Binding of Lactoferrin to Bacterial Cells of the Clostridium Species and Their Agglutination

抄録

  Cell agglutination in cell suspensions of 10 strains of Clostridium by lactoferrin (Lf) was observed by obtaining the ratio of increased absorbance (RIA) at 450 nm. The RIA values were very different among the species, being higher in the cell suspensions with bovine Lf (bLf) than in those with human Lf. The binding ability of bLf to the bacterial cells was also observed by an enzyme-linked ligand-binding assay, using the conjugate of iron-free or iron-saturated bLf with horseradish peroxidase (HRPO). The binding ability of bLf was very different among the 10 species, and showed a significant correlation with the cell agglutination of each strain. bLf formed a complex with the cells of C. perfringens, did not dissociate in 2 M NaCl or 4 M urea, but did dissociate in 1 M KSCN. These results suggest that the agglutination of cells of the Clostridium species by bLf is probably caused by the cooperative action of at least electrostatic and hydrophobic interactions between bLf and certain components of the cell surface.