title: Effect of surface lipopolysaccharide on the nature of membrane vesicles liberated from the Gram-negative bacterium Pseudomonas aeruginosa.
abstract: Membrane vesicles (MVs) were isolated from three isogenic lipopolysaccharide (LPS) mutants derived from the Gram-negative bacterium Pseudomonas aeruginosa PAO1 and compared with the parent strain. Parent cells possessed serotype 05 (A+B+) LPS whereas the three mutants contained A+B-, A-B+ and A-B-. The MVs from the mutants contained their expected phenotypic LPS and varied in size, especially A-B- MVs. Mass and total protein differences were also noted. When the parent and mutant cells were treated with the outer membrane-perturbing antibiotic gentamicin, all cells produced 3-5 times more MVs and these had great variation in size, mass and total protein. It is concluded that the type of cellular LPS affects both the natural and gentamicin-induced development of MVs.
authors.affiliation: Department of Microbiology and Canadian Bacterial Disease Network-NCE University of Guelph, Guelph, Ontario, Canada N1G 2W1.
authors.forename: Trang T
authors.initials: TT
authors.lastname: Nguyen
authors.forename: Anu
authors.initials: A
authors.lastname: Saxena
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Beveridge
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001433:Bacteriolysis; D002462:Cell Membrane / Q000187:drug effects / Q000648:ultrastructure*; D005839:Gentamicins / Q000494:pharmacology*; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000235:genetics; D008070:Lipopolysaccharides / Q000737:chemistry / Q000494:pharmacology*; D008854:Microscopy, Electron; D009154:Mutation; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics; D022161:Transport Vesicles / Q000187:drug effects / Q000648:ultrastructure*
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D008070:Lipopolysaccharides