Fig 3. Thin-layer chromatography assays for the adenosine kinase activity and the inhibitory effect of cordycepin.
(A) Assays for the kinase activities of wildtype and mutant AdoK proteins. Radioactive-labeled ATP and AMP are indicated by arrows on the right of the figure. The protein concentrations are indicated on top of the panels. Quantification assays for the percentage of remaining radioactive ATP in the reactions (upper panels) were performed and correspondingly shown as the lower panels. (B) Competitive TLC assays for the inhibitory effect of cordycepin on the activity of AdoK. An increasing concentration of cordycepin gradually inhibited the activity of AdoK, but did not for hAdoK, and the remaining ATP correspondingly increased. Relative percentages of remaining [γ-32P] ATP in the reaction mixtures were quantified, and the mean values of three independent experiments along with error bars (SD) are shown. The P-values were calculated by unpaired two-tailed Student’s t-test using GraphPad Prism 5. The P-values are indicated on top of the columns.