Enzyme Inhibition Kinetics

Enzymes speed up reactions by lowering the activation energy of the reactants. The speed at which the enzyme turns reactants into products is called the rate of reaction. Several factors impact the rate of reaction, including the number of available reactants. Enzyme kinetics is the study of how an enzyme changes the rate of a reaction. Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...

Enzyme kinetics describes the catalytic effects of enzymes, which are biomolecules that facilitate chemical reactions necessary for living organisms. Enzymes act on molecules, referred to as substrates, to form products. Enzyme kinetic parameters are determined via assays that directly or indirectly measure changes in substrate or product concentration over time. This video will cover the basic principles of enzyme kinetics (including rate equations) and kinetic models. The concepts governing...

Inhibitors are molecules that reduce enzyme activity by binding to the enzyme. In a normally functioning cell, enzymes are regulated by a variety of inhibitors. Drugs and other toxins can also inhibit enzymes. Some inhibitors bind to the enzyme’s active site, while others inhibit enzymatic activity by binding to other sites on the protein structure. Competitive inhibitors occupy the active site of enzymes, making them unable to accommodate the substrate. However, sufficiently high...

Enzyme kinetics studies the rates of biochemical reactions. Scientists monitor the reaction rates for a particular enzymatic reaction at various substrate concentrations. Additional trials with inhibitors or other molecules that affect the reaction rate may also be performed. The experimenter can then plot the initial reaction rate or velocity (Vo) of a given trial against the substrate concentration ([S]) to obtain a graph of the reaction properties. For many enzymatic reactions involving a...

Source: Tay, S. B., et.al. Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases. J. Vis. Exp. (2016)This video demonstrates the process of inhibiting biofilm formation by introducing an enzyme that disrupts bacterial cell signaling. The enzyme prevents the bacteria from producing extracellular polymeric substances, thereby reducing biofilm development on a glass-bottomed microdish. Finally, the biofilm structure is visualized using fluorescent lectins and...