Inhibition of streptococcal pyrogenic exotoxin B using allicin from garlic

2016 ◽  
Vol 93 ◽  
pp. 166-171 ◽  
Author(s):  
Mohsen Arzanlou
Keyword(s):  
Streptococcal Pyrogenic Exotoxin B

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

2005 ◽  
Vol 73 (2) ◽  
pp. 859-864 ◽  
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.

scholarly journals RNase Y-mediated regulation of the streptococcal pyrogenic exotoxin B

RNA Biology ◽  
2018 ◽  
Vol 15 (10) ◽  
pp. 1336-1347 ◽  
Author(s):  
Laura Broglia ◽  
Solange Materne ◽  
Anne-Laure Lécrivain ◽  
Karin Hahnke ◽  
Anaïs Le Rhun ◽  
...  
Keyword(s):  
Streptococcal Pyrogenic Exotoxin B ◽  
Rnase Y

scholarly journals Molecular mimicry between streptococcal pyrogenic exotoxin B and endothelial cells

2010 ◽  
Vol 90 (10) ◽  
pp. 1492-1506 ◽  
Author(s):  
Yueh-Hsia Luo ◽  
Woei-Jer Chuang ◽  
Jiunn-Jong Wu ◽  
Ming T Lin ◽  
Ching-Chuan Liu ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Molecular Mimicry ◽  
Streptococcal Pyrogenic Exotoxin B

Abrogation of streptococcal pyrogenic exotoxin B-mediated suppression of phagocytosis in U937 cells by Cordyceps sinensis mycelium via production of cytokines

2007 ◽  
Vol 45 (2) ◽  
pp. 278-285 ◽  
Author(s):  
Chih-Feng Kuo ◽  
Cheng-Chih Chen ◽  
Chiou-Feng Lin ◽  
Ming-Shiou Jan ◽  
Robert Y. Huang ◽  
...  
Keyword(s):  
Cordyceps Sinensis ◽  
U937 Cells ◽  
Streptococcal Pyrogenic Exotoxin B

scholarly journals Cysteine Protease Activity and Histamine Release from the Human Mast Cell Line HMC-1 Stimulated by Recombinant Streptococcal Pyrogenic Exotoxin B/Streptococcal Cysteine Protease

2002 ◽  
Vol 70 (7) ◽  
pp. 3944-3947 ◽  
Author(s):  
Yukino Watanabe ◽  
Yuko Todome ◽  
Hisashi Ohkuni ◽  
Shinsaku Sakurada ◽  
Toshio Ishikawa ◽  
...  
Keyword(s):  
Mast Cell ◽  
Histamine Release ◽  
Cell Line ◽  
Cysteine Protease ◽  
Protease Activity ◽  
Human Mast Cell ◽  
Streptococcal Toxic Shock Syndrome ◽  
Streptococcal Pyrogenic Exotoxin B ◽  
Mast Cell Line ◽  
Spe B

ABSTRACT We constructed the expression vector pSK-SCP containing the streptococcal exotoxin B gene (spe b) which expressed protease activity. We showed that the recombinant streptococcal pyogenic exotoxin B/streptococcal cysteine protease (rSPE B/SCP) was secreted into the culture supernatant of the transformant and retained its SCP activity, which was equivalent to or greater than that of the naturally occurring molecule. The secreted rSPE B/SCP induced histamine release and degranulation of the human mast cell line HMC-1. This study may contribute to the understanding of the pathogenic role of SPE B/SCP in streptococcal infection and streptococcal toxic shock syndrome.

Streptococcal pyrogenic exotoxin B cleaves properdin and inhibits complement-mediated opsonophagocytosis

2006 ◽  
Vol 339 (3) ◽  
pp. 779-784 ◽  
Author(s):  
Nina Tsao ◽  
Wan-Hua Tsai ◽  
Yee-Shin Lin ◽  
Woei-Jer Chuang ◽  
Chiou-Huey Wang ◽  
...  
Keyword(s):  
Streptococcal Pyrogenic Exotoxin B

scholarly journals Streptococcal Pyrogenic Exotoxin B-Induced Apoptosis in A549 Cells Is Mediated by a Receptor- and Mitochondrion-Dependent Pathway

