Beta Galactosidase Experiment

Enzymes are biological catalysts that increase the rate of a reaction by reducing the activation energy required for a reaction. Many enzymes are proteins but not all are; enzymes possess high levels of substrate specificity which they bind to through their active sites. Enzymes display optimal activity at a certain pH level and temperature. Temperature and pH level have drastic effects on enzyme activity; the enzyme will denature if the pH or temperature has changed from its optimal level. Other factors can affect enzyme activity. Coenzymes and cofactors are regulatory molecules that bind with the enzyme to achieve its optimal function. Coenzymes are organic molecules that are required for enzyme function and are usually found in the form of vitamins. Cofactors are inorganic ions that are …show more content…
Regulation can also come in the form of inhibition. Competitive inhibitors compete with the substrate for binding to the active site thus, blocking the enzyme’s activity to the substrate. Noncompetitive inhibitors bind to other sites on the enzyme thereby changing its shape for blocking the substrate (OpenStax Biology, 2017). In this lab, the enzyme beta-galactosidase was used. In the bacteria Escherichia coli, it is used to catalyze the breakdown of lactose into galactose and glucose and to convert lactose into allolactose. The enzyme can also be used in colorimetric assays with substrates such as ONPG, which is used in this lab. The product of ONPG and beta-galactosidase is ONP (Douglas et al 2001). ONP has a yellow color to it at different shades with certain conditions. By measuring the color with a spectrophotometer, the