Proteins play a fundamental role in the existence of living organisms. They are major contributors of cell structure and mobility, hormonal interaction, information exchange, and, most importantly, regulation of essential reactions. Enzymes are proteins that activate or inhibit the conversion of a substrate to a product. Often, enzymes catalyze reactions that are crucial for biological processes, but a few regulate other aspects of life, such as communication between a species. The enzyme luciferase catalyzes the reaction that allows fireflies to communicate with each other via emission of a yellow-green to yellow-orange colored light (Nakatsu, T. et al., 2006, 372). This reaction is a bioluminescence reaction, where chemical energy is converted into light energy (Branchini, B.R., Magyar, R.A., Murtiashaw, M.H., and Portier, N.C, 2001, 2410). Luciferase stimulates an interesting reaction mechanism that is dependent on the enzyme’s structure and environmental factors, resulting in varying colors of emitted light. Furthermore, luciferase, though mainly found in insects, has practical application in cancer monitoring and research for humans.
The structure of luciferase makes it part of the ‘acyl-adenylate/thioester-forming’ family of enzymes. The distinguishing quality of the family is an enormous N-terminus domain, housing the major portion of the activation site comprised of residues 1-436, and an exponentially smaller C-terminus domain, made up of residues 440-550 (Branchini, B.R., Magyar, R.A., Murtiashaw, M.H., and Portier, N.C, 2001, 2411). The enzyme changes its conformation upon substrate binding; the gap between the N-terminus and C-terminus, also known as the active site, closes to increase the enzyme’s effici...
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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
My results did not completely support my hypothesis, while I was correct about pH, temperature, enzyme concentration and inhibitors I was incorrect about substrate concentration. I originally believed that increasing substrate concentration
Purpose: The purpose of this lab is to explore the different factors which effect enzyme activity and the rates of reaction, such as particle size and temperature.
An example of bioluminescence is a firefly. The production of light in bioluminescent animals is caused by converting chemical energy to light energy (Bioluminescence, 1 of 1). In a firefly, oxygen, luciferin, luciferase (an enzyme), and ATP combine in the light organ in a chemical reaction that creates cold light (Johnson, 42). This bright, blinking light helps the male firefly attract female fireflies as a possible mate. Other examples of bioluminescent organisms are fungi, earthworms, jellyfish, fish, and other sea creatures (Berthold Technologies, 1 of 2).
An enzyme can be defined as a protein that acts as a catalyst in a biological system. It increases the rate of reaction by decreasing the activation energy. The catalytic power and specificity of an enzyme can be altered by the binding of certain molecules. These molecules are referred to as inhibitors. An inhibitor works to prevent the formation, or to cause the breakdown of an enzyme-substrate compound. There are two categories of inhibitors. The first being irreversible inhibitors, and the second being reversible inhibitors. Irreversible inhibitors tend to be more tightly bound, covalently or noncovalently (mostly covalently), to the enzyme than reversible inhibitors, which tend to dissociate more rapidly from the enzyme. Reversible inhibitors can be subdivided into three groups: competitive, uncompetitive, and noncompetitive.
5 test tubes were prepared for dilution respectively to 5 spec tubes that had the inhibitor and water and ready for the enzyme addition. Recordings were done every 60 seconds for 3 minutes. Reaction rate was then calculated after time ended. After having used the inhibitor, the steps were repeated but replace the inhibitor with water as control and experimented for the rates without the inhibitor. Percentages were graphed by the percentage inhibition versus the substrate concentration for the inhibitor. Part 5 of the experiment was to determine the effect of temperature or pH on the reaction rate. In doing so, each group in the lab was designated a particular enzyme that was exposed in different temperatures (Schultz, 2006). The enzymes were exposed before the beginning of the experiment into these different temperatures: boiling, warm (heat), room temperature, cold (ice bath), and frozen. Each enzyme was allowed back to room temperature before adding the buffered catechol with the 1 ml of enzyme into the spec tube (Schultz, 2006). Reaction rate was then determined from the reading. Absorbance versus time was plotted with the determined initial rate of each
Bioluminescence is a mixture of chemicals inside a living thing that glows and generally lives in the twilight zone of the ocean. Bioluminescence consists of, “Two different kinds of light emission, luminescence is when chemical compounds mix together and glow. Incandescence is a filament inside the creature that gets very hot and emits light.” (Wilson, Tracy). Bioluminescence is mostly chemistry and how different chemicals mix together to give off different appearances. Luciferin produces light, while luciferase is a catalyst which often needs a charged ion to activate it. Life in the sea most often use coelenterazine, a type of luciferin. These particular animals live in the deeper parts of the ocean like the twilight zone.
