Enzyme Catalysis And Its Effect On The Reaction Rate Of An Enzyme

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

Used to see if the temperature of the water is at 37oc – 40oc and if

The temperature can have a major impact on an enzyme. According to Campbell Biology author Reece etc. 2011 “The enzyme reaction will increase as the temperature increase with the increasing temperature….substrates collide with active sites more frequently when the molecules move rapidly.”(Reece etc 2011) Every enzyme hits its optimal temperature the reaction will be at its highest point.(Reece etc. 2011) When the

Enzyme catalysis is dependant upon factors such as concentration of enzyme and substrate, temperature and pH. These factors determine the rate of reaction, and an increase in temperature or pH above the optimum will

[An active site can be altered by a non-competitive enzyme which encircles the enzyme and alters the shape of the active site which could be very dangerous.]

Enzymes are biological catalysts, which speed up the rate of reaction without being used up during the reaction, which take place in living organisms. They do this by lowering the activation energy. The activation energy is the energy needed to start the reaction.

Effect of pH on Enzyme Activity. 1. Dependent Variable. amount of product (glucose and fructose) produced 2. Independent Variable. pH 3. Controlled Variables. temperature; amount of substrate (sucrose) present; sucrase + sucrose incubation time

My graph shows there is an almost perfect positive correlation between the hydrogen peroxide concentration and the rate of the catalase enzyme reaction, with a correlation coefficient of 0.99. The rate of reaction at 1% concentration was 0.46cm3 oxygen produced per minute and the lowest recorded rate. For 3% was 1.33cm3 per minute, and for 6% was 2.17cm3 per minute and was the highest recorded rate. The

Question: How does changing enzyme concentration or temperature affect the reaction time of enzyme activity?

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

3. How is free energy useful for understanding enzyme function? Free energy is useful for understanding enzyme function because it is required to initiate the conversion of the reaction to product. While enzymes do not change the equilibrium of the reaction or the energy difference between the product and reactant, they do, however, decrease the activation energy and facilitate the formation of the transition state, speeding up the reaction.

As seen on table 1, the hypothesis in the introduction of this lab has been supported by the procedures. As the temperature varied from catalases optimal of 37° C, the reaction rate of catalase decreased. 37°C had the highest reaction rate of the three, at 3, while 4°C had the middle rate of reaction at 2.5, and 100° C had the lowest reaction rate of 0.5.

Enzyme concentration has a direct impact on the rate of reaction. When looking at graph 1 it is easy to see a linear relationship between the rate of formation of NADH and the concentration of the enzyme. As enzyme concentration increases the rate of reaction increases because substrates are more likely to collide with available enzymes. Le Chatelier's principle supports this as adding more enzyme will cause the reaction to shift more towards the enzyme substrate complex which will result in the rate of the reaction increasing. Based on this data we were able to choose the best enzyme dilution factor for the remaining experiments.

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.

A chemical reaction requires that bonds in the reactants be broken. The initial energy that must be absorbed in order to break the bonds of the reactant molecule is called the energy of activation. Enzymes work by lowering the energy of activation. For example,