Polymyxin B Loosens Lipopolysaccharide Bilayer but Stiffens Phospholipid Bilayer.

ABSTRACT: Multidrug-resistant Gram-negative bacteria have increased the prevalence of a variety of serious diseases in modern times. Polymyxins are used as the last-line therapeutic options for the treatment of infections. However, the mechanism of action of polymyxins remains in dispute. In this work, we used a coarse-grained molecular dynamics simulation to investigate the mechanism of the cationic antimicrobial peptide polymyxin B (PmB) interacting with both the inner and outer membrane models of bacteria. Our results show that the binding of PmB disturbs the outer membrane by displacing the counterions, decreasing the orientation order of the lipopolysaccharide tail, and creating more lipopolysaccharide packing defects. Upon binding onto the inner membrane, in contrast to the traditional killing

SUBMITTER: Fu L 

PROVIDER: S-EPMC6950770 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature