Laboratory Report on Enzyme Activity

The objective of this lab was to determine the best pH level to increase enzyme activity. As this objective was met, it was discovered that water (pH level 7) was the best for percent absorbance. The hypothesis for this experiment was, “If peroxidase is an enzyme and therefore contains certain pH tolerances, then when placed in solution with pH levels of three, seven, and ten and the reaction is measured by a colorimeter, then water will be the optimal solution for maximum reaction rate.” As seen in the tables and graphs, the data supported the hypothesis due to the fact that most enzymes have an optimal pH of 4-9. Although it was expected for water to be the optimal pH, it was also assumed that more drastic activity would happen with the other pH’s. For example, it was thought that it would still have some noticeable increase; however, when looking at the data and the graph, the numbers oscillate with no noticeable positive or negative trend. Tables 1 and 2 show that the absorbance rate in comparison to the absorbance rate in Table 3 are significantly smaller. Furthermore, after calculating the processed data for reaction rates and looking at the graph, pH 7 water had the highest rate. This experiment gives a good insight for future references about enzymes and the effect of environmental factors and its functions. By completing this experiment, knowledge collected about optimal pH in enzymes will help

Enzymes are biological catalysts that increase the rate of a reaction without being chemically changed. Enzymes are globular proteins that contain an active site. A specific substrate binds to the active site of the enzyme chemically and structurally (4). Enzymes also increase the rate of a reaction by decreasing the activation energy for that reaction which is the minimum energy required for the reaction to take place (3). Multiple factors affect the activity of an enzyme (1). These factors include the pH and the temperature of the solution (1). Most enzymes have a preferred temperature and pH range (2). The preferred temperature for catalase falls between the ranges of thirty five to fifty degrees Celsius (4). Temperatures that are too high denature the enzyme and halt the enzyme’s activity (2). Catalase denatures starts to denature at fifty five degrees Celsius (2). Reactions in the human body produce hydrogen peroxide as a product (1). Since hydrogen peroxide is poisonous to the human body, catalase catalyzes hydrogen peroxide into water and oxygen (2 H2O2 → 2 H2O + O2) (1). According to the collision theory, a reaction can only occur if particles collide with sufficient energy to overcome the activation energy and with correct geometrical orientation (3). Increasing temperature increases the kinetic energy of the particles which means that an increase in temperature will increase the speed of the hydrogen peroxide and the catalase molecules which

4. Describe what is measured as an indicator of sucrase activity and why this is an indicator of sucrase activity.

About pH: If the pH level is less than 5, then the speed of the enzyme reaction will be slower.

To determine the kinetic parameters, Vmax and Km, of the alkaline phosphatase enzyme through the determination of the optimum pH and temperature.

Enzymes speed up chemical reactions enabling more products to be formed within a shorter span of time. Enzymes are fragile and easily disrupted by heat or other mild treatment. Studying the effect of temperature and substrate concentration on enzyme concentration allows better understanding of optimum conditions which enzymes can function. An example of an enzyme catalyzed reaction is enzymatic hydrolysis of an artificial substrate, o-Nitrophenylgalactoside (ONPG) used in place of lactose. Upon hydrolysis by B-galactosidase, a yellow colored compound o-Nitrophenol (ONP) is formed. By using a spectrophotometer to measure absorbance at 420 nm, the rate of enzyme activity after all reactions have come to a stop can be

Enzymes are biological catalysts that speed up a chemical reactions. They do this by decreasing the activation energy(the energy needed to start the reaction) of a chemical reaction. The enzyme present in our saliva is called Amylase. Amylase increases the rate of reaction by decreasing the activation energy needed to hydrolyse the starch molecules. These enzymes have a secondary and tertiary structure and this could be affected by increases and decreases in temperature beyond the optimum temperature of the enzyme to work in. Mostly enzymes are highly affected any changes in temperature beyond the enzymes optimum. There are too

Look at your graph for Part B, how does temperature affect enzyme activity? The colder the temperature the greater the reaction.

