title: Assessment of molecular sieving across bacterial outer membrane of Pseudomonas.
abstract: The role of the permeability barrier of the outer membrane of Pseudomonas was re-evaluated based on the physical theory of molecular sieving in view of its intrinsic antibiotic resistance. We developed a set of analytical procedures based on parametric and non-parametric statistical tests to evaluate, validate and adopt the better among a set of competing non-linear models of diffusion. The molecular mass dependence of uptake of non-electrolytes in bacteria yielded a quantitative measure to distinguish between sieving mechanisms and specific uptake/efflux mechanisms. The experimental data, supported by the physical model of DEAE-Sephadex and various analytical models and extensive simulation of the errors, both in measurement and models, yielded evidence consistent with the relaxation of the outer membrane matrix barrier in Pseudomonas.
authors.affiliation: Department of Biotechnology, University of Pune, India.
authors.forename: S B
authors.initials: SB
authors.lastname: Kulkarni
authors.forename: V
authors.initials: V
authors.lastname: Somlata
authors.forename: V
authors.initials: V
authors.lastname: Sitaramam
mesh_terms: D050260:Carbohydrate Metabolism; D002462:Cell Membrane / Q000648:ultrastructure; D002463:Cell Membrane Permeability / Q000187:drug effects; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology; D002852:Chromatography, Ion Exchange; D004058:Diffusion; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000502:physiology / Q000648:ultrastructure; D008433:Mathematics; D008954:Models, Biological; D008970:Molecular Weight; D009391:Nephelometry and Turbidimetry; D009994:Osmolar Concentration; D011550:Pseudomonas aeruginosa / Q000502:physiology* / Q000648:ultrastructure; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology
chemical_list: D002593:Cetrimonium Compounds; D012967:Sodium Dodecyl Sulfate; D000077286:Cetrimonium