title: Biofilm formation on polystyrene in detached vs. planktonic cells of polyhydroxyalkanoate-accumulating Halomonas venusta.
abstract: Biofilm development is characterized by distinct stages of initial attachment, microcolony formation and maturation (sessile cells), and final detachment (dispersal of new, planktonic cells). In this work we examined the influence of polyhydroxyalkanoate (PHA) accumulation on bacterial surface properties and biofilm formation on polystyrene in detached vs. planktonic cells of an environmental strain isolated from microbial mats, Halomonas venusta MAT28. This strain was cultured either in an artificial biofilm in which the cells were immobilized on alginate beads (sessile) or as free-swimming (planktonic) cells. For the two modes of growth, conditions allowing or preventing PHA accumulation were established. Cells detached from alginate beads and their planktonic counterparts were used to study cell surface properties and cellular adhesion on polystyrene. Detached cells showed a slightly higher affinity than planktonic cells for chloroform (Lewis-acid) and a greater hydrophobicity (affinity for hexadecane and hexane). Those surface characteristics of the detached cells may explain their better adhesion on polystyrene compared to planktonic cells. Adhesion to polystyrene was not significantly different between H. venusta cells that had accumulated PHA vs. those that did not. These observations suggest that the surface properties of detached cells clearly differ from those of planktonic cells and that for at least the first 48 h after detachment from alginate beads H. venusta retained the capacity of sessile cells to adhere to polystyrene and to form a biofilm.
authors.affiliation: Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Barcelona, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Berlanga
authors.affiliation: Physical Chemistry Laboratory V, Faculty of Pharmacy, University of Barcelona, Spain.
authors.forename: Òscar
authors.initials: Ò
authors.lastname: Domènech
authors.affiliation: Laboratory of Molecular Microbiology and Antimicrobials, Department of Pathology and Experimental Therapeutics, Faculty of Medicine, University of Barcelona-IDIBELL, Barcelona, Spain.|Barcelona Knowledge Hub, Academia Europaea, Barcelona, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Guerrero
mesh_terms: D001422:Bacterial Adhesion; D018441:Biofilms; D020632:Halomonas / Q000254:growth & development / Q000502:physiology*; D010933:Plankton / Q000254:growth & development / Q000502:physiology*; D054813:Polyhydroxyalkanoates / Q000378:metabolism*; D011137:Polystyrenes / Q000032:analysis
chemical_list: D054813:Polyhydroxyalkanoates; D011137:Polystyrenes
keywords: Halomonas venusta MAT-28; PHA; adhesion on polystyrene; alginate beads; cell surface physicochemical characteristics