Activity of the Enzyme Catalase with Hydrogen Peroxide Background Information: An enzyme (Catalase) is a biological catalyst. It can modify the rate of reaction without being changed itself. Enzymes are also globular proteins that have a three-dimensional specific shape; among with a pocket known as the active site, this has a precise shape to link with the exact substrate. Every enzyme are capable of converting one kind of substrate molecule into one kind of product molecule, which forms the enzyme-substrate complex. There are the minority factors that affect the rate of reaction that include: 1. Temperature: If the temperature was to increase so would the rate of reaction up to a decisive point, as the enzyme will start to denature; this usually occurs at temperatures around 50 to 60 Celsius. The rate of reaction increases because enzymes and substrate have more energy permitting them to move around more rapidly, resulting with more collisions and ensuring the enzyme-substrate complex. When the enzymes denature, the weak bonds that hold the tertiary structure of the enzyme together vibrate at an excessive rate, due to the kinetic energy, that they break as well as altering the shape of the active site to a degree that the substrate can no longer link to it. 2. PH: The formation of the enzyme-substrate complex relies on an exact complementary shape and charge. If there is a change in pH, it will corrupt the charges so that no enzyme-substrate complex can be formed. All enzymes have an optimum pH depending on where they are based, intracellular or extracellular. 3. Substrate concentration: The higher the concentration that faster the rate of reaction, which is until they are working as fast as they possible can. This increase in rate of reaction occurs because the more substrate there is the more chance there is of collisions resulting in the formation of enzyme-substrate complex. If the reaction is working fast as possible, the limiting factor is no longer the substrate but the enzyme concentration.
For example, substrate concentration, enzyme concentration, and temperature could all be factors that affected the chemical reactions in our experiment. The concentration of substrate, in this case, would not have an affect on how the bovine liver catalase and the yeast would react. The reason why is because in both instances, the substrate (hydrogen peroxide) concentration was 1.5%. Therefore, the hydrogen peroxide would saturate the enzyme and produce the maximum rate of the chemical reaction. The other factor that could affect the rate of reaction is enzyme concentration. Evidently, higher concentrations of catalase in the bovine liver produced faster reactions, and the opposite occurs for lower concentrations of catalase. More enzymes in the catalase solution would collide with the hydrogen peroxide substrate. However, the yeast would react slower than the 400 U/mL solution, but faster than the 40 U/mL. Based on this evidence, I would conclude that the yeast has a higher enzyme concentration than 40 U/mL, but lower than 400
As temperature increases, rate of respiration increases, because particles move faster and with more energy, which in turn means more particles collide with enough energy to react. However, as temperature increases, enzyme stability decreases, so at temperatures above the optimum temperature, the rate will decrease, until all the enzymes have been fully denatured and all the active sites have been lost. Enzymes speed up reactions in organisms. Each enzyme works on a specific substance, called its substrate. The diagram below shows an “E” (an enzyme) catalysing the breakdown of “S” (the substrate) into two different products (“P”).
That means the active site and the substrate should be exactly complementary so that the substrate can fit in perfectly. Once they collide, the substrate and. some of the side-chains of the enzyme’s amino acids form a temporary. bond so that the substrate can be held in the active site. They combine to form an enzyme-substrate complex and the enzyme can start.
The [ES] complex can then undergo two different pathways; the complex can dissociate to [E] and [S], at a rate of k or it can shift equilibrium to the left with a rate constant of k2 to form [E] and product [P]1. In this model, the breakdown of the ES complex to yield P is the overall rate-limiting step. Three assumptions of a Michaelis-Menton plot are that a specific [ES] complex in rapid equilibrium between [E] and [S] is a necessary intermediate, the amount of substrate is more than the amount of enzyme so the [S] remains constant, and that this plot follows steady state assumptions. Steady state assumptions states that the intermediate stays the same concentration even if the starting materials and products are constantly changing.2 The rapid equilibrium between enzyme and substrate, and the enzyme-substrate complex yields a mathematical description regarded as the Michaelis-Menton
Sequence of events when the union of a substrate with its enzyme occurs. Preliminary Work: Preliminary work was carried out to find a suitable range to collect data in a way that is appropriate. From the preliminary work I was able to determine suitable intervals of time to collect data. It showed that a volume of amylase below 4cm3 took a very long time to react thus making the experiment takes too long to do. From this I worked out that I should start.
Investigating the Effect of Enzyme Concentration on the Hydrolysis of Starch with Amylase Aim: Investigate the effect of enzyme concentration on the rate of an enzyme-controlled reaction. Using amylase and starch as my example. Introduction: I am investigating the effect of the concentration of the enzyme, amylase on the time taken for the enzyme to fully breakdown the substrate, starch to a sugar solution. The varied variable will be the concentration and all other variables are going to be fixed. The different concentrations will be: 0.5% 0.75% 1.0% 1.5% 2% An enzyme is a class of protein, which acts as a biological catalyst to speed up the rate of reaction with its substrates.
The human body is made of cells, which means that if the cells die, the human dies. Metabolism keeps the cells and thus the body alive and functioning properly and can be divided into two parts: catabolism and anabolism. Catabolism breaks down molecules in order to gain energy while anabolism synthesizes everything that the cells need.
Many factors, for example, pH and temperature affects the way enzymes work by either increasing the rate or determining the type of product produced (). The report, therefore, analyses the effects of the enzyme peroxidase in metabolic reactions and determining its optimum temperature in the reactions.
In this experiment the enzyme peroxidase and the substrate hydrogen peroxide were not mixed initially, instead they were both placed in separate tubes and were incubated at a specific temperature, to prevent hydrogen peroxide from undergoing any reaction with peroxidase until they both acquire the required temperature.
Changes in pH lead to the breaking of the ionic bonds that hold the tertiary structure of the enzyme in place. The enzyme begins to lose. its functional shape, particularly the shape of the active site, such. that the substrate will no longer fit into it, the enzyme is said to. be denatured.
oxygen. Before I do this I must do a preliminary plan to see what my
Jim Clark. (2007). The effect of changing conditions in enzyme catalysis. Retrieved on March 6, 2001, from http://www.chemguide.co.uk/organicprops/aminoacids/enzymes2.html
This hurdle is called the activation energy of the reaction. [IMAGE] By decreasing the activation energy, more substrate is changed to product in a certain amount of time. That is, the enzyme increases the rate of the reaction. [IMAGE] The activity of catalase can be measured by finding the rate of which the oxygen gas is released from the breakdown of Hydrogen Peroxide.
How the Concentration of the Substrate Affects the Reaction in the Catalase Inside Potato Cells
Investigate the Effect of pH on Immobilised Yeast Cells on the Breakdown of Hydrogen Peroxide