Purchase Solution

Picking the Best Inhibitor when Given Km, Kcat and Ki

Not what you're looking for?

Ask Custom Question

Here are the following numbers I have calculated;
We were given a substrate to plot againist velocity and 3 enzymes to plot as well. From the data:
Enzyme A Ki= 2.575 | Kcat = 50 | Km= 3.33
Enzyme B Ki = 10.33 | Kcat = 16.65 | Km = 33.3
Enzyme C Ki= 1.00 | Kcat = 10 | Km = .2

I'm having trouble understanding which is the best inhibitor because:
A has the highest Kcat- best collision efficiency
C has the lowest Km - the highest affinity for its substrate
C has the lowest Ki- which means it binds the tightest.

Purchase this Solution

Solution Summary

The solution offers guidance and things to consider to pick the best inhibitor out of three when given their respective Kcat, Km and Ki values. The velocity is plotted against the substrate.

Solution Preview


The answer depends on what you want from your inhibitor as there is no clear best chemically.

Km is the substrate concentration required for the enzyme to work at half its maximum rate. Purely competitive inhibition will increase Km but will not alter kcat (and hence the maximum rate). ...

Purchase this Solution

Free BrainMass Quizzes
BioChemistry Basics

This Quiz will test your knowledge of the amino acids used in biological systems

Do You Know Your Macromolecules?

This quiz will assess your knowledge of the macromolecules that are important to living things.

Pregnancy Knowledge

How much do you know about being pregnant? Test your Pregnancy IQ with this quiz!

Feeding Babies

Do you know the science behind feeding babies? Test your knowledge with this quiz.

How Much Do You Know About Genetic Inheritance?

Most of us studied the basics of dominant and recessive genes at some point. However, genetics are much more complicated than this. How far beyond the basics does your knowledge go?