α-oxidation of fat

 α-oxidation of fat

It occurs in brain microsomes where it has been found that brain Sphingolipids contain α-hydroxy acids and odd-carbon fatty acids. α -oxidation of phytanic acid is believed to take place entirely within peroxisomes as follows-

1.   Phytanic acid is first attached to CoA to form phytanoyl-CoA.

2.   Phytanoyl-CoA is oxidized by phytanoyl-CoA dioxygenase, in a process using Fe²⁺ and O₂, to yield 2-hydroxyphytanoyl-CoA.

3.   2-hydroxyphytanoyl-CoA is cleaved by 2-hydroxyphytanoyl-CoA lyase in a TPP-dependent reaction to form pristanal and formyl-CoA in turn later broken down into formate and eventually CO₂.

4.   Pristanal is oxidized by aldehyde dehydrogenase to form pristanic acid which can then undergo beta-oxidation.

Propionyl-CoA is released as a result of beta oxidation when the beta carbon is substituted