THE EFFECT OF DROPLET DYNAMICS ON THE ENZYME-KINETIC REACTIONS BY YEAST ALCOHOL-DEHYDROGENASE IN REVERSE MICELLES

The kinetics of alcohol oxidation catalysed by yeast alcohol dehydroge nase have been studied in the Aerosol OT reverse micellar system. It h as been found that the rate of the reaction is dependent on the dynami c properties of the droplet as well as on the catalytic activity of th e enzyme molecule. The dynamic properties of the droplets have been ch aracterized by the term ''substrate transfer coefficient'' I which is a measure of the droplet diffusion and the interdroplet interaction ra te. Any factor such as droplet volume fraction, temperature or rigidit y of the surfactant monolayer of the droplet which affects either or b oth of the above, namely droplet diffusivity and interdroplet interact ion, would influence the kinetics of the enzyme-catalysed reaction in a reverse micellar system. From the kinetic model it has been shown th at when I is small enough in comparison with the intrinsic activity of the enzyme, the reaction rate is directly proportional to I, whereas when the value of I is large enough the reaction rate is controlled by the enzymatic activity.