... might be similar to that by which they inhibit the enzymatic activity of TGase Hydrolysing activity of GTP was also found in the purified PpTGase protein as in the case of TGase Mammalian TGase ... Next, GTP- hydrolysing activity of the purified PpTGase was investigated Mammalian TGase has both transamidating and GTP- hydrolysing activities, whereas TGase has no GTPase activity These proteins ... the TGase activity is regulated by the presence of GTP and Ca2+ Additionally, in order to confirm the specificity of the inhibition, other purine nucleotides (GTP, GDP, GMP, and ATP) were examined...