title: Exometabolite niche partitioning among sympatric soil bacteria.
abstract: Soils are arguably the most microbially diverse ecosystems. Physicochemical properties have been associated with the maintenance of this diversity. Yet, the role of microbial substrate specialization is largely unexplored since substrate utilization studies have focused on simple substrates, not the complex mixtures representative of the soil environment. Here we examine the exometabolite composition of desert biological soil crusts (biocrusts) and the substrate preferences of seven biocrust isolates. The biocrust's main primary producer releases a diverse array of metabolites, and isolates of physically associated taxa use unique subsets of the complex metabolite pool. Individual isolates use only 13-26% of available metabolites, with only 2 out of 470 used by all and 40% not used by any. An extension of this approach to a mesophilic soil environment also reveals high levels of microbial substrate specialization. These results suggest that exometabolite niche partitioning may be an important factor in the maintenance of microbial diversity.
authors.affiliation: Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Baran
authors.affiliation: Climate and Ecosystems Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.|Department of Environmental Science, Policy and Management, University of California Berkeley, Berkeley, California 94720, USA.
authors.forename: Eoin L
authors.initials: EL
authors.lastname: Brodie
authors.affiliation: Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.|School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, Arizona 85287, USA.
authors.forename: Jazmine
authors.initials: J
authors.lastname: Mayberry-Lewis
authors.affiliation: School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, Arizona 85287, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Hummel
authors.affiliation: Climate and Ecosystems Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.|Molecular Cell Physiology Department, Faculty of Earth and Life Sciences, VU Amsterdam, de Boelelaan 1085, 1081HV Amsterdam, The Netherlands.
authors.forename: Ulisses Nunes
authors.initials: UN
authors.lastname: Da Rocha
authors.affiliation: Climate and Ecosystems Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.
authors.forename: Romy
authors.initials: R
authors.lastname: Chakraborty
authors.affiliation: Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.|DOE Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, California 94598, USA.
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Bowen
authors.affiliation: Climate and Ecosystems Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.
authors.forename: Ulas
authors.initials: U
authors.lastname: Karaoz
authors.affiliation: School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, Arizona 85287, USA.
authors.forename: Hinsby
authors.initials: H
authors.lastname: Cadillo-Quiroz
authors.affiliation: School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, Arizona 85287, USA.
authors.forename: Ferran
authors.initials: F
authors.lastname: Garcia-Pichel
authors.affiliation: Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, California 94720, USA.|DOE Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, California 94598, USA.
authors.forename: Trent R
authors.initials: TR
authors.lastname: Northen
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000378:metabolism*; D000458:Cyanobacteria / Q000145:classification; D003889:Desert Climate; D017753:Ecosystem; D012988:Soil Microbiology; D014589:Utah