I want to calculate an enzyme's energy of activation, but I don't have the enzyme's molecular weight to calculate the rate constant or the pre-exponential factor A. This is part of an assignement I have for a virtual lab of enzymology, we use this virtual lab https://www.ucl.ac.uk/~ucbcdab/enzass/enzymass.htm by ucl and the process of it is basically you choose one of 5 enzymes which are fictional enzymes from what I can tell, and then you can perform "expirements" to determine the enzyme's behaviour in different pH environements etc.
I've attached screenshots of the diagrams the virtual lab has produced about how the enzyme reacts to different temperatures. I've concluded that at around 50°C it produces the maximum amount of protein so I've calcuted the maximum velocity using that at 5.86μmol/min. I had to calculate this because since I don't know anything about the actual enzyme I have to calculate the energy of activation using this equation: logk = logA - E / 2.303 * R * T (where logk=logVmax), our professor told us that we have to use this to calculate the energy. She also told us to use excel to calculate logk and logA and create a y=ax+b diagram. I honestly am really struggling to come up with how to use excel in order to do that since I'm really unexperienced with it.
Please refer to the photos below if you want to see the data I have.
You can use the enzymatic activity (in any unit) instead of the rate constant proper, that is just a constant factor that drops out when you determine the slope.
If you have problems using excel, there are many online-courses available, for a list see for example https://www.codespaces.com/best-excel-courses-tutorials.html.
Dr Buxbaum is absolutely correct. Assuming that the activities given in the exercise are Vmax, plot ln V against 1/T (absolute). Since Vmax = kE0, plotting this as a log means that k does not appear in the slope as pointed out by Dr Buxbaum.
Peter
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