The Effect of Substrate Concentration on the Rate of Activity of the Enzyme Catalase
Background Information:
Enzymes are biological catalysts that increase the speed of chemical reactions without undergoing any physical change. They are neither used up in the reaction nor do they appear as reaction products. All enzyme catalysed reactions are reversible.
Enzymes effectively lower the amount of activation energy required for chemical reactions to start. Some enzymes weaken covalent bonds within the substrate molecule, whereas in other cases this lowering of the activation energy seems to take place because the enzyme holds the substrate molecules in a particular position that increases the
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If the enzymes become denatured the structure becomes disrupted and cannot return to its original shape.
One single enzyme molecule can react over and over (unless its denatured), however it is only capable of combining with a certain maximum number of substrate molecules per minute. This number is called the turnover number. Peroxidase has a very high turnover number and is capable of enzymatically destroying H2O2 (hydrogen peroxide) before it can do much damage, as it is [1]poisonous, corrosive and toxic to most living organisms, especially in too high a concentration. H2O2 is made in cells, it is a bi-product of cell metabolism. The catalase is used to remove H2O2 very quickly from cells by converting it into oxygen and water. The reaction occurs spontaneously, however the catalyst increases the rate dramatically.
2H2O2 2H2O + O2
Introduction: -------------
The aim of this investigation is to research how the concentration of substrate (H2O2 ) affects the rate of reaction of the enzyme catalase (yeast). Whether the rate increases or decreases with the different concentrations of hydrogen peroxide.
In the presence of a catalase, H2O2 willbreak down into water and oxygen (as shown in equation above). As the concentration of the substrate increases, the
Catalase is an important enzyme that protects cells from oxidative damage, which hydrogen peroxide can cause. It is an incredibly efficient enzyme where one catalase molecule can convert millions of hydrogen peroxide molecules each second.
The Effects of Varied Temperatures, pH Values, Enzyme Concentrations, and Substrate Concentrations on the Enzymatic Activity of Catecholase
Enzymes are biological catalysts that speed up chemical reactions, without being used up or changed. Catalase is a globular protein molecule that is found in all living cells. A globular protein is a protein with its molecules curled up into a 'ball' shape. All enzymes have an active site. This is where another molecule(s) can bind with the enzyme. This molecule is known as the substrate. When the substrate binds with the enzyme, a product is produced. Enzymes are specific to their substrate, because the shape of their active site will only fit the shape of their substrate. It is said that the substrate is complimentary to their substrate.
An Investigation on the rate of reaction of the enzyme Catalase on the substrate Hydrogen peroxide.
How does changing the substrate concentration affect the rate of a catalase reaction in an enzyme? Hydrogen peroxide was used as the substrate and the rate was measured by oxygen production.
Lab six requires students to observe the effects of pH and enzyme concentration on catecholase activity. Enzymes are organic catalysts that can affect the rate of a chemical reaction depending on the pH level and the concentration of the enzyme. As pH comes closer to a neutral pH the enzyme is at its greatest effectiveness. Also at the absorbance of a slope of 0.0122 the enzyme is affected greatly. The pH effect on enzymes can be tested by trying each pH level with a pH buffer of the same pH as labeled as the test tube and 1mL of potato juice, water, and catechol. This is all mixed together and put in the spectrophotometer to test how much is being absorbed at 420nm. As the effect on enzyme concentration can be tested almost the same way. This part of the exercise uses different amounts of pH 7-phosphate buffer and potato juice, and 1mL of catechol mixed together in a test tube. Each substance is put in the spectrophotometer at a wavelength set tot 420nm. The results are put down for every minute up to six minutes to see how enzyme concentration affects reaction rate. The results show that the pH 8 (0.494) affects the enzyme more than a pH of 4 (0.249), 6 (0.371), 7 (0.456), and 10 (0.126). Also the absorbance is greatest at a slope of 0.0122 with test tube C that has more effect on the reaction rate, than test tube A, B, and D.
