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smal
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09/14/06 - 10:49 PM

increase in the activity of which of the following enzymes is most likely to increae the metabolism of G -6-P through glycolysis in liver
1. fructose-1,6- bisphosphate
2. fructose -1,6- bisphosphate aldose
3.fructose-2,6- bisphosphate
4.glucokinase
5.6-phoshofructokinase-1-kinase

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blueocean
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09/15/06 - 05:18 AM

drpkaur
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09/15/06 - 08:57 AM

isn't it PFK-1...RATE LIMITING STEP IN GLYCOLYSIS..5....

smal
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09/15/06 - 09:47 AM

well i was thinking like drpkaur too until my friend said it is glucokinase since its activity will ensure substrate for G6P formation.
what do u say guys

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remedy for weakness is not brooding over it ,but thinking of strength.

blueocean
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09/15/06 - 10:42 AM

I guess drpkaur is right! Is so easy with this type of question to make stupid mistakes!..
http://www.indstate.edu/thcme/mwking/glycolysis.h...

smal
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09/15/06 - 06:13 PM

thanks blue ocean,
its a gr8 link

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remedy for weakness is not brooding over it ,but thinking of strength.

young_doc
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09/15/06 - 07:16 PM

The answer could also be 3. PFK-2.

PFK-2 is activated by Insulin, and converts F6P to F2,6P.

F2,6P in turn ACTIVATES PFK-1.......

(to help you review)

http://www.indstate.edu/thcme/mwking/fructose26bi...

If anyone knows why F2,6P is wrong plz post. Thanks =)

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usamle7
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09/15/06 - 08:14 PM

i think F26-BP is right...its in the liver and is activated by insulin

eytanraz
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09/16/06 - 06:59 AM

usamle7 wrote:
i think F26-BP is right...its in the liver and is activated by insulin

yes but the answer is "3.fructose-2,6- bisphosphate ", which is not an enzyme

young_doc
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09/16/06 - 09:57 AM

#10

eytanraz wrote:

yes but the answer is "3.fructose-2,6- bisphosphate ", which is not an enzyme

that's right!!! I should have read the question more carefully. Though increased F2,6P would also be right, it's not an answer!

So i guess the answer remains 6-phoshofructokinase-1-kinase...also known as PFK-1!

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young_doc
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09/16/06 - 09:58 AM

#11

OOPS! I meant to say "F2,6P...it's not an ENZYME"

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