Case study on Biochemistry - Essay Example

? Biochemistry Task 4 al Affiliation Biochemistry Task 4 Case Explain how enzymes are involved in processes such as the breakdown of fructose. Enzymes play an essential role in the body of organisms. They are protein in nature and acts as a catalyst. This means they speed up chemical reactions in the body. The reaction is part of the cycle and takes place separate at each step. The reaction is incomplete in the absence of enzyme. When the cycle is incomplete, and the product is not formed, the function of the organism cannot properly take place. Without enzymes, the reactions needed for biological processes of the body would take at a slower rate or fail to take place. This is detrimental to the well being of the organism involved. One of the most important enzymatic actions is the breakdown of fructose. This is a simple sugar found in some of foods such as fruit and honey. This is essential as it plays an immense role in supply of energy for the body. However, fructose is not a direct source of energy, but enzymes are required to breakdown fructose into a reliable energy. After eating, catabolism of fructose takes place through fructolyis (National Library of Medicine (NLM), 2011). The process begins with the enzyme fructokinase and produces fructose 1-phosphate as a product (NLM, 2011). The second step is enhanced by aldose B. This enzyme breaks down fructose 1-phosphate into two products: dihydroxyacetone phosphate (DHAP) and glyceraldehydes (NLM, 2011). The products enter the process of glycolysis to ensure the body gets its energy requirement and extra glucose. The absence of enzymes necessary for the breakdown of fructose leads to poor response of the body with repeated ingestion of foods containing fructose (NLM, 2011). Explain how a deficiency in aldolase B can be responsible for hereditary fructose intolerance. Aldolase B plays a significant role in the breakdown of fructose. The absence of the enzyme leads to accumulation of fructose-1-phosphate in the liver cells (NLM, 2011). The accumulation of this substance is toxic, and overtime leads to the death of liver cells (Breakspear Medical Group Ltd, n.d.). Additionally, fructose-1-phosphate fails to release the phosphate group required for repeated ATP production and control of stored sugar (NLM, 2011). Several defects arise due to death of liver cells and low number of phosphate groups. They include hypoglycemia, liver abnormalities, and other forms of hereditary fructose intolerance (NLM, 2011). Provide clearly labeled diagrams to demonstrate: Diagram lock and key models of enzymatic activity. Diagram showing how enzymes function as a lock and key. Diagram the effect of enzymes on activation energy. Discuss the specific substrate acted on by aldolase B. Enzymes are usually specific in nature. They only act to a unique substrate. Aldolase B also demonstrates this uniqueness. Fructose-1-phosphate (F1P) is acted upon by aldolase B. This is the only enzyme that binds on F1P as its substrate. The breakdown leads to the formation of two products that are further metabolized to produce glucose, lactate and uric acid (NLM, 2011). Explain the role of aldolase B in the breakdown of fructose. Aldose B plays an essential role in the breakdown of fructose. The enzyme breaks down fructose-1-phosphate into dihydrooxyacetone phosphate (DHAP) and glyceraldehydes (NLM, 2011). The two products enter the process of glycolisis to answer to body requirements for energy, or increased level of glucose. B. Case two Explain what would happen to the amount of energy available to a cell if the entire Cori cycle occurred and remained within that single cell (i.e., a muscle cell). In the skeletal muscles, there are few mitochondria, and yet they consume a lot of energy. This leads to depletion of oxygen and the muscles are forced to operate without oxygen. The Cori cycle is essential as it links this process with gluconeogenesis in the liver. This means that the lactate produced by the muscle cells travels through the blood into the liver (Myhill, Booth & Howard, 2009). In the liver, it is converted into glucose by a process known as gluconeogenesis (Myhill et al., 2009). This glucose is then transported through blood stream and moves back to the muscles to serve as a fuel for further contraction (Myhill et al., 2009). Through this process, the cycle is complete. However, there are abnormalities that take place, and the cycle remains within a single cell. When this takes place, it means that the ATP required for gluconeogenesis will not be available. Moreover, if the cycle takes place within one cell, the process will not be complete. Consequently, glucose will be consumed, and reused at the expense of ATP and GTP hydrolysis (Myhill et al., 2009). This means that four ATP molecules will be lost in each cycle. Construct a dynamic diagram to show the doctor why the citric acid cycle is central to aerobic metabolism. Explain where in the citric acid cycle a hypothetical defect of an enzyme could occur that prevents an increase in adenosine triphosphate (ATP) production in response to an increased energy need and how the products of the citric acid cycle are converted into ATP. Because of increased energy demand in the body, the ADP is continuously recycled back to ATP. However, this process sometimes fails to take place in the mitochondria, and hence there is inefficient energy in the organism. In the citric acid cycle, a hypothetical defect is likely to take place that prevents generation of ATP. This defect may take place during conversion of isocitrate to ketoglutarate. The conversion is enhanced by Isocitrate dehydrogenase. IDH is usually attached to magnesium ion, but calcium ion can also be bound. If calcium ion is bound to the enzyme, it acts as an inhibitor. The turnover rate is reduced since calcium is larger than magnesium. The defects can also take place during the production of succinate from ketoglutarate and conversion of malic acid to oxalacetic acid. This means the defects would take place in step 4, 6, and ten of the cycle. The citric acid cycle is involved in production of energy in terms of ATP. This occurs through myriad steps. In these steps, high-energy electrons are released to NAD. In one of the step, NAD molecules gains hydrogen ions and transforms into NADH (CliffsNotes.com, n.d.). FAD serves as the electron acceptor, and gains two hydrogen ions to form FADH2 (CliffsNotes.com, n.d.). In the other reactions, enough energy is released to produce a molecule of ATP. This means two molecules of ATP are produced. This is because for each molecule of glucose there are two pyruvic molecules entering the cycle (CliffsNotes.com, n.d.). Explain the role of coenzyme Q10 in ATP synthesize as part of the electron transport chain. Coenzyme Q10 plays an important role in ATP production. It acts as an oxidant in the production of ATP molecule. It is found on the inner part of the mitochondria. It acts as non-protein component in the transfer of electron (Shinde, Patil & Tendolkar, 2005). Moreover, the enzyme helps in the transfer of electron. References Breakspear Medical Group Ltd. (n.d.). Fructose Metabolism. Retrieved from http://www.breakspearmedical.com/files/documents/fructosemetabolism230910_AM_.pdf CliffsNotes.com. (n.d.). Krebs Cycle. Retrieved from http://www.cliffsnotes.com/study_guide/topicArticleId-8741,articleId-8603.html Myhill, S., Booth, N & Howard, J. (2009). “Chronic Fatigue Syndrome and Mitochondrial Dysfunction.” Int J Clin Exp Med, 2, 1-16. National Library of Medicine. (2011). Genetic Home Reference. Retrieved from http://ghr.nlm.nih.gov/gene/ALDOB Shinde, S., Patil, N & Tendolkar, A. (2005). “Coenzyme Q10: A Review of Essential Functions.” The Internet Journal of Nutrition and Wellness, 1(2), 1-5. Read More