Fig. 3From: Feline thymidine kinase 1: molecular characterization and evaluation of its serum form as a diagnostic biomarkerSteady-state kinetic analysis of feline TK1 with the phosphate acceptor as the variable substrate. Plots of the initial velocity versus the substrate concentration, dThd (A), dUrd (B), Urd (C) and dGuo (D). The ATP concentration was kept at 1 mMBack to article page