Pyruvate dHE Complex Pyruvate dehydrogenase complex of e. coli Enzyme Abbreviation Number prosthetic Reaction catalyzed of chains group Pyruvate 24 TPP Oxidative decarboxylation dehydrogenase of pyruvate componen Dihydrolipoyl 24 Lipoamide Transfer of the acetyl transacetylase group to CoA 12 FAD Regeneration of the dehydrogenase oxidized form of lipoamide
Pyruvate dHE Complex
反应不可逆 cO CoA-SH NAD TPP, ipate, NADH O S-COA FAD Mg pyruvate dehydrogenase CH. complex(E,+ E,+ eg) CH3 ruvate Acetyl-COA △G°=-334kJ/mol
丙酮酸脱氢酶复合物 催化丙酮酸氧化脱羧 Mg2+ 反应不可逆
S EAICoenzyme A, CoAl Reactive thiol group Coenzyme A H HH CH 00 N Adenine HS-CH2-CH-N-f-CH2-CHa-N-f-C-C-CH-0-P-0-P-0-CH2o. NiN B-Mercapto O OUCH ethylamine H Pantothenic acid 0 OH Ribose3'-phosphate 0=P-0 0 S-COA 3-Phosphoadenosine diphosphate AcetyI-CoA
辅酶A[Coenzyme A,CoA]
Oxidized Reduced Acetylated form form orm HS-CH2 CHa-c-s-cho HS-CH d Lipoic CH acid CH C=0以酰胺键相连 CH residue ofE CH CH Polypeptide chain of H E2(dihydrolipoyl transacetylase)
硫辛酸、二氢 硫辛酸转乙酰酶 以酰胺键相连
P写合物催化5反M 1)Py脱羧生成羟乙基-TPP 2)二氢硫辛酸转乙酰酶催化羟乙基TPP氧化为乙 酰基,并转移给硫辛酰胺形成酰硫辛酰胺; 3)二氢硫辛酸转乙酰酶催化乙酰硫辛酰胺上的乙 酰基转移给CoA生成乙酰CoA; 4)二氢硫辛酸dE催化还原的硫辛酸再氧化,并 将氢交给FAD生成FADH2E; 5)FADH2使NAD还原
Py dHE复合物催化5步反应 1) Py脱羧生成羟乙基-TPP； 2) 二氢硫辛酸转乙酰酶催化羟乙基TPP氧化为乙 酰基，并转移给硫辛酰胺形成乙酰硫辛酰胺； 3) 二氢硫辛酸转乙酰酶催化乙酰硫辛酰胺上的乙 酰基转移给CoA生成乙酰CoA； 4) 二氢硫辛酸dHE催化还原的硫辛酸再氧化，并 将氢交给FAD生成FADH2 -E； 5) FADH2使NAD+还原