Gluconeogenesis: Difference between revisions
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Gluconeogenesis is the production of glucose mostly from lactate, which the end product of glycolysis. Other precursors molecules such as glycerol and amino acids, repsectively derived from fat and protein catabolism. | Gluconeogenesis is the production of [[Glucose|glucose]] mostly from lactate, which the end product of [[Glycolysis|glycolysis]]. Other precursors molecules such as [[Glycerol|glycerol]] and [[amino acids|amino acids]], repsectively derived from [[Fat|fat]] and [[Protein|protein]] [[Catabolism|catabolism]]. | ||
The primary site of gluconeogenesis is located in the liver. It is therefore responsible for glucose homeostasis by transporting glucose throughout the systems via the bloodstream. | The primary site of gluconeogenesis is located in the [[Liver|liver]]. It is therefore responsible for [[Glucose|glucose]] homeostasis by transporting glucose throughout the systems via the bloodstream.[[|]]<br>Essentially, gluconeogenesis(glucose synthesis) in a sense may seems to be the reverse reaction of [[Glycolysis|glycolysis]] ([[Glucose|glucose]] breakdown). However, these two reactions are not completely irreversible, due to the "one-way only" steps that are present in the individual biochemical processes, as well as the different catalysing enzymes involved. | ||
The three main enzymes of gluconeogenesis are [[Pyruvate carboxylase|pyruvate carboxylase]], [[Phosphoenol-pyruvate carboxykinase|phosphoenol-pyruvate carboxykinase]] and [[Fructose 1, 6-biphosphatase|fructose 1, 6-biphosphatase]]. The first step is the conversion of [[Pyruvate|pyruvate]] into [[Oxaloacetate|oxaloacetate]]. <br>These three steps are all regulated by [[Allosteric control|allosteric control]] and thye are energy-consuming. Gluconeogenesis is inhibited by [[AMP|AMP]] and [[ADP|ADP]]. When the body is in low energy level, pyruvate is required to be transported into CAC to obtain energy. Since [[Pyruvate|pyruvate]] is required for the synthesis of [[Glycogen|glycogen]], low levels of [[Pyruvate|pyruvate]] threfore give a negative feedback to the process of gluconeogenesis. | |||
Furthermore, [[Hormones|hormones]] also play an important role in gluconeogenesis, for instance [[Insulin|insulin]] has an effect of inhibiting gluconeogenesis, on the hard, presence of [[Glucagon|glucagon]] favours the process of [[Glycogen synthesis|glycogen synthesis]]. <br><br><br> <br> | |||
Furthermore, hormones also play an important role in gluconeogenesis, for instance insulin has an effect of inhibiting gluconeogenesis, on the hard, presence of glucagon favours the process of glycogen synthesis. <br><br><br> <br> | |||
Revision as of 11:14, 10 January 2011
Gluconeogenesis is the production of glucose mostly from lactate, which the end product of glycolysis. Other precursors molecules such as glycerol and amino acids, repsectively derived from fat and protein catabolism.
The primary site of gluconeogenesis is located in the liver. It is therefore responsible for glucose homeostasis by transporting glucose throughout the systems via the bloodstream.[[|]]
Essentially, gluconeogenesis(glucose synthesis) in a sense may seems to be the reverse reaction of glycolysis (glucose breakdown). However, these two reactions are not completely irreversible, due to the "one-way only" steps that are present in the individual biochemical processes, as well as the different catalysing enzymes involved.
The three main enzymes of gluconeogenesis are pyruvate carboxylase, phosphoenol-pyruvate carboxykinase and fructose 1, 6-biphosphatase. The first step is the conversion of pyruvate into oxaloacetate.
These three steps are all regulated by allosteric control and thye are energy-consuming. Gluconeogenesis is inhibited by AMP and ADP. When the body is in low energy level, pyruvate is required to be transported into CAC to obtain energy. Since pyruvate is required for the synthesis of glycogen, low levels of pyruvate threfore give a negative feedback to the process of gluconeogenesis.
Furthermore, hormones also play an important role in gluconeogenesis, for instance insulin has an effect of inhibiting gluconeogenesis, on the hard, presence of glucagon favours the process of glycogen synthesis.