All reactions within our diagrams are catalytic and are bi-molecular reactions of the form \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$X + Y \rightarrow X + Z$$\end{document}X+Y→X+Z, meaning that Y is transformed to Z and X is a catalyst, that is, X influences the transformation of Y to Z. The edges represent that a source species is catalytic to a target reaction.