title: Siderophore cooperation of the bacterium Pseudomonas fluorescens in soil.
abstract: While social interactions play an important role for the evolution of bacterial siderophore production in vitro, the extent to which siderophore production is a social trait in natural populations is less clear. Here, we demonstrate that siderophores act as public goods in a natural physical environment of Pseudomonas fluorescens: soil-based compost. We show that monocultures of siderophore producers grow better than non-producers in soil, but non-producers can exploit others' siderophores, as shown by non-producers' ability to invade populations of producers when rare. Despite this rare advantage, non-producers were unable to outcompete producers, suggesting that producers and non-producers may stably coexist in soil. Such coexistence is predicted to arise from the spatial structure associated with soil, and this is supported by increased fitness of non-producers when grown in a shaken soil-water mix. Our results suggest that both producers and non-producers should be observed in soil, as has been observed in marine environments and in clinical populations.
authors.affiliation: ESI, Biosciences, University of Exeter, Penryn, Cornwall TR10 9FE, UK adem.lujan@gmail.com.
authors.forename: Adela M
authors.initials: AM
authors.lastname: Luján
authors.affiliation: ESI, Biosciences, University of Exeter, Penryn, Cornwall TR10 9FE, UK.
authors.forename: Pedro
authors.initials: P
authors.lastname: Gómez
authors.affiliation: ESI, Biosciences, University of Exeter, Penryn, Cornwall TR10 9FE, UK.
authors.forename: Angus
authors.initials: A
authors.lastname: Buckling
mesh_terms: D007501:Iron / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D017262:Siderophores / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology
chemical_list: D017262:Siderophores; D012987:Soil; D007501:Iron
keywords: Pseudomonas fluorescens; cooperation; natural environment; public goods; soil