Enzymes relevant to cancer chemotherapy II. Heterogeneity of rat kidney uridine kinase following chromatography on Sepharose 6B coupled to N4-(5-amino-Pentyl)-cytidine.

Using Sepharose 6B coupled to N4-(5-aminopentyl)-cytidine at least three different peaks of rat kidney uridine kinase activity have been found. Prior to affinity chromatography the enzyme was partially purified by ammonium sulfate precipitation. The elution was carried out with 0.15 M NaCl or with 0.012 M ATP. The importance of different forms of uridine kinase in eukaryotic cells for cancer chemotherapy with uridine and cytidine analogues is discussed.