Phenol Sulfotransferase (PST)

Phenol sulfotransferase, or PST (EC 2.8.2.1), catalyzes the sulfate conjugation of catecholamines and of phenolic drugs. PST is widely distributed in human and animal tissues that include the blood platelets. Human platelet PST exists in at least a thermolabile, or monoamine-metabolizing (SULT1A3, or STM), form and a thermostable, or phenol-metabolizing, form. Evidence that inheritance contributes to differences in levels of the 2 forms of the enzyme in whites was presented by Reveley et al. (1982), Price et al. (1988), and Van Loon and Weinshilboum (1984). Anderson and Jackson (1984) showed that the mean basal level of platelet thermostable PST activity in American blacks is significantly higher than the mean basal level in whites, whereas the average platelet thermolabile PST activity does not differ significantly in the 2 groups.