To catalyze a reaction, an enzyme will grab on (bind) to one or more reactant molecules. In this experiment we examined how increasing the volume of the extract added to the reaction would affect the rate of the reaction. The enzyme used was horseradish peroxidase which helps catalyze hydrogen peroxide. Using different pH levels, the absorbance rate of the reaction was measured to see at which condition the enzyme worked best. The rates of absorption were calculated using a spectrophotometer in 20 second intervals up to 120 seconds. It was hypothesized that the optimal pH for the enzyme was pH 7 while the 1.0 ml peroxidase would have the best reaction rate. At the end of the experiment the results prove the hypothesis to be incorrect.

Figure 1 shows that the optimum temperature for catalase to catalyze hydrogen peroxide is around room temperature (30℃) as it has a very fast reaction rate (5). The overall trend is that temperatures that differ from 30℃, will decrease the reaction rate.

Biochemical tests are the tests used for the identification of bacterial species based on the differences in the biochemical activities of different bacteria. Bacterial physiology differs from one species to the other. These differences in carbohydrate metabolism, protein metabolism, fat metabolism, production of certain enzymes and ability to utilize a particular compound help them to be identified by the biochemical tests. Gram’s stain was originally devised by histologist Hans Christian Gram in 1884. Gram-positive bacteria stain purple, while Gram-negative bacteria stain pink when subjected to Gram staining. Approximately 60-90% of the Gram-positive bacterial cell wall is made up of peptidoglycan and interwoven teichoic acid, while only

Background: Enzymes are catalysts which help reactions inside of organisms such as cells. Many different types of enzymes are used to catalyze different types of reactions. Enzymes are able to catalyze reactions that normally wouldn’t be possible under the specific circumstances in the cell such as the pressure or temperature of the cell. The way an enzyme works is it binds with the active site of a substrate and creates an enzyme substrate complex. The enzyme then breaks apart the bonds in a substrate and then leaves unchanged after the reaction. The enzyme this lab will be looking at today is the catalase enzyme. Catalase is found among almost all living organisms. The catalase which this lab uses will be a 1% catalase solution but an example of natural catalase is the catalase found in the liver. Catalase reacts with hydrogen peroxide, binding onto it and breaking it down into the less toxic water and oxygen. The equation for this reaction is the following:

ABSTRACT: The purpose of the experiments for week 5 and week 6 support each other in the further understanding of enzyme reactions. During week 5, the effects of a substrate and enzyme concentration on enzyme reaction rate was observed. Week 6, the effects of temperature and inhibitor on a reaction rate were monitored. For testing the effects of concentrations, we needed to use the table that was used in week 3, Cells. The 3 concentrations of enzymes were 0.5 ml, 1.0 ml, and 2.0 ml of turnip extract, while the substrate consisted of 0.1ml, 0.2 ml, and 0.4 ml of hydrogen peroxide. In a separate tube, the control was made up of turnip extract and guaiacol, known as the color reagent. This was recorded the absorbance every 20 seconds for 3 minutes.

Usually, the microbial enzymes have various potential uses in industries and medicine. The microbial enzymes are also more reliable than plant and animal enzymes as they are more stable and active. Also the microorganisms demonstrate an alternative source of enzymes because they can be cultured in large quantities in a short time by fermentation and owing to their biochemical diversity and susceptibility to gene manipulation. Industries are looking for new microbial strains in order to produce different enzymes to fulfil the current enzyme

Bio Chem lab Report 04 Enzyme Biochemistry Group Member: Chan Man Jeun Duncan (16002621) Law Sze Man (16000478) Introduction Enzyme is a protein base structure substance in our body. It works at a biocatalyst that will catalyzing the chemical reaction, which helps to speed up the chemical reaction. Enzyme could only function in specific shape, and the shape of enzyme is depending on the environment, therefore it is hard for an enzyme to function well in an extreme environment. The aim of this experiment is to see can the enzyme functions normally in different environment(pH, temperature and salt concentration) via using starch solution, amylase from saliva, 0.5M HCl solution, 0.5M NaOH solution and NaCl solution, and using iodine solution