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enzyme activity in inhibition assay - (Oct/28/2010 )

I have some problem with the analysis of inhibition test. Some manuscripts talk about activity of the enzyme in the presence of inhibitor, relative to control using no inhibitor. What does activity means?Percentage of inhibition is a sort of measure of enzyme activity?How can I calculate this activity from a spectrophotometric assay perfomed at various inhibitor concentration?



how do you evaluate your assay?

you say it is spectrophotometric. are you determining the change in absorbance per minute (or hour)?

when you determine the rate of change in absorbance for the inhibited assays you compare to the control assay. your rate will be some percentage of the control, subtract that from 100 and you have the percent inhibition.


I perform a continous assay, monitoring the decrease of absorbance in the presence of the potential inhibitor in the mix reaction over a time of 20 minutes.

Hence, is the activity of the enzyme equal to the percent inhibition?