Definition:

Heme-containing oxidoreductase which catalyzes the conversion of thiocyanate (SCN(-)) into antimicrobial agent hypothiocyanous acid (OSCN(-)) in the presence of hydrogen peroxide (H2O2) (By similarity). Also involved in the conversion of iodide (I(-)) into hypoiodite (IO(-)) in the presence of H2O2 (By similarity). Responsible for the inactivation of a wide range of micro-organisms and hence, important component of defense mechanism. Shows antibacterial properties against Pseudomonas aeruginosa. The lactoperoxidase-SCN(-)-H2O2 system shows antibacterial properties against Burkholderia cepacia and Haemophilus influenzae in vitro. Present in mammary and salivary gland secretions and may contribute to airway host defense against infection. May contribute to maintaining an appropriate H2O2 cellular level, therefore protecting cells from H2O2-caused injuries and inflammation (By similarity).