Glyceraldehyde-3-phosphate dehydrogenase
The Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) enzyme serves two functions in glycolytic pathway. First the enzyme transfers a hydrogen (H-) from glyceraldehyde phosphate (Gly3P) to the oxidizing agent Nicotinamide Adenine Dinucleotide (NAD+) to form NADH. Next it adds a phosphate (P) from the cytosol to the oxidized Gly3P to form 1, 3-bisphosphoglycerate.
Contents
Chemical equation
![NAD + Gly3P + Pi \rightleftharpoons 1,3BPG + NADH](/wiki/images/math/2/a/f/2af9044ebf6cb3006254f1fcb443f8cf.png)
Rate equation
Ordererd Ter-Bi reversible Michaelis-Menten equation for non-interacting substrates. [1]
![v = \frac{ V_{mf}\frac{[NAD][Gly3P][Pi]}{K_{NAD}K_{Gly3P}K_{Pi}} - V_{mr} \frac{[1,3BPG][NADH]}{K_{1,3BPG}K_{NADH}} }{1 + \frac{[NAD]}{K_{NAD}} + \frac{[NAD][Gly3P]}{K_{NAD}K_{Gly3P}} + \frac{[NAD][Gly3P][Pi]}{K_{NAD}K_{Gly3P}K_{Pi}} + \frac{[1,3BPG][NADH]}{K_{1,3BPG}K_{NADH}} + +\frac{[NADH]}{K_{NADH}} }](/wiki/images/math/c/e/c/cec09052887411fec63867405d65296f.png)
Parameters
Parameter | Value | Units | Organism | Remarks |
---|---|---|---|---|
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0.58 [2] | ![]() |
HeLa cell line | |
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0.72[2] | ![]() | ||
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0.19[1] | mM | ||
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0.022[1] | mM | ||
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0.09[1] | mM | ||
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0.01[1] | mM | ||
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29[1] | mM |
Parameters with uncertainty
- Four values of
have been collected from Lambeir et. al. (1991)[3] for different organisms.
for Trypanosoma brucei,
for Homo sapiens,
for Geobacillus stearothermophilus and
for Oryctolagus cuniculus. Calculating mean and std. dev. from these 4 values gives
- Three values collected under different conditions from human cell is reported for
in Ryzlak (1998) et. al. [4]. Those values are 0.01, 0.02, 0.027. The mean and Std. Dev. from these three values are
- Three values for
have also been reported under different conditions from human cell in Ryzlak (1998) et. al. [4]. Those values are 0.01, 0.012, 0.018. The mean and Std. Dev. from these three values are
Parameter | Value | Units | Organism | Remarks |
---|---|---|---|---|
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![]() |
![]() |
HeLa cell line | |
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||
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0.19[1] | mM | ||
![]() |
![]() |
mM | ||
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![]() |
mM | ||
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mM | Multiple organism | |
![]() |
29[1] | mM |
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Marín-Hernández A, Gallardo-Pérez JC, Rodríguez-Enríquez S et al (2011) Modeling cancer glycolysis. Biochim Biophys Acta 1807:755–767 (doi)
- ↑ 2.0 2.1 2.2 2.3 Marín-Hernández A , Rodríguez-Enríquez S, Vital-González P A, et al. (2006). Determining and understanding the control of glycolysis in fast-growth tumor cells. Flux control by an over-expressed but strongly product-inhibited hexokinase. FEBS J., 273 , pp. 1975–1988(doi)
- ↑ Lambeir, A.M.; Loiseau, A.M.; Kuntz, D.A.; Vellieux, F.M.; Michels, P.A.M.; Opperdoes, F.R. (1991), The cytosolic and glycosomal glyceraldehyde-3-phosphate dehydrogenase from Trypanosoma brucei. Kinetic properties and comparison with homologous enzymes, Eur. J. Biochem. 198, 429-435
- ↑ 4.0 4.1 Ryzlak, M.T.; Pietruszko, R. (1998), Heterogeneity of glyceraldehyde-3-phosphate dehydrogenase from human brain, Biochim. Biophys. Acta 954, 309-324