Effect of lipid A aminoarabinosylation on Pseudomonas aeruginosa colistin resistance and fitness.

摘要: Colistin represents the last-line treatment option against many multidrug-resistant Gram-negative pathogens. Several lines of evidence indicate that aminoarabinosylation lipid A moiety lipopolysaccharide (LPS) is an essential step for development colistin resistance in Pseudomonas aeruginosa. However, whether it sufficient to confer this bacterium remains unclear. The aim work was investigate specific contribution P. aeruginosa and evaluate effect mechanism on bacterial fitness. Recombinant strains constitutively expressing enzymes were generated a small collection reference clinical isolates verified by quantitative reverse transcription polymerase chain reaction (qRT-PCR), extraction mass spectrometry. aminoarabinosylated found be strain- culture condition-dependent. Higher levels generally obtained presence divalent cations, which appear important aminoarabinosylation-mediated resistance. High also observed most human serum artificial sputum medium, should partly mimic growth conditions during infection. results growth, biofilm, cell envelope integrity Galleria mellonella infection assays does not cause relevant fitness costs