title: Cyclic-β-glucans of Rhizobium (Sinorhizobium) sp. strain NGR234 are required for hypo-osmotic adaptation, motility, and efficient symbiosis with host plants.
abstract: Cyclic-