... activation site (R144, N154, I152) and three in thesecond (F127, M436 and H428), and found that Ap4A and ADP interactwith the same site, but the sites for ATP and BPG remain uncertain. Thestructural ... cN-II, cN-III, cN-IA and cN-IB, and both cytosolic and mitochondrial 5¢(3¢)-deoxyribonu-cleotidases [5]. Even though all soluble 5 ¢-nucleotidasesshare the same reaction mechanism and possess con-served ... inosine and IMP remains unaltered, and the effect of theenzyme activators ATP and Mg2+is also unchanged(Table 1). Furthermore, by simultaneously measuringthe rate of nucleoside and phosphate...