Effect of an Increasing Substrate Concentration on Enzyme Activity Rate
Abstract
The reaction rate of an enzyme can be affected by many factors, and the purpose of this experiment was to find out how an increasing substrate concentration influences the rate of an enzyme activity; we obtained data from recording the absorbance of the samples which contain the same amount of potato juice (enzyme oxidase) and different amount of catechol (substrate) while holding pH and temperature constant. Our findings illustrate that the rate of enzyme activity is only influenced by substrate concentration at low level of substrate concentration, and as substrate concentration increases, the rate becomes independent of the substrate concentration and proceeds at a constant state.
Introduction
The fact that enzymes function as biological catalysts has a significant value in millions of living organisms including human beings. As catalysts, enzymes, which are mostly proteins, speed up various reactions by lowering the activation energy they required. The mechanism behind enzyme catalysis involves the binding of substrate to the active site of the enzyme, which proceeds to form an enzyme-substrate complex by process called ¡§induced fit¡¨ and destabilizes the chemical bonds of the substrate, therefore reduces the energy needed for the reactants to reach the transition state (intermediate). The rate of enzyme reaction can be affected by many factors such as temperature, pH, and substrate concentration; every enzyme has its optimum range of temperature and pH, outside that range the enzyme is rendered inactive and is said to be totally inhibited(Logan, 1996). But how is the catalytic rate of an enzyme related to the substrate concentration? With the purpose to understand the effect of substrate concentration on the rate of enzyme activity, in this experiment we obtained samples which contain the