Cell Metabolism 2 - Fatty Acid Metabolism

Question 1

What is Beta-oxidation?

Answer 1

Fatty acid oxidation that occurs in the mitochondria and results in the generation of acetyl CoA

Each cycle = 1x FADH2 + 1x NADH

Question 2

Step 1: synthesis do acyl CoA

Answer 2

Fatty acid + ATP + HS-CoA —> acyl CoA + AMP + PPi

Question 3

Step 2: carditides shuttle

Answer 3

Acyl CoA + carnitine —> acyl carnitine

Acyl carnitine moved into the matrix through a translocase

Acyl carnitine converted back to carnitine and acyl CoA regenerated

Enzyme: carnitine acyl transferase

Question 4

Primary carnitine deficiency

Answer 4

Autosomal recessive disorder

Symptoms include encephalopathies - cardiomyopathies, muscle weakness and hypoglycaemia)

Mutations in gene SLC22A5 —> encodes carnitine transporter —> reduced ability to take up carnitine
—> needed for beta-oxidation of fatty acids

Question 5

Beta-oxidation

Answer 5

Mitochondria

Acyl CoA undergoes oxidation, hydration, oxidation and thiolysis reactions

Results in production of acetyl CoA + a acyl CoA species 2 C shorter than the original

Question 6

Beta-oxidation of palmitic acid

Answer 6

Generates acetyl CoA

Keeps removing 2 C units

16C palmitoyl CoA molecule —> 7 beta-oxidation reactions
= 8 molecules of acetyl CoA

Therefore produces 7x FAHD2 + 7x NADH

Question 7

Ketone body formation

Answer 7

Happens when fat breakdown predominates