The reason for this is because; this allows the substrate to bind to the active site, which is known as the ‘lock and key model’. The substrate is the key and active site is the lock. No other key will fit into the lock. There are many factors that affect the rate of enzyme activity in the liver, namely, Ph level, and substrate concentration. I chose to do an experiment on ‘How temperature can affect the rate of enzyme activity in the liver?’ Temperature affects the “speeds of the molecules, the activation energy of the catalytic reaction and the thermal stability of the enzyme and substrate.” (2) At different levels of temperature the affects on the enzyme in the liver varies.
Investigation of the effect of Substrate concentration on Catalase activity Research Question: To investigate enzyme kinetics, using catalase enzyme from the yeast extract. Background Information: Enzymes are proteins which catalyze reactions that take place in the body or they increase the rate of the biological reactions. In an enzyme catalyzed reaction, the substrate binds to the active site and forms the enzyme-substrate complex with the enzyme. The enzyme breaks the bonds present in the substrate; the final product of this reaction leaves the enzyme which remains unchanged after the reaction. Catalase is a substance which is produced by the liver to break down hydrogen peroxide.
Various enzymes have unique shape and chemical composition that creates a site, called and active site. This is to allow connection between the enzyme and other molecules called substrates. The shape and chemical makeup of the active site provides an area for part of the substrate to connect with the enzyme. (Farabee, 2010) Part of the active site holds the substrate and part catalyzes the reaction. Some enzymes act on one substrate only, while other enzymes act on a family of related molecules.
Hydrogen Peroxide at high concentrations can be lethal. Catalase is there to help with the processes of breaking it down to assure that this doesn’t happen. The purpose of this lab was to help us understand what happens when an enzyme works with a substrate to make the reaction faster. It was to help show us what the effects of pH and temperature on the enzyme’s reaction. My hypothesis for the experiment was that the optimum temperature for catalase to function is 98.6o F because this is the optimum temperature for the human body.
Enzymes are proteins that are used to speed up these reactions without being consumed by them. The activity of these enzymes can be altered by changing their environments, such as enzyme specificity (speed only a reaction that contains their substrate), increasing and decreasing temperature, concentration level, or adjusting the pH level. Catalase is a catalyst that digests potent hydrogen peroxide and converts it into H2O and O. It is due to this hydrogen peroxide digesting ability that we used catalase in this experiment. To record the role that environment plays in the reaction of an enzyme, we exposed the enzyme to various changes in temperature, concentration, and pH.
Enzyme has an active site in a specific shape because of its tertiary structure. Enzyme works for binding with substance of a specific shape that fits in it and break down the substance. Enzymes denature due to various factors. The temperature, PH level, and the concentration of the substance influence enzyme activities. When these factors vary, enzymes may change in shape so it will not be able to bond to the specific substance anymore.
This is where the reactions occurs. From there the enzyme breaks the bond in the substrate and the enzyme can continue to repeat the process. Catalase is an enzyme found in almost all living organisms. In the human body it is an enzyme that is produced by our liver to break down hydrogen peroxide into water and oxygen. Even though hydrogen peroxide is naturally produced by our body as a byproduct of our metabolic process, it is very toxic to our body.
The enzyme of this experiment was the yeast Peroxidase and the substrate of the experiment was hydrogen peroxide which was diluted by water. Hydrogen peroxide is toxis to most living organisms. Many organisms are capable of enzymatically destroying the hydrogen peroxide before it can do much damage. Hydrogen peroxide can be converted to oxygen and water (Masterman, David, and Kelly Redding). In the experiment, the rate of enzyme activity under various conditions such as different enzyme concentrations, pH values, and temperatures will be measured.
Enzymes, as a subclass of catalysts, are very specific in nature. Each enzyme can act to catalyze only very select chemical reactions and only with very select substances. An enzyme has been described as a "key" which can "unlock" complex compounds. An enzyme, as the key, must have a certain structure or multi-dimensional shape that matches a specific section of the "substrate" (a substrate is the compound or substance which undergoes the change). Once these two components come together, certain chemical bonds within the substrate molecule change much as a lock is released, and just like the key in this illustration, the enzyme is free to execute its duty once again.
Digestive enzymes are hydrolytic enzymes. Their substances, or the molecules on which they act are organic food molecules which they breakdown by adding water to the molecular bonds, thus cleaving the bonds between the subunits or monomers. Digestive enzymes can function outside the body cells; their activity can be studied by test tubes (Marieb and Mitchell 2010). This experiment attempts to re-create the breakdown process that is normally done via digestion with Iodine as a vital component. It can be expected that once amylase reacts with the starch, maltose will then be broken down and less starch will be visible and more sugar will be apparent thus causing the solution mixed with iodine to become lighter and lighter.