The outer membrane of Gram-negative bacteria acts as an effective barrier against toxic compounds, and therefore compromising this structure could increase sensitivity to currently available antibiotics. In this study, we show that the Mla pathway, a system involved in maintaining the integrity of the outer membrane, is genetically and functionally different in
Burkholderia cepaciacomplex species compared to that in other proteobacteria. Mutants in mlagenes of Burkholderia cenocepaciaor Burkholderia dolosawere sensitive to Gram-positive antibiotics, while this effect was not observed in Escherichia colior Pseudomonas aeruginosa. The Mla pathway in Burkholderiaspecies may represent an ideal genus-specific target to address their intrinsic antimicrobial resistances.