组氨酸解氨酶（Histidine ammonia-lyase，HAL）

$催化反应：$

[[C6：组氨酸（His，histidine ）]]-->[[尿刊酸（UCA）]]

-

\usepackage{chemfig}
\begin{document}
\chemfig{
C	(-[2,1]COOH)
	(<[7.3,1]NH_2)
	(<:[,1]H)
	(-[4.7,1,,1]CH_2
		-[4,1]*5(-N=-[,,,2]HN-=)
	)
}
\begin{tikzpicture} 
\draw [->] (0,0) to node[above] {HAL} (1,0);
\end{tikzpicture}

\chemfig{
HC
	(-[2,1,2]COOH)
	(=[6.7,1,2]CH
		-[6,1](
			=[7.3,1]
			-[5.3,1,,1]NH
			-[4,0.65]
			=[2.7,1]N
			-[0.7,1]
		)
	)
}
+$
\end{document}