The Effect of Different Concentrations of a Substrate On an Enzyme
Introduction:
Enzymes are biological catalysts. They are generally large proteins
made up of several hundred amino acids. Enzymes catalyze thousands of
chemical reactions that occur in living cells. Enzymes are highly
specific so each one speeds up only one particular chemical reaction.
Many kinds of enzymes are found in each cell but because they are used
over and over there may be only a small amount of each enzyme
present.
In this lab activity, you will study the enzyme catalase and its
substrate hydrogen peroxide. Catalase accelerates the breakdown of
hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2). The
chemical equation for this reaction is:
2 H2O2 ----Catalase-------> 2H2O + O2
Catalase is found in both plant and animal tissues. It is especially
abundant in plant storage organs such as potatoes and the fleshy parts
of fruits. Catalase is extremely important in cells because it
prevents the accumulation of hydrogen peroxide. Hydrogen peroxide is
a strong oxidizing agent, which tends to disrupt the delicate balance
of cell chemistry. If too much hydrogen peroxide accumulates, it will
kill the cell.
Several factors affect the action of enzymes: salt concentration, pH,
temperature, enzyme poisons, radiation, the concentration of enzymes,
and the concentration of the substrate.
This lab deals only with how an enzyme is affected by different
concentrations of substrate - specifically, what effect will different
concentrations of a substrate (H2O2) have on an enzyme (catalase in
potato juice).
Objectives:
1. You will determine how different concentrations of a substrate
affect the enzymatic activity of the
enzyme catalase.
2. You will construct and interpret a graph of the data collected.
Safety Notes:
1. Hydrogen peroxide can damage your clothes. Rinse any spills with
water immediately.
2. Keep hydrogen peroxide out of your eyes.
Living organisms undergo chemical reactions with the help of unique proteins known as enzymes. Enzymes significantly assist in these processes by accelerating the rate of reaction in order to maintain life in the organism. Without enzymes, an organism would not be able to survive as long, because its chemical reactions would be too slow to prolong life. The properties and functions of enzymes during chemical reactions can help analyze the activity of the specific enzyme catalase, which can be found in bovine liver and yeast. Our hypothesis regarding enzyme activity is that the aspects of biology and environmental factors contribute to the different enzyme activities between bovine liver and yeast.
Catalase is a common enzyme that is produced in all living organisms. All living organisms are made up of cells and within the cells, enzymes function to increase the rate of chemical reactions. Enzymes function to create the same reactions using a lower amount of energy. The reactions of catalase play an important role to life, for example, it breaks down hydrogen peroxide into oxygen and water. Our group developed an experiment to test the rate of reaction of catalase in whole carrots and pinto beans with various concentrations of hydrogen peroxide. Almost all enzymes are proteins and proteins are made up of amino acids. The areas within an enzyme speed up the chemical reactions which are known as the active sites, and are also where the
The results of this experiment showed a specific pattern. As the temperature increased, the absorbance recorded by the spectrophotometer increased indicating that the activity of peroxidase enzyme has increased.At 4C the absorbance was low indicating a low peroxidase activity or reaction rate. At 23C the absorbance increased indicating an increase in peroxidase activity. At 32C the absorbance reached its maximum indicating that peroxidase activity reached its highest value and so 32 C could be considered as the optimum temperature of peroxidase enzyme. Yet as the temperature increased up to 60C, the absorbance decreased greatly indicating that peroxidase activity has decreased. This happened because at low temperature such as 4 C the kinetic energy of both enzyme and substrate molecules was low so they moved very slowly, collided less frequently and formed less enzyme-substrate complexes and so little or no products. Yet, at 23 C, as the temperature increased, enzyme and substrate molecules
