Outer membranes of gram-negative bacteria are permeable to steroid probes.

@article{Plsiat1992OuterMO,
  title={Outer membranes of gram-negative bacteria are permeable to steroid probes.},
  author={P Pl{\'e}siat and Hiroshi Nikaido},
  journal={Molecular microbiology},
  year={1992},
  volume={6 10},
  pages={1323-33}
}
The permeability of bacterial outer membranes was assayed by coupling the influx of highly hydrophobic probes, 3-oxosteroids, with their subsequent oxidation catalysed by 3-oxosteroid delta 1-dehydrogenase, expressed from a gene cloned from Pseudomonas testosteroni. In Salmonella typhimurium producing wild-type lipopolysaccharide, the permeability coefficients for uncharged steroids were 0.45 to 1 x 10(-5) cm s-1, and the diffusion appeared to occur mainly through the lipid bilayer domains of… CONTINUE READING