Table 1.

Overview of bacterial resistance mechanisms against antimicrobial peptides.

mechanisms	Gram-positive bacteria	Gram-negative bacteria
extracellular proteins	proteolytic degradation sequestration	proteolytic degradation
exopolymers	PIA, PGA	alginate, polysialic acid
surface modification	repulsion by d-alanylation of TA steric hindrance by l-rhamnosylation of WTA lipid II modification	repulsion by lipid A phosphate modification increased OM rigidity by lipid A acylation O-antigen of LPS
cytoplasmic membrane alteration	charge repulsion by PG amino-acylation	increased IM rigidity by PG acylation
efflux pumps	export by ABC transporters	export by RND family efflux pumps