Yersinia pseudotuberculosis and Yersinia pestis are more resistant to bactericidal cationic peptides than Yersinia enterocolitica.
The action of bactericidal polycationic peptides was compared in Yersinia spp. by testing peptide binding to live cells and changes in outer membrane (OM) morphology and permeability. Moreover, polycation interaction with LPS was studied by measuring the dependence of dansylcadaverine displacement and zeta potential on polycation concentration. When growth at 37 degrees C, Yersinia pestis and Yersinia pseudotuberculosis bound less polymyxin B (PMB) than pathogenic or non-pathogenic Yersinia enterocolitica, regardless of virulence plasmid expression. Y. pseudotuberculosis OMs were unharmed by PMB concentrations causing extensive OM blebbing in Y. enterocolitica. The permeability to lysozyme caused by PMB was greater in Y. enterocolitica than in Y. pseudotuberculosis or Y. pestis and differences increased at 37 degrees C. Similar observations were made with other polycations using a polymyxin/novobiocin permeability assay. With LPS of cells grown at 26 degrees C, polycation binding was highest for Y. pseudotuberculosis and lowest for Y. pestis, with Y. enterocolitica yielding intermediate results which were lower for pathogenic than for non-pathogenic strains. With LPS of cells grown at 37 degrees C, polycation binding remained unchanged for Y. pestis and pathogenic Y. enterocolitica, increased for non-pathogenic Y. enterocolitica and decreased for Y. pseudotuberculosis to Y. pestis levels. Polycation binding related in part to differences in charge density (zeta potential) of LPS aggregates, suggesting similar effects at bacterial surfaces. It is suggested that species and temperature differences in polycation resistance relate to infection route, invasiveness and intracellular multiplication of Yersinia spp.
Bengoechea
José-Antonio
JA
Forschungzentrum Borstel, Division of Biophysics, Borstel, Germany.|Departamento de Microbiología, Universidad de Navarra, Aptdo. 177, 31080 Pamplona, Spain.
Lindner
Buko
B
Forschungzentrum Borstel, Division of Biophysics, Borstel, Germany.
Seydel
Ulrich
U
Forschungzentrum Borstel, Division of Biophysics, Borstel, Germany.
Ramón
Díaz
D
Departamento de Microbiología, Universidad de Navarra, Aptdo. 177, 31080 Pamplona, Spain.
Ignacio
Moriyón
M
Departamento de Microbiología, Universidad de Navarra, Aptdo. 177, 31080 Pamplona, Spain.
D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics; D002462:Cell Membrane / Q000187:drug effects; D004352:Drug Resistance, Microbial; D006801:Humans; D008070:Lipopolysaccharides / Q000378:metabolism; D009675:Novobiocin / Q000493:pharmacokinetics; D011112:Polymyxin B / Q000378:metabolism / Q000494:pharmacology; D013696:Temperature; D015008:Yersinia enterocolitica / Q000187:drug effects* / Q000378:metabolism; D015010:Yersinia pestis / Q000187:drug effects* / Q000378:metabolism; D015011:Yersinia pseudotuberculosis / Q000187:drug effects* / Q000378:metabolism
D000900:Anti-Bacterial Agents; D008070:Lipopolysaccharides; D009675:Novobiocin; D011112:Polymyxin B