lactoferrin and magnesium-nitrate

Lactoferrin has been previously shown to be bactericidal for Legionella pneumophila. The current study showed that CaCl2, Mg(NO3)2, and MgCl2, but not NaCl, blocked killing. Activity was pH dependent with the greatest activity at 5.0. Sensitivity of the organism was dramatically affected by the growth conditions. Log phase 12 h, broth-grown cells were most sensitive, with older cultures becoming more resistant. Plate-grown cells were completely resistant. Lactoferrin binding, as detected by immunofluorescence microscopy, was temperature dependent (no binding at 4 degrees C), but was independent of killing.

Topics: Calcium Chloride; Fluorescent Antibody Technique; Humans; Hydrogen-Ion Concentration; Iron; Lactoferrin; Lactoglobulins; Legionella; Magnesium; Magnesium Chloride; Magnesium Compounds; Microbial Sensitivity Tests; Nitrates; Sodium Chloride; Temperature