Perception and protection: The role of Bce-modules in antimicrobial peptide resistance.

Continual synthesis and remodeling of the peptidoglycan layer surrounding Gram-positive cells is essential for their survival. Diverse antimicrobial peptides target the lipid intermediates involved in this process. To sense and counteract assault from antimicrobial peptides, low G + C content gram-positive bacteria (Firmicutes) have evolved membrane protein complexes known as Bce-modules. These complexes consist minimally of an ABC transporter and a two-component system that work in tandem to perceive and confer resistance against antimicrobial peptides. In this mini-review I highlight recent breakthroughs in comprehending the structure and function of these unusual membrane protein complexes, with a particular focus on the BceAB-RS system present in Bacillus subtilis. [Display omitted] • Antimicrobial peptides bind to intermediates of the lipid II cycle. • Bce transporters provide resistance against antimicrobial peptides. • Bce-modules are a membrane protein complex of ABC transporter and histidine kinase. • Bce-modules utilize flux-sensing and target-protection mechanisms. [ABSTRACT FROM AUTHOR]