Molecular Interaction between Lipoteichoic Acids and Lactobacillus delbrueckii Phages Depends on D-Alanyl and Alpha-Glucose Substitution of Poly(Glycerophosphate) Backbones

Abstract

Lipoteichoic acids (LTAs) have been shown to act as bacterial counterparts to the receptor binding proteins of LL-H, LL-H host range mutant LL-H-a21, and JCL1032. Here we have used LTAs purified by hydrophobic interaction chromatography from different phage-resistant and -sensitive strains of Lactobacillus delbrueckii subsp. lactis. Nuclear magnetic resonance analyses revealed variation in the degree of {alpha}-glucosyl and D-alanyl substitution of the 1,3-linked poly(glycerophosphate) LTAs between the phage-sensitive and phage-resistant strains. Inactivation of phages was less effective if there was a high level of D-alanine residues in the LTA backbones. Prior incubation of the LTAs with {alpha}-glucose-specific lectin inhibited the LL-H phage inactivation. The overall level of decoration or the specific spatial combination of {alpha}-glucosyl-substituted, D-alanyl-substituted, and nonsubstituted glycerol residues may also affect phage adsorption.