Folding Kinetics: Equations, Chevron Plots & Mutation Effects

In summary, folding refers to the transition between the native and unfolded state of a protein. This process can be affected by increasing concentrations of denaturant, which causes the protein to unfold at a certain rate. Conversely, folding can also take place at a certain rate when the concentration of denaturant is below a certain threshold. The observed rate constant ln kobs can be represented by an equation and plotted as a Chevron plot, which shows the relationship between denaturant concentration and the rate of folding or unfolding. To determine kfH2O from the plot, one must find the point where the plot intersects with the y-axis. In the case of a mutation affecting the transition state, the Chevron plot will show a different trend
  • #1
biophyscis
2
0
1. Folding can be described as transition between the native and unfolded state. In increasing concentrations of denaturant, a fold disintegrates with a rate

lnKU = ln KU H20 - m ku [denat]

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

lnKf = ln Kf 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?
 
Physics news on Phys.org
  • #2
biophysics said:
1. Folding can be described as transition between the native and unfolded state. In increasing concentrations of denaturant, a fold disintegrates with a rate

lnKU = ln KU H20 - m ku [denat]

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

lnKf = ln Kf 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.
 

1. What are folding kinetics?

Folding kinetics refers to the study of the rate at which a protein or molecule folds into its native three-dimensional structure. It involves understanding the various steps and intermediates involved in the folding process and how they contribute to the overall folding rate.

2. What are equations used to describe folding kinetics?

There are several equations used to describe folding kinetics, including the Arrhenius equation, the transition state theory equation, and the Bell-Evans-Polanyi principle. These equations take into account factors such as temperature, energy barriers, and transition state stability to predict the folding rate of a protein.

3. What are chevron plots?

Chevron plots are graphical representations of the folding kinetics of a protein, showing the relationship between the folding rate and denaturant concentration. The plot typically consists of two phases - an exponential phase at low denaturant concentrations and a linear phase at high denaturant concentrations.

4. How do mutation effects impact folding kinetics?

Mutations can have a significant impact on folding kinetics by altering the stability and structure of a protein. For example, a mutation that destabilizes the native state can decrease the folding rate, while a mutation that stabilizes the native state can increase the folding rate.

5. What is the importance of studying folding kinetics?

Studying folding kinetics is important for understanding the fundamental principles of protein folding and how it relates to protein structure and function. It also has practical applications in fields such as drug design and protein engineering, where understanding folding kinetics can aid in the development of more stable and functional proteins.

Similar threads

Folding Kinetics: Equation & Chevron Plot
    • Biology and Chemistry Homework Help
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top