REGULATORY NETWORK IN STREPTOCOCCUS PYOGENES

Abstract

S. pyogenes or group A beta-haemolytic streptococcus (GAS) is an important human pathogen
that causes a wide variety of diseases, ranging from throat and skin infections, such as pharyngitis
and erysipelas, to severe invasive diseases, such as necrotizing fasciitis and streptococcal toxic
shock syndrome. S pyogenes produces a large number of secreted proteins and an array of matrixbinding proteins, that all contribute to virulence by mediating adhesion to host tissues, evasion of
host defense mechanisms, invasion, survival and tissue destruction. To establish a successful
infection, bacterial pathogens must precisely control expression of their virulence genes in response
to host signals. Virulence factor expression in GAS, like in other bacteria, is coordinately regulated
via “stand-alone” response regulators (RRs) and two-component signal transduction systems
(TCSs). In addition to these, three putative regulatory RNAs; fasXRNA, pelRNA and rivXRNA
have also been discovered. An increased understanding of the complex regulatory network involved
in the S pyogenes pathogenesis would help us in combating severe and invasive GAS diseases.