title: Sinorhizobium fredii HH103 bacteroids are not terminally differentiated and show altered O-antigen in nodules of the Inverted Repeat-Lacking Clade legume Glycyrrhiza uralensis.
abstract: In rhizobial species that nodulate inverted repeat-lacking clade (IRLC) legumes, such as the interaction between Sinorhizobium meliloti and Medicago, bacteroid differentiation is driven by an endoreduplication event that is induced by host nodule-specific cysteine rich (NCR) antimicrobial peptides and requires the participation of the bacterial protein BacA. We have studied bacteroid differentiation of Sinorhizobium fredii HH103 in three host plants: Glycine max, Cajanus cajan and the IRLC legume Glycyrrhiza uralensis. Flow cytometry, microscopy analyses and viability studies of bacteroids as well as confocal microscopy studies carried out in nodules showed that S. fredii HH103 bacteroids, regardless of the host plant, had deoxyribonucleic acid (DNA) contents, cellular sizes and survival rates similar to those of free-living bacteria. Contrary to S. meliloti, S. fredii HH103 showed little or no sensitivity to Medicago NCR247 and NCR335 peptides. Inactivation of S. fredii HH103 bacA neither affected symbiosis with Glycyrrhiza nor increased bacterial sensitivity to Medicago NCRs. Finally, HH103 bacteroids isolated from Glycyrrhiza, but not those isolated from Cajanus or Glycine, showed an altered lipopolysaccharide. Our studies indicate that, in contrast to the S. meliloti-Medicago model symbiosis, bacteroids in the S. fredii HH103-Glycyrrhiza symbiosis do not undergo NCR-induced and bacA-dependent terminal differentiation.
authors.affiliation: Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, CP, 41012, Sevilla, Spain.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Crespo-Rivas
authors.affiliation: Institute for Integrative Biology of the Cell, Centre National de la Recherche Scientifique, UMR 9198, 91198, Gif-sur-Yvette, France.
authors.forename: Ibtissem
authors.initials: I
authors.lastname: Guefrachi
authors.affiliation: Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA.
authors.forename: Kenny C
authors.initials: KC
authors.lastname: Mok
authors.affiliation: Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, CP, 41012, Sevilla, Spain.|Institute for Integrative Biology of the Cell, Centre National de la Recherche Scientifique, UMR 9198, 91198, Gif-sur-Yvette, France.
authors.forename: José A
authors.initials: JA
authors.lastname: Villaécija-Aguilar
authors.affiliation: Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, CP, 41012, Sevilla, Spain.
authors.forename: Sebastián
authors.initials: S
authors.lastname: Acosta-Jurado
authors.affiliation: Institute for Integrative Biology of the Cell, Centre National de la Recherche Scientifique, UMR 9198, 91198, Gif-sur-Yvette, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Pierre
authors.affiliation: Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, CP, 41012, Sevilla, Spain.
authors.forename: José E
authors.initials: JE
authors.lastname: Ruiz-Sainz
authors.affiliation: Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA.
authors.forename: Michiko E
authors.initials: ME
authors.lastname: Taga
authors.affiliation: Institute for Integrative Biology of the Cell, Centre National de la Recherche Scientifique, UMR 9198, 91198, Gif-sur-Yvette, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Mergaert
authors.affiliation: Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, CP, 41012, Sevilla, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Vinardell
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D029882:Glycyrrhiza uralensis / Q000235:genetics / Q000382:microbiology* / Q000502:physiology; D055029:Inverted Repeat Sequences; D008070:Lipopolysaccharides / Q000378:metabolism; D019081:O Antigens / Q000235:genetics / Q000378:metabolism*; D053204:Root Nodules, Plant / Q000235:genetics / Q000382:microbiology* / Q000502:physiology; D042181:Sinorhizobium fredii / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D013559:Symbiosis
chemical_list: D001426:Bacterial Proteins; D008070:Lipopolysaccharides; D019081:O Antigens