G6Pd Deficiency

1. What is the function of the enzyme glucose-6-phosphate dehydrogenase

A cytosolic enzyme that catalyzes the chemical reaction : D-glucose 6-phosphate + NADP+ 6-phospho-D-glucono-1,5-lactone + NADPH + H+

ThIs enzyme is in the pentose phosphate pathway (see image), a metabolic pathway that supplies reducing energy to cells (such aserythrocytes) 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. G6PD reduces nicotinamide adenine dinucleotide phosphate (NADP) to NADPH while oxidizing glucose-6-phosphate.

2. What is the importance of G6PD in red blood cells?

G6PD deficiency occurs when a person is missing or doesn't have enough of an enzyme called glucose-6-phosphate dehydrogenase, which helps red blood cells work properly.

Too little G6PD leads to the destruction of red blood cells, called hemolysis. When this process is actively occurring, it is called a hemolytic episode. The episodes are usually brief, because the body continues to produce new red blood cells, which have normal activity.

3. What is the Pentose Phosphate Pathway

The pentose phosphate pathway (also called the phosphogluconate pathway and the hexose monophosphate shunt) is a process that generates NADPH and pentoses (5-carbon sugars). There are two distinct phases in the pathway. The first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of 5-carbon sugars. This pathway is an alternative to glycolysis. While it does involve oxidation of glucose, its primary role is anabolic rather than catabolic. For most organisms, it takes place in the cytosol; in...