Enzyme Kinetics of Beta-Galactosidase
Abstract
This experiment is to study and measure the enzyme activity of β-galactosidase in the different concentrations of o-Nitrophenylgalactoside (ONPG) using a spectrophotometer. The spectrophotometer was also set at 420nm, a wavelength which is best for recording the absorbance values for the experiment. From the results, 0.9mM ONPG solution has the highest absorbance and 0.1mM ONPG solution has the least. Also, 0.5mM ONPG solution has the highest rate of enzyme activity and it is the most efficient as the enzyme activity of the ONPG solution continues even though the other concentrations of ONPG solution has already stopped the enzymatic reactions as the substrate is already used up.
Introduction
This experiment is to study and measure the enzyme activity using a spectrophotometer and to understand the practical aspects of handling enzymse. This is done when the colourless ONPG is split into galactose and o-Nitrophenol (a yellow compound). The higher the enzyme concentration, the higher the absorbance value. Different molecules absorb different wavelengths of light. For this experiment, the spectrophotometer is set at 420nm, so that we can obtain the best absorbance results.
ONPG →galactose+ o-Nitrophenol
A catalyst is a substance that reduces the activation energy of a chemical reaction, making it energetically viable. It is also used to speed up the rate of a chemical reaction. Enzymes are an example of a catalyst that can be found in the body. They are biological catalysts which are mainly made up of proteins. It is produced to speed up chemical reactions and remain unchanged after a reaction. Enzymes have active site for the substrate to attach to, either to be broken up or joined together. They are also specific in their reactions, they only speed up certain reaction as the active site can only fit a certain substrate and does not work for the other substrates. Also, enzymes will only work properly upon strict optimum conditions. They lower the
This experiment is to study and measure the enzyme activity of β-galactosidase in the different concentrations of o-Nitrophenylgalactoside (ONPG) using a spectrophotometer. The spectrophotometer was also set at 420nm, a wavelength which is best for recording the absorbance values for the experiment. From the results, 0.9mM ONPG solution has the highest absorbance and 0.1mM ONPG solution has the least. Also, 0.5mM ONPG solution has the highest rate of enzyme activity and it is the most efficient as the enzyme activity of the ONPG solution continues even though the other concentrations of ONPG solution has already stopped the enzymatic reactions as the substrate is already used up.
Introduction
This experiment is to study and measure the enzyme activity using a spectrophotometer and to understand the practical aspects of handling enzymse. This is done when the colourless ONPG is split into galactose and o-Nitrophenol (a yellow compound). The higher the enzyme concentration, the higher the absorbance value. Different molecules absorb different wavelengths of light. For this experiment, the spectrophotometer is set at 420nm, so that we can obtain the best absorbance results.
ONPG →galactose+ o-Nitrophenol
A catalyst is a substance that reduces the activation energy of a chemical reaction, making it energetically viable. It is also used to speed up the rate of a chemical reaction. Enzymes are an example of a catalyst that can be found in the body. They are biological catalysts which are mainly made up of proteins. It is produced to speed up chemical reactions and remain unchanged after a reaction. Enzymes have active site for the substrate to attach to, either to be broken up or joined together. They are also specific in their reactions, they only speed up certain reaction as the active site can only fit a certain substrate and does not work for the other substrates. Also, enzymes will only work properly upon strict optimum conditions. They lower the
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