Presence, preliminary properties and partial purification of 5-phosphoribosylpyrophosphate amidotransferase from Artemia sp.

5'-Phosphoribosylpyrophosphate amidotransferase, which catalyzes the synthesis of phosphoribosylamine in the de novo synthesis of purine nucleotides, has been detected and partially purified approx. 800-fold from Artemia sp. nauplii. The apparent Km values for 5'-phosphoribosyl 1-pyrophosphate as substrate were 0.7 mM and 0.4 mM in the presence of glutamine and ammonia as nitrogenous sources, respectively, and the enzymatic activity was inhibited by purine 5'-ribonucleotide compounds and 5', 5'''-p1, p4-diguanosine tetraphosphate.