Inactivation of Slow Reacting Substance of Anaphylaxis (SRS-A) by Arylsulfatases

Two different arylsulfatase preparations inactivated slow reacting substance of anaphylaxis (SRS-A) in a dose-related fashion. The loss of SRS-A activity could not be attributed to β-glucuronidase activity in the arylsulfatase preparations or to nonspecific adsorption to proteins. The arylsulfatase and SRS-A inactivating activities shared similar pH requirements, kinetics, and elution properties on Sephadex G-200 gel filtration. With spark source mass spectrometry, analysis of highly purified preparations of SRS-A revealed an abundance of 32S and 40Ca in the active samples as compared to controls. These findings indicate that SRS-A may contain a sulfate ester group.