Podcast
Questions and Answers
What happens to fatty acids during oxidation?
What happens to fatty acids during oxidation?
Which enzyme is essential for the activation of fatty acids in the outer mitochondrial membrane?
Which enzyme is essential for the activation of fatty acids in the outer mitochondrial membrane?
What is required for the penetration of long-chain acyl-CoA into the inner mitochondrial membrane?
What is required for the penetration of long-chain acyl-CoA into the inner mitochondrial membrane?
Which enzyme catalyzes the reformation of acyl-CoA from acylcarnitine?
Which enzyme catalyzes the reformation of acyl-CoA from acylcarnitine?
Signup and view all the answers
How are two-carbon units cleaved from acyl-CoA in β-oxidation?
How are two-carbon units cleaved from acyl-CoA in β-oxidation?
Signup and view all the answers
Which of the following is generated for each cleavage during β-oxidation?
Which of the following is generated for each cleavage during β-oxidation?
Signup and view all the answers
Where in the cell do the steps of fatty acid oxidation primarily occur?
Where in the cell do the steps of fatty acid oxidation primarily occur?
Signup and view all the answers
Which of the following does NOT play a role in the transportation of long-chain fatty acids into the inner mitochondrial membrane?
Which of the following does NOT play a role in the transportation of long-chain fatty acids into the inner mitochondrial membrane?
Signup and view all the answers
Study Notes
Fatty Acid Oxidation
- Fatty acid oxidation is a catabolic process for energy production, converting fatty acids into CO2 and water.
- In humans, glucose is the primary source of energy, but when glucose is depleted, fatty acid oxidation occurs.
Fatty Acid Form
- Fatty acids in the body are mainly present in esterified form, such as acylglycerol.
- Lipolysis of acylglycerol releases fatty acids for oxidation, resulting in only free fatty acids (NEFA) being subjected to oxidation.
Fatty Acid Oxidation Steps
Step 1: Activation of Fatty Acid
- Fatty acid activation occurs in the outer mitochondrial membrane.
- Fatty acids are converted into an active intermediate called acyl-CoA, requiring energy from ATP (two ATP) in the presence of coenzyme A and the enzyme acyl-CoA synthetase (thiokinase).
Step 2: Penetration of Inner Mitochondrial Membrane
- Long-chain acyl-CoA (more than 12 carbon atoms) cannot penetrate the inner mitochondrial membrane.
- Carnitine palmitoyltransferase-I (carnitine acyltransferase-I) enzyme converts long-chain acyl-CoA into acylcarnitine, which can penetrate the inner mitochondrial membrane.
- Carnitine-acylcarnitine translocase enzyme acts as an inner membrane exchange transporter, facilitating acylcarnitine penetration.
Step 3: Reformation of Acyl-CoA
- Acylcarnitine reacts with CoA, catalyzed by carnitine palmitoyltransferase-II (carnitine acyltransferase-II) enzyme, reforming acyl-CoA in the mitochondrial matrix and liberating carnitine.
Step 4: β-Oxidation
- In β-oxidation, two carbons at a time are cleaved sequentially from the acyl-CoA molecule, starting from the carboxyl end, with the addition of one molecule of Co-A-SH.
- The chain is broken between α (2) and β (3)-carbon atoms, hence the name β-oxidation.
- The number of acetyl-CoA produced depends on the number of carbon atoms that form acyl-CoA.
- β-oxidation is catalyzed by several enzymes, known collectively as "fatty acid oxidase", producing one mol of FADH2 and NADH + H+ for each cleavage.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Learn about the catabolic process of fatty acid oxidation, its role in energy production, and the different forms of fatty acids in the body.