The purpose of this experiment was to record catalase enzyme activity with different temperatures and substrate concentrations. It was hypothesized that, until all active sites were bound, as the substrate concentration increased, the reaction rate would increase. The first experiment consisted of five different substrate concentrations, 0.8%, 0.4%, 0.2%, 0.1%, and 0% H2O2. The second experiment was completed using 0.8% substrate concentration and four different temperatures of enzymes ranging from cold to boiled. It was hypothesized that as the temperature increased, the reaction rate would increase. This would occur until the enzyme was denatured. The results from the two experiments show that the more substrate concentration,
To make the buffer solution you need 0.2 mol dm-3 of Na2HPO4 and 0.1mol dm-3 of citric acid this will give 100cm3 of buffer. Here is how to get the different pH in the buffer solutions:
The purpose of this investigation is to discover the effect of pH on the activity of catalase, an enzyme which plays the integral role of converting hydrogen peroxide into water and oxygen, and discover which pH level it will work at the most efficient rate (the optimum). The original hypothesis states that that the optimum would be at a pH is 7, due to the liver, where catalase usually resides, being neutral. The experiment consists of introducing the catalase to hydrogen peroxide, after exposure to certain solutions; hydrogen peroxide, water and hydrochloric acids, all containing the adjusted pH, and measuring the height of froth formed, an observable representation of the activity of the enzyme. The final data indicated that
An Enzyme is a protein, which is capable of starting a chemical reaction, which involves the formation or breakage of chemical bonds. A substrate is the surface or material on or from which an organism lives, grows, or obtains its nourishment. In this case it is hydrogen peroxide. This lab report will be explaining the experiment held to understand the effects of the changes in the amount of substrate on the enzyme’s reaction.
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.
Within a cell, enzymes are used as a catalyst to increase the rate of chemical reaction. They do not consume themselves, rather they help in increasing the rate of reaction. Within the body, enzymes vary depending on their specific functions. For instance, hydrogen peroxide is a toxic chemical, but it breaks down into harmless oxygen and water. This reaction can be sped up using the enzyme catalyst produced by yeast. Hydrogen peroxide is produced as a byproduct in cellular reaction, because it is poisonous and must be broken down, therefore this reaction is important. The speeding up of the reaction is shown below:
reaction rate increases. If the temperature of an enzyme gets to high the reaction rate will slow
The purpose of this lab report is to investigate the effect of substrate concentration on enzyme activity as tested with the enzyme catalase and the substrate hydrogen peroxide at several concentrations to produce oxygen. It was assumed that an increase in hydrogen peroxide concentration would decrease the amount of time the paper circle with the enzyme catalase present on it, sowing an increase in enzyme activity. Therefore it can be hypothesised that there would be an effect on catalase activity from the increase in hydrogen peroxide concentration measured in time for the paper circle to ride to the top of the solution.
Hydrogen peroxide is a toxic byproduct of cellular functions. To maintain hydrogen peroxide levels the catalase enzyme deconstructs hydrogen peroxide and reconstructs the reactants into oxygen gas and water. The catalase enzyme is found inside cells of most plants and animals. Regulating the levels of hydrogen peroxide is crucial in homeostasis and analyzing it’s optimal conditions for performance is just as important. To understand the optimal environment for this enzyme, they are put into different environments based off protein activity (enzymes are proteins). Catalase samples will be put into different hydrogen peroxide environments based off pH and temperature. The more active the enzyme, the more oxygen and water it will produce. Enzyme activity can be seen through the release of oxygen in the hydrogen peroxide. Since oxygen cannot be accurately measured, the data will consist of the longevity of the reaction in different environments. If the pH is higher than 7, then the reaction rate will increase due to the ample amount of hydrogen ions in the hydrogen peroxide. However the pH level cannot be higher than 10 or else there will be too many hydrogen atoms in the peroxide for the enzyme to be able to deconstruct them. If the temperature is increased, then the reaction rate will increase due to the ample amount of energy and movement in the hydrogen peroxide and enzyme.