Partial purification and properties of an enzyme from rat liver that catalyses the sulphation of l-tyrosyl derivatives

Abstract

1. An enzyme that catalyses the transfer of sulphate from adenosine 3'-phosphate 5'[(35)S]-sulphatophosphate to l-tyrosine methyl ester and tyramine was purified approx. 70-fold from female rat livers. 2. The partially purified preparation is still contaminated with adenosine 3'-phosphate 5'-sulphatophosphate-phenol sulphotransferase (EC 2.8.2.1), but a partial separation of the two enzymes can be achieved by chromatography on columns of Sephadex G-200 and DEAE-Sephadex. 3. The enzyme responsible for the sulphation of l-tyrosine methyl ester and tyramine is activated by dithiothreitol, 2-mercaptoethanol and GSH, the degree of activation being more marked with preparations previously stored at 0 or -10 degrees C. In contrast, the enzymic sulphation of p-nitrophenol is inhibited by all three thiols. Again, there is a quantitative difference in the degree of inhibition of the two enzymes by o-iodosobenzoate, p-chloromercuribenzoate, N-ethylmaleimide and iodoacetate. 4. Mixed-substrate experiments support the hypothesis that the enzyme responsible for the sulphation of l-tyrosine methyl ester and tyramine is separate from that responsible for the sulphation of p-nitrophenol. However, p-nitrophenol is a potent inhibitor of the sulphation of both tyrosyl derivatives whereas these latter compounds have no effect on the sulphation of p-nitrophenol.

Proceedings of the British Pharmacological Society

“…On enzymic hydrolysis, using either limpet arylsulphatase B or mylase (Koch Light), it was again totally hydrolysed liberating tyramine. Authentic tyramine-O-sulphate (Mattock & Jones, 1970) Klipstein (1964) reported that the highest incidence of subnormal serum folate concentrations occurred in epileptic patients who had been treated with phenytoin for long periods, but found no correlation between drug dose and the concentration of serum folate. The present experiment investigates the effect on concentrations of folate in serum and red cells of a short course of phenytoin in normal subjects.…”

Enzymic sulphation of p-nitrophenol and steroids by larval gut tissues of the southern armyworm (Prodenia eridania Cramer)

“…Although sulphate conjugates of phenol were first isolated and identified in mammals im the latter part ofthe last century, the mechanism ofthis reaction was not fully established until the discovery ofthe enzymic activation of sulphate and the isolation and identification of active sulphate, 3'-phosphoadenylyl sulphate (adenosine 3'-phosphate 5'-sulphatophosphate) some 15-20 years ago (Bernstein & McGilvery, 1952;DeMeio et al, 1953;Segal, 1955;DeMeio et al, 1955;Hilz & Lipmann, 1955;Robbins & Lipmann, 1956a,b, 1957. Studies on sulphate transfer from 3'phosphoadenylyl sulphate to various acceptors including mammalian hormonal steroids and L-tyrosine methyl ester have been actively pursued in the last few years. In mammals much of the recent emphasis on sulphoconjugation has been centred around the purification and characterization of the individual enzymes within the complex-forming family of sulphotransferases (Nose & Lipmann, 1958;Banerjee & Roy, 1966, 1968Hidaka et al, 1969;Mattock & Jones, 1970;McEvoy & Carroll, 1971). It now appears that in mammalian tissues there are at least four different sulphotransferases (Dodgson & Rose, 1970;Roy, 1970), which according to acceptor specificity are designated as phenol sulphotransferase (3'-phosphoadenylyl sulphate-phenol sulphotransferase, EC 2.8.2.1), 3fl-hydroxy steroid sulphotransferase (3'phosphoadenylyl sulphate-3p-hydroxy steroid sulphotransferase, EC 2.8.2.2), oestrone sulphotransferase (3'-phosphoadenylyl sulphate-oestrone sulphotransferase, EC 2.8.2.4) and L-tyrosine methyl ester sulphotransferase.…”

Purification from rat liver of an enzyme that catalyses the sulphurylation of phenols

“…This enzyme required added thiol for full activity and showed no requirement for magnesium ions. Mattock & Jones (1970) purified from female rat livers an enzyme that catalysed the sulphurylation of L-tyrosine methyl ester but this 70-fold purified preparation was contaminated with phenol sulphotransferase. The enzyme from rabbit liver which catalysed the sulphurylation of 5-hydroxytryptamine was purified 67-fold and this partially purified enzyme also catalysed the synthesis of p-nitrophenol sulphate (Hidaka, Nagatsu & Yagi, 1969).…”