Glucose-6-phosphate dehydrogenase

__NOTOC__Glucose-6-phosphate dehydrogenase (G6PD) is a cytosolic enzyme in the pentose phosphate pathway (see image), a metabolic pathway that supplies reducing energy to cells (such as erythrocytes) by maintaining the level of the co-enzyme nicotinamide adenine dinucleotide phosphate (NADPH). The NADPH in turn maintains the level of glutathione in these cells that helps protect the red blood cells against oxidative damage. Of greater quantitative importance is the production of NADPH for tissues actively engaged in biosynthesis of fatty acids and/or isoprenoids, such as the liver, mammary glands, adipose tissue, and the adrenal glands.In higher plants, several isoforms of G6PDH have been reported, which are localized in the cytosol, the plastidic stroma, and peroxisomes. [cite journal | first = | last = Corpas FJ et al. | title = A dehydrogenase-mediated recycling system of NADPH in plant peroxisomes | journal = Biochem. J.. | year = 1998 | volume = 330 | issue = 7 | pages = 777–784 | doi = ]

Regulation

Glucose-6-phosphate dehydrogenase is stimulated by its substrate NADP⁺. The usual ratio of NADPH/NADP⁺ in the cytosol of tissues engaged in biosyntheses is about 100/1. Increased utilization of NADPH for fatty acid biosynthesis will dramatically increase the level of NADP⁺, thus stimulating G6PD to produce more NADPH.

G6PD converts glucose-6-phosphate into 6-phosphoglucono-δ-lactone and is the rate-limiting enzyme of the "pentose phosphate pathway".

Glucose-6-phosphate dehydrogenase deficiency is very common worldwide, and cause acute hemolytic anemia in the presence of simple infection, ingestion of fava beans, or reaction with certain medicines, AAA, antibiotics, antipyretics, and antimalarials.

G6PD is remarkable for its genetic diversity. Many variants of G6PD, mostly produced from missense mutations, have been described with wide ranging levels of enzyme activity and associated clinical symptoms. Two transcript variants encoding different isoforms have been found for this gene. [cite web | title = Entrez Gene: G6PD glucose-6-phosphate dehydrogenase| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=2539| accessdate = ]

ee also

* Glucose-6-phosphate dehydrogenase deficiency

Further reading

References

External links

* [http://www.atsdr.cdc.gov/csem/nitrate/no3treatment_management.html#g6pd ATSDR - G6PD Deficiency]

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glucose-6-phosphate dehydrogenase — glucose 6 phosphate dehydrogenase. См. глюкозо 6 фосфатдегидрогеназа. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
glucose-6-phosphate dehydrogenase — An NADP+ enzyme catalyzing the dehydrogenation of d glucose 6 phosphate to 6 phospho d glucono δ lactone, this reaction initiating the pentose shunt. A deficiency of this enzyme can lead to severe hemolytic … Medical dictionary
glucose-6-phosphate dehydrogenase deficiency — n a hereditary metabolic disorder affecting red blood cells that is controlled by a variable gene on the X chromosome, that is characterized by a deficiency of glucose 6 phosphate dehydrogenase conferring marked susceptibility to hemolytic anemia … Medical dictionary
glucose-6-phosphate dehydrogenase deficiency — glucose 6 phosphate dehydrogenase deficiency. См. дефицит глюкозо 6 фосфатдегидрогеназы. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
Glucose-6-phosphate dehydrogenase deficiency — ] The discovery of G6PD deficiency relieved heavily upon the testing of prisoner volunteers at Illinois State Penitentiary, although today such studies cannot be performed. When some prisoners were given the drug primaquine, some developed… … Wikipedia
glucose-6-phosphate dehydrogenase deficiency — ▪ pathology hereditary metabolic defect characterized by an increased tendency of the red blood cells to break and release their hemoglobin (hemolysis), especially after the intake of certain drugs. The condition is caused, as the name… … Universalium
glucose-6-phosphate dehydrogenase deficiency — a hereditary (X linked) condition in which the absence of the enzyme glucose 6 phosphate dehydrogenase (G6PD), which functions in carbohydrate metabolism, results in the breakdown of the red blood cells (haemolysis), usually after exposure to… … Medical dictionary
glucose-6-phosphate dehydrogenase deficiency — a hereditary (X linked) condition in which the absence of the enzyme glucose 6 phosphate dehydrogenase (G6PD), which functions in carbohydrate metabolism, results in the breakdown of the red blood cells (haemolysis), usually after exposure to… … The new mediacal dictionary
glucose-6-phosphate dehydrogenase — noun Date: 1954 an enzyme found especially in red blood cells that dehydrogenates glucose 6 phosphate in a glucose degradation pathway alternative to the Krebs cycle … New Collegiate Dictionary
glucose-6-phosphate dehydrogenase — ¦ ̷ ̷ ˌ ̷ ̷ ¦ ̷ ̷ ¦ ̷ ̷ ˌ ̷ ̷ noun : an enzyme found especially in red blood cells that dehydrogenates glucose phosphate (sense b) in a glucose degradation pathway alternative to the Krebs cycle … Useful english dictionary

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