title: Aryl sulfatase inactivation of slow reacting substance. Evidence for proteolysis as a major mechanism when ordinary commercial preparations of the enzyme are used.
abstract: Type II B arylsulfatases are known to inactivate slow reacting substance (SRS), but the mechanism is unclear. In the present study, ordinary commercial preparations of Sigma limpet arylsulfatase largely inactivated the glutathionyl and cysteinyl-glycyl forms of SRS, but the cysteinyl form of SRS was largely resistant to the enzyme. Evidence is presented which established that a major mechanism for the inactivation of the glutathionyl and cysteinyl-glycyl SRS types, at least by the particular enzyme preparations we have studied, involves cleavage of the glycine moiety from the sulfur containing side chain. This was confirmed by digestion studies with glutathione itself. In addition, there is some evidence to indicate that the enzyme may destabilize the double bond structure of the SRS molecule, contributing to the overall inactivation.
mesh_terms: D000818:Animals; D012898:Autacoids / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D002803:Chondro-4-Sulfatase / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D003545:Cysteine / Q000378:metabolism; D004151:Dipeptides / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D006168:Guinea Pigs; D009130:Muscle, Smooth / Q000187:drug effects; D051381:Rats; D013329:Structure-Activity Relationship; D013429:Sulfatases / Q000494:pharmacology*
chemical_list: D012898:Autacoids; D004151:Dipeptides; C028505:cysteinylglycine; D013429:Sulfatases; D002803:Chondro-4-Sulfatase; D005978:Glutathione; D003545:Cysteine; D005998:Glycine