Polymyxin

Typical uses are for infections caused by strains of multiple drug-resistant Pseudomonas aeruginosa or carbapenemase-producing Enterobacteriaceae.

The hydrophobic tail is important in causing membrane damage, suggesting a detergent-like mode of action.

However, it still detectably increases the permeability of the bacterial cell wall to other antibiotics, indicating that it still causes some degree of membrane disorganization.

[7][8] Polymyxins are a group of cyclic non-ribosomal polypeptide (NRPs) which are biosynthesized by bacteria belonging to the genus Paenibacillus.

The DAB residues cause polymyxins to have multiple positively charged groups at physiological pH.

The polymyxins are produced by nonribosomal peptide synthetase systems in Gram-positive bacteria such as Paenibacillus polymyxa.

The final steps involve a thioesterase domain at the C-terminal of the last module to cyclize the molecule and liberate the chain from the enzyme.