Question

Which ligand binds tightest? ligand A, with a dissociation constant ( Kd ) of 10−9 M ligand D, with a percent occupancy of 80% at 10 nM ligand B, with a dissociation constant ( Kd ) of 10−3 M ligand C, with a percent occupancy of 30% at 1 μM

Answer 1

Answer:

The answer will be Ligand A with a dissociation constant (Kd) of $10^{-9}$M

Explanation:

When the dissociation constant in the ligand is small (in order of nano) ( $10^{-9}$) it will be more tied. Due to a dissociation constant measures how much a ligand can be able to be separated from the protein so if the number is small it means that the ligand is highly binded to the protein.

On the other hand, the occupancy percentage of the ligand does not imply binding. Conversely, a High-affinity ligand binding with the proteins implies that a relatively low concentration of a ligand is adequate to occupy the maximum ligand-binding site.