33. The Organic Chemistry of Metabolic Pathways

Classify each one of the following reactions as phosphorylation (P), isomerization (I), or neither (N).

a) ____ Conversion of glucose into glucose-6-phosphate.

b) ____ Conversion of glucose-6-phosphate into fructose-6-phosphate.

c) ____ Conversion of DHAP into G3P.

d) ____ Cleavage of fructose-1,6-bisphosphate into DHAP and G3P.

Which one of the following compound pairs is produced by cleavage of fructose-1,6-bisphosphate?

Identify which carbon atoms of fructose 1,6-bisphosphate become carbonyl groups in dihydroxyacetone phosphate and glyceraldehyde 3-phosphate when it undergoes a retro aldol reaction in step 4 of glycolysis.

Identify the mechanism for each of the following reactions as NAS, E1cB, or S_N2.

a) ____ Dehydration of 2-phosphoglycerate to produce phosphoenolpyruvate.

b) ____ Conversion of 1,3-bisphosphoglycerate into 3-phosphoglycerate.

c) ____ Conversion of glucose into glucose-6-phosphate.

d) ____ Conversion of 3-phosphoglycerate into 2-phosphoglycerate.

If the P atom in 3-phosphoglycerate is labelled with phosphorous-32, where does the label end up after it is isomerized to 2-phosphoglycerate in step 8 of glycolysis?