Adhesion of Pseudomonas aeruginosa to silicone rubber in a parallel plate flow chamber in the absence and presence of nutrient broth.
The physico-chemical cell-surface properties of Pseudomonas aeruginosa AK1 and its adhesion to silicone rubber under flow were compared for cells suspended in phosphate-buffered saline (PBS) or PBS supplemented with 2% nutrient broth. Addition of 2% nutrient broth to cells suspended in PBS yielded minimal growth and did not significantly change the mean zeta potential of the organisms, which was around -13 mV. However, a comparatively larger proportion of the organisms had more negative zeta potentials in the presence of nutrient broth. This change was concurrent with a slight decrease in cell-surface hydrophobicity, as measured by water contact angles, from 119 degrees to around 112 degrees. The initial deposition rate of P. aeruginosa AK1 to silicone rubber, as studied in a parallel plate flow chamber, increased from 344 cm-2 s-1 in the absence of nutrient broth to 505 cm-2 s-1 in its presence. No stationary level of adhesion was observed in the presence of nutrient broth, instead the number of adhering cells increased steadily at a rate of approximately 85 cm-2 s-1. Fluorescent staining of adhering cells demonstrated that for adhesion from buffer only 2% of the adhering cells were metabolically active, whereas in case of deposition from PBS supplemented with nutrient broth, 67% of the adhering cells were metabolically active. It is concluded that the deposition rates measured in the parallel plate flow chamber with 2% nutrient broth added to the PBS suspension represent an interplay of adhesion and surface-associated growth.
Habash
Marc B
MB
Department of Microbiology and Immunology, University of Western Ontario Health Sciences Centre, London, Ontario, Canada N6A 5C1.
van der Mei
Henny C
HC
Materia Technica, University of Groningen, Bloemsingel 10, 9712 KZ Groningen, The Netherlands.
Reid
Gregor
G
Lawson Research Institute, London, Ontario Canada N6A 4V2.|Department of Microbiology and Immunology, University of Western Ontario Health Sciences Centre, London, Ontario, Canada N6A 5C1.
Busscher
Henk J
HJ
Materia Technica, University of Groningen, Bloemsingel 10, 9712 KZ Groningen, The Netherlands.|Department of Microbiology and Immunology, University of Western Ontario Health Sciences Centre, London, Ontario, Canada N6A 5C1.
D001422:Bacterial Adhesion; D001672:Biocompatible Materials; D002021:Buffers; D003470:Culture Media; D005559:Formamides / Q000737:chemistry; D006847:Hydrocarbons, Iodinated / Q000737:chemistry; D007091:Image Processing, Computer-Assisted; D008564:Membrane Potentials; D009281:Naphthalenes / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000254:growth & development*; D012826:Silicone Elastomers; D012965:Sodium Chloride; D014867:Water / Q000737:chemistry
D001672:Biocompatible Materials; D002021:Buffers; D003470:Culture Media; D005559:Formamides; D006847:Hydrocarbons, Iodinated; D009281:Naphthalenes; D012826:Silicone Elastomers; D014867:Water; C027946:methylene iodide; D012965:Sodium Chloride; C031066:formamide; C108222:alpha-bromonaphthalene