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  #1  
Old 10-28-2012
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Biochemistry NADPH Metabolism and Essential Enzymes!

Some humans are unable to generate NADPH from Glucose metabolism but are able to synthesize ribose from fructose 6 po4-. which of the following enzymes are essential.?

a) G6PD
b) glutathione reductase
c) enolase
d) transketolase
e) acotinase
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Old 10-28-2012
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glutathione becomes essential.........BBB
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Old 10-29-2012
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d)transketolase
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Old 10-29-2012
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D) Transketolase; this way one will be able to synthetise ribose bypassing the glucose 6PD enzyme. Transketolase is one of the 4 enzymes that needs thiamine as a cofactor.
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Old 10-29-2012
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yah the ans is transketolase
glucose>>>>glucose 6p>>>>6PG>>>>ribulose5po4-
>>>>ribose5po4>>>>>>>>>>>>>glyceraldehyde 3 po4->>>>fructose 5 po4-
(TRANSKETOLASE)
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Old 10-29-2012
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k..thanks for question..

i think i misunderstood the question...took long time to understand...

i thought the stem asking abt......what enzyme is essential(needed for them) in them rather than essential for pathway...................

i think @blade also thought same as me and answered...
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Old 10-29-2012
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@rupesh
Does it mean that G6PD def. also means Transketolase def?

My understanding from the question is since HMP shunt is malfunctioning, you give glutathione reductase to reduce oxidized glutathione?
Thank you
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Old 10-29-2012
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Quote:
Originally Posted by blade View Post
@rupesh
Does it mean that G6PD def.also means Transketolase def?

My understanding from the question is since HMP shunt is malfunctioning,you give glutathione reductase to reduce oxidized glutathione?
Thank you

your understanding is correct..

i think you didnt get his question buddy........he is asking the essential enzyme for forming ribose 5 po4 from fructose 6 po4?.....>.that's my understanding on this question

hope you got it now
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Old 10-29-2012
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Quote:
Originally Posted by rupesh View Post
Skome humans r unable to generate NADPH from Glucose metabolism but r able to synthesize ribose from fructose 6 po4-.which of the following enzymes r essesntial..
a)G6PD
b)glutathione reductase
c)enolase
d)transketolase
e)acotinase
d)transketolase
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Old 10-29-2012
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@blade
actually the above steps i mentioned are bidirectional ie fructose6po4->>>>Glyceraldehyde 3 po4->>>>ribose 5 po4__
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