Is Staphylococcus a superantigen?
Staphylococcal enterotoxin B (SEB) of Staphylococcus aureus, and related superantigenic toxins produced by myriad microbes, are potent stimulators of the immune system causing a variety of human diseases from transient food poisoning to lethal toxic shock.
Does Staphylococcus aureus produce superantigen?
Superantigens (SAgs) are a family of potent immunostimulatory exotoxins known to be produced by only a few bacterial pathogens, including Staphylococcus aureus.
Does Streptococcus produce superantigen?
Group A streptococci can produce up to 11 serologically distinct superantigens (8, 15, 63–67).
Which Staphylococcus aureus toxin is a superantigen?
S. aureus produces a large variety of T-cell superantigens, including TSST-1 that induce toxic shock syndrome (TSS), SEs that are important causive toxins of food poisoning, and SEls that are not emetic in primate models.
Is enterotoxin A superantigen?
Staphylococcal enterotoxins (SEs) are broadly classified as superantigens, which, as described in detail below, have the ability to stimulate large populations of T cells (~20–30%) leading to the production of a cytokine bolus [23,24].
What are superantigen exotoxins?
As was learned earlier under Bacterial Pathogenicity, superantigens are type I toxins that can trigger a harmful immune response. Exotoxins are toxins, often proteins in nature, secreted from a living bacterium but also released upon bacterial lysis.
What is the superantigen produced by the Streptococcus pyogenes?
The globally prominent pathogen Streptococcus pyogenes secretes potent immunomodulatory proteins known as superantigens (SAgs), which engage lateral surfaces of major histocompatibility class II molecules and T-cell receptor (TCR) β-chain variable domains (Vβs).
What is superantigen exotoxin?
What is Staphylococcus aureus enterotoxin?
The S. aureus enterotoxins (SEs) are potent gastrointestinal exotoxins synthesized by S. aureus throughout the logarithmic phase of growth or during the transition from the exponential to the stationary phase [16,17,18,19,20].
How many enterotoxins are associated with Staphylococcus aureus?
Abstract. Staphylococcal enterotoxins (SEs) are produced by some Staphylococcus aureus strains contaminating foodstuffs and are the real causative agents of staphylococcal food poisoning. To date, 24 different SEs have been described, based on sequence homology but only a few of them have been fully characterized.
Which staphylococcal protein is superantigen?
The Superantigen Superfamily. The staphylococcal SAgs include the staphylococcal enterotoxins (SEs), the staphylococcal enterotoxin-like (SEls) proteins, and toxic shock syndrome toxin-1 (TSST-1) (Lina et al., 2004).