Yersinia pseudotuberculosis and Yersinia pestis show increased outer membrane permeability to hydrophobic agents which correlates with lipopolysaccharide acyl-chain fluidity

Abstract

The hydrophobic probe N-phenyl-l-naphthylamine accumulated less in nonpathogenic Yersinia spp. and non-pathogenic and pathogenic Yersinia enterocolitica than in Yersinia pseudotuberculosis or Yersinia pestis. This was largely due to differences in the activity of efflux systems, but also to differences in outer membrane permeability because uptake of the probe in KCN/arsenate-poisoned cells was slower in the former group than in Y. pseudotuberculosis and Y. pestis. The probe accumulation rate was higher in Y. pseudotuberculosis and Y. pestis grown a t 37 "C than at 26 "C and was always highest in Y. pestis. These yersiniae had LPSs with shorter polysaccharides than Y. enterocolitica, particularly when grown a t 37 "C. pseudotuberculosis and Y. enterocolitica grown a t 26 "C were close below the Tc of the latter, they were always in a more fluid state than Y. enterocolitica LPS.Comparison with previous studies of Salmonella choleraesuis subsp. choleraesuis serotype minnesota rough LPS showed that the increased fluidity and absence of transition of Y. pseudotuberculosis and Y. pestis LPSs cannot be explained by their shorter polysaccharides and suggested differences a t the lipid Alcore level. It is proposed that differences in LPS-LPS interactions and efflux activity explain the above observations and reflect the adaptation of Yersinia spp. to different habitats.

The Lipopolysaccharide of Brucella abortus BvrS/BvrR Mutants Contains Lipid A Modifications and Has Higher Affinity for Bactericidal Cationic Peptides

“…2). Second, the higher sensitivity of the bvrS and bvrR mutants to surfactants (63) is another phenotype possibly explained by our observations since a correlation between OM permeability and LPS acyl-chain fluidity has been observed previously (2,3). Third, sensitivity to the bactericidal action of normal sera is a serious handicap for a pathogen.…”

The Omptins ofYersinia pestisandSalmonella entericaCleave the Reactive Center Loop of Plasminogen Activator Inhibitor 1

“…Acylation of LPS and substitution of lipid A phosphates with aminoarabinose have an indirect effect on the enzymatic activity of Pla in Y. pestis (62). At 37°C, Y. pestis expresses tetraacylated LPS, with a low content of aminoarabinose, and the outer membrane is more fluid (4,5,28), which increases the enzymatic activity of Pla (62). E. coli expresses mainly hexaacylated LPS, and this probably explains the slower formation of PAI-1* by Pla expressed in E. coli.…”

Effect of Bile on the Cell Surface Permeability Barrier and Efflux System of Vibrio cholerae

“…Samples were then suspended in 0.01 M CaCl 2 -0.1 M Tris-HCl (pH 7.3) buffer, digested with proteinase K, dialyzed extensively, freeze-dried, suspended in water, and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. To measure the binding of NPN to LPS aggregates, the LPS was thoroughly dispersed by sonication, supplemented with an equal volume of 0.2% sodium deoxycholate in 0.1 M Tris-HCl (pH 8.5), incubated at room temperature for 15 min, and precipitated with 6 volumes of ethanol at Ϫ20°C for 18 h. The precipitate was sedimented by centrifugation, washed with ethanol, suspended in water, and dialyzed, and the concentration was adjusted to 400 g ml Ϫ1 (2). NPN binding by LPS aggregates was determined as described for whole cells.…”