Purification and characterization of thioltransferase (thiol: disulfide oxidoreductase) from rat liver cytosol : studies on its substrate specificity and possible biological role

Sammanfattning: This investigation describes an enzyme» from rat liver cytosol» catalyzing thiol-disulfide exchange reactions. The purification of the enzyme as well as many of its molecular characteristics are presented. Studies of the mechanism of action of the enzyme demonstrate that it should be considered as a thioltransferase although it can also be looked upon as a thiol:disulfide oxidoreductase. Careful investigations of the substrate specificity of thioltransferase have been performed. Thiols and disulfides of both high and Low molecular weight and of different purity were used as substrates. The conclusion of these investigations is that the enzyme has a broad substrate specificity. Possible biological roles for thioltransferase include regulation of the activities of other proteins by thiol-disulfide interchange reactions.