Quick Guide to Calculating Enzyme Activity

Using Excel to do the Lineweaver-Burk plot

[bronation]

I spent over 3 hours trying to this myself only to find your awesome video. American student here thanking you across the globe for being an incredible teacher and furthering my scientific knowledge by posting this!

[gihchemistry]

The best class I have had about this issue. Thank you!

[maddiebear]

Best teacher. I have found this lovely video after I've already passed the this unit. Very late... but referring to my friend. Keep posting Dr Mark.❤

[mountcarmel]

Thank you professor, you guided me to get out of many confusion.

[gdej]

Dear Dr. Mark Temple, your online tutorial is really clear and useful!!!
So, I used your data to practice calculating enzyme activity, everything is all right, but I'm not sure if the accurate result of Tube 5 of Dilution 1 in Table 2. is

[ebenezerappiah]

Hello Temple thanks for the incredible work you do for some of us struggling with some research procedure. God richly bless you. Please is it possible to get a link to the research article showed in this video. I have been searching for it online but cant seem to get exactly what you were using in this video. Thanks very much

[UWSMarkTemple]

In response to "I'm an aspiring research student Philippines. And I'm currently doing my Research Paper to compare which sample has more enzyme activity. Im gonna use the fruit itself both ripe and unripe, the seeds, leaf and the roots.
Now my problem is that the enzyme calculations on whether who has the greatest amount of enzyme activity present. But I have difficulty in understanding. Please help me. I will indeed be thankful if you support and help me. God bless you and I hope u will see my message."

Response:
The video looks at a purified enzyme activity with a substrate at different concentrations. You seam to be looking at different enzyme preparations with a substrate at the same concentration.
I guess you would be best calculating the ‘specific activity’ of the enzyme,
e.g. Amount (micromole) of product per time (minute) per amount (mg or ml) of enzyme sample, under specified reaction conditions.
This will give a unit of product formation something like micromole/min/mg.
Do control experiments also
e.g. Negative controls with heat denatured plant samples or an extract from another seed/plant type.
A positive control is also important
e.g. a sample with maximum activity to show that the assay is working reproducibly.
Good luck

[DrMuhammadAjmalShah]

Hi Mark Temple, I am performing kinetic of alpha-glucosidase inhibition assay in which enzyme concentration is constant with varying concentration (5 ) of substrate (PNGp) and varying concentrations (3) of inhibitors (isolated natural compounds and positive control acarbose). I got absorbance reading for all samples and control @ 0.5 minute interval for 40 minutes. So how can I proceed now to calculate velocity which is required for plotting and then how to proceed for plotting Linear weaver burk to obtain the enzymatic inhibition mechanism for each sample. I need basic information because i never work before with enzyme

[ahmadmustafa]

Thank you professor, this is very helpful

[manuelvenegas]

Hello, this video is very helpful. Where can I get a hold on this exercise?

[tringuyencsk]

Dear Professor.
If I can not calculate product forming, I just can identify disappearance of substrate concentration follow time. How can I calculate velocity?
Thank you so much, Professor.

[alaechda]

One enzyme unit (U) is defined as the amount of enzyme that transforms 1 µmol of substrate in 1 minute (µmol / min), should we transform absorbance to the amount of the substrate or to the amount of product to have U

[abdurrahmanadam]

Sorry may I ask why it has to be quadratic polynomial to to find the initial rate? Thank you

[zuhropuput]

sorry professor, I want to ask you,
what is the basic principle used in determining the initial rate (v0) ?

[yjcbgkz]

Dear Sir,
Would you please help me in plotting the readings of time dependent GTPase assay using malachite green?

[thoithoisanasoibam]

Sir I am studying inhibitory effect of plant extract on pancreatic lipase enzyme...I am not able to develop a protocol for it....could you please help me ...

[sushmachauhan]

Dear Dr. I would like to know how to calculate specific activity of enzyme. I am doing enzyme assay for Horseradish peroxidase and i have to calculate specific activity. I would be very helpful for me if you will explain me how to do.

[mountcarmel]

would you please explain how you got back to your standard graph to calculate the absorption into the amount instead of using the Beer lambert law?

[viboluno]

Dear Dr. Mark Temple. I have doubt, where X is multiplied by 10? It should be X multiplied by 10 and divided by 1.5 instead? after that why did you multiply it by 4? Thank your for your answer!

[pggroup]

Dear sir, can you please give me the link for "the last week video" that you have pointed out in the beginning of the video. I have tried to search for it but could not find out. I have to study the enzymatic activity and have to do similar kind of experiments. It will be a great help. Kindly respond