Table 1.

Uric acid inhibits the bactericidal effect of the myeloperoxidase/H₂O₂/Cl^- system.

Treatment	CFU/mL × 105
Growth minimum medium	60.0 ± 12.0
H2O2	49.0 ± 3.0
MPO/Cl-/H2O2	0*
MPO/Cl-/H2O2/UA	28.5 ± 4.5#

Myeloperoxidase (MPO, 100 nM), NaCl (150 mM), H₂O₂ (100 μM) were incubated or not with uric acid (UA, 0.5 mM) in minimum medium for 30 min. Catalase (50 µg/mL) was added to remove H₂O₂ and stop the reaction. PA14 (1 × 10⁶/mL) was incubated with this system for 2 h and colony-forming units (CFU) were counted after overnight growth. Results represent the mean ± SEM of three independent experiments. Statistical analyses were performed by one-way ANOVA followed by Newman-Keuls post-hoc test; *p < 0.05 compared with minimum media and ^#p < 0.05 compared with MPO/Cl^-/H₂O₂.