Effect of some physical and chemical factors on the bactericidal activity of human lactoferrin and transferrin against Yersinia pseudotuberculosis.

Abstract

The iron-chelating proteins lactoferrin and transferrin have been shown to be bactericidal for a variety of organisms. In this study, the effect of pH, temperature, their concentration, and magnesium and calcium on the bactericidal activity against Yersinia pseudotuberculosis was investigated. The bactericidal activity of lactoferrin was higher at acid pH, whereas, the bactericidal activity of transferrin was higher at alkaline pH. Both were not efficient at 4 degrees, 15 degrees, and 25 degrees C, but they were efficient at 37 degrees C. Lactoferrin, but not transferrin, was very efficient at 42 degrees C. The activity of both were time and concentration dependent. Calcium did not effect their activity up to 60 mM, whereas, magnesium reduced the activity of lactoferrin only.