AAT Bioquest

What is the relationship between proteinase K and calcium?

Posted September 7, 2023


Proteinase K binds to two Ca 2+ ions to assist in maintaining the stability of the enzyme, especially when exposed to increasing temperatures. Additionally, calcium protects proteinase K from autolysis. It has been shown the Ca(2+) removal decreased the enzyme’s overall thermal stability and to a certain degree the substrate affinity. Calcium however is not necessary for proteolytic activity and is not directly involved in the catalytic mechanism.

Additional resources

The effect of calciums on molecular motions of proteinase K


Amplite® Universal Fluorimetric Protease Activity Assay Kit *Green Fluorescence*