Catecholase is an enzyme formed by catechol and oxygen used to interlock oxygen at relative settings, and it is present in plants and crustaceans (Sanyal et. al, 2014). For example, in most fruits and vegetables, the bruised or exposed area of the pant becomes brown due to the reaction of catechol becoming oxidized and oxygen becoming reduced by gaining hydrogen to form water, which then creates a chain that is is the structural backbone of dark melanoid pigments (Helms et al., 1998). However, not all fruits and plants darken at the same rate. This leads to question the enzymatic strength of catecholase and how nearby surroundings affect its activity. The catecholase enzyme has an optimal temperature of approximately 40°C (Helms et al., 1998). Anything above that level would denature the tertiary or primary structure of the protein and cause it to be inoperable. At low temperatures, enzymes have a slower catalyzing rate. Enzymes also function under optimal pH level or else they will also denature, so an average quantity of ions, not too high or low, present within a solution could determine the efficiency of an enzyme (Helms et al., 1998). Also, if more enzymes were added to the concentration, the solution would have a more active sites available for substrates and allow the reaction rate to increase if excess substrate is present (Helms et al., 1998). However, if more
It is important however to note that the NH4 and K ions are still in
Abstract: Enzymes are catalysts therefore we can state that they work to start a reaction or speed it up. The chemical transformed due to the enzyme (catalase) is known as the substrate. In this lab the chemical used was hydrogen peroxide because it can be broken down by catalase. The substrate in this lab would be hydrogen peroxide and the enzymes used will be catalase which is found in both potatoes and liver. This substrate will fill the active sites on the enzyme and the reaction will vary based on the concentration of both and the different factors in the experiment. Students placed either liver or potatoes in test tubes with the substrate and observed them at different temperatures as well as with different concentrations of the substrate. Upon reviewing observations, it can be concluded that liver contains the greater amount of catalase as its rates of reaction were greater than that of the potato.
Investigating the Effect of Substrate Concentration on Catalase Reaction. Planning -Aim : The aim of the experiment is to examine how the concentration of the substrate (Hydrogen Peroxide, H2O2) affects the rate of reaction. the enzyme (catalase).
Test tube A will have a piece of potato which is this size. Test tube
The Effect of Surface Area on the Rate of Reaction Between Catalase from a Potato and Hydrogen Peroxide
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.
Investigating a Factor that Affects Enzyme Activity Planning -------- Aim --- To investigate a factor which will affect the activity of catalase, whilst keeping all variables constant. Possible Independent Variables ------------------------------ Here are a number of possible independent variables that could be changed in the experiment: Independent variable Continuous/Discontinuous Easy to measure?
In this lab, it was determined how the rate of an enzyme-catalyzed reaction is affected by physical factors such as enzyme concentration, temperature, and substrate concentration affect. The question of what factors influence enzyme activity can be answered by the results of peroxidase activity and its relation to temperature and whether or not hydroxylamine causes a reaction change with enzyme activity. An enzyme is a protein produced by a living organism that serves as a biological catalyst. A catalyst is a substance that speeds up the rate of a chemical reaction and does so by lowering the activation energy of a reaction. With that energy reactants are brought together so that products can be formed.
Enzymes are protein molecules that are made by organisms to catalyze reactions. Typically, enzymes speeds up the rate of the reaction within cells. Enzymes are primarily important to living organisms because it helps with metabolism and the digestive system. For example, enzymes can break larger molecules into smaller molecules to help the body absorb the smaller pieces faster. In addition, some enzyme molecules bind molecules together. However, the initial purpose of the enzyme is to speed up reactions for a certain reason because they are “highly selective catalysts” (Castro J. 2014). In other words, an enzyme is a catalyst, which is a substance that increases the rate of a reaction without undergoing changes. Moreover, enzymes work with
How the Concentration of the Substrate Affects the Reaction in the Catalase Inside Potato Cells
The Enzyme Concentration and The Volume of Juice As the enzyme concentration increases so too does the volume of juice. This is because as the concentration of enzyme molecules increase there is more chance of a collision with an apple substrate molecule. If the chance of a collision is increased then the number of collisions will increase resulting in a higher rate of reaction. The enzyme combines with the substrate to form an enzyme-substrate complex.