Answer Happy

The reverse aldol condensation is at the heart of the preparatory phase of glycolysis. A) Why is this reaction needed for the effective harvest of energy from glucose? In other words, why does the cell change the length of the glucose chain from one 6-carbon chain to two 3-carbon chains? B) The reverse aldol reaction requires a specific set of molecular features to be catalyzed. In Class I aldolases, this feature is governed by the chemistry of an active site lysine sidechain. In Class II aldolases, this feature is governed by the chemistry of an active site Zn²+ cation. Why are these features important in promoting the reverse aldol cleavage of fructose 1,6-bisphosphate (shown)? CHOPO₂²- Midterm Fo HO TH H- -OH H- -OH CH₂OPO3²-