Fat is one of the most important ways we store energy and the term “burning fat”, actually refers to fatty acid oxidation.

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​a cytosolic enzyme called fatty acyl-CoA synthetase adds a coenzyme A molecule to the end of the fatty acid, turning it into a metabolically active fatty acyl-CoA.

​the fatty acid can’t cross the inner mitochondrial membrane when CoA is attached to it. To get around this problem, we need to free the CoA from the fatty acid.

carnitine palmitoyltransferase 1 and 2 TO THE RESCUE!!!

​an enzyme called acyl-CoA dehydrogenase removes 1 hydrogen from the 2nd carbon, and one hydrogen from the 3rd.

Enzyme provides those hydrogens to FAD --> FADH2

​Conversion of the palmitoyl-CoA to enoyl-CoA in the process.

enoyl-CoA hydratase transfers a hydroxyl group, which is an oxygen linked with a hydrogen, from a water molecule on to the beta carbon of enoyl CoA, making beta-hydroxyacyl-CoA.

​beta-hydroxyacyl-dehydrogenase joins the party!!

new electron carrier involved

here --> NAD+ is reduced into

NADH

this oxidation step occurs at the beta-carbon, fatty acid oxidation is also sometimes called beta-oxidation.

Finally, let's cut those 2 alpha and beta carbons off the fatty acid chain

​a 14-carbon acyl CoA that can enter another cycle of beta-oxidation. So the longer the fatty acid chain, the more cycles, and the more energy we make

​THAT IS A LOT OF ENERGY !! TOTALLY WORTH IT RIGHT?