Similar temperature dependencies of glycolytic enzymes: an evolutionary adaptation to temperature dynamics?

Table 1 Thermodynamic equilibrium constants (K _eq ) of selected glycolytic reactions at 12 and 30°C

Enzyme	Abrev.	K_eq		Fold change
		12°C	30°C
Hexokinase	HXK	7.7 x10³	3.5 x10³	0.45
Phosphoglucose isomerase	PGI	0.27	0.29	−0.93
Phosphofructokinase	PFK	5.0 x10³	2.4 x10³	2.08
Fructose-1,6-biphosphate aldolase	FBA	9.3 x10^-4	1.4 x10^-3	−1.51
Triosphosphate isomerase	TPI	0.040	0.048	−1.20
Glyceraldehyde-3-phosphate dehydrogenase	TDH	0.66	0.69	−1.05
Phosphoglycerate kinase	PGK	20	16	1.25
Phosphoglycerate mutase	PGM	0.074	0.087	−1.18
Enolase	ENO	5.1	4.5	1.13
Pyruvate kinase	PYK	3.9 x10⁴	1.4 x10⁴	2.79

K_eq values were calculated from [24] considering a reference condition of 298.15 K, I = 0.25M and pH 7.0. The fold change refers to the ratio K_eq^12°C/K_eq^30°C.

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