Antimicrobial Activity and Toxicity of the Major Lipopeptide Components of Polymyxin B and Colistin: Last-line Antibiotics against Multidrug-Resistant Gram-negative Bacteria.

ABSTRACT: Polymyxin B and colistin are currently used as a 'last-line' treatment for multidrug-resistant Gram-negative bacteria. However very little is known about the pharmacological differences between polymyxin B₁, polymyxin B₂, colistin A, colistin B, the major cyclic lipopeptides components present in polymyxin B and colistin products. Here, we report on the in vitro and in vivo antimicrobial activity and toxicity of these major lipopeptide components. All four lipopeptides had comparable MICs (<0.125-4 mg/L) against a panel of clinical Gram-negative isolates. They also had comparable in vivo antimicrobial activity (Δlog₁₀ CFU/mL >-3) and nephrotoxicity (mild to moderate histological damage) in mouse models. However, polymyxin B₁

SUBMITTER: Roberts KD 

PROVIDER: S-EPMC4980087 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature