Effects of Crowding and Confinement on Enzyme Kinetics

Abstract

Reverse micelles are formed by the aggregation of water inside of a bilayer formed by a surfactant in a non-polar solvent. The nanometer scale pool of water within the reverse micelles provides an environment to study the effects of confinement on enzymes as measured by changes in kinetics. The size of these reverse micelles is directly related to the ratio of water and surfactant. We and others have been studying the effects of crowding, the presence of large concentrations of solutes, on enzyme kinetics. What effect would it have on enzyme kinetics if these solutes were added to the confined environment of the reverse micelle? We have studied the effects of confinement on alpha-chymotrypsin in a system using dioctyl sulfosuccinate (AOT) as a surfactant, isooctane as the non-polar solvent, and N-succinyl-L-phenylalanine p-nitroanilide (SPN) as the substrate. Results will be analyzed within the Michaelis-Menten framework.

* Indicates faculty mentor.