Inverse Relation between Disease Severity and Expression of the Streptococcal Cysteine Protease, SpeB, among Clonal M1T1 Isolates Recovered from Invasive Group A Streptococcal Infection Cases

ABSTRACT The streptococcal cysteine protease (SpeB) is one of the major virulence factors produced by group A streptococci (GAS). In this study we investigated if differences exist in SpeB production by clonally related M1T1 clinical isolates derived from patients with invasive infections. Twenty-nine of these isolates were from nonsevere cases and 48 were from severe cases, including streptococcal toxic shock syndrome (STSS) and necrotizing fasciitis (NF) cases. The expression and amount of the 28-kDa SpeB protein produced were determined by quantitative Western blotting, and protease activity was measured by a fluorescent enzymatic assay. A high degree of variation in SpeB expression was seen among the isolates, and this variation seemed to correlate with the severity and/or clinical manifestation of the invasive infection. The mean amount of 28-kDa SpeB protein and cysteine protease activity produced by isolates from nonsevere cases was significantly higher than that from STSS cases (P = 0.001). This difference was partly due to the fact that 41% of STSS isolates produced little or no SpeB compared to only 14% of isolates recovered in nonsevere cases. Moreover, the cysteine protease activity among those isolates that expressed SpeB was significantly lower for STSS isolates than for isolates from nonsevere cases (P = 0.001). Increased SpeB production was also inversely correlated with intact M protein expression, and inhibition of cysteine protease activity blocked the cleavage of the surface M protein. Together, the data support the existence of both an “on-off” and a posttranslational regulatory mechanism(s) controlling SpeB production, and they suggest that isolates with the speB gene in the “off” state are more likely to spare the surface M protein and to be isolated from cases of severe rather than nonsevere invasive infection. These findings may have important implications for the role of SpeB in host-pathogen interactions via regulation of the expression of GAS virulence genes and the severity of invasive disease.

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The M Protein Is Dispensable for Maturation of Streptococcal Cysteine Protease SpeB

Infection and Immunity ◽

10.1128/iai.73.2.859-864.2005 ◽

2005 ◽

Vol 73 (2) ◽

pp. 859-864 ◽

Cited By ~ 9

Author(s):

Björn Zimmerlein ◽

Hae-Sun Park ◽

Shaoying Li ◽

Andreas Podbielski ◽

P. Patrick Cleary

Keyword(s):

Cysteine Protease ◽

Protease Activity ◽

Active Form ◽

Surface Protein ◽

M Protein ◽

Cysteine Protease Activity ◽

Group A ◽

Streptococcal Pyrogenic Exotoxin B ◽

Major Surface ◽

Culture Supernatants

ABSTRACT The streptococcal pyrogenic exotoxin B (SpeB) is an important virulence factor of group A streptococci (GAS) with cysteine protease activity. Maturation of SpeB to a proteolytically active form was suggested to be dependent on cell-wall-anchored M1 protein, the major surface protein of GAS (M. Collin and A. Olsén, Mol. Microbiol. 36:1306-1318, 2000). Collin and Olsén showed that mutant GAS strains expressing truncated M protein secrete a conformationally different form of unprocessed SpeB with no proteolytic activity. Alternatively, we hypothesized that a truncated M protein may interfere with processing of this secreted protease, and therefore we tested cysteine protease activity in genetically defined mutant strains that express either no M protein or membrane-anchored M protein with an in-frame deletion of the AB repeat region. Measurements of SpeB activity by cleavage of a substrate n-benzoyl-Pro-Phe-Arg-p-nitroanilide hydrochloride showed that the proteolytic activities in culture supernatants of both mutants were similar to those from the wild-type strain. In addition, Western blot analysis of culture supernatants showed that SpeB expression and processing to a mature form was unaffected by either deletion mutation. Therefore, we conclude that M protein is not required for maturation of the streptococcal cysteine protease SpeB.

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Risk Factors in the Pathogenesis of Invasive Group A Streptococcal Infections: Role of Protective Humoral Immunity

Infection and Immunity ◽

10.1128/iai.67.4.1871-1877.1999 ◽

1999 ◽

Vol 67 (4) ◽

pp. 1871-1877 ◽

Cited By ~ 88

Author(s):

Hesham Basma ◽

Anna Norrby-Teglund ◽

Yajaira Guedez ◽

Allison McGeer ◽

Donald E. Low ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Streptococcal Infection ◽

Host Susceptibility ◽

Streptococcal Toxic Shock Syndrome ◽

Invasive Infection ◽

Streptococcal Infections ◽

Invasive Group ◽

Invasive Infections ◽

Protective Antibodies ◽

Group A

ABSTRACT An impressive change in the epidemiology and severity of invasive group A streptococcal infections occurred in the 1980s, and the incidence of streptococcal toxic shock syndrome cases continues to rise. The reason for the resurgence of severe invasive cases remains a mystery—has there been a change in the pathogen or in host protective immunity? To address these questions, we have studied 33 patients with invasive infection caused by genotypically indistinguishable M1T1 strains of Streptococcus pyogenes who had different disease outcomes. Patients were classified as having severe (n= 21) and nonsevere (n = 12) invasive infections based on the presence or absence of shock and organ failure. Levels of anti-M1 bactericidal antibodies and of anti-streptococcal superantigen neutralizing antibodies in plasma were significantly lower in both groups than in age- and geographically matched healthy controls (P < 0.01). Importantly, the levels of these protective antibodies in plasma samples from severe and nonsevere invasive cases were not different. Together the data suggest that low levels of protective antibodies may contribute to host susceptibility to invasive streptococcal infection but do not modulate disease outcome. Other immunogenetic factors that regulate superantigen responses may influence the severity of systemic manifestations associated with invasive streptococcal infection.

