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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Enhanced green fluorescent protein (EGFP) was originally isolated from a bioluminescent jellyfish called Aequorea victoria. As suggested by the name, this protein fluoresces green when exposed to light in the ultraviolet range. The ultimate goal of the following experiment was to successfully create a pET41a(+)/EGFP recombinant plasmid that was transformed into live E. coli cells. The success of this transformation could be evaluated based on whether EGFP’s fluorescence properties were displayed by the colony in question. The protein’s fluorescence properties “triggered the widespread and growing use of GFP as a reporter for gene expression and protein localization in a broad variety of organisms” (Ormo, et. al., 1996). Although EGFP and GFP differ for a few amino acids that make EGFP’s fluorescence mildly stronger, the basic principle that such a protein allows for the evaluation of transformation success remains intact.
Moreover, the class average curve shows a similar trend, as the curve flattens, at 70% but with an enzyme activity of 5.3 x10-3 seconds. This indicates that even though the saturation point is the same it was considerably lower than our results, which could indicate sources of systematic error in the design of the practical.
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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.
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
The shape of the molecules is changing and so the enzyme molecules can no longer fit into the gaps in the substrate that they need to and therefore the enzymes have de – natured and can no longer function as they are supposed to and cannot do their job correctly. Changing the temperature: Five different temperatures could be investigated. Water baths were used to maintain a constant temperature. Water baths were set up at 40 degrees, 60 degrees and 80 degrees (Celsius). Room temperature investigations were also carried out (20 degrees).
An example would be the firefly squid, which has thousands of photophores, or organs that emit a deep blue
The enzymes have active sites on their surfaces to allow the binding of a substrate through the help of coenzymes to form enzyme-substrate complex. The chemical reaction thus converts the substrate to a new product then released and the catalytic cycle proceeds.
The structure of the enzyme is mainly dependent on the active site and variable groups. Extreme temperatures or extreme pHs can alter the structure of an enzyme. Enzymes function to lower the activation energy to break the bonds. They achieve this by putting stress and pressure on the bonds or creating a microenvironment for the substrate. A change in the temperature or a fluctuation in pH can alter...
The white (w) eye color gene is located on the X chromosome at 1.5 genetic map units (1). The mutation is also recessive, meaning that each fly has different copies of the gene if they are either male or female (2). In wild-type Drosophila, the brick red color is visible due to the combination of two pigments, brown and scarlet. The synthesis of drosopterin for bright red pigments is controlled by the (bw+) gene and the synthesis of ommochromes for brown pigments is controlled by the (st+) gene (7). Therefore, there are two pigment synthesis pathways that must be working in order for the flies to express the brick red eye color. In addition, transport proteins are responsible for transporting both pigments into the eye in order to express the color (8). Thus, both the pathways responsible for the synthesis of brown and red pigments must work properly as well as the genes that encode for transport proteins. Despite having white eyes, Drosophila flies with this mutation still experience normal eyesight
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 essential biological catalysts in the human body that biochemical reaction. Catalysts work by lowering the activation energy, the minimum energy required for a reaction to occur, which increases the rate of the reaction (Burdge, 2014). Enzymes catalyze reactions by applying pressure onto the bonds of the substrate which lowers the activation energy and breaks these bonds to form products. Even though some enzymes have been found to be non-proteins, most of them are globular proteins which possess an active site where the substrate attaches itself (Raven, 114). The two models that describe the manner in which substrates attach to enzymes are the lock-and-key model and the induced fit model. The lock-and-key model is used to explain an enzyme that fits to only one type of substrate. It is like a lock and key in the sense that only one lock can fit into a key, therefore, only one substrate can fit into the active site of an enzyme that follows this model. On the other hand, an enzyme that follows the induced fit model slightly changes its shape in order for the substrate to...
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.
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
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?