Mitochondrial succinyl-CoA:3-ketoacid coenzyme A transferases 1 and 2 (OXCT1 and OXCT2) are key enzymes for the metabolism of ketone bodies, catalysing the first rate-limiting step of ketone body utilisation in peripheral tissues. In dimeric form, they mediate the transfer of a CoA moiety from succinyl-CoA (SUCC-CoA) to acetoacetate (ACA) to form acetoacetyl-CoA (ACA-CoA) and succinate (SUCCA) (Kassovska-Bratinova et al. 1996, Tanaka et al. 2002). ACA-CoA can be converted to acetyl-CoA which can be utilised by the tricarboxylic acid cycle for energy production.