The Nobel Prize in Physiology or Medicine 1953 Presentation Speech for his discovery of the citric acid cycle Sir hans adolf Krebs Great Britain Sheffield University Sheffield, Great Britain 1900-1981 Bic nography
1.化学反应过程 TCA环 step1乙酰CoA与草酰乙酸缩合成柠檬酸 HO HC-COO 0=C- cOo CH;-CScoa →,Bo-c0+soa HC-CO0 柠檬酸合酶 HC-CO0 草酰乙酸 乙酰CA 柠檬酸 pro-s arm -C-SCoA H.C-C-SCOA 画 OA H,C-CO0 H HO-C-COO EB: HO-G-CoOr H.C-COO H.C-COO B: H CitrvI-CoA citrate orok arm C00 H.C-COO Oxaloacetate
Step 1.乙酰CoA与草酰乙酸缩合成柠檬酸 1. 化学反应过程 二、TCA循环
An aldol condensation H2O CoA-SH CH2-C 0 CH3-C +O=C-C00 citrate HO--C-coo S-COA CH,-CO0 synthase CHo-co0 Acetyl-COA Oxaloacetate Citrate CH, -C S-COA HO--C-CO0 CH,-coo AGo'=-322 kJ/mol Citron. CoA The methyl carbon of acety-CoA joins the carbonyl carbon of oxaloacetate; citroyl-CoA is a transient intermediate hydrolysis of the thioester bond releases a large amount of free energy
An aldol condensation The methyl carbon of acety-CoA joins the carbonyl carbon of oxaloacetate; citroyl-CoA is a transient intermediate; hydrolysis of the thioester bond releases a large amount of free energy
1.化学反应过程 TCA环 step1乙酰coA与草酰乙酸缩合成柠檬酸 A Citrate synthase. Citrate is shown in green and CoA pink
Step 1.乙酰CoA与草酰乙酸缩合成柠檬酸 这步反应由 C4 → C6 。 1. 化学反应过程 Citrate synthase. Citrate is shown in green and CoA pink 二、TCA循环
1.化学反应过程 TCA环 step1乙酰CoA与草酰乙酸缩合成柠檬酸 反应的能量由乙酰CoA的高能硫酯键提供,所以使 反应不可逆。此为醇醛缩合反应,先缩合成柠檬酰 CoA,然后水解。 这步反应由C4→C6
Step 1. 乙酰CoA与草酰乙酸缩合成柠檬酸 反应的能量由乙酰CoA的高能硫酯键提供，所以使 反应不可逆。此为醇醛缩合反应，先缩合成柠檬酰 CoA，然后水解。 这步反应由 C4 → C6 。 1. 化学反应过程 二、TCA循环