Lung phenol sulfotransferases. Thermal stability of human and bovine enzymes.
Phenol sulfotransferase (PST) from human and bovine lung was purified about 1000-fold and the activity was measured with different acceptor substrates. Human lung PST catalyzes sulfation of both exo- and endogenous phenols, but the bovine lung enzyme only exogenous phenols. This difference in substrate specificity seems to be related to the presence of at least two different molecular forms of the enzyme: a thermostable and a thermolabile form in human lung, and two thermostable forms in bovine lung. Like the human platelet PST, the thermostable form from human lung is active with low concentrations of phenol (Km = 45 microM) and the thermolabile form with dopamine and high concentrations of phenol (Km = 909 microM). Bovine lung, which shows no catecholamine sulfating activity, contains two thermostable phenol sulfotransferases, both active with phenol but differing in their affinity to this substrate (Km = 40 microM and 335 microM, respectively).
Barańczyk-Kuźma
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A
Szymczyk
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T
D000328:Adult; D000818:Animals; D015239:Arylsulfotransferase; D002417:Cattle; D004298:Dopamine / Q000494:pharmacology; D006358:Hot Temperature; D006801:Humans; D007700:Kinetics; D008168:Lung / Q000201:enzymology*; D008875:Middle Aged; D019800:Phenol; D010636:Phenols / Q000494:pharmacology; D013379:Substrate Specificity; D013466:Sulfurtransferases / Q000032:analysis* / Q000302:isolation & purification
D010636:Phenols; D019800:Phenol; D013466:Sulfurtransferases; D015239:Arylsulfotransferase; D004298:Dopamine