Enzymes are catalytic proteins that act to speed up chemical reactions that occur in our bodies and in the bodies of many other organisms by reducing the amount of activation energy required in order for a reaction to occur. Without enzymes, the chemical reactions that take place in all organisms would take place too slowly to keep the organism alive. Since all enzymes are proteins, and protein’s functions are dependent on their structure, enzymes require certain conditions to maintain their perfect structure. The disorder of structure and function of an enzyme is known as denaturation. Certain factors such as temperature, pH, enzyme concentration, and substrate concentration have certain effects on enzyme activity. To investigate the effects of these different conditions, an experimental investigation was set up to test the four different variables and their effect on the enzyme catecholase as it catalyzes catechol, the solute. Results can be seen on Figures A – D.
Figure A shows the data collected when an enzyme’s reaction rate, in other words, absorbance, is measured at varying temperatures. Beginning with an absorbance of 0.549, the enzyme, catecholase, shows an inversely proportional relationship between its absorbance and increasing temperature. Our data shows that as the enzymes are subjected to higher temperatures, the enzymes are rendered inactive and therefore denatured. On the other hand, the enzyme’s optimal potential is shown somewhere between 10˚C and 24˚C.
In this lab or experiment, the aim was to determine the following factors of enzymes: (1) the effects of enzymes concentration the catalytic rate or the rate of the reaction, (2) the effects of pH on a particular enzyme, an enzyme known and referred throughout this experiment as ALP (alkaline phosphate enzyme) and lastly (3) the effects of various temperatures on the reaction or catalytic rate. Throughout the experiment 8 separate cuvettes and tubes are mixed with various solutions (labeled as tables 1,3 & 4 in the apparatus/materials sections of the lab) and tested for the effects of the factors mentioned above (concentration, pH and temperature). The tubes labeled 1-4 are tested for pH with pH paper and by spectrophotometer, cuvettes 1a-4a was tested for concentration and cuvettes labeled 1b-4b was tested for temperature in four different atmospheric conditions (4ºC, 23ºC, 32ºC and 60ºC) to see how the enzyme solution was affected by the various conditions. After carrying out the procedures the results showed that the experiment followed the theory for the most part, which is that all the factors work best at its optimum level. So, the optimum pH that the enzymes reacted at was a pH of 7 (neutral), the optimum temperature that the reactions occurs with the enzymes is a temperature of 4ºC or
The Effects of Varied Temperatures, pH Values, Enzyme Concentrations, and Substrate Concentrations on the Enzymatic Activity of Catecholase
Introduction: Starting out with some background information, I know that enzymes are biological catalysts. The enzyme that I used for this experiment was potato juice. Enzymes make reaction rates go faster. They lower activation energy, making chemical reactions. Temperature has an effect on canola cultivars. The higher temperature decreased stem diameter, but room temperature had thicker stems. So I believe the same will happen for the catechol oxidase; the solution will react faster at room temperature. Other enzymes can also have different effects such as the enzyme in cattle serum. The enzyme lost activity in room temperature. With that being said room temperature can also be detrimental with specific enzymes. Fungus also
These results show how temperature of extreme high, or low affects enzyme activity. The highest rate of enzyme activity occurred at 37 Cº. Anything that was hotter or cold than 37 Cº slowed the reaction rate. As I thought, 100 degrees would denature the enzyme, and that was the case. The data provided shows exactly what temperatures enzymes work best, and worst. The objective was achieved as we discovered the different reaction rates under different temperatures. The results are reliable, as we know enzymes do not work well when under extreme heat or denaturation occurs. What I learned in this experiment was that enzymes don’t work well under cold temperatures because they tend to move slower. My hypothesis did not quite match, because I thought they work best at lower temperatures.
Background and Introduction: Enzymes are proteins that process substrates, which is the chemical molecule that enzymes work on to make products. Enzyme purpose is to increase the rate of activity and speed up chemical reaction in a form of biological catalysts. The enzymes specialize in lowering the activation energy to start the process. Enzymes are very specific in their process, each substrate is designed to fit with a specific substrate and the enzyme and substrate link at the active site. The binding of a substrate to the active site of an enzyme is a very specific interaction. Active sites are clefts or grooves on the surface of an enzyme, usually composed of amino acids from different parts of the polypeptide chain that are brought together in the tertiary structure of the folded protein. Substrates initially bind to the active site by noncovalent interactions, including hydrogen bonds, ionic bonds, and hydrophobic interactions. Once a substrate is bound to the active site of an enzyme, multiple mechanisms can accelerate its conversion to the product of the reaction. But sometimes, these enzymes fail or succeed to increase the rate of action because of various factors that limit the action. These factors can be known as temperature, acidity levels (pH), enzyme and/or substrate concentration, etc. In this experiment, it will be tested how much of an effect
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.
Hold the IKI spray bottle 25 - 30 cm away from the paper towel, and mist with the IKI solution.
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.
As stated in the introduction, three conditions that may affect enzyme activity are salinity, temperature, and pH. In experiment two, we explored how temperature can affect enzymatic activity. Since most enzymes function best at their optimum temperature or room temperature, it was expected that the best reaction is in this environment. The higher the temperature that faster the reaction unless the enzyme is denatured because it is too hot. Similarly, pH and salinity can affect enzyme activity.
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,
Enzymes are a key aspect in our everyday life and are a key to sustaining life. They are biological catalysts that help speed up the rate of reactions. They do this by lowering the activation energy of chemical reactions (Biology Department, 2011).
Abstract: Enzymes, catalytic proteins that at as catalysis which makes the process of chemical reactions more easily. There are two main factors that actually affects enzymes and their functions which are temperature and pH. Throughout this experiment, the study how pH and peroxidase affects each other and the enzyme was made. The recordings of how the enzymes responded when it was exposed to four different pH levels to come up with an optimum pH which was predicted in the hypothesis and the IRV at the end.
Enzymes are high molecular weight molecules and are proteins in nature. Enzymes work as catalysts in biochemical reactions in living organisms. Enzyme Catecholase is found on in plants, animals as well as fungi and is responsible for the darkening of different fruits. In most cases enzymatic activities are influenced by a number of factors, among them is temperature, PH, enzyme concentration as well as substrate concentration (Silverthorn, 2004). In this experiment enzyme catecholase was used to investigate the effects of PH and enzyme concentration on it rate of reaction. A pH buffer was used to control the PH, potato juice was used as the substrate and water was used as a solvent.
Organisms cannot depend solely on spontaneous reactions for the production of materials because they occur slowly and are not responsive to the organism's needs (Martineau, Dean, et al, Laboratory Manual, 43). In order to speed up the reaction process, cells use enzymes as biological catalysts. Enzymes are able to speed up the reaction through lowering activation energy. Additionally, enzymes facilitate reactions without being consumed (manual,43). Each enzyme acts on a specific molecule or set of molecules referred to as the enzyme's substrate and the results of this reaction are called products (manual 43). As a result, enzymes promote a reaction so that substrates are converted into products on a faster pace (manual 43). Most enzymes are proteins whose structure is determined by its sequence of its amino acids. Enzymes are designed to function the best under physiological conditions of PH and temperature. Any change of these variables that change the conformation of the enzyme will destroy or enhance enzyme activity(manual, 43).
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.