[The interaction of pyridoxamine-5'-thiophosphate with aspartate apo-transaminase].

Interaction of 5'-bromopyridoxamine with thiophosphate yeld 5'-phosphate thio ester of pyridoxamine (I). Apotransaminase and I reacted in equimolar amounts; a stable complex with 10--15 per cent of activity formed exhibiting a positive CD at 335 nm. Incubation of the complex with alpha-ketoglutarate led to formation of corresponding aldimine form and to partial splitting of the S--P bond. The same splitting take place during incubation of the I--apo-enzyme complex with substrate mixture.