Enzymatic Transfer of Sulfate from 3 ’ - Phosphoadenosine S - Phosphosulfate to Uridine Diphosphate

The enzymes catalyzing the sulfation by 3’-phosphoadenosine 5’-phosphosulfate of chondroitin, chondroitin sulfates A, B, and C, and heparitin sulfate have been reported by Suzuki and Strominger (1) and Suzuki, Threnn, and Strominger (2) to occur in the isthmus region of hen oviduct’. The enzyme preparations used in these studies showed an absolute dependence on addition of the mucopolysaccharides as sulfate acceptor, since in the absence of added acceptor, no radioactive mucopolysaccharide was formed from a5S-PAPS.l Under this condition, however, at least eight unidentified products were formed and separated from each other by paper chromatography in an appropriate solvent. With addition of boiled enzyme, formation of the radioactive products was largely stimulated, suggesting the occurrence of endogenous acceptors in the enzyme preparation. Recent work done in this laboratory has shown that one of the acceptors is uridine diphosphate N-acetylgalactosamine 4-sulfate (UDP-GalNAc-4-sulfate), previously found by Strominger (3) in a homogenate of whole oviduct. Following these observations, the product2 of the UDP-GalNAc-4-sulfate-dependent reaction has been identified as UDP-N-acetylgalactosamine 4,6-disulfate (UDP-GalNAc-disulfate). Furthermore, a preliminary survey of the sulfate transfer activity has indicated that the soluble extract of albumen-secreting region (synonym: magnum) tends to be much richer in content than the preparations from the isthmus with respect to this enzyme. The purpose of this communication is to describe a partial purification of the enzyme from the albumen-secreting region, some of its properties,