Sulfhydryl groups and transketolase activity

Abstract

Transketolase, an enzyme of pentose cycle, catalyzes the reaction of glycolaldehyde transport from the xylulose-5-phosphate to the ribose-5-phosphate with the formation of sedoheptulose-7-phosphate. There is not much known about this enzyme, especially in respect to its functional groups. In the previous work (Kochetov, Kobylyanskaya, being published) it was shown that one of the functional transketolase groups is imidazole group (or groups) of histidine, intactness of which is required for transketolase activity. In the present report data are presented indicating that a sulfhydryl group (or groups) is the other functional group of the enzyme. In this case silver ions served as a specific reagent for these groups.