Folding Kinetics: Equations, Chevron Plots & Mutation Effects

[biophyscis]

1. Folding can be described as transition between the native and unfolded state. In increasing concentrations of denaturant, a fold disintegrates with a rate

lnK_U = ln K_U H₂0 - m _ku [denat]

when the concentration of denaturant is above that needed to unfold 50 % of protein. Conversely folding takes place with rate

lnK_f = ln K_f ^H₂O - m _ku [denat]

when the concentration of denaturant is below that needed to unfold 50 % of protein.
Write an equation for the observed rate constant ln kobs and plot it (Chevron plot) as a function of denaturant concentration.
How do you determine from the figure kfH2O?
How will the Chevron plot change when a mutation will affect the transition state?

 

[epenguin]

1. Folding can be described as transition between the native and unfolded state. In increasing concentrations of denaturant, a fold disintegrates with a rate

lnK_U = ln K_U H₂0 - m _ku [denat]

when the concentration of denaturant is above that needed to unfold 50 % of protein. Conversely folding takes place with rate

lnK_f = ln K_f ^H₂O - m _ku [denat]

when the concentration of denaturant is below that needed to unfold 50 % of protein.
Write an equation for the observed rate constant ln kobs and plot it (Chevron plot) as a function of denaturant concentration.
How do you determine from the figure kfH2O?
How will the Chevron plot change when a mutation will affect the transition state?

You are a first-time poster and should read the forum guide in which it is explained that we only try to give homework help to students who have shown they have made an effort on their problem and got lost or stuck somewhere.

There is what looks like a reasonably good article on chevron plots at Wikipedia.