Transformation of LTA4 to LTC4

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To generate LTC4, a supramolecular complex of 5-LOX, FLAP and leukotriene C4 synthase is formed on the nuclear membrane due to the increase of intracellular calcium \cite{Woods1993, Hammarberg2000, Radmark2015, Evans2008, Mandal2004, Mandal2008}

Chemical equation

$AA \rightleftharpoons PGH2$

Parameters

Michaelis-Menten Constants

Value	Units	Species	Notes	Reference
0.3 �± 0.06	mM	Human	Expression Vector: E. Coli. Enzyme: Wild Type hLTC4S pH:7.8 Temperature:20 °C
3.00E-02 ± 1.00E-02	mM	Human	Expression Vector: E Coli Enzyme: Wild type LTC4S pH: 7.8 Temperature: 37 °C

Enzyme Turnover Numbers

Value	Units	Species	Notes	Reference
702	per minute	Human	Expression Vector: E. Coli. Enzyme: Wild Type hLTC4S pH:7.8 Temperature:20 °C
1560 ± 240	per minute	Human	Expression Vector: E Coli Enzyme: Wild type LTC4S pH: 7.8 Temperature: 37 °C

LTC4S Abundance

Value	Units	Species	Notes	Reference
26.8	$ppm$	Human	Expression Vector: Lung Enzyme: LTC4S pH: 7.5 Temperature: 37 °C
33.0	$ppm$	Human	Expression Vector: Esophagus Enzyme: LTC4S pH: 7.5 Temperature: 37 °C
13.9	$ppm$	Human	Expression Vector: Adrenal Gland Enzyme: LTC4S pH: 7.5 Temperature: 37 °C

Gibbs Free Energy Change

Value	Units	Species	Notes	Reference
9.934128	kcal/mol	Not stated	Estimated Enzyme: LTC4S Substrate: LTA4 Product: LTC4 pH: 7.3 ionic strength: 0.25