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Action of Enzymes

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Action of enzymes as catalysts in biochemical processes

* Enzymes acts as catalyst and increase the rate of all the chemical reactions. * Enzymes are also described by two properties like all other catalysts. It composed of two main functions. * The first function is that, they increase the rate of chemical reactions by without consumed themselves or undergo any change or alteration in the reaction. . ( Zemitec et,al 2008). * The second function is, they increase reaction rates without changing the chemical equilibrium between the reactants and products. ( Bhagavan et,al 2006). * The reaction between two substrates are catalyzed by enzymes. The enzyme brings a template upon which the two substrates are combined together in the proper position and make them to react each other.
Deficiency in aldolase B and hereditary fructose intolerance * Hereditary fructose intolerance is a condition I which affects a humans ability to digest the fructose sugar. The incidence of hereditary fructose intolerance is 1to 2 in 20000 to 30000 individuals in a year worldwide. .( John .R.H 1996) * Hereditary fructose intolerance can be caused by mutations in the ALDOB gene. The ALDOB gene is responsible for making the aldolase B enzyme. The aldolase B enzyme is primarily seen in the Liver. This helps for the fructose metabolism. This enzyme is responsible for the further step in the metabolism of fructose, which breaks down the molecule fructose-1-phosphate into other molecules called glyceraldehyde and dihydroxyacetone phosphate. * The lack of aldolase B can results in the accumulation of fructose 1 phosphate in the liver. This seems to be toxic and can cause death of liver cells. The short of aldolase B can cause the reduction of dihydroxyacetone phosphate and this will lead to decrease in phosphate level in the body. ( Monique L 2008) * The damage of liver cells and a decrease level of phosphate groups will lead to hypoglycemia and will damage liver.

Specific substrate acted on by aldolase B during the breakdown of fructose * The specific substrate that acts on Aldolase B during the breakdown of fructose is fructose -1 phosphate (F1P). (Lowenstein j.m 1969) * This fructose 1 phosphate is further converted in to DHAP and glyceraldehyde. When the process is finished the product will enter the glycolysis cycle to make ATP or energy that can be used for body functions. * In normal cellular conditions, the primary enzymatic activity of aldolase B is to cleave fructose diphosphate (FDP).” (Roth, 2012)
Role of aldolase B in the breakdown of fructose * The ALDOB gene is responsible for making the aldolase B enzyme. The aldolase B enzyme is primarily seen in the Liver. This helps for the fructose metabolism. This enzyme is responsible for the further step in the metabolism of fructose, which breaks down the molecule fructose-1-phosphate into other molecules called glyceraldehyde and dihydroxyacetone phosphate.( John .R.H 1996) * After glyceraldehyde is added by a phosphate ,i.e. by triose kinase to form G3P, can be used in the glycolytic and gluconeogenic pathway, and can be modified in to glucose or pyruvate. * The enzyme helps the chemical reaction to be speed up with minimum error. It is happen by lock and key process where as enzyme is key and substrate is lock. ( Monique L 2008)
ATP and Cori cycle * The Cori cycle , otherwise called as lactic acid cycle is the metabolic pathway in between the lactic acid produced as a result of glycolysis move to the liver and it is converted in to glucose and then comes back to muscles and made back to lactose. (Nelson 2005) * The lactate is accumulated in the liver instead of keeping it in the muscles. Then makes the second mode of Cori cycle, ie gluconeogenesis will start in the liver. * This reverses the glycolysis and fermentation by first converting lactate into pyruvate and then to glucose. * The part of glycolysis produces two ATP molecules. This is produced by consuming 6 ATP molecules in the glycogenesis part. In this stage each stage is maintained by consuming at least 4 ATP molecules. So the cycle cannot be sustained clearly. * This indicates that the Cori cycle reduces the metabolic efforts of muscles to the liver. (www. Wikipedia.com)
Citric acid cycle * Glycolysis is a metabolic process that pyruvate and hydrogen is formed from glucose and glycogen. The pyruvate is converted into acetyl – coenzyme A. For this process enough oxygen is needed. So if the oxygen is sufficient the acetyl coenzyme A then goes on to Krebs cycle or citric acid cycle. (Lowenstein j.m 1969) * As a result of Krebs cycle or otherwise called as electron transfer chain the ADP is converted in to ATP. For this process also there should be sufficient oxygen is needed. * The process by which by using oxygen the ADP is converted into ATP is called as oxidative phosphorylation. * If there is not sufficient oxygen the production of ATP will be less and as a result lactose will be formed as a byproduct. * Because of this proteins will accumulate and will result into acidosis. ( Monique L2008) * If the enzyme called citrate synthase is unable to perform its function a hypothetical defect can happen and it affects the overall production of ATP. The citric acid cycle cannot be finished if the citrate cycle is affected. The citrate synthase has its own role in creating a COA ,which joint with pyruvate and forms acetyl COA. The acetyl COA initiates the citric acid cycle and produce ATP *
Role of coenzyme Q10 in ATP synthesis
The coenzyme Q10 is fat soluble and this is soluble and movable in the cellular membranes. This plays an important role in Electron Transport chain. The electrons from NADH and succinate moves through the electron transport chain to oxygen and further moved out to water.( Bhagavan et,al 2006). This occurs in the inner cellular membranes. The movement of electrons through the ETC will results in H+ pumping and make a proton gradient crossing the membranes. This will used by ATP synthase to release ATP.
The coenzyme Q10 acts in the role of electron carriers starting from enzyme complex 1 to 2 to 3 during the entire process. The coenzyme Q10 acts in each and every cells to make energy.( Zemitec et,al 2008).
References
John R Holum, 1996, 2nd ed, organic and biological chemistry, von Hoffman press.
Monique Laberge phd,2008, 1st ed, essential chemistry, Chelsea house publications.
Nelson David, 2005, 1st ed, principles of biochemistry, WH freeman company. www. Wikipedia.com? Cori /cycle
Lowenstein J.M, 1969, 1st ed, citric acid cycle, Boston academic publication. Bhagavan et al, 2006, 1st ed, coenzyme Q10, intake and absorption, free radical research.
Zmitek et al, 2008, improving bioavailability of coq10, Agro food IND.

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