Investigating The Effect Of Temperature On Enzyme Activity

pH - Enzymes also have an optimum pH level. The pH of a solution affects the enzyme's secondary and tertiary structures. These bonds make the shape of an enzyme's active site. So, if these bonds are broken, the shape of the active site changes and is distorted. If there is no active site, there is no reaction resulting in no products. If the enzyme is put in a pH that is very different from the optimum pH, it can cause the enzyme to denature.

Enzymes will denature if they get too hot or cold or if the pH of the solution they are in is too high or too

Hypothesis: If the temperature increases, then rate of the chemical reaction will increase as well, and if the temperature decreases, then the rate of reaction will also decrease.

Enzymes are defined as catalysts that speed up chemical reactions but remain the same themselves. The shape of an enzyme enables it to receive one type of molecule and that specific molecule will fit into the enzyme’s shape. Where a substance fits into an enzyme is called the active site and the substance that fits into the active site is called a substrate. Several factors affect enzymes and the rate of their reactions. Temperature, pH, enzyme concentration, substrate concentration, and the presence of any inhibitors or activators can all affect enzymes. Temperature can affect enzymes because if the temperature gets too high, it can cause the enzyme to denature. pH can affect an enzyme by changing the shape of the enzyme or the charge properties of the substrate so that either the substrate cannot bind to the active site or it cannot undergo catalysis. Every enzyme has an ideal pH that it will strive in. Increasing substrate concentration increases the rate of reaction because more substrate molecules will be interacting and colliding with enzyme molecules, so more product will be formed. Inhibitors can affect enzymes and the rate of their reactions by either slowing down or stopping catalysis. The three types of inhibitors include competitive, non-competitive, and substrate inhibition.

Enzymes are very large globular proteins with three dimensional shapes which is vital for enzyme activity as natural catalyst in chemical reactions within the living organisms (7).

However if the temperature exceeds the optimum temperature the enzyme becomes denatured. This is because there is too much energy causing the enzyme molecules to vibrate causing the bonds maintaining their tertiary structure to break. The enzyme unravels causing the shape of the active site to change so it can no longer fit with the substrate.

“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].

In the following experiments we will measure precise amounts of potato extract as well as Phenylthiourea, combined with or without deionized water and in some instances change the temperature and observe and record the reaction. We will also investigate the different levels of prepared pH on varying samples of the potato extract and the Phenylthiourea and record the results. We will answer question such as what is the best temperature for optimum temperature reaction as well as the best pH level for the same reaction.

Each enzyme is very specific and can only catalyze a certain reaction. The specific reaction catalyzed by an enzyme depends on the molecular structure and shape of a small area of the enzyme’s surface called the active site. The active site an attract and hold only its specific molecules. The target molecule that the enzyme attracts and acts upon is called the substrate. The substrate and the active site of the molecule must fit together very closely. Sometimes the enzyme changes its shape slightly to bring about the necessary fit.

Enzymes are very specific in nature, which helps them in reactions. When an enzyme recognizes its specific substrate, the

Enzymes are proteins that work to expedite processes and enhance reactions that occur within cells. Furthermore, enzymes act as catalysts, in which they cause a reaction to be accelerated. However, if these enzymes are exposed to an abnormal environment or withstand extreme conditions such as an increase or decrease in temperature or pH, they will become inactive. Proteins, such as enzymes, must be in a three dimensional structure with active sites to function properly. Acidity, temperature, and concentration all affect the structure and molecular base of amino acids (Controlling Enzymes, 2015). If temperature is decreased, enzyme activity will decrease as well. If temperature is increased, enzyme activity will rise. However, if the temperature

Enzymes are not used up in chemical reactions as they are catalysts, not reactants, therefore they can be reused and remain unchanged. Additionally, enzymes are shape specific, they will catalyse only one type of reaction. The active site of an enzyme must be complementary to a specific substrate in order for binding to occur. Temporary bonds between the enzyme and substrate are established, producing the enzyme-substrate complex. A new form is achieved when the

A catalyst is a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change. An enzyme is a globular protein which acts as a catalyst for biochemical reactions. An enzyme contains an active site which is the region on the surface of an enzyme to which substrates bind and which catalyzes the reaction. Change in temperature can affect the rate of activity of enzymes. Low temperatures result in sufficient thermal energy for the activation of a given enzyme-catalyzed reaction to be achieved. Higher temperatures will cause enzyme stability to decrease as the thermal energy disrupts the hydrogen bonds holding the enzymes. At an optimal temperature, the rate of enzyme will be at its peak. Increasing

The entirety of this experiment was to conclude if temperature had an effect on enzyme activity. The experiment tested the perimeters of enzyme activity and to see whether or not the temperature had an effect on the amount of substrate produced. Enzymes are especially well known for being catalyst within a reaction (Royal Society of Chemistry). A catalyst is, in this case an enzyme, which speeds up a reaction by lowering the activation energy required to start the reaction (Royal Society of Chemistry). Previous research has shown that while the temperature rises reacting molecules have more kinetic energy. The more kinetic energy each molecule has, the greater the chance of reaching its point of highest catalytic activity (Royal Society of

Enzymes are natural catalysts that work from the ability to increase the rate of reaction by decreasing the activation energy of a reaction. (Blanco, Blanco 2017) An enzyme can do this 10^8- to 10^10 fold, sometimes even 10^15 fold. (Malacinsk, Freifelder 1998) The substrate will momentarily bind with the enzyme making the enzyme-substrate complex, of which the shape of the substrate is complimentary to the shape of the active site on the enzyme it is binding with. There are two main theories as to how an enzymes and substrates interact, the lock-and-key model and induced fit theory. The lock-and-key model suggests that the enzyme has a specific shape that fits the substrate and only that substrate. The induced fit theory says the active site and substrate are able to change shape or distort for the reaction to take place with (Cooper,