Fig. 6. Thermal inactivation of the 4′-phosphatase and the phosphotransferase.
Samples of the partially purified enzyme (heparin-agarose step) were preincubated at various temperatures (30, 37, or 45 °C) for the indicated times. A portion of the incubation was then used to assay for remaining 4′-phosphatase and phosphotransferase activities. The percentage of the activity remaining is normalized to a control sample of the enzyme held on ice.