Purification of exfoliation produced by Staphylococcus aureus of bacteriophage group 2 and its physicochemical properties

Abstract

Recently several groups of workers pointed out the close association between S. aureus of phage group 2 and the disease of infants known as toxic epidermal necrolysis of the Ritter's type. An experimental model with newborn mice for the study of the toxic epidermal necrolysis (TEN) is reported. Culture filtrate could cause a widespread exfoliation of the epidermis when injected subcutaneously or intraperitoneally into neonatal mice within 5 days of age. An extracellular product of staphylococcus responsible for the generalized exfoliation in neonatal mice is named 'exfoliatin'. An effective method for the isolation and purification of exfoliatin which has been recently reported by Melish and others as the staphylococcal toxin responsible for the scalded skin syndrome and the physicochemical properties of the purified toxin were described. From an active crude toxin produced by one of the clinical isolates of phage group 2, 4 types of toxic proteins which were all capable of causing the typical Nikolsky sign in neonatal mice were obtained and designated A, B, C, and D toxins. They had a molecular weight of about 24,000 and showed the same serological features in neutralization and precipitation tests, but were different from each other in showing a different single band with their respective mobilities in polyacrylamide disk electrophoresis. They were precipitated between pH 4.0 and 4.5 and lost their exfoliative capabilities. The resulting precipitates, however, could be solubilized in acetate buffer containing 0.5% sodium dodecyl sulfate, restoring their toxicities to almost the same extent as before. They were all stable when heated at 60°C for 60 min and at 100°C for 20 min, but lost their toxicities when heated at 100°C for 40 min. Additionally, the present authors observed that some staphylococcal strains not belonging to the typical phage group 2, isolated from patients with the scalded skin syndrome, were also capable of producing a similar but serologically unrelated exfoliative toxin.