= Invertase
<Invertase> is an <enzyme> that hydrolyses <sucrose> into <glucose> and <fructose>. Its name reflects the change in <optical rotation> of the sugar mixture during the reaction. <Optical rotation> therefore provides a measurable signal of chemical conversion, provided other contributions to that signal are controlled. <The Kinetics of Invertase Action by L. Michaelis and Maud L. Menten>[1913, translated pp. 1–3: substrate, acidity, temperature and optical-rotation measurements]{ref}
The classic kinetic study measured initial <reaction rates> at different <sucrose> concentrations. At low <substrate> concentration the rate rises strongly as more <substrate> is supplied; at high concentration the finite amount of <enzyme> limits the rate. This supplies a concrete motivation for <Michaelis-Menten kinetics>. Product <mutarotation> complicates the optical readout, showing why a convenient physical signal is not automatically a direct count of reaction events.
Back to article page
