Merck, A7646-5KU, Apyrase from potatoes

Application
At least two isoenzymes are found in different varieties of S. tuberosum: one with a high ATPase/ADPase ratio (∼10) and another with a low ratio (∼1).
Reaction: ATP → ADP+Pi → AMP+2Pi.
Apyrase is used to hydrolyze nucleoside triphosphates and diphosphates. For hydrolysis of organic di and triphosphates, the optimal pH is 6, and for inorganic substrates, the optimal pH is 5.1 Apyrase, from Sigma, has been used in inhibition studies of platelet-aggregation. The enzyme has been used to assess the possibility of ATP involvement in intestinal lamina propria Th17 cell differentiation.
Biochem/physiol Actions
Apyrase is found in all eukaryotes and some prokaryotes. Apyrase, from potato, has a crucial role in regulating growth and development. Apyrase is involved in the inactivation of synaptic ATP as a neurotransmitter following nerve stimulation and in the inhibition of ADP induced platelet aggregation to prevent thrombosis. Divalent metal ions are required for activity and best activity is observed with calcium ion at 5 mM. The molecular weight of the protein is found to be approximately 45 kDa.
Packaging
Sold on the basis of ATPase units
Analysis Note
Contains ≤ 5% acid phosphatase.
Other Notes
Mixture of high and low ratio isoenzymes.
One unit will liberate 1.0 μmole of inorganic phosphate from ATP or ADP per min at pH 6.5 at 30 °C.