|
Specific activity is a convenient method of communicating the amount of enzyme activity you have in each milligram of protein. Specific activity is calculated after each purification step and can be used to monitor the success of that step. To do this calculation you need to know much enzyme activity there is in your sample as well as how much total protein is present. You can calculate the specific activity using the formula below:
For practice, use the values from the two previous sample calculations, 142 units/ml for enzyme activity and 0.6mg/ml for total protein. The specific activity would then be 142 units/ml divided by 0.600 mg/ml or 237 units/mg. ##Note: Specific activity may be lower than expected if the enzyme has been denatured and therefore is no longer active. The protein assay will still detect denatured protein; therefore, the protein part of the calculation will not decrease but the enzyme activity will.
|
