No, EDTA does not inactivate proteinase K. EDTA is used along with proteinase K in order to inhibit metal-ion dependent enzymes such as nucleases. It does not directly affect enzyme activity. Proteinase K is a highly stable protease, and is inactivated through heat at a temperature of 95 degrees celsius for 10 minutes. It is important to note that the addition of EDTA may impact calcium and thus lessen proteinase K activity to a certain degree. This is due to the relationship of calcium and the stability of proteinase K.