Innhibtors

Question 1

What are inhibitors?

Answer 1

Molecules that prevent enzymes from carrying out their normal function

Question 2

How do competitive inhibitors work?

Answer 2

-most are reversible
-structure very similar to substrate
-compete with substrate for active site (blocks)
-reduces e-s complexes, reduces rate
-increasing substrate concentration reduces effects of inhibitor

Question 3

How do non-competitive inhibitors work?

Answer 3

-some reversible, some irreversible
-attach to allosteric site (region that is not active site)
-disrupts enzymes tertiary structure, alters overall shape including active site- cannot bind
-maximum rate decreases

Question 4

What do reversible inhibitors do?

Answer 4

-form temporary covalent bonds

Question 5

What do non-irreversible inhibitors do?

Answer 5

-from permanent covalent bonds
-alter tertiary structure of enzyme (Ag+ and Hg+ cause disulphide bonds to break)
-includes many pesticides (organophosphates inhibit acetylcholinesterase involved in nerve transmission)

Question 6

What drugs are inhibitors?

Answer 6

Penicillin- used to fight bacterial infections, inhibits the enzyme transpeptidase which plays a role in cell wall formation
Ritonavir- antiretroviral drug used to treat HIV, inhibits HIV protease