Purification of Streptococcal Pyrogenic Exotoxin A

Group A streptococci secrete a variety of molecules, many of which are recognized as virulence factors important in the establishment of streptococcal infections. Among these extracellular products is streptococcal pyrogenic exotoxin A (SPE A, scarlet fever toxin A, erythrogenic toxin A) (1 ). Other SPEs include toxin serotypes B and C (1 ), streptococcal superantigen (SSA) (2 ), and SPE F (mitogenic factor) (3 ,4 ). Combinations of these toxins are believed to be important in streptococcal toxic shock syndrome. The latter two molecules will not be discussed in this chapter, but methods utilized to purify SPEs A-C also may be used to purify SSA and SPE F.