title: The evolution of biofilm-forming Wrinkly Spreaders in static microcosms and drip-fed columns selects for subtle differences in wrinkleality and fitness.
abstract: Experimental evolution studies are used to investigate bacterial adaptive radiation in simple microcosms. In the case of the Wrinkly Spreader, a class of biofilm-forming adaptive mutants of Pseudomonas fluorescens SBW25, the current paradigm is that they are only evolutionarily successful in static microcosms where they outcompete other lineages for O2 at the air-liquid interface. However, we have isolated Wrinkly Spreaders from drip-fed glass bead columns as an example of parallel evolution. These mutants are adaptive, with competitive fitness advantages on columns of 1.28-1.78. This might be explained by the enhanced attachment characteristically shown by Wrinkly Spreaders, allowing them to resist liquid flow through the column pore network. A comparison of column and static microcosm-isolated Wrinkly Spreaders showed that many aspects of wrinkleality, including colony reversion, microcosm growth, biofilm strength and attachment, as well as fitness in static microcosms, were significantly different within and between the two groups of mutants. These findings indicate that the two environments had selected for Wrinkly Spreaders with subtly differing degrees of wrinkleality and fitnesses, suggesting that aspects of the Wrinkly Spreader phenotype may have different relative values in static microcosms and drip-fed columns.
authors.affiliation: SIMBIOS Centre, School of Science, Engineering and Technology, Abertay University, Dundee DD1 1HP, UK.
authors.forename: Yvette C
authors.initials: YC
authors.lastname: Udall
authors.affiliation: SIMBIOS Centre, School of Science, Engineering and Technology, Abertay University, Dundee DD1 1HP, UK.
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Deeni
authors.affiliation: SIMBIOS Centre, School of Science, Engineering and Technology, Abertay University, Dundee DD1 1HP, UK.
authors.forename: Simona M
authors.initials: SM
authors.lastname: Hapca
authors.affiliation: SIMBIOS Centre, School of Science, Engineering and Technology, Abertay University, Dundee DD1 1HP, UK.
authors.forename: David
authors.initials: D
authors.lastname: Raikes
authors.affiliation: SIMBIOS Centre, School of Science, Engineering and Technology, Abertay University, Dundee DD1 1HP, UK a.spiers@abertay.ac.uk.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Spiers
mesh_terms: D000220:Adaptation, Biological / Q000235:genetics*; D001422:Bacterial Adhesion / Q000235:genetics; D001483:Base Sequence; D018441:Biofilms / Q000254:growth & development*; D005075:Biological Evolution; D004269:DNA, Bacterial / Q000235:genetics; D004777:Environment; D010641:Phenotype; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000254:growth & development*; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial
keywords: Pseudomonas; bacterial adaptation; experimental evolution; fitness