2004 ◽  
Vol 72 (12) ◽  
pp. 7055-7062 ◽  
Author(s):  
Wan-Hua Tsai ◽  
Chia-Wen Chang ◽  
Woei-Jer Chuang ◽  
Yee-Shin Lin ◽  
Jiunn-Jong Wu ◽  
...  
Keyword(s):  
Protease Activity ◽  
Time Course ◽  
A549 Cells ◽  
Affinity Column ◽  
Dependent Manner ◽  
Apoptotic Pathway ◽  
Streptococcal Pyrogenic Exotoxin B ◽  
Induced Apoptosis ◽  
Dependent Pathway ◽  
Spe B

ABSTRACT It has been shown that streptococcal pyrogenic exotoxin B (SPE B) can induce cells to undergo apoptosis. The present study is to dissect the role of SPE B protease and SPE B protein in the apoptotic process of A549 cells and to elucidate the SPE B-induced apoptotic pathway. Recombinant SPE B (rSPE B) and C192S, a mutant of SPE B without protease activity, were expressed in Escherichia coli and purified by using an affinity column. The apoptosis of A549 cells was assayed by propidium iodide staining, followed by flow cytometry analysis. Our results showed that SPE B induced apoptosis in a dose-dependent manner, whereas C192S did not. When cells were pretreated with rSPE B (2 μg/ml) for as briefly as 5 min and then incubated with C192S of 28 kDa, an apoptosis that is proportional to the period of pretreatment was observed but not with C192S of 42 kDa. These results suggest that the extracellular protease activity of rSPE B is required for the initiation of apoptosis and that the size of SPE B is important for an effective induction of apoptosis. The time course analysis revealed that molecules activated in apoptosis were in the following order: caspase-8 (1.5 h), t-Bid (2.5 h), Bax (3 h), cytochrome c release (6 h), caspase-9 (7 h), and caspase-3 (8 h). The overexpression of Bcl-2 inhibited depolarization of mitochondrial membrane, cytochrome c release, and apoptosis. The results of the present study suggest that SPE B-induced apoptosis is mediated through a receptor-like mechanism and a mitochondrion-dependent pathway.

scholarly journals Streptococcal Pyrogenic Exotoxin B Enhances Tissue Damage Initiated by OtherStreptococcus pyogenesProducts

2001 ◽  
Vol 184 (6) ◽  
pp. 723-731 ◽  
Author(s):  
M. Saouda ◽  
W. Wu ◽  
P. Conran ◽  
M. D. P. Boyle
Keyword(s):  
Tissue Damage ◽  
Streptococcal Pyrogenic Exotoxin B

scholarly journals Identification and Characterization of Bicistronic speB and prsA Gene Expression in the Group A Streptococcus

2006 ◽  
Vol 188 (21) ◽  
pp. 7626-7634 ◽  
Author(s):  
Yongsheng Ma ◽  
Amy E. Bryant ◽  
Dan B. Salmi ◽  
Susan M. Hayes-Schroer ◽  
Eric McIndoo ◽  
...  
Keyword(s):  
Group A Streptococcus ◽  
Genetic Regulation ◽  
Active Form ◽  
Prolyl Isomerase ◽  
Peptidyl Prolyl Isomerase ◽  
Invasive Group ◽  
Genes Encoding ◽  
Group A ◽  
Streptococcal Pyrogenic Exotoxin B

ABSTRACT Severe, invasive group A streptococcal infections have reemerged worldwide, and extracellular toxins, including streptococcal pyrogenic exotoxin B (SpeB), have been implicated in pathogenesis. The genetic regulation of SpeB is not fully understood, and the mechanisms involved in the processing of the protoxin to its enzymatically active form have not been definitively established. The present work demonstrated that the genes encoding SpeB (speB) and a peptidyl-prolyl isomerase (prsA) constitute an operon with transcription initiated from two promoters upstream of speB. Further, the speB-prsA operon was transcribed as a bicistronic mRNA. This finding is in contrast to the generally accepted notion that speB is transcribed only as a monocistronic gene. In addition, prsA has its own promoter, and transcription from this promoter starts in early log phase, prior to the transcription of speB. Genomic disruption of prsA decreased the production of enzymatically active SpeB but not the level of the pro-SpeB zymogen. Taken together, these results demonstrate that prsA is required for production of fully mature, enzymatically active SpeB.

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