title: Membrane filter (pore size, 0.22-0.45 micro m; thickness, 150 micro m) passing-through activity of Pseudomonas aeruginosa and other bacterial species with indigenous infiltration ability.
abstract: Bacteria growing on MF-Millipore filters (thickness, 150 micro m) passed through the underlying membrane by their infiltration activity. Bacillus subtilis, Staphylococcus aureus, Klebsiella pneumoniae, and Escherichia coli passed through a 0.45- micro m pore size filter within 48-96 h. Pseudomonas aeruginosa, Serratia marcescens, and Listeria monocytogenes passed through a 0.3- micro m pore size filter. P. aeruginosa passed through a 0.22- micro m pore size filter. The membranes which allowed passing-through of bacteria showed normal bubble point values in the integrity test. Studies with isogenic S. marcescens mutants indicated that flagellum-dependent motility or surface-active exolipid were important in the passing-through. P. aeruginosa PAO1 C strain defective in twitching motility was unable to pass through the 0.22- micro m filter. Scanning electron microscopy showed bacteria passing-through the 0.22- micro m filter. Millipore membrane filters having well-defined reticulate structures will be useful in the study of infiltration activity of microbes.
authors.affiliation: Department of Applied Biological Chemistry, Faculty of Agriculture, Niigata University, 950-2181, Niigata, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Kouta
authors.initials: K
authors.lastname: Naganuma
authors.forename: Yoji
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: Tohey
authors.initials: T
authors.lastname: Matsuyama
mesh_terms: D000362:Agar; D018441:Biofilms; D005374:Filtration / Q000295:instrumentation*; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D011550:Pseudomonas aeruginosa / Q000254:growth & development*; D013242:Sterilization / Q000295:instrumentation*
chemical_list: D008567:Membranes, Artificial; D000362:Agar