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Question regarding Michaelis-menten plot and equation

  1. Jan 12, 2012 #1
    1. The problem statement, all variables and given/known data

    I have a michaelis-menten plot and I need to see if it fits the chemical rate equation.

    2. Relevant equations

    J=JMAX ( / KM + )

    3. The attempt at a solution

    I can get values for the entire equation from the plot. My idea was to choose a value of J and insert the relevant values into the equation. then compare the solution to my chosen value of J. Does this make sense? i have a feeling there is some major mathematical flaw somewhere!
  2. jcsd
  3. Jan 19, 2012 #2


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    Homework Helper

    For a reasonably good idea at least, what is J when S is large, S>>Km ?

    Although this is not usually recommended for fitting the curve.

    I can't believe they have thrown this task at you and nowhere in your handouts or books is there any idea of how you home in on these constants. It is in almost every My First Book Of Biochemistry.

    But if you really have to work it out, you are supposed to transform your equation into one of several forms where you can plot one parameter calculated from the experiments against another and the result is a straight line if your equation is obeyed. You then find - calculate with a scientific calculator - the straight line that best fits the points. However if you don't know how to do this best fit, drawing the best line by eye with ruler is (secret) just as good for now, though frowned on by academics and journals of a certain level.
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