【加油(邀請:154179)】評論

＊脂肪酸β-oxidation產生Acetyl-CoA的步驟：fatty acid→fatty acyl-CoA(酵素: acyl-CoA synthetase，消耗2個ATP  (ATP+CoA→AMP+PPi))在粒線體內膜形成fatty acyl-CoA。fatty acyl-CoA→Δ2 -trans-enoyl-CoA(具有雙鍵) (酵素: acyl-CoA dehydrogenase，去掉的氫則由Fp（Flavoprotein）接收形成 FpH2(即產生1個FADH2)Δ2 -trans-enoyl-CoA→L(+)-β-3-hydroxyacyl-CoA       (酵素: Δ2 - enoyl-CoA hydratase，加入1個H2O)L(+)-β-3-hydroxyacyl-CoA→β-3-ketoacyl-CoA(酵素: L(+)-β-3-hydroxyacyl-CoA dehydrogenase，去掉的氫則由NAD+接收，產生1個NADH)β-3-ketoacyl-CoA→acetyl-CoA+acyl-CoA(酵素: β-3-ketoacyl thiolase(硫解酶)=acyl-CoA acetyl-transferase，（和一開始的Acycl-CoA比起來少兩個碳）以上五個步驟重複進行直到脂肪酸全部變成acetyl-CoA。 ＊檸檬酸循環之步驟:pyruvate由細胞質(cytosol)進入粒線體基質(mitochondria)pyruvate+NAD+→acetyl-CoA+CO2+ NADH+ H+(酵素: pyruvate dehydrogenase complex, 消耗1個CO2，產生1個NADH，需要TPP(VitB1)、FAD(VitB2)、NAD+(VitB3)、CoA-SH(VitB5)、lipoate=lipoic acid(擬脂酸=硫辛酸))oxaloacetate(草醋酸=丁酮二酸) +acetyl-CoA→citrate(檸檬酸)+CoA-SH(酵素: citrate synthase)citrate→cis-aconitate (中間過渡物)+H2O(酵素: aconitase，脫去1個H2O)cis-aconitate(中間過渡物)+ H2O→isocitrate(異檸檬酸)(酵素: aconitase，加入1個H2O)isocitrate+NAD+→α-ketoglutarate(α-酮戊二酸)+NADH+ H++CO2(酵素: isocitrate dehydrogenase，消耗1個CO2，產生1個NADH)α-ketoglutarate+NAD+→succinyl-CoA(琥珀醯基輔酶A)+NADH+H++CO2(酵素: α-ketoglutarate dehydrogenase，消耗1個CO2，產生1個NADH )succinyl-CoA+GDP→succinate(琥珀酸)+GTP(酵素: succinyl-CoA synthetase=succinate thiokinase)succinate+FAD→fumarate(胡延索酸)+FADH2(酵素: succinate dehydrogenase，產生1個FADH2)fumarate+ H2O→malate(蘋果酸)(酵素: fumarase，加入1個H2O)malate+NAD+→oxaloacetate(草醋酸=丁酮二酸)+NADH+ H+(酵素: malate dehydrogenase，產生1個NADH)oxaloacetate(草醋酸=丁酮二酸) +acetyl-CoA→citrate(檸檬酸)+CoA-SH(酵素: citrate synthase)