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HazZy
May21-03, 02:51 AM
ok so my professor gave us the task of synthesizing glucose from pyruvate and i'm stuck somewhere near the middle [g)].

showing all my work so far would clutter this thread quite a bit so i'll simplify.

pyruvate -> oxaloacetate -> phosphoenolpyruvate -> 2-phosphoglycerate -> 3-phosphoglycerate -> 3-phosphoglyceroylphosphate -> STUCK HERE!

i see i need to reduce 3-phosphoglyceroylphosphate then do keto-enol tautomerization in order for an aldol reaction to form fructose, but i cant figure out what to reduce it with! anyone know? my book doesn't seem to cover this step [s(]. thanks!

LogicalAtheist
May21-03, 11:21 AM
Glycolosis is the process by which glucose is turned into pyruvate.

Thus, you simple need to see this process, and reverse it.

Here is an explanation of Glycolosis:

http://www.people.virginia.edu/~rjh9u/glycol.html

HazZy
May21-03, 03:21 PM
not true, glycolosis releases far too much energy to be reversed. however the step i needed was reversable, thanks.

Monique
May21-03, 03:26 PM
And that energy is captured from sunlight by chloroplasts in plants :) The reaction IS reversable although it requires a lot of energy.

LogicalAtheist
May21-03, 03:34 PM
Originally posted by HazZy
not true, glycolosis releases far too much energy to be reversed. however the step i needed was reversable, thanks.


Come one now guy. Don't try to put controversy into something so simple.

Of course it's true. I've done this experiement myself, man. Not theoretically but experiementally.


Ugh.

HazZy
May21-03, 03:44 PM
can you please point me to a site that deals with the exact reverse reaction of glycolosis? and even if it can be reversed it would be a waste of time since gluconeogenesis(the reaction i was working on) is much more energy efficient [;)].

LogicalAtheist
May21-03, 04:04 PM
Originally posted by HazZy
can you please point me to a site that deals with the exact reverse reaction of glycolosis? and even if it can be reversed it would be a waste of time since gluconeogenesis(the reaction i was working on) is much more energy efficient [;)].

Not a waste of time if it can have unique results.

http://www.clas.ufl.edu/users/gbowes/bot3503/resp.htm

HazZy
May21-03, 05:57 PM
well see they call the reverse reaction of glycolosis "gluconeogenesis" only because you end with the reverse results of glycolosis. it isn't an exact reverse reaction due to the energy given off and three steps that are simply irreversable.

no biggie, it was just a minor correction [;)].

http://www.rci.rutgers.edu/~molbio/Courses/MBB_408_512/topics408a2002.pdf

7/10 steps are reversable and one of those 7 ended up being the step i was missing, so... thanks.