No abstract

The influence of lipoteichoic acid (LTA), which is the negatively charged component of the cell surface, on the bacteriostatic effect of bovine milk lactoferrin (bLF) was investigated. Cell agglutination in suspensions of 18 strains of Clostridium by iron-free and iron-saturated bLF (apo-bLF and Fe-bLF) was observed. The cell agglutination of Clostridium species by apo-bLF and Fe-bLF showed a significant correlation with the extent of the negative charge on the bacterial cell surface. The degree of cell agglutination of C. perfringens JCM1290 by bLF decreased with increasing LTA concentration. The growth suppressive ratio of bLF in the presence of LTA was also lower than that in the absence of LTA. The growth suppressive effect of bLF on C. perfringens JCM1290 was closely related to the cell agglutination by this protein. These results suggest that the direct interaction of bLF with the cell surface is necessary for the bacteriostatic effect of bLF.