title: Individual Members of the Microbiota Disproportionately Modulate Host Innate Immune Responses.
abstract: Predicting host health status based on microbial community structure is a major goal of microbiome research. An implicit assumption of microbiome profiling for diagnostic purposes is that the proportional representation of different taxa determine host phenotypes. To test this assumption, we colonized gnotobiotic zebrafish with zebrafish-derived bacterial isolates and measured bacterial abundance and host neutrophil responses. Surprisingly, combinations of bacteria elicited immune responses that do not reflect the numerically dominant species. These data are consistent with a quantitative model in which the host responses to commensal species are additive but where various species have different per capita immunostimulatory effects. For example, one species has a high per capita immunosuppression that is mediated through a potent secreted factor. We conclude that the proportional representation of bacteria in a community does not necessarily predict its functional capacities; however, characterizing specific properties of individual species offers predictive insights into multi-species community function.
authors.affiliation: Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA.
authors.forename: Annah S
authors.initials: AS
authors.lastname: Rolig
authors.affiliation: Department of Physics, University of Oregon, Eugene, OR 97403, USA.
authors.forename: Raghuveer
authors.initials: R
authors.lastname: Parthasarathy
authors.affiliation: Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA.
authors.forename: Adam R
authors.initials: AR
authors.lastname: Burns
authors.affiliation: Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA.
authors.forename: Brendan J M
authors.initials: BJ
authors.lastname: Bohannan
authors.affiliation: Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA. Electronic address: guillemin@molbio.uoregon.edu.
authors.forename: Karen
authors.initials: K
authors.lastname: Guillemin
mesh_terms: D000333:Aeromonas / Q000276:immunology; D000818:Animals; D005856:Germ-Free Life; D007114:Immunization; D064307:Microbiota; D023421:Models, Animal; D008954:Models, Biological; D009504:Neutrophils / Q000276:immunology*; D020592:Shewanella / Q000276:immunology; D013559:Symbiosis; D014733:Vibrio / Q000276:immunology; D015027:Zebrafish / Q000276:immunology* / Q000382:microbiology