. 1996 Dec 24;93(26):15069–15074. doi: 10.1073/pnas.93.26.15069

Table 1.

Substrate specificity of PGH synthase peroxidases and GSH-Px

Substrate	PGH synthase-1^*			PGH synthase-2			GSH-Px^† NADPH oxidation, mol × 10⁻⁷
Substrate	K_m, μM	V^*_max	V^*_max/K_m	K_m, μM	V^*_max	V^*_max/K_m	GSH-Px^† NADPH oxidation, mol × 10⁻⁷
Peroxynitrite	140	759	5.4	100	287	2.9	0.08
15-HPETE	24	237	9.7	9	59	6.3	1.54
H₂O₂	287	692	2.4	109	167	1.5	1.69

PGH synthase peroxidase assays were performed as described. The units of V^*_max are mol guaiacol oxidized per mol PGH synthase. The rates of guaiacol oxidation were determined over a range of peroxide concentrations, and control assays were performed in the absence of enzyme to correct for nonenzymatic oxidation.

^†

GSH-Px assays were conducted as described.