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Development of a DNA aptamer that binds specifically to group A Streptococcus serotype M3

Canadian Journal of Microbiology ◽

10.1139/cjm-2016-0495 ◽

2017 ◽

Vol 63 (2) ◽

pp. 160-168 ◽

Cited By ~ 4

Author(s):

Hanif Alfavian ◽

Seyed Latif Mousavi Gargari ◽

Samaneh Rasoulinejad ◽

Arvin Medhat

Keyword(s):

Group A Streptococcus ◽

Dna Aptamer ◽

Live Cells ◽

Streptococcal Toxic Shock Syndrome ◽

Toxic Shock ◽

Apparent Dissociation Constant ◽

Invasive Infections ◽

Group A ◽

High Degree ◽

High Binding Affinity

Group A streptococcus (GAS) is an important Gram-positive pathogen that causes various human diseases ranging from peripheral lesions to invasive infections. The M protein is one of the main virulence factors present on the cell surface and is associated with invasive GAS infections. Compared with other M types, serotype M3 has a predominant role in lethal infections and demonstrates epidemic behaviors, including streptococcal toxic shock syndrome, bacteremia, and necrotizing fasciitis. Traditional methods for M typing are time-consuming, tedious, contradictory, and generally restricted to reference laboratories. Therefore, development of a new M-typing technique is needed. Aptamers with the ability to detect their target with a high degree of accuracy and specificity can be ideal candidates for specific M-typing of Streptococcus pyogenes. In this study DNA aptamers with a high binding affinity towards S. pyogenes serotype M3 were selected through 12 iterative rounds of the Systematic Evolution of Ligands by EXponential (SELEX) enrichment procedure using live cells as a target. We monitored the progress of the SELEX procedure by flow cytometry analysis. Of several aptamer sequences analyzed, 12L18A showed the highest binding efficiency towards S. pyogenes type M3, with an apparent dissociation constant (Kd) of 7.47 ± 1.72 pmol/L being the lowest. Therefore the isolated aptamer can be used in any tool, such as a biosensor, for the detection of S. pyogenes and can be used in the development of a novel M-typing system.

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Increased cysteine-protease activity in fecal supernatants from constipated IBS-C patients leads to occludin enzymatic degradation in colonic mucosa

Zeitschrift für Gastroenterologie ◽

10.1055/s-0031-1278504 ◽

2011 ◽

Vol 49 (05) ◽

Author(s):

R Róka ◽

A Annaházi ◽

V Bezirard ◽

H Eutamene ◽

L Ferrier ◽

...

Keyword(s):

Cysteine Protease ◽

Protease Activity ◽

Enzymatic Degradation ◽

Colonic Mucosa ◽

Cysteine Protease Activity

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Fecal supernatants from constipated IBS patients increase colonic permeability in mice by occludin degradation linked to cysteine-protease activity

Zeitschrift für Gastroenterologie ◽

10.1055/s-0031-1278432 ◽

2011 ◽

Vol 49 (05) ◽

Author(s):

A Annaházi ◽

R Róka ◽

M Leveque ◽

H Eutamene ◽

L Ferrier ◽

...

Keyword(s):

Cysteine Protease ◽

Protease Activity ◽

Cysteine Protease Activity

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855. Significance of Invasive Infections due to Methicillin Sensitive Staphylococcus aureus in the neonatal population

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1044 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S468-S468

Author(s):

Mariawy Riollano ◽

Deena Altman ◽

shanna kowalsky ◽

Stephanie Pan

Keyword(s):

Staphylococcus Aureus ◽

Clinical Characteristics ◽

Invasive Disease ◽

Control Measures ◽

Invasive Infection ◽

Single Center ◽

Infection Control Measures ◽

Invasive Infections ◽

Mrsa Colonization ◽

Neonatal Population

Abstract Background Staphylococcus aureus is a well-known cause of hospital acquired infections. Methicillin resistant staphylococcus aureus (MRSA) colonization is a recognized risk factor for invasive infections. The neonatal population in the intensive care unit (NICU) is particularly vulnerable to these types of infections, resulting in high mortality and morbidity. However, only scant data is available to establish the risk for invasive disease in patients with Methicillin sensitive staphylococcus aureus (MSSA). As a result, surveillance and prevention strategies are only address for MRSA colonization. Here, we describe the clinical characteristics of S. aureus colonized patients identified in late 2018 during transmission events in a single center NICU. As a result of the targeted surveillance investigation for MRSA infection control measures, S. aureus colonization was stratified, and we were able to compare the differences in invasive disease between MRSA and MSSA. Methods This is a retrospective chart review of the 47 colonized patients identified during October 2018- January 2019 SA transmission events in single center NICU. Risk factors, clinical characteristics, and the hospital course of these cases, including the proportion of invasive illness were reviewed. Results We found that most clinical characteristic, risk factors, and hospital course were the same between MRSA and MSSA colonized infants (p values > 0.05). Additionally, there was no difference in the proportion of invasive infection between MRSA and MSSA colonized patients (p value > 0.05). The type of invasive infections identified were SSTI, bacteremia, and osteomyelitis. Conclusion The proportion of invasive infection was the same in MSSA and MRSA colonized patients. This data provides us with supportive material for future recommendations of infection control measures for MSSA colonized patients. Disclosures All Authors: No reported disclosures

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