Enzymes Lab Report

The purpose of this lab was to determine the effects of changes in variables such as temperature, pH and concentration on catalase enzyme activity. Proteins are organic compounds made up of amino acid subunits consisting of carboxyl and amino functional groups, linked together by peptide bonds through condensation reactions. They are an essential part of all living organisms. Enzymes are “biological catalyst used to speed up chemical reactions (Athanasopoulos, 2014). Normally, for chemical reactions; “reactant molecules must collide with enough force [energy] and with the correct geometric orientation for bond breaking to occur” (L. Morris, 2014). As for energy, because the structure of proteins can be denatured at high temperatures, living
Enzymes speed up chemical reactions by lowering the ∆EA, which normally would take too long; this process is called catalase (Athanasopoulos, 2014). According to a study; Modern Topics in Biochemistry by Bennett, T.P., and Frieden, E (1969) enzymes “increases the speed of chemical reactions, without undergoing any permanent chemical change. They are neither used up in the reaction nor do they appear as reaction process”. The enzyme uses amino acid R-groups to weaken the bonds in the substrate; a reactant or molecule, the substrate is what binds to the active site, which is a specific region of an enzyme. Because enzymes are able to change and adjust their shape, they can accommodate to the desired substrate, this is referred to as induced fit (Athanasopoulos, 2014). According to a 1888 theory by Swedish chemist Savante Arrhenius; the substrate and enzyme formed some intermediate substance...known as the enzyme substrate-complex. However there are certain types of chemicals known as inhibitors that bind to specific enzymes
The optimal temperature, at which enzyme catalytic activity is at its greatest, is usually the human body temperature (37.5oC) in human cells. As said earlier, enzymes can be denatured, this occurs when the temperature is heated above the body temperature (>37.5oC), this is because the structure begins to break down, due to the inter- and intermolecular bonds being broken down as the enzyme molecules gain more kinetic energy. Moreover, pH effects the enzymes in a similar way to temperature, enzymes have an optimal pH at which it works best at. Although in general enzymes work within a small range of pH, when there is a change in pH, it can break apart the intra- and intermolecular bonds within which then changes the shape of the enzyme, this causing the effect in the reaction. Lastly, concentration, an increase in the substrate concentration only alters the speed of the reaction to a certain point, going any higher will not cause much significance afterwards. This is because “it will no longer be the limiting factor, and another factor will be limiting the rate of [the] reaction” and since the substrate will get used up “the rate of reaction will decrease”