# Enzyme Catalysis Equation

I'm trying to build an enzyme catalysis equation and end up like this:

$$\label{QSSA-cat-MM} E \begin{matrix*}[l] \rotatebox{40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}}\\[-0.5em] \rotatebox{-40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}}\\[1em] \end{matrix*} \begin{matrix*}[l] \hspace{1.7cm} E+P\\[-1em] ES \hspace{0.1cm} \rotatebox{40}{\xrightarrow{k_{cat}}} \\[-1.3em] \hspace{0.6cm} \rotatebox{-40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}\\[0em] \hspace{0.6cm} \rotatebox{40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}}\\[-1em] SE \hspace{0.1cm} \rotatebox{-40}{\xrightarrow{k_{cat}}} \\[-1em] \hspace{1.5cm} E+P \end{matrix*} \hspace{-1cm} SES \xrightarrow{k_{cat}}E+2P$$


The shape is exactly this, but it's not aligned.

There is some other way to do this?

• Not aligned in which way? After adding the necessary closing brace } I get this as output. Are you referring to the 3 right-most expressions? If so, what alignment were you interested in? Be specific. – Werner Oct 14 '18 at 16:07
• It is not symmetric – Thales Souza Freire Oct 14 '18 at 20:03
• But there are sooo nice packages like chemfig around. Or is there a reason you don't like those? – marmot Oct 15 '18 at 2:57

Here is an option, depending on what you mean by symmetric:

\documentclass{article}

\usepackage{mathtools,graphicx,eqparbox}

\begin{document}

$$E \begin{matrix*}[l] \rotatebox{40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}} \\[-0.5em] \rotatebox{-40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}} \\[1em] \end{matrix*} \begin{matrix*}[l] \hspace{1.7cm} E+P\\[-1em] ES \hspace{0.1cm} \rotatebox{40}{\xrightarrow{k_{cat}}} \\[-1.3em] \hspace{0.6cm} \rotatebox{-40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}} \\[0em] \hspace{0.6cm} \rotatebox{40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}} \\[-1em] SE \hspace{0.1cm} \rotatebox{-40}{\xrightarrow{k_{cat}}} \\[-1em] \hspace{1.5cm} E+P \end{matrix*} \hspace{-1cm} SES \xrightarrow{k_{cat}}E+2P$$

\bigskip

$$E \begin{array}{ @{} c @{} } \eqmakebox[R1]{\rotatebox{ 40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}}} \\ \eqmakebox[R1]{\rotatebox{-40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}}} \end{array} \begin{array}{ @{} c @{} } \raisebox{2\normalbaselineskip}{\eqmakebox[R2]{ES}} \\ \raisebox{-2.7\normalbaselineskip}{\eqmakebox[R2]{SE}} \end{array} \begin{array}{ @{} c @{} } \rotatebox{40}{\xrightarrow{k_{\text{cat}}}} \\ \rotatebox{-40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}} \\ \rotatebox{ 40}{\xrightleftharpoons[k_{-1}]{{[S]}k_1}} \\ \rotatebox{-40}{\xrightarrow{k_{\text{cat}}}} \end{array} \begin{array}{ @{} l @{} } \raisebox{3\normalbaselineskip}{\eqmakebox[R4][l]{E + P}} \\ \eqmakebox[R4][l]{SES}\xrightarrow{k_{\text{cat}}} E + 2P \\ \raisebox{-4\normalbaselineskip}{\eqmakebox[R4][l]{E + P}} \end{array}$$

\end{document}


Original display:

Updated display: