeC and Spd1 act synergistically to facilitate nasopharyngeal colonization in a mouse model. These results offer insight into the pathogenesis of scarlet fever-causing GAS mediated by prophage ΦHKU.vir exotoxins., The pathogenesis of Streptococcus pyogenes (GAS) causing scarlet fever has been associated with the presence of prophages, such as ΦHKU.vir, and their products. Here, the authors characterize the exotoxins SpeC and Spd1 of ΦHKU.vir and show these to act synergistically to facilitate nasopharyngeal colonization in mice.

Published
2020
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47. Investigation of Group A Streptococcal Interactions with Host Glycan Structures Using High-Throughput Techniques: Glycan Microarray Analysis Using Recombinant Protein and Whole Cells.

Author

Indraratna A, De Oliveira DMP, Hartley-Tassell LE, Day CJ, Walker MJ, Jennings MP, and Sanderson-Smith ML

Subjects
Bacterial Adhesion physiology, Host-Pathogen Interactions physiology, Lectins metabolism, Microarray Analysis, High-Throughput Screening Assays methods, Polysaccharides metabolism, Streptococcus pyogenes metabolism
Abstract

Glycans, also known as carbohydrates, are abundant upon cell surfaces, where they often mediate host-pathogen interactions. The specific recognition of host glycans by pathogenic lectins is an important process that allows the adherence of bacteria to the host epithelial surface in many species, including Group A Streptococcus (GAS). Glycan microarrays present a sensitive, high-throughput approach for identifying novel lectin-glycan interactions and can be applied in the context of whole bacteria or purified bacterial proteins.

Published
2020
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