title: Effect of antimicrobial residues on early adhesion and biofilm formation by wild-type and benzalkonium chloride-adapted Pseudomonas aeruginosa.
abstract: Antimicrobial residue deposition can change the physico-chemical properties of bacteria and surfaces and thus promote or impair bacterial adhesion. This study focuses on benzalkonium chloride (BC) deposition on polystyrene (PS) surfaces and the influence of this conditioning film on the physico-chemical properties of PS and on early adhesion and biofilm formation by Pseudomonas aeruginosa wild-type and its laboratory BC-adapted strain. The latter readily acquired the ability to grow in BC, and also exhibited physico-chemical surface changes. The existence of residues on PS surfaces altered their hydrophobicity and favoured adhesion as determined by the free energy and early adhesion characterization. Adapted bacteria revealed a higher ability to adhere to surfaces and to develop biofilms, especially on BC-conditioned surfaces, which thereby could enhance resistance to sanitation attempts. These findings highlight the importance of investigations concerning the antimicrobial deposition effect after cleaning procedures, which may encourage bacterial adhesion, especially of bacteria that have been previously exposed to chemical stresses.
authors.affiliation: IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Idalina
authors.initials: I
authors.lastname: Machado
authors.forename: Joana
authors.initials: J
authors.lastname: Graça
authors.forename: Ana Margarida
authors.initials: AM
authors.lastname: Sousa
authors.forename: Susana Patrícia
authors.initials: SP
authors.lastname: Lopes
authors.forename: Maria Olívia
authors.initials: MO
authors.lastname: Pereira
mesh_terms: D000222:Adaptation, Physiological; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001422:Bacterial Adhesion / Q000187:drug effects*; D001548:Benzalkonium Compounds / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D057219:Biofouling; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D001548:Benzalkonium Compounds