Hexose-6-phosphate isomerase

The enzyme Hexose-6-phosphate isomerase converts Glucose 6-phosphate (Glc6P) into its isomer Fructose 6-phosphate (Fru6P). Isomers have the same molecular formula, but the atoms of each molecule are arranged differently.

Chemical reaction

$Glc6P \rightleftharpoons Fru6P$

Rate equation

Reversible competitive inhibition with Ery4P, 6PG and FBP.

Failed to parse (Cannot store math image on filesystem.): \frac{V_{mf}\frac{[Glc6P]}{Km_{Glc6P}} - V_{mr} \frac{[Fru6P]}{Km_{Fru6P}} }{ 1 + \frac{[Glc6P]}{Km_{Glc6P}} + \frac{[Fru6P]}{Km_{Fru6P}} + \frac{[ERY4P]}{Ki_{ERY4P}} + \frac{[6PG]}{Ki_{6PG}} + \frac{[Fru1,6BP]}{Ki_{Fru1,6BP}} }

Parameters

Parameter	Value	Units	Organism	Remarks
$V_{mf}$	0.4	$mM \times min^{-1}$	HeLa cell line	3 cell assays
$V_{mr}$	0.9	$mM \times min^{-1}$		1 cell assay
$Km_{Glc6P}$	0.4 $\pm$ 0.03 mM	mM		3 cell assays
$Km_{Fru6P}$	0.05	mM		2 cell assays
$Ki_{ERY4P}$	0.001	mM		Adjusted in the interval based on activity
$Ki_{Fru1,6BP}$	0.06	mM		Adjusted in the interval based on activity
$Ki_{6PG}$	0.015	mM		Adjusted in the interval based on activity