Thermodynamic basis of protein-ligand interactions Flashcards Preview

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Flashcards in Thermodynamic basis of protein-ligand interactions Deck (14):
1

What happens if ligand is in significant excess?

When ligand concentration is equal to the dissociation constant, 50% of proteins will be occupied

2

Will kd be higher or lower if binding of ligand and protein is strong?

lower - the stronger the binding, the lower the dissociation and the lower ligand concentration needed to achieve 50% occupancy

3

What happens to water when protein-ligand conformation is formed?

Returns to bulk state

4

Are negative or positive values for enthalpy favourable?

Negative

5

Are negative or positive values for entropy favourable?

Positive

6

For the protein ligand interaction to be favourable, you need to put more energy in than energy you get out. True or false?

False - get more energy out of interaction than you put in

7

The more negative, gibbs energy, the stronger the interaction between protein and ligand and the more energy you get out of the interaction. True or false?

True

8

Is fixing the conformation of protein/ligand favourable?

No because this affects entropy and makes it more negative as there is less disorder (positive entropy is favoured)

9

Is breaking interactions of protein/ligand with water enthalpically favoured?

No - because you are putting energy in to break the bonds

10

Is forming interactions between ligand and protein enthalphically favoured?

Yes - formation of bonds releases energy

11

Are water molecules returning to bulk state entropically favoured?

Yes - as they are less ordered than when they were bonded to ligand/protein

12

Is fenofibrate a lipophilic or hydrophilic drug?

lipophilic

13

Is lisinopril a lipophilic or hydrophilic drug?

hydrophilic

14

Lisinopril has a large number of rotatable bonds. What consequence does this have on enthalpy?

A lot of energy will need to be put in in order to get it into a state where can bind to protein and also need to break bonds with water as it is hydrophilic