title: Selection of hyperadherent mutants in Pseudomonas putida biofilms.
abstract: A number of genetic determinants required for bacterial colonization of solid surfaces and biofilm formation have been identified in different micro-organisms. There are fewer accounts of mutations that favour the transition to a sessile mode of life. Here we report the isolation of random transposon Pseudomonas putida KT2440 mutants showing increased biofilm formation, and the detailed characterization of one of them. This mutant exhibits a complex phenotype, including altered colony morphology, increased production of extracellular polymeric substances and enhanced swarming motility, along with the formation of denser and more complex biofilms than the parental strain. Sequence analysis revealed that the pleiotropic phenotype exhibited by the mutant resulted from the accumulation of two mutations: a transposon insertion, which disrupted a predicted outer membrane lipoprotein, and a point mutation in lapG, a gene involved in the turnover of the large adhesin LapA. The contribution of each alteration to the phenotype and the possibility that prolonged sessile growth results in the selection of hyperadherent mutants are discussed.
authors: Center for Systems Microbiology, Technical University of Denmark, Lyngby, Denmark.|Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain.
authors: Fátima
authors: F
authors: Yousef-Coronado
authors: Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain.
authors: María Isabel
authors: MI
authors: Soriano
authors: Center for Systems Microbiology, Technical University of Denmark, Lyngby, Denmark.
authors: Liang
authors: L
authors: Yang
authors: Center for Systems Microbiology, Technical University of Denmark, Lyngby, Denmark.
authors: Søren
authors: S
authors: Molin
authors: Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Granada, Spain.
authors: Manuel
authors: M
authors: Espinosa-Urgel