Superantigen SpeA attenuates the biofilm forming capacity of Streptococcus pyogenes

The Role and Regulatory Network of the CiaRH Two-Component System in Streptococcal Species

“…Deletion of ciaR/H significantly decreased biofilm formation in vivo, which resulted in the inhibition of nasopharynx colonization by S. pneumoniae (Blanchette-Cain et al, 2013). In S. pyogenes, transcriptome analysis revealed that the superantigen SpeA suppresses biofilm formation, and this process is mediated by the CiaRH TCS (Babbar et al, 2019). Doubtlessly, inactivation of CiaRH can attenuate the biofilm-forming capacity in streptococci; therefore, targeting CiaRH may be an antibiofilm strategy for the development of antistreptococcal therapies.…”

“…Streptococcus pyogenes is an exclusive human pathogen that causes diseases ranging from pharyngitis, impetigo, abscesses, cellulitis, sepsis, necrotizing fasciitis, and streptococcal toxic shock syndrome to acute post-streptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease (Carapetis et al, 2005;Walker et al, 2014). In this bacterium, CiaRH was regulated by the CovRS TCS and was associated with virulence (Graham et al, 2002), and CiaRH sensed SpeA to modulate biofilm formation (Babbar et al, 2019;Figure 2C). In addition, a study conducted by Riani et al (2007) established transcriptome analyses between the wild-type strain and the ciaH mutant, which revealed that CiaH influences the transcription of 132 genes (63 genes were upregulated and 69 genes were downregulated in the ciaH mutant compared with the wild-type strain), including genes that encode divalent cation and other ion transporters, PTS systems, ribosomal proteins, virulence proteins, stress response proteins, and hypothetical and phage proteins (Figure 2C).…”

An Inventory of CiaR-Dependent Small Regulatory RNAs in Streptococci

“…In several species, CiaRH is involved in biofilm formation. In fact, the presence of SpeA (streptococcal pyogenic exotoxin A) in S. pyogenes leads to down-regulation of CiaRH expression genes and attenuates the biofilm-forming capacity, suggesting a link between TCS expression and biofilm formation ( Babbar et al, 2019 ). In S. sanguinis , the deletion of the ciaR gene up-regulates the expression of arginine biosynthesis genes resulting in the formation of a fragile biofilm ( Zhu et al, 2017 ).…”

Microbial biofilms and some aspects of anti-inflammatory drug use

“…One of such protection mechanisms is the formation of superantigens -a complex of bacterial structures directly recognized by T-lymphocytes and form the cell immune defense. As a result, the formation of the biofilm is inhibited [29].…”