Learn / Metabolism
Metabolic pathways
Every FMK pathway as a clickable map. Pick one pathway to hammer it — next step, enzyme, regulator, cofactor, and the facts that get tested (NADPH and who needs it, rate-limiting steps, deficiencies) — or set it to all pathways for a mixed drill. Every answer says which enzyme and which pathway.
Lipolysis, carnitine shuttle & β-oxidation
trans-Δ²-Enoyl-CoA
Made from Fatty acyl-CoA (matrix) by Acyl-CoA dehydrogenase (VLCAD / LCAD / MCAD / SCAD by chain length)
Acyl-CoA dehydrogenase (VLCAD / LCAD / MCAD / SCAD by chain length) — Lipolysis, carnitine shuttle & β-oxidation
Cofactors: FAD → FADH₂
Deficiency: MCAD deficiency — most common FAO disorder (AR): fasting/illness-triggered hypoketotic hypoglycemia, vomiting, lethargy, hepatomegaly, sudden death; ↑C8 octanoylcarnitine on newborn screen; avoid fasting, IV dextrose
First oxidation. MCAD handles C6–C10; VLCAD > C14. FADH₂ goes to ETF → CoQ.
Condition cards:MCAD deficiency →VLCAD deficiency →SCAD deficiency →Jamaican vomiting sickness (hypoglycin toxicity) →
Becomes L-3-Hydroxyacyl-CoA via Enoyl-CoA hydratase
Enoyl-CoA hydratase — Lipolysis, carnitine shuttle & β-oxidation
Cofactors: H₂O