Anionic forms of brain arylsulphatase B: evidence for a phosphorylated form in human and monkey

Abstract

Arylsulfatase A, B and an anionic form of B were separated by DEAE-cellulose column chromatography from the brains of man, monkey, rabbit, rat and chicken. The relative proportion of brain arylsulfatases differed from one species to the other. The anionic form of arylsulfatase B was a minor component as compared to arylsulfatase A or B in human and monkey brains while it was a major component in rat and chicken brains. Anionic arylsulfatase B was found in fetal human brains and in newborn monkey brain. In the rat brain, the activities of arylsulfatases A and anionic B showed an increasing trend during development, reaching a peak around 20 days after birth, without any change in their proportions. Treatment with Escherichia coli alkaline phosphatase resulted in the conversion of a major portion (about 70%) of the anionic arylsulfatase B of human and monkey brains into a less charged form which remained unbound to DEAE-cellulose. This conversion by phosphatase was inhibited by inorganic phosphate. Rat and chicken brain anionic arylsulfatase B was not susceptible to alkaline phosphatase. Vibrio cholerae neuraminidase treatment did not significantly affect the charge on anionic arylsulfatase B from any of the species. The results suggested a phosphorylated form of anionic arylsulfatase B exclusively in the primate brain.