Structure And Function

Question 1

Allosteric binding sites

Answer 1

Binding of a control agent to the allosteric site results in an induced fit causing a change in shape of the active site blocking access to substrate

Question 2

Reversible inhibitors

Answer 2

Equilibrium exists between bound and unbound drug therefore inhibition is reversible
Increase in natural substrate concentration will decrease effectiveness of drug

Question 3

Competitive binding

Answer 3

Design of a drug to strengthen binding interactions can inhibit or switch off enzyme function

Question 4

Irreversible inhibitors

Answer 4

Bind irreversibly to the active site usually by forming covalent bonds with amino acid residues

Question 5

Compare reversible and irreversible inhibitors

Answer 5

Reversible inhibition is preferred over irreversible inhibition
Irreversible inhibitors contain reactive functional groups which can react with other biological molecules resulting in toxic side effects
Irreversible are not competitive since they are permanent bound to active site

Question 6

Uncompetitive inhibitors

Answer 6

Bind reversible to the enzyme substrate complex
Increase substrate concentration will not effect inhibition

Question 7

Non competitive inhibitors

Answer 7

Binds to allosteric site to inhibit enzyme activity, but do not inhibit substrate binding

Question 8

Transition state analogues

Answer 8

A drug that binds to and inhibits an enzyme because the drug resembles the transition state
Should bind more strongly than substrate to product to effectively work

Question 9

Suicide substrate

Answer 9

Suicide substrate are harmless molecules until converted within the enzyme active site to a highly reactive species, which can form covalent bond to amino acids in active site