slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Ligand Binding Basis for enzyme specificity and molecular recognition. PowerPoint Presentation
Download Presentation
Ligand Binding Basis for enzyme specificity and molecular recognition.

Loading in 2 Seconds...

play fullscreen
1 / 27

Ligand Binding Basis for enzyme specificity and molecular recognition. - PowerPoint PPT Presentation


  • 73 Views
  • Uploaded on

Ligand Binding Basis for enzyme specificity and molecular recognition. A case where a single ligand (L) binds to a single receptor (R). [L] and [R] are concentrations of free L and free R. [LR] is the concentration of the complex.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Ligand Binding Basis for enzyme specificity and molecular recognition.' - reed-frazier


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Ligand Binding

Basis for enzyme specificity and molecular recognition.

A case where a single ligand (L) binds to a single receptor (R).

[L] and [R] are concentrations of free L and free R. [LR] is the concentration of the complex.

Kd is the equilibrium dissociation constant with units of molar (M).

Ka is the equilibrium association constant = 1/Kd with units of M-1.

k1 (M-1s-1) association rate constant

k-1 (s-1) dissociation rate constant

slide2

Free energy of interaction

The free energy change on binding a ligand to its receptor can be calculated from the Kd or Ka

G0 = -RT ln (Ka) = RT ln (Kd).

More negative the G0 the stronger the binding.

slide3

Derivation of single binding equilibrium

The fraction of bound protein

= moles of ligand bound per mole of protein

= X

slide10

[dTTP*-protein]uM

dTTPs bound per hexamer =

[hexamer]

slide15

Hepatitis C virus helicase protein

4 W, 17 Y

protein

DNA

Minimal DNA binding site?

Free energies of interactions?

cooperativity in binding?

slide16

The fluorescence of NS3h protein was measured in the presence of different amounts of a 10-nt long ssDNA substrate. The fluorescence signal was corrected for dilution and inner filter effect and fit into Equations 2-4 to obtain n and Kd (n = 0.91  0.02, Kd = 7.4  0.7 nM).