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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: ranma on September 02, 2009, 05:37:16 PM

Title: Measuring enzyme activity
Post by: ranma on September 02, 2009, 05:37:16 PM
Here's another question...
I know the formula : A=ecl, and what each symbol stands for, but I don't know where to start.


You are assaying isocitrate dehydrogenase, in which NAD+ is converted to NADH. You have a 20 ml sample of protein, which contains a total of 200mg of protein. You take an aliquot of your solution (10ul) and place it in a 1 cm cuvette, in a total volume of 1 ml. After reading baseline values you add isocitrate, and measure the increase in absorbance at 340nm. The increase is 0.15 absorbance units per minute. If 1 unit of enzyme activity is equal to the production of 1 umole/minute of product, how many total units are there in your starting material? The molar extinction coefficient of NADH is 6.3x103.
 ???
Title: Re: Measuring enzyme activity
Post by: renge ishyo on September 06, 2009, 04:41:15 PM
Let us see your attempts so far and then maybe we can figure out where you are going wrong.