Answer to Question #111530 in Biochemistry for Ibrahim jibrin

Question

Give the regulatory points of citric acid cycle.

Answer 1

These are the regulation steps-

Step 1: First the acetyl CoA (a two carbon molecule) joins with oxaloacetate (4 carbon molecule) to form citrate (6 carbon molecule).

• Step 2: The citrate is then converted to isocitrate (isomer of citrate)
• Step 3: Isocitrate is then oxidised to alpha-ketoglutarate (a five carbon molecule) which results in the release of carbon dioxide. One NADH molecule is also formed in this step.
• Step 4: Here alpha-ketoglutarate is oxidised to form a 4 carbon molecule which picks up coenzyme A forming succinyl CoA. This conversion also forms a NADH molecule.
• Step 5: Succinyl CoA is then converted to succinate (4 carbon molecule) and one GTP molecule is produced.
• Step 6: Succinate is converted into fumarate (4 carbon molecule) and a molecule of FADH₂ is produced.
• Step 7: Fumarate is converted to malate (another 4 carbon molecule).
• Step 8: Malate is then converted into oxaloacetate and NADH is also produced here.