Sean - Exam Information

Question 1

List the enzymes, in order, of B-oxidation
(4)

Answer 1

Acyl-CoA dehydrogenase

Enoyl-CoA hydratase

B-hydroxyacyl-CoA dehydrogenase

Thiolase

Question 2

List the molecules, in order, of B-oxidation
(5)

Answer 2

Fatty acyl CoA

Trans-delta2-enoyl-CoA

3-L-hydroxyacyl-CoA

B-ketoacyl-CoA

Fatty acyl-CoA and Acetyl-CoA

Question 3

Name the extra enzyme used in the B oxidation of monounsaturated fatty acids

Answer 3

enoyl-coA isomerase -> it catalyses the conversion of the cis bond into a trans bond

Question 4

Name the extra enzyme used in the B oxidation of polyunsaturated fatty acids

Answer 4

dienoyl CoA reductase - adds two H to the molecule to break remaining double bonds - and by creating another cis double bond

Question 5

How is B-oxidation regulated?
(3)

Answer 5

Malonyl-CoA inhibits carnitine acyltransferase I (carnitine shuttle)

When [NADH] ratio is high, hydroxyacyl-CoA dehydrogenase
is inhibited

When acetyl-coA concentrations are high thiolase is inhibited