title: Bacterial attachment and viscoelasticity: physicochemical and motility effects analyzed using quartz crystal microbalance with dissipation (QCM-D).
abstract: This investigation is focused on the combined effect of bacterial physicochemical characteristics and motility on cell adhesion and deposition using a flow-through quartz crystal microbalance with dissipation (QCM-D). Three model flagellated strains with different degrees of motility were selected, including a highly motile Escherichia coli K12 MG1655, an environmental strain Sphingomonas wittichii RW1, and a nonmotile (with paralyzed flagella) Escherichia coli K12 MG1655 ΔmotA that is incapable of encoding the motor torque generator for flagellar movement. Of the three strains, S. wittichii RW1 is highly hydrophobic, while E. coli strains are equally hydrophilic. Consideration of the hydrophobicity provides an alternative explanation for the bacterial adhesion behavior. QCM-D results show that motility is a critical factor in determining bacterial adhesion, as long as the aquatic chemical conditions are conducive for motility and the substratum and bacterial surface are similarly hydrophobic or hydrophilic. Once their properties are not similar, the contribution of hydrophobic interactions becomes more pronounced. QCM-D results suggest that during adhesion of the hydrophobic bacterium, S. wittichii RW1, the initial step of adhesion and maturation of bacteria-substratum interaction on hydrophilic surface includes a dynamic change of the viscoelastic properties of the bond bacterium-surface becoming more viscously oriented.
authors.affiliation: Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Albert Katz International School for Desert Studies, Jacob Blaustein Institute for Desert Research, Ben Gurion University of the Negev, Israel 84990.
authors.forename: Jenia
authors.initials: J
authors.lastname: Gutman
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Walker
authors.forename: Viatcheslav
authors.initials: V
authors.lastname: Freger
authors.forename: Moshe
authors.initials: M
authors.lastname: Herzberg
mesh_terms: D001422:Bacterial Adhesion / Q000502:physiology*; D004548:Elasticity; D048168:Escherichia coli K12 / Q000502:physiology*; D057927:Hydrophobic and Hydrophilic Interactions; D009994:Osmolar Concentration; D011791:Quartz; D020578:Sphingomonas / Q000502:physiology*; D014783:Viscosity
chemical_list: D011791:Quartz