Thermodynamic studies on the hydrolysis of cytidine 2':3'-phosphate by bovine pancreatic ribonuclease A. A possible effect of the change of the structure of water.

The temperature-dependence of the ribonuclease A-catalysed hydrolysis of cytidine 2':3'-phosphate was studied in the range of temperatures 0--40 degrees C. A break at 4 degrees C was found both in the Arrhenius and the van't Hoff plots. It is likely that the transition observed is due to the change in the structure of water.