All living things have thousands upon thousands of chemical reactions that are constantly occurring simultaneously at such a fast rate within the organism (1). Enzymes are high energy proteins that cause the catalyzation (addition of energy needed for a reaction to take place) of chemical reactions in living organisms (1). The amount of an enzyme present in a solution can be measured in enzyme units (U) which is the amount of activity that it takes to catalyze the conversion of 1 micromole of substrate per minute (2). In this lab, wheat germ was purified to determine the protein concentration and how much acid phosphatase activity is present in each step of the purification process. Acid phosphatase is an enzyme that is needed to catalyze the …show more content…
Assays are used as an indicator of whether or not the purification process is working correctly, or if the proteins have been destroyed in the process (1). The lab consisted of purifying wheat germ by utilizing the enzyme that is already present in the substance itself, acid phosphatase. Acid phosphatase was being separated from the wheat germ using a centrifuge (a machine that spins at high speeds in order to separate substances with different densities in a solution) during each step of the experiment to continuously separate and purify the sample (3). There were three assays in which were used during the experiment. One assay used during the experiment was a Bradford dye reagent, which was a blue dye that was added to samples of the supernatant to display the different concentrations of proteins present in each. Another assay that was used during the lab was the KOH. This reagent was added to different samples of the supernatants than what were used for the Bradford dye. The KOH was used to help stop the reaction that had originally taken place from the addition of the acid phosphatase reagent in step three, but its main use was to distinct the different concentrations of the proteins present in each step of the purification
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 use of multiple test tubes and Parafilm was used for each experiment. Catechol, potato juice, pH 7 phosphate buffer, and stock potato extract 1:1 will be used to conduct the following experiments: temperature effect on enzyme activity, the effect of pH on enzyme action, the effect of enzyme concentration, and the effect of substrate concentration on enzyme activity. For the temperature effect on enzyme activity, three test tube were filled with three ml of pH 7 phosphate buffer and each test tube was labels 1.5 degrees Celsius, 20 °C, and 60 °C. The first test tube was placed in an ice-water bath, the second test tube was left at room temperature, and the third test tube was placed in approximately 60°C of warm water. After filling the test tubes with three ml of the
The practical was carried out to investigate the effect of pH on the reaction of the enzyme acid phosphatase.
Enzymes are types of proteins that work as a substance to help speed up a chemical reaction (Madar & Windelspecht, 104). There are three factors that help enzyme activity increase in speed. The three factors that speed up the activity of enzymes are concentration, an increase in temperature, and a preferred pH environment. Whether or not the reaction continues to move forward is not up to the enzyme, instead the reaction is dependent on a reaction’s free energy. These enzymatic reactions have reactants referred to as substrates. Enzymes do much more than create substrates; enzymes actually work with the substrate in a reaction (Madar &Windelspecht, 106). For reactions in a cell it is
The role of an enzyme is to catalyse reactions within a cell. The enzyme present in a potato (Solanum Tuberosum) is catechol oxidase. In this experiment, the enzyme activity was tested under different temperature and pH conditions. The objective of this experiment was to determine the ideal conditions under which catechol oxidase catalyses reactions. In order to do this, catechol was catalyzed by catechol oxidase into benzoquinone at diverse temperatures and pH values. The enzyme was exposed to its new environment for 5 minutes before the absorbance of the catechol oxidase was measured at 420 nm using a spectrophotometer. The use of a spectrophotometer was crucial for the collection of data in this experiment. When exposed to hot and cold temperatures, some enzymes were found to denature causing the activity to decrease. Similarly, when the pH was too high or low, then the catechol oxidase enzyme experienced a significant decrease in activity. It can be concluded after completing this experiment that the optimal pH for catechol oxidase is 7 and that the prime temperature is 20º C. Due to the fact that the catechol oxidase was only tested under several different temperatures and pH values, it is always possible to get a more precise result by decreasing the increments between the test values. However, our experiment was able to produce accurate results as to the
These results shown from this experiment led us to conclude that enzymes work best at certain pH rates. For this particular enzyme, pH 7 worked best. When compared to high levels of pH, the lower levels worked better. The wrong level of pH can denature enzymes; therefore finding the right level is essential. The independent variable was the amount of pH, and the dependent being the rate of oxygen. The results are reliable as they are reinforced by the fact that enzymes typically work best at neutral pH
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.
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 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].
Stoichiometry is a method scientists use to presume how two or more substances will react together. In order to do so successfully, the reactants are positioned on the left and the products on the right. The most important part of successfully
For this experiment, we have to prepare our phosphorylase which extracted from a potato. We prepared by weighed about 250 grams of peeled potato and cut it into cubes. The extracts then blended with 100mL of 0.1M NaF. After filtered the contents into a clean 250mL centrifuge bottle, we centrifuged it for 3 minutes. Then, separated the supernatant into a centrifuge bottle, which is our phosphorylase preparation. The enzyme assay used in this experiment today is the iodine test. As the iodine reacts with starch, it will form a brown, blue or black precipitate due to the iodine ions forcing into a linear arrangement. The endpoint of the enzyme reaction indicates the presence of starch by using the iodine test to determine. The faster the endpoint is reached, the less active the phosphorylase is.
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).
This experiment tested the effects of pH on enzyme activity and how the concentration of enzyme affects the rate of reaction. Enzymes, biological catalysts, are sensitive to changes that can affect the rate of the chemical reaction. The specific enzyme used in this lab was Catecholase, an enzyme found in the cells of many fruits and vegetables. In the first exercise, the greatest amount of product was produced at a pH of 6, which was the most effective pH on the enzyme. There could definitely be further work done with exercise an increase in the number of variables and a new hypothesis would likely produce a more conclusive experiment. In the second exercise, the most absorbance occurred with the greatest amount of phosphate buffer and greatest amount of potato juice. The null hypothesis was rejected because the results were what was expected, more enzymes led to a faster reaction time which is what was hypothesized from outside reading.
Introduction: An enzyme is a protein-based molecule, which acts as a catalyst (a catalyst is a biological molecule which serves to increase the rate at which a chemical reaction occurs by lowering the activation energy barrier without being consumed). The purpose of this experiment was to determine the properties of acid phosphatase (APase) a wheat-germ based enzyme, whose optimal conditions are as follows: pH of 4.8 and temperature of 37 oC) (acid phosphatases remove phosphate groups from molecules and work best in acidic conditions). Employing such optimums to be the positive controls, a series of experiments with negative controls were conducted.
For the enzyme experiment, I hypothesized that test tube number one would have the greatest amount of product. My lab partners and I believed that number one would have the most significant amount of product because it had the highest mL amount of the potato extract. The potato extract is the enzyme of the investigation being used which is catecholase (Picture 4). The substrate in the investigation is catechol (Picture 6), and the reddish-brown product is called benzoquinone (Figure 2). Enzymes are proteins that help the speeding up of chemical reactions. Enzymes will never destroy unless pH, salt, and temperature negatively affect it. When the enzyme is finished with one substrate, it moves on to another one directly after. According to the lab manual by Pearson (2011), substrates are the reactant molecules that are being changed by the enzyme. It is known that when the substance is an enzyme, it ends in letters “ase.” Substrates and enzymes have a lock and key relationship with one another. The key in the relationship is the substrate, and the lock in the relationship is the enzyme (Cap, 2016). An example of an enzyme and substrate relationship is sucrase and sucrose. The enzyme sucrase positions the sucrose, which is table salt, in a way that it can be broken down into the parts of glucose and fructose (Figure 1). The purpose of this