Point of Pentose Phosphate Pathway for MCAT?

[Gauss44]

What's the point of the Pentose Phosphate Pathway?

Berkeley Review says to understand why it is important. After reading TBR and internet, I gather that that the "important" aspects are: it produces nadph and takes place in the cytosol. Can you think of anything I missed?

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[image187]

What's the point of the Pentose Phosphate Pathway?

Berkeley Review says to understand why it is important. After reading TBR and internet, I gather that that the "important" aspects are: it produces nadph and takes place in the cytosol. Can you think of anything I missed?

Basically just what you mentioned should be all you need to know for the MCAT. I don't think you'll need to know about specific diseases, but you should maybe look up "G6PD deficiency". Especially for RBCs, the NADH produced in this pathway is important for reducing glutathione, which can in turn reduce outside chemicals that would otherwise put oxidative stress on the cell leading to RBC destruction and anemia. This is a genetic disorder and is sometimes uncovered in people who are susceptible (usually African Americans) when they get certain drugs (malaria prophylaxis, sulfa antibiotics) or eat certain foods (fava beans, hence "favism"). You don't really need to know all this right now but it's interesting I guess you could say, and might help you put the significance of this pathway in context

 

[daney]

From another thread I learned that the pentose-5-phosphate pathway is useful because it produces NADPH, which can be used as an anabolic coenzyme, which can be used in the synthesis of fatty acids and steroids. I had always thought that NADPH was used in plant cells only, but after reading that other forum, I guess it's used in animal cells as well. Someone correct me if I'm wrong about that though.

 

[Czarcasm]

"The main purpose of the pentose phosphate pathway is to regenerate NADPH from NADP+ through an oxidation/ reduction reaction.This reaction is coupled to the formation of ribose 5-phosphate from glucose 6-phosphate.NADPH is used for reductive reactions in anabolism, especially in fatty acid synthesis.In red blood cells, the major role of NADPH is to reduce the disulfide form of glutathione to the sulfhydryl form.The reduced glutathione is pertinent for maintaining the normal structure of red blood cells and for keeping hemoglobin in the ferrous state [Fe(II)].The nonoxidative portion of the pathway creates carbon chain molecules ranging from 3 to 7 carbons.These compounds are intermediates in glycolysis and gluconeogenesis or other biosynthetic processes.The pentose phosphate pathway primarily produces NADPH, ribose 5-phosphate, fructose 6-phosphate, and glyceraldehyde 3-phosphate."

Source: https://www.uic.edu/classes/phar/ph... cases/thiamin/pentose_phosphate_pathway1.htm

 

[orangetea]

honestly all those pathways are going to be given in a passage which will then test you knowledge of various enzymes(phosphotase vs aldolase etc.) OR it will ask you what if this part of the pathway is messed up what will happen to the overall reaction etc. OR it could ask what is oxidized and what is reduced. I would really focus on experimental passages or passages that have these pathways(especially from TBR) 😉