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Glycolysis oxidation states - (Aug/25/2014 )

I figured out the oxidation states and how they change in each reaction of glycolysis

 

Glucose:

O = -2

C1 = +1

C2-5 = 0

C6 = -1

H = +1

 

Glucose 6-Phosphate

 

C = no change

O bonded to phosphate = -1

P = +5

Other Os = no change

 

Here O has been oxidized by phosphate

 

Fructose 6-Phosphate

C3-C4 = no change

C2 = +2

C1 = -1

O = no change

P = no change

 

Here C2 was oxidized and C1 was reduced in the isomerization from glucose to fructose

 

Fructose 1,6-Bisphosphate

 

O bonded to phosphate: -1

P = +5

C = no change

 

Again O has been oxidized by phosphate

 

Since both of the O's were oxidized by phosphate and ATP was used that means that the ATP has been reduced

 

Dihydroxyacetone Phosphate

 

C3 = -1

C2 = +2

C1 = -1

 

C3 is bonded to O which is bonded to phosphate and C1 is bonded to OH. OH takes priority over phosphate.

 

C3 has been reduced

 

Phosphoglyceraldehyde

 

C3 = -1

C2 = 0

C1 = +1

 

In the isomerization C2 has been reduced and C1 has been oxidized

 

1,3-Bisphosphoglycerate

 

C1 = +3

O bonded to phosphate = -1

 

Here both C1 and the O have been oxidized

 

3-phosphoglycerate

O- = -1

 

O didn't change its oxidation state but it did become negatively charged

 

2-phosphoglycerate

O in OH = -2

O- = no change

O bonded to phosphate = -1

 

Here the phosphate moved to the other O and so the O that was originally bonded to the phosphate has been reduced and the O bonded to C2 has been oxidized. ADP was also oxidized to ATP when 1 phosphate came off of 1,3-Bisphosphoglycerate.

 

Phosphenolpyruvate(I don't know why phenol is put in there when there isn't actually a benzene ring bonded to an OH(Which is what phenol is). Why not just phosphopyruvate or something along those lines?)

 

C3 = -2

C2 = +1

 

C2 has been oxidized and C3 has been reduced.

 

Pyruvate

 

O=C2 = -2

C3 = -3

C2 = +2

 

Here the O has been reduced, C3 has been reduced, and C2 has been oxidized. ADP has also been oxidized to ATP.

 

 

Now how does this mean that glucose has been oxidized to pyruvate when as you just saw with the oxidation states and how they changed the glucose has been both oxidized and reduced?

-caters-

caters on Mon Aug 25 15:54:18 2014 said:

Phosphenolpyruvate(I don't know why phenol is put in there when there isn't actually a benzene ring bonded to an OH(Which is what phenol is). Why not just phosphopyruvate or something along those lines?)


It's because you misspelled it - phosphoenolpyruvate - it is an enol not a phenol.

 

IIRC, the oxidation state of oxygen is always -2 unless it is in a peroxide, so some of your calculations might be out a little.

-bob1-

Well maybe the alkoxide but not in the O-Phosphate bond because that has a peroxide bond(fancy way of saying O-O single bond).

-caters-

OK,I'll take your word for it. I should probably review my chemistry sometime, it's not something I use much anymore.

-bob1-