While the conversion of glucose (Glc) to pyrucate (Pyr) is shared across all domains of life, the route to get there can differ dramatically. In some Archaea, for example, some of the key steps in glycolysis differ. One example of this is the conversion of glyceraldehyde 3-phosphate (GAP) to 3-phosphoglycerate (3PG). Instead of the two-step process catalyzed by GAPDH and PGK: GAPDH GAP + Pi + NAD+ -----> BGP + NADH PGK BGP + ADP <-----> 3PG + ATP The archaeal pathway utilizes the enzyme non-phosporylating glyceraldehyde-3-phosphate dehydrogenase (GAPN) to catalyze the metabolically irreversible step shown below:
While the conversion of glucose (Glc) to pyrucate (Pyr) is shared across all domains of life, the route to get there can differ dramatically. In some Archaea, for example, some of the key steps in glycolysis differ. One example of this is the conversion of glyceraldehyde 3-phosphate (GAP) to 3-phosphoglycerate (3PG). Instead of the two-step process catalyzed by GAPDH and PGK:
GAPDH
GAP + Pi + NAD+ -----> BGP + NADH
PGK
BGP + ADP <-----> 3PG + ATP
The archaeal pathway utilizes the enzyme non-phosporylating glyceraldehyde-3-phosphate dehydrogenase (GAPN) to catalyze the
GAPN
GAP + NADP+ ---> BGP + NADPH
In terms of the ΔGrxn, why is the GAPDH+PGK process reversible but the GAPN process is not?
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 3 images
