Synthesizing Glucose from Pyruvate: Stuck at 3-phosphoglyceroylphosphate

[HazZy]

pyruvate ---> glucose

ok so my professor gave us the task of synthesizing glucose from pyruvate and I'm stuck somewhere near the middle .

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 can't figure out what to reduce it with! anyone know? my book doesn't seem to cover this step . thanks!

 

[LogicalAtheist]

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]

not true, glycolosis releases far too much energy to be reversed. however the step i needed was reversable, thanks.

 

[Monique]

And that energy is captured from sunlight by chloroplasts in plants :) The reaction IS reversable although it requires a lot of energy.

 

[LogicalAtheist]

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]

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]

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]

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.