Role of Streptococcus pyogenes two-component response regulators in the temporal control of Mga and the Mga-regulated virulence gene emm.
نویسندگان
چکیده
We examined the role of Streptococcus pyogenes two-component response regulators (SptR) in expression of Mga and the Mga-regulated gene emm. Both serotype M6 and serotype M1 mutants in 12 of the 13 identified sptR genes exhibited levels of emm transcripts and Mga protein comparable to those of the wild type during exponential and stationary phases of growth. Thus, temporal control of these virulence genes does not require Spt response regulators.
منابع مشابه
Role of mga in growth phase regulation of virulence genes of the group A streptococcus.
To determine whether growth phase affects the expression of mga and other virulence-associated genes in the group A streptococcus (GAS), total RNA was isolated from the serotype M6 GAS strain JRS4 at different phases of growth and transcript levels were quantitated by hybridization with radiolabeled DNA probes. Expression of mga (which encodes a multiple gene regulator) and the Mga-regulated ge...
متن کاملRegulation of mga transcription in the group A streptococcus: specific binding of mga within its own promoter and evidence for a negative regulator.
Transcription of mga, encoding the multiple virulence gene regulator of the group A streptococcus, is positively autoregulated. This regulation requires a DNA region (Pmga) that contains both a promoter proximal to mga (P2) and a promoter located further upstream (P1). To determine if Mga has a direct role in this process, its ability to bind to specific sequences within Pmga was tested. A puri...
متن کاملTranscriptional activation of sclA by Mga requires a distal binding site in Streptococcus pyogenes.
Streptococcus pyogenes (the group A streptococcus [GAS]) is a medically significant pathogen of humans, causing a range of diseases from pharyngitis to necrotizing fasciitis. Several important GAS virulence genes are under the control of a pleiotropic regulator called Mga, or the multiple gene regulator of GAS, including the gene encoding the streptococcal collagen-like protein, or sclA. Analys...
متن کاملMga is sufficient to activate transcription in vitro of sof-sfbX and other Mga-regulated virulence genes in the group A Streptococcus.
The group A streptococcus (GAS), or Streptococcus pyogenes, is a strict human pathogen of medical significance, causing infections ranging from pharyngitis (strep throat) to necrotizing fasciitis (flesh-eating disease). Several virulence genes that encode factors important for colonization, internalization, and immune evasion are under the control of the multiple gene regulator of the GAS, or M...
متن کاملRestoration of Mga function to a Streptococcus pyogenes strain (M Type 50) that is virulent in mice.
The Mga protein in B514Sm, a Streptococcus pyogenes strain isolated as a mouse pathogen, contains amino acid substitutions at conserved sites that render the protein defective. Replacement of mga50 with the functional homolog mga4.1 restored full expression of Mga-regulated proteins. Restoration of Mga function did not affect fibrinogen binding, nor did it affect virulence in several mouse mode...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Infection and immunity
دوره 72 6 شماره
صفحات -
تاریخ انتشار 2004