Fatty acid Synthesis

formula for fatty acid synthesis

8 acetyl-coa + 7 ATP + 14 NADPH —> palmitic acid + 7 ADP + 7 P + 14 NADP+ + 6 H2O + 8 coa + 14 H+

where does fatty acid synthesis take place?

cytoplasm

steps of fatty acid synthesis

• acetyl coa + CO2 —> malonyl coa

  • use up 1 ATP

  • enzyme: acetyl coa carboxylase

• malonyl coa + 2 NADPH —> palmitic acid

  • loss of H2O

  • loss of CO2

  • enzyme: fatty acid synthase

what is the rate-limiting enzyme of fatty acid synthesis?

• acetyl-coa carboxylase

• acetyl-coa to malonyl-coa

what inhibits acetyl-coa carboxylase?

• glucagon

• fatty acids

what activates acetyl-coa carboxylase?

• citrate

• insulin

what is the role of citrate in fatty acid synthesis?

• acetyl-coa cannot leave the mitochondria and synthesis must happen in the cytoplasm

• acetyl-coa —> citrate and leaves the mitochondria

• turns back into acetyl-coa for synthesis

beta-oxidation purpose

• break down palmitic acid into acetyl-coa during starvation for energy

• loss of 2 carbons at a time

beta-oxidation steps

• fatty acid + coa-SH —> acyl coa

  • use up ATP

  • enzyme: acyl synthetase

• acyl-coa + carnitine —> acylcarnitine

  • enzyme: carnitine acyl transferase I

• acylcarnitine enters the mitochondrial matrix through the acylcarnitine transporter

• acylcarnitine —> acyl coa + carnitine

  • enzyme: CAT II

• acyl coa + carnitine + FADH + NADH —> acetyl coa + acyl coa (2 carbons shorter)