3'-Phosphoadenylylsulfate:N-desulfoheparin sulfotransferase associated with a postmicrosomal particulate mastocytoma fraction

Abstract

An enzyme catalyzing the transfer of sulfate from 3'-phosphoadenylylsulfate to N-desulfoheparin was purified about 27-fold from Furth mouse mast cell tumor. The enzyme activity was associated with a "postmicrosomal" particulate fraction. A significant transfer of sulfate was observed primarily to the amino groups of N-desulfoheparin. The rate of the reaction was highest between pH 6.7 and 7.2, and it was strongly influenced by the ionic strength and nature of the buffer medium. The sulfate transfer was accelerated by Mg⁺⁺ but inhibited by p-chloromercuribenzoate, phenylmercuric acetate, and Cu⁺⁺ and Zn⁺⁺. The enzyme catalyzed also sulfation of heparan sulfate, and, to a much more limited extent, of chondroitin 4-sulfate and dermatansulfate; but heparin and p-nitrophenol were practically inactive as sulfate acceptors. The sulfotransferase preparation contained some 3'-phosphoadenylylsulfate sulfohydrolase, but it was essentially free of sulfate activating enzymes.