title: The genomes of closely related Pantoea ananatis maize seed endophytes having different effects on the host plant differ in secretion system genes and mobile genetic elements.
abstract: The seed as a habitat for microorganisms is as yet under-explored and has quite distinct characteristics as compared to other vegetative plant tissues. In this study, we investigated three closely related P. ananatis strains (named S6, S7, and S8), which were isolated from maize seeds of healthy plants. Plant inoculation experiments revealed that each of these strains exhibited a different phenotype ranging from weak pathogenic (S7), commensal (S8), to a beneficial, growth-promoting effect (S6) in maize. We performed a comparative genomics analysis in order to find genetic determinants responsible for the differences observed. Recent studies provided exciting insight into the genetic drivers of niche adaption and functional diversification of the genus Pantoea. However, we report here for the first time on the analysis of P. ananatis strains colonizing the same ecological niche but showing distinct interaction strategies with the host plant. Our comparative analysis revealed that genomes of these three strains are highly similar. However, genomic differences in genes encoding protein secretion systems and putative effectors, and transposase/integrases/phage related genes could be observed.
authors.affiliation: Bioresources Unit, Health and Environment Department, AIT Austrian Institute of Technology GmbH Tulln, Austria ; Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna Vienna, Austria.
authors.forename: Raheleh
authors.initials: R
authors.lastname: Sheibani-Tezerji
authors.affiliation: Bioresources Unit, Health and Environment Department, AIT Austrian Institute of Technology GmbH Tulln, Austria.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Naveed
authors.affiliation: Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna Vienna, Austria.
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Jehl
authors.affiliation: Bioresources Unit, Health and Environment Department, AIT Austrian Institute of Technology GmbH Tulln, Austria.
authors.forename: Angela
authors.initials: A
authors.lastname: Sessitsch
authors.affiliation: Division of Computational System Biology, Department of Microbiology and Ecosystem Science, University of Vienna Vienna, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Rattei
authors.affiliation: Bioresources Unit, Health and Environment Department, AIT Austrian Institute of Technology GmbH Tulln, Austria.
authors.forename: Birgit
authors.initials: B
authors.lastname: Mitter
keywords: Pantoea ananatis; comparative genomics; plant growth promotion; seed endophyte