Michaelis Menten Equation

Memory Hack💡

One of the trickiest things in this section is typically people forgetting what Km is. What helps me remember Km is to think of it as "K middle" which tells me that it is the half way point to all of the substrates being saturated with substrate.

Notes

The Michaelis Menten equation is: 

Vo= Vmax[S] / (Km + [S]) 

This is used to generate a graph shown above. 

Lets break this graph down: 

This is different from the other graph (to find Vo) that showed us product as a function of time. Here, we are looking at initial velocity as a function of substrate concentration. This allows us to see how the initial velocity changes as substrate concentration increases. 

Lets define some of these terms: 

“Vmax”: This is the value where all the enzymes are saturated with substrate. There is no possibility of the graph going above this amount, as there cannot be any more enzymes saturated if all of the enzymes are saturated. 

“Km”: This value is the concentration of substrate at ½ of the Vmax. So, the amount of substrate needed to saturate ½ of the enzymes. 

When this information is utilized, we are able to determine an unknown. This is not just used to solve for Vo, but can solve for any of the variables in the equation, provided we have enough information.