Bacterial phosphorylcholine decreases susceptibility to the antimicrobial peptide LL-37/hCAP18 expressed in the upper respiratory tract.

ABSTRACT: A number of pathogens of the upper respiratory tract express an unusual prokaryotic structure, phosphorylcholine (ChoP), on their cell surface. We tested the hypothesis that ChoP, also found on host membrane lipids in the form of phosphatidylcholine, acts so as to decrease killing by antimicrobial peptides that target differences between bacterial and host membranes. In Haemophilus influenzae, ChoP is a phase-variable structure on the oligosaccharide portion of the lipopolysaccharide (LPS). There was a bactericidal effect of the peptide LL-37/hCAP18 on a nontypeable H. influenzae strain, with an increasing selection for the ChoP(+) phase as the concentration of the peptide was raised from 0 to 10 microgram/ml. Moreover, constitutive ChoP-expressing mutants of unrelated strains showed up to

SUBMITTER: Lysenko ES 

PROVIDER: S-EPMC97327 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature