HMP shunt in erythrocytes

HMP shunt in erythrocytes is of importance due to the generation of NADPH, which maintains the glutathione (G-SH)  in  the reduced  state by  glutathione reductase, a flavoprotein containing FAD. Glutathione  is a tripeptide (glycine-glutamatk-cysteine), which, in  the reduced state takes part in redox reactions in cells. IQ  this process, two glutathione molecules combine to give the oxidized form (G-S-S-G). The  reduced glutathione then  removes H₂O₂  from  the erythrocytes by  glutathione peroxidase,  an enzyme containing  selenium. This  reaction is  important because  , accuinulation of H₂O₂,  may decrease the  life-span of erythrocytes by  increasing the rate of oxidation of haemoglobin  to methaemoglobin.