Table 2. Steady state kinetic parameters of mLTC4S and hLTC4S against GSH and LTA₄.

	mLTC4S			hLTC4S
Substrate	k cat (s−1)	K M (µM)	k cat/K M(s−1 M−1)	k cat (s−1)	K M (µM)	k cat/K M(s−1 M−1)
LTA4	81±7.0	36±8	(2.3±0.26)×106	15.5±0.8	23±3	(0.6±0.057)×106
GSH	84±5.7	1200±240	(6.8±0.8)×104	12±0.7	300±60	(4.0±1.1)×104 **

The enzyme activity was measured in 25mM Tris (pH 7.8), 0.1M NaCl, 0.05% DDM in the presence of either 30 µM LTA₄ and/or 5 mM GSH with 0.1 µg of enzyme.

**[29].