Novel role of bacterial lipocalins in cell protection against antibiotic-induced membrane lipid peroxidation

However, the mechanism to survive this stress is essentially unknown. The opportunistic pathogen Burkholderia cenocepacia encodes three genes that are upregulated under oxidative stress conditions such as sub-lethal concentration of antibiotic and superoxide ion stress.

One of these genes, bcnA, encodes a periplasmic protein from the lipocalin family, which is usually associated with a gene encoding a cytochrome b561 inner-transmembrane protein that we named lcoA; this synteny is conserved in the majority of the β-proteobacteria. Compared to the wild type, mutants lacking these proteins and psrA, a gene encoding a cytoplasmic aldehyde reductase that reduces toxic aldehydes, are more susceptible to bactericidal antibiotics and produce more lipid peroxidation by-products.