Thymidine phosphorylation in wheat: analysis of phosphate transfer from ATP to thymidine

Extracts of wheat (Triticum vulgare Vill. Triticum aestivum L.] var. Lemhi) seedlings contain thymidine-phosphorylating activity with ATP, ADP, or AMP and nucleotide hydrolase activity (ATP → → AMP). The synthesis of ³²P]dTMP exclusively from α-³²P]ATP with none detectable from γ-³²P]ATP demonstrates the absence of thymidine kinase and the presence of nucleoside phosphotransferase as the only observable thymidine-phosphorylating enzyme.