Lougovoi C P, Kyriakidis D A
Laboratory of Biochemistry, Faculty of Chemistry, Aristotelian University of Thessaloniki, Greece.
Biochem Int. 1988 Feb;16(2):209-17.
Ornithine decarboxylase (ODC) of Tetrahymena pyriformis is inactivated by E. coli or calf intestinal alkaline phosphatase. Inactivated ODC by E. coli alkaline phosphatase, form b, can be allosterically reactivated to form a by purine-nucleosides or -nucleotides at 10(-4) M concentration. Inactivated ODC by calf intestinal alkaline phosphatase bound to agarose can be converted to form a by purine-analogues with 10(-7) M concentration only if inorganic phosphate is included in the incubation mixture. Pyridoxal phosphate, phosphoamino acids or other phospho-compounds are incapable to promote the conversion of b form to a form of ODC. These data suggest that purine-analogues may be the in vivo physiological regulators of ODC of T. pyriformis.
梨形四膜虫的鸟氨酸脱羧酶（ODC）可被大肠杆菌或小牛肠碱性磷酸酶灭活。被大肠杆菌碱性磷酸酶灭活的ODC（b型），在10⁻⁴ M浓度的嘌呤核苷或核苷酸作用下可被变构再激活为a型。与琼脂糖结合的小牛肠碱性磷酸酶所灭活的ODC，只有在孵育混合物中加入无机磷酸盐时，才能在10⁻⁷ M浓度的嘌呤类似物作用下转化为a型。磷酸吡哆醛、磷酸氨基酸或其他磷化合物无法促进ODC从b型转化为a型。这些数据表明，嘌呤类似物可能是梨形四膜虫ODC在体内的生理调节剂。
