Question

What is the location of pentose phosphate pathway to take place?​

Answer 1

Answer:

The HMS generates NADPH for reductive biosynthesis of lipids, and ribose for nucleotide and nucleic acid biosynthesis. The HMS has both nonreversible oxidative and reversible nonoxidative phases. Muscle tissue is deficient in glucose 6-phosphate dehydrogenase, the rate-limiting enzyme in the oxidative phase of the HMS. Liver, adipose, and endocrine tissues possess an active HMS, as does lactating mammary tissue and mature erythrocytes. Thiamin deficiency affects the nonoxidative portion of the HMS. Sedoheptulose 7-phosphate and erythrose 4-phosphate are intermediates in the HMS. In order to completely oxidize glucose in the HMS, Gl-3-P must be converted to Glc-6-P, which involves enzymes of the glycolytic pathway working in the reverse direction.

Hemolytic Anemias

Hexose Monophosphate Shunt (Pentose Phosphate Pathway)

In the HMP shunt (see Fig. 164-3), glucose-6-phosphate undergoes oxidation followed by a series of reactions to yield fructose-6-phosphate and glyceraldehyde-3-phosphate, intermediates in the glycolytic pathway. The HMP shunt is the primary source of erythrocyte NADPH, with 2 moles of NADPH produced for each mole of glucose metabolized. NADPH is required for the reduction of oxidized glutathione and some protein sulfhydryl groups.

Mature erythrocytes synthesize large amounts of reduced glutathione (GSH). GSH protects erythrocytes from oxidants, including hydrogen peroxide (H2O2), superoxide anions (O2−), and hydroxyl radicals (OH), which are produced as byproducts of the oxidation of heme by oxygen. Oxidants are also produced by activated phagocytes (e.g., during infection) and by erythrocytes after exposure to certain agents. When oxidants accumulate, they damage cellular proteins and lipids. Detoxification of H2O2 is significantly enhanced by glutathione peroxidase. GSH is converted to oxidized glutathione (GSSG) and to mixed disulfides with protein thiols. GSH levels are restored by glutathione reductase. In this process,

ʜᴏᴘᴇ ɪᴛ ʜᴇʟᴘs ᴜʜʜ✌️