Glad I could help you understand it

Let them hear you. I come in peace. thank you DR for well explanation.

Very kind of you! I’m glad you found it helpful.

I'm glad you found it helpful

Really glad it helped you!

Glad I could help!

Glad you found it useful

Glad it helped you!

I'm glad it helped you

Glad it helped you

Glad it helped you

Glad it helped you

Glad it helped you

You’re welcome, hope you found it useful

You're welcome

Glad you liked it

You’re very welcome! I’m glad you found the video useful

An interesting question, the Vmax will depend on the concentration of active enzyme present so it is not really appropriate to directly compare, Some people try to get around this by expressing as per ug of protein, but then this is not strictly Vmax.

@@NigelFrancis Thank you!

Off top of my head is either nanomoles/min or micromoles/min. This example data was generated using purified enzyme.

@@NigelFrancis my enzymes came in wet cells extract thats why

You’re welcome, hope you found the video helpful

Except this is only an approximation as MM plots never truly plateau

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Yes, you can and this is how I calculated the values for the forecasts.

@@NigelFrancis Of course the advantage of your method is that one has the satisfaction of seeing a traditional L-B plot emerge. Thank you for a superb click-by-click demo of the procedure.

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Hi there, do you mean an example of how to perform the calculation or how the relationship itself is derived?

For example; When I use; My substrate column; 1, 2, 3, 4, 5, 6 mM. Velocity column; 0.25, 0.55, 0.75, 0.92, 1.05, 1.138, 1,14 Vmax: 5,042 Km: 18,59 When I use; My substrate column; 0.1, 0.3, 0.5, 1, 2, 3, 4, 5, 6 mM. Velocity column; 0.06, 0.09, 0.11, 0.25, 0.55, 0.75, 0.92, 1.05, 1.138, 1,14 Vmax : 0,567 Km: 0,954 So differently, Why?

@@zaysiz the short answer is that you cannot have a negative intercept if the enzyme is indeed michealian. Are you absolutely sure about your substrate concentrations? If you’re overestimating, especially at low concentrations this could shift the curve and give the result you describe. The LB plot has a weakness in that the distribution of points is uneven and there is a greater emphasis on lower concentrations, which are inherently more difficult to determine accurately. You could try Eadie or Hanes plots to check your answers.

@@NigelFrancis Thank you for your answer. MM graph looks normal. If I neglect some reactions with low substrate concentration, become LB plot equation to y=ax+b. Should I neglect them for y=ax+b equation? I learned on the internet how to calculate km vmax by Eadie and tried Eadie Hofstee plot. Equation looks normal but I am not sure of the accuracy. I wonder before everything, Do you say that I can not calculate Km and Vmax by y=ax-b equation. I should change substrate concentrations and have to fix the equation for y=ax+b, haven't I?

@@zaysiz You cannot calculate Vmax from a negative y-intercept as the intercept point is 1/Vmax. I suspect that there is either an error in the experimental procedure or that the concentration of the substrate is incorrect and is causing errors that are magnified at the lower concentrations due to the bias in the LB plot.

​@@NigelFrancis Thank you so much for your interest.

The gradient ‘m’ can be calculated using the equation (y2 - y1)/(x2 - x1). I hope that answers your question?

@@NigelFrancis thank you so much

Vmax and Km have different units, Vmax is normally expressed as a unit of concentration/a unit of time (e.g.micromoles/second). Km on the other hand is expressed as a unit of concentration (e.g. micromoles). The Michaelis-Menten plot allows you to approximate Km from the 1/2 Vmax value e.g. if Vmax was 100 then the concentration that would be equivalent to Km would be that where Vmax is equal to 50. It does not mean that Km is exactly equal to the value of 1/2 Vmax. Hope that helps?