One of the obstacles to understanding enzymes is their large size. Each enzyme comprises thousands of atoms, with various sections of an enzyme performing different functions. Other sections of the enzyme can block the active site, allowing only certain molecules access or permitting approaches to the active site from only one direction. Stack chose a well studied and structurally characterized enzyme, galactose oxidase, to mimic. That way, he reasoned, he had a good chance of integrating the important structural features into his model.
Chemistry is chemistry.
To prove that one of life's chemical reactions could be duplicated and even simplified in the lab, Stack and Wang eliminated thousands of extraneous atoms from the enzyme, but retained a structure similar to the enzyme's active site. It had to take an alcohol through the same intermediate steps that the enzyme does. Its structure and spectra had to be similar to the enzyme's. Stack and Wang mixed together their enzyme mimic with an alcohol and added oxygen gas to determine whether their molecule catalyzed the oxidation of alcohols as galactose oxidase does. They found that their model functioned as a catalyst each model molecule aided more than 1,000 alcohol molecules in reacting with oxygen like the natural enzyme.