Q29-8P - Organic Chemistry (Mcmurry)

Question

PROBLEM 29-8 Look at the entire glycolysis pathway, and make a list of the kinds of organic reactions that take place-nucleophilic acyl substitutions, aldol reactions, E1cB reactions, and so forth.

Step-by-Step Solution

Answer

Glycolysis is made up of ten enzyme-catalyzed organic reactions, each of which is listed below and briefly described by a flow chart: 

 

Steps 1 and 3 Phosphate transfer reactions (phosphorylations).

 

Steps 2, 5, and 8 are isomerization steps.

 

Steps 4 The retro-aldol reaction.

 

Step 5 is a nucleophilic acyl substitution and oxidation.

 

Steps 7 and 10 Phosphate transfer reactions.

 

Step 9 ${\mathrm{E}}_1\mathrm{CB}$, i.e. Dehydration Elimination conjugate base process.

Introduction to the Concept

Glycolysis, also known as the Embden-Meyerhof-Parnas pathway, is a series of ten chemical events that occur in most cells to break down glucose and release energy, which is subsequently caught and stored in ATP.

Solution Explanation

1. Glucose is phosphorylated with ATP to produce glucose-6-phosphate (g-6-p).
2. Ring-opening and keto-enol tautomerization is used to convert g-6-p to F-6-P fructose-6-phosphate.
3. Phosphorylation of F-6-P occurs via a reaction involving ring-opening and keto-enol tautomerization.
4. Fructose 1,6-bisphosphate undergoes ring opening and is converted to glyceraldehyde-3-phosphate and dihydroxy acetone phosphate DHAPvia a retro-added type reaction.
5. Glyceraldehyde-3-phosphate dehydrogenase g-3-p glyceraldehyde-3-phosphate dehydrogenase g-3-p is oxidised to a carboxylic acid and then phosphorylated to yield 1,3-bisphosphoglycerate phosphoglycerate kinase 3-phosphoglycerate is formed when a phosphate is transferred from the carboxyl group to the ADP symmetries of an ATP. Therefore, the glycolysis involves 10 enzyme catalyst reactions.