4. TAC：α-酮戊二酸氧化脱羧：α-酮戊二酸脱氢酶（KGDH）

第2次脱氢

称谓

α-酮戊二酸脱氢酶 KGDH

催化反应

[[C5：α-酮戊二酸（α-Ketoglutaric acid，AKG）]]+^+$+[[辅酶A]]-->[[C4：琥珀酰CoA（Succinyl-CoA）]]++H^+$+$

$化学方程式：$

-

\usepackage{chemfig}
\begin{document}

\chemfig{
	CH_2
		(-[2,0.5]CH_2-[,0.5]COO^{-})
		(-[6,0.5]C
			(-[,0.5]COO^{-})
			(=[6,0.5]O)
		)
}

+\chemfig{
NAD^+
}

+\chemfig{
CoA-[,0.5]SH
}

\begin{tikzpicture} 
\draw [->] (0,0) to node[above] {KGDH} (1,0); 
\end{tikzpicture}


\chemfig{
	CH_2
		(-[2,0.5]CH_2-[,0.5]COO^{-})
		(-[6,0.5]C
			(-[,0.5]SCoA)
			(=[6,0.5]O)
		)
}
+\chemfig{
NADH+H^+
}
+\chemfig{
CO_2
}
+2.5ATP
\end{document}

-

\usepackage{chemfig}
\begin{document}

\chemfig{
	CH_2
		(-[2,0.5]CH_2-[,0.5]COOH)
		(-[6,0.5]C
			(-[,0.5]COOH)
			(=[6,0.5]O)
		)
}

+\chemfig{
NAD^+
}

+\chemfig{
CoA-[,0.5]SH
}

\begin{tikzpicture} 
\draw [->] (0,0) to node[above] {KGDH} (1,0); 
\end{tikzpicture}

\chemfig{
	CH_2
		(-[2,0.5]CH_2-[,0.5]COOH)
		(-[6,0.5]C
			(-[,0.5]SCoA)
			(=[6,0.5]O)
		)
}
+\chemfig{
NADH+H^+
}
+\chemfig{
CO_2
}
+2.5ATP
\end{document}

-

\usepackage{chemfig}
\begin{document}

\chemfig{
	(-[7.5,0.5]OH)
	(=[2,0.5]O)
	(-[4.5,0.5]
		(-[3.5,0.5]
			(-[4.5,0.5]
				(=[6,0.5]O)
				(-[3.5,0.5]
					(=[2,0.5]O)
					(-[4.5,0.5]HO)
				)
			)
		)
	)
}

+\chemfig{
NAD^+
}

+\chemfig{
CoA-[,0.5]SH
}

\begin{tikzpicture} 
\draw [->] (0,0) to node[above] {KGDH} (1,0); 
\end{tikzpicture}

\chemfig{
	(-[5,0.8]
		(-[3,0.8]
			(-[5,0.8]HOOC
			)
		)
	)
	(=[2,0.8]O)
	(-[7,0.8]S
		-[1,0.8]CoA
	)
} 
+\chemfig{
NADH+H^+
}
+\chemfig{
CO_2
}
+2.5ATP
\end{document}

-

O=C(O)C(=O)CCC(=O)O.
CC(C)(COP(=O)(O)OP(=O)(O)OCC1C(C(C(O1)n2cnc3c2ncnc3N)O)OP(=O)(O)O)C(C(=O)NCCC(=O)NCCS)O>>
O=C(O)CCC(=O)SCCNC(=O)CCNC(=O)[C@H](O)C(C)(C)COP(=O)(O)OP(=O)(O)OC[C@H]3O[C@@H](n2cnc1c(ncnc12)N)[C@H](O)[C@@H]3OP(=O)(O)O.
C(=O)=O

蓝细菌相关步骤

蓝细菌缺乏该酶，而是具有

• 新型α-酮戊二酸脱羧酶

• 琥珀酸半醛脱氢酶

直接转化为[[C4：琥珀酸（succinic）]]

下一步

[[5. TAC：琥珀酰辅酶A转化为琥珀酸：琥珀酰辅酶A合成酶（SCS）]]