The Effect of Increasing Substrate Concentration on Rate of an Enzyme Reaction

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The effect of increasing substrate concentration on rate of an enzyme reaction.

Enzymes are biological catalysts that lower a reactions activation energy making possible many of the reactions needed for life to exist. Enzymes have a high specificity which have been explained by many theories such as Fischer’s lock and key. Currently the most widely accepted theory is the induced fit hypothesis proposed by Koshland in 1958. This hypothesis solves some of the problems with the Lock and key theory and helps to explain why enzymes only catalyze specific reactions (Joseph et al 1990). Koshland stated that when a substrate begins to bind to an enzyme, interactions of various groups on the substrate with particular enzyme functional groups are initiated inducing a conformentional change from a low catalytic enzyme to a high catalytic enzyme (Silverman 2002). The rate of enzyme controlled reactions is dependent on temperature, pH, and concentration of the substrate and enzyme. If the concentration of a substrate is increased, the rate at which product is formed also increases, up to a maximum value (The Cell).
The kinetic parameter frequently used to characterise an enzyme is the Km (Michaelis constant). The Km is the concentration of a substrate needed to achieve half of the maximum rate of reaction. The maximum rate of reaction is known as Vmax. Vmax depends on how rapidly an enzyme can process the substrate molecule.
Michaelis-Menton equation
Lineweaver and Burk introduced an analysis of enzyme kinetics based on the following rearrangement of the Michaelis-Menten equation
An alternative linear transformation of the Michaelis-Menten equation is the Eadie-Hofstee transformation.
The aim of this work is to investigate the effect of increasing the substrate disodium phenyl phosphate on the rate of an acid phophatase reaction. From the results obtained a Michaelis-Menten Hyperbola, and Lineweaver-Burke linear

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