Reactivity glucose-6-phosphate dehydrogenase

Glucose- 6-phosphate dehydrogenase Low or absent enzyme activity in about 10% of African populations. Hemolysis following intake of a number of drugs which have electrophilic reactive metabolites, but also, carriers of this enzyme deficiency have a partial protection from malaria. 

Despite the fact that the formation of these alkoxo and aryloxo vanadates is not favored relative to many other ligated species, they can still have important influences in enzymic systems. It has, for instance, been shown that vanadate in the presence of glucose and glucose-6-phosphate dehydrogenase readily produces gluconic acid, a normal product of glucose-6-phosphate metabolism [3], Similar reactivity has been observed with a number of enzymes that metabolize phosphate compounds [4],... 

Glucose 6-Phosphate Dehydrogenase Plays a Key Role in Protection Against Reactive Oxygen Species... 

Agglutination occurred when a mixture of sulfasalazine and the patient s serum was added to normal erythrocytes treated with the endopeptidase ficin, but there was no reactivity when control serum was used or when sulfasalazine was omitted. Preincubation of sulfasalazine with normal erythrocytes gave negative results on addition of the patient s serum, excluding the possibility of a peniciUin-hke reaction. The patient had normal glucose-6-phosphate dehydrogenase activity and there were no Heinz bodies in a blood smear. 

Glucose-6-phosphate-dehydrogenase (microbial) G-6-PDH 75.56% Non-reactive components... 

PRECAUTIONS AND CONTRAINDICATIONS Melarsoprol should be given to patients only under hospital supervision. The initial dose must be based on clinical assessment rather than body weight. Initiation of therapy during a febrile episode is associated with an increased incidence of reactive encephalopathy. Administration of melarsoprol to leprous patients may precipitate erythema nodosum. The drug is contraindicated during epidemics of influenza. Severe hemolytic reactions have been reported in patients with glucose-6-phosphate dehydrogenase deficiency. 

GLUCOSE 6-PHOSPHATE DEHYDROGENASE PLAYS A KEY ROLE IN PROTECTION AGAINST REACTIVE OXYGEN SPECIES... 

Glucose-6-dehydrogenase is responsible for the first step in a chemical pathway that converts glucose (a type of sugar found in most carbohydrates) to ribose-5-phosphate. Ribose-5-phosphate is an important component of nucleotides, which are the building blocks of DNA and its chemical cousin RNA. This chemical reaction produces a molecule called NADPH, which plays a role in protecting cells from potentially harmful molecules called reactive oxygen species. These molecules are byproducts of normal cellular functions. 

The rate of increase in absorbance at 340 nm due to the formation of NADPH is directly proportional to the CK activity. The CK reaction (reaction [I]) is coupled by the auxiliary hexokinase (EC 2.7.1.1) reaction (reaction [II]) to the glucose-6-phosphate dehydrogenase (EC 1.1.1.49) indicator reaction (reaction [HI]). In these reactions, Mg + and N-acetylcysteine are required as activators to form complexes and a reactivator, respectively. To avoid the inhibition of Ca and adenylate kinase (EC 1.7.4.3) in serum samples, ethylenediaminetetraacetic acid and di(adenosine-5-) pentaphosphate must be present. The activity in serum sample decreases to 98% of initial value after a week in a refrigerator. 

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