The Vmax values, as determined from the Lineweaver-Burk plot, for the uninhibited, half uninhibited, and inhibited enzymes were, 0.3647, 0.1262, and 0.3087 μmol/min respectively. The non-linear regression V¬max¬ values for the same enzyme were 0.3343 (9.09% error as compared to Lineweaver-Burk plot), 0.1264 (0.16% error), and 0.2694 μmol/min (14.6% error) respectively. The differences in the values are due to the presence of error introduced by a Lineweaver-Burk plot, where data points at higher and lower substrate concentrations are weighed differently (Tymoczko, p.115). This error is the reason why a Michaelis-Menten plot is preferred.
The enzyme assay was repeated in water baths at four temperatures: an ice bath (approximately 4 degrees celsius), room temperature (approximately 23 degree celsius), 32 degree celsius, and 48 degree celsius. Test tube 9 was obtained and labeled 19. The appropriate solutions were added to each test tube. All tubes were preincubated at the appropriate temperature prior to the mixing of tubes. The tubes were then set aside to acclimate for 15 minutes. After the equilibrium was reached and the spectrophotometer was adjusted with the control (tube 1) the pairs 2 & 3, 4, & 5, 6 & 7, and 8, & 9 were mixed one at a time. The absorbance changes at 15 second intervals for 60 seconds for each temperature were
We need enzymes in order to survive, without enzymes some reactions would be too slow to keep you alive. Enzymes help cells communicate with each other to keep things under control in the cell. The purpose of this experiment is to understand the role of enzymes in maintaining life and to be able to identify and explain various factors that affect enzyme functions for example the
Our bodies involve and require many different biochemical reactions, which is achieved through the help of enzymes. Enzymes are proteins in our bodies that act as catalyst as they speed up vital biochemical reactions by reducing the “activation energy” needed to get the reaction going. To sustain the biochemistry of life, enzymes maintain temperature inside our living cells balanced and the concentration of reaction molecules. Enzymes are extremely efficient because they remain remarkably unchanged, therefore have the potential to be used over and over again. They are extremely specific with the reactions they catalyze, like a lock and key and, extremely reactive. The molecule to which enzymes make accelerated changes to is the substrate. The molecule that is present after the enzyme-catalyzed reaction is the product. Most enzymes require specific environmental conditions such as temperature and pH levels to be met in order for them to function properly and efficiently. In the first part of the lab we specifically examined a simple enzyme-catalyzed reaction using catechol (the substrate) which will be catalyzed by the enzyme catecholase and will then result in color change. This familiar color
This is made possible by the use of enzymes. Enzymes essentially work within the cells and their ability determined as a result of their specificity brought about by the shapes from the amino acid sequences (Daniel and Danson 2740).
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 the protein molecules that can rapidly increase the rate of all chemical reactions that are ongoing within our body and cells. They are essential to sustain life and have a great range of functions; these can include aiding digestion and maintaining metabolism.
Enzymes Enzymes are the sparks that start the essential chemical reactions our bodies need to live. They are necessary for digesting food, for stimulating the brain, for providing cellular energy, and for repairing all tissues, organs, and cells. There are three types of enzymes: metabolic enzymes, digestive enzymes, and food enzymes. Metabolic enzymes catalyse, or spark, the reactions within the cells. The body's organs, tissues and cells are run by metabolic enzymes.