Comparative kinetics of the sulphatases A

The kinetic behaviour of the sulphatase A from kangaroo liver is that of a simple hysteretic system involving a substrate-modified form of the enzyme. The equilibrium between the native and substrate-modified forms is influenced by one of the reaction products, sulphate. The behaviour of the system differs markedly from that involving the ox enzyme and a generalised model is presented to account for the behaviour of the sulphatases A from ox, human, rat and kangaroo livers.