MITOCHONDRION LABEL leucine BCAT2 α-ketoglutarate glutamate α-ketoisocaproate CoA NAD+ CO2 NADH isovaleryl-CoA LABEL BCKDHA BCKDHB DBT DLD isoleucine CoA NAD+ CO2 NADH 2-methylbutyryl-CoA α-ketoglutarate glutamate α-keto-β-methylvalerate valine CoA NAD+ CO2 NADH isobutyryl-CoA α-ketoglutarate glutamate α-ketoisovalerate BCKDK PPM1K LABEL BCKDHA BCKDHB DBT DLD P