Enterotoxin Type B from Staphylococcus aureus

Enterotoxin B (SEB) is an extracellular toxin produced by certain strains of Staphylococcus aureus. SEB is synthesized as a precursor protein of 266 amino acids. This precursor is then activated during excretion of the protein by cleavage of an N-terminal portion of the molecule. The active enterotoxin B is a single 239 amino acid chain of molecular weight 28 kDa and isoelectric point of 8.

Staphylococcus aureus enterotoxins are responsible for many cases of food poisoning and toxic shock syndrome and have been implicated in rheumatoid arthritis, an autoimmune disease. SEB is a “superantigen” that binds to major histocompatibility complex (MHC) class II molecules. This activity elicits cytokine gene expression, phospholipase C activation, T-cell stimulation and serotonin release from mast cells from the host immune system. Enterotoxin B is also a strong mitogen, inducing DNA and interferon synthesis in lymphocytes.

SEB is a useful reagent for the production of cytokines in animals and cell culture. We are learning that cytokine production is of great importance in the progression of certain disease. Models of cytokine production in cells and animals serve to identify therapies which may control this aspect of infection.

SEB preparations from List Labs are highly purified by ion exchange chromatography from Staphylococcus aureus strain S6.

• Product #122 Enterotoxin Type B from S. aureus is provided lyophilized in a sodium phosphate buffer. This product is a select agent. Special restrictions apply.

Enterotoxin Type B Toxoid from Staphylococcus aureus

Enterotoxin Type B Toxoid from Staphylococcus aureus (SEB Toxoid) is produced from purified SEB which has been inactivated with formaldehyde. SEB Toxoid has been used to vaccinate monkeys by aerosol immunization.

• Product #123 Enterotoxin Type B Toxoid from S. aureus is provided lyophilized in a histidine buffer. All lots are tested to show no mitogenicity and minimal antigenicity. Details are provided on a C of A provided with each shipment.