The nature of binding between the coenzyme and protein in transketolase from the swine liver

An analysis of a proteolytic hydrolysate of pig liver transketolase by thin-layer chromatography revealed the presence of a coenzyme-containing material which differed from free thiamine pyrophosphate in chromatographic behaviour. This coenzyme-containing material is distinct from the free coenzyme in terms of other properties as well, e.g., stability, pH dependence of thiochrome fluorescence, etc. It was demonstrated that incubation of enzyme preparations possessing a high specific activity (on the average, 2 E/mg) in acidic acetate buffer caused no or little detachment of the coenzyme, mainly in the composition of the heterogeneous material which, at least partly, was not represented by thiamine pyrophosphate.