Conversion of Six-Carbon Glucose to Three-Carbon Glyceraldehyde-3-PhosphateREFLECT AND APP...

Step

Reaction

Enzyme

ΔG °’*

ΔG**

kJ mol-1

kcal mol-1

kJ mol-1

1

Glucose + ATP → Glucose-6-phosphate + ADP

Hexokinase/Glucokinase

-16.7

-4.0

-33.9

2

Glucose-6-phosphate → Fructose-6-phosphate

Glucose phosphate isomerase

+ 1.67

+0.4

-2.92

3

Fructose-6-phosphate + ATP → Fructose-1, 6-bisphosphate + ADP

Phosphofructokinase

-14.2

-3.4

-18.8

4

Fructose-1,6-bisphosphate s Dihydroxyacetone phosphate + Glyceraldehyde-3-phosphate

Aldolase

+23.9

+5.7

-0.23

5

Dihydroxyacetone phosphate → Glyceraldehyde-3-phosphate

Triose phosphate isomerase

+7.56

+1.8

+2.41

6

2(Glyceraldehyde-3-phosphate + NAD+ + Pi → 1,3-bisphosphoglycerate + NADH + H+)

Glyceraldehyde-3-P

dehydrogenase

2( + 6.20)

2( + 1.5)

2(-1.29)

7

2(1,3-61sphosphoglycerate + ADP → 3-Phosphoglycerate + ATP)

Phosphoglycerate kinase

2(-18.8)

2(-4.5)

2(+0.1)

8

2(3-Phosphoglycerate → 2-Phosphoglycerate)

Phosphoglyceromutase

2(+4.4)

2(+1.1)

2(+0.83)

9

2(2-Phosphoglycerate → Phosphoenolpyruvate + H2O)

Enolase

2( + 1.8)

2(+0.4)

2(+1.1)

10

2(Phosphoenolpyruvate + ADP → Pyruvate + ATP)

Pyruvate kinase

2(-31.4)

2(-7.5)

2(-23.0)

Overall

Glucose + 2ADP + 2Pi + NAD+ → 2 Pyruvate → 2ATP + NADH + H+

2(Pyruvate + NADH + H+ → Lactate + NAD+) Glucose + 2ADP + 2Pi → 2 Lactate + 2ATP

Lactate dehydrogenase

-73.3

2(-25.1)

-123.5

-17.5

2(-6.0)

-29.5

-98.0 2(-14.8) -127.6