I have no idea how to calculate the following task since I don't know the enzyme concentration - can someone help me?
I can't find a similar task to this - so I'm pretty lost.

The KM value for an enzyme is 20 mM. At a koncentration of 30 Mm, how much of the enzyme in percentage is bound to the substrate?

A) 40% B) 50% C) 33% D) 60%

Edited November 6, 20223 yr by Malle

2 hours ago, Malle said:

I have no idea how to calculate the following task since I don't know the enzyme concentration - can someone help me?
I can't find a similar task to this - so I'm pretty lost.

The KM value for an enzyme is 20 mM. At a koncentration of 30 Mm, how much of the enzyme in percentage is bound to the substrate?

A) 40% B) 50% C) 33% D) 60%

Well it's multiple choice, so all you need do is choose an answer that seems sensible.  

What % of the enzyme is bound to the substrate at the Km value? You should know this from the definition of Km.

So then you can ask yourself whether the actual concentration of substrate is higher or lower than this - and choose an appropriate answer accordingly.

(At least, that is how it seems to me. Being a chemist, I didn't know what Km was, so I've had to to look it up. But I think I could now choose the correct answer.) 

 

The Michaelis (enzyme) reaction has a particular form and uses the Michaelis constant.

 

Have you not studied this and is this homework/coursework ?

 

https://en.wikipedia.org/wiki/Michaelis–Menten_kinetics

My suggestion is to rewrite the standard Michaelis-Menten equation in the form (velocity)/V_max = and so forth.  To do so is trivial from the point of view of the algebra involved.