- 2 x acetyl CoA to acetoacetyl-CoA using thiolase
- reversal of final step of beta oxidation
- Acetoacetyl-CoA to HMG-CoA through HMG-CoA synthase.
- Requires additional Acethyl-CoA and H20
- HMG CoA to Acetoacetate through HMG-CoA lyase
- Produces acetyl-CoA
- Acetoacetate to acetone through acetoacetate decarboxylase (removal of CO2)
- OR Acetoacetate to Beta hydroxybutyrate through beta-hydroxybutyrate dehydrogenase (NAD -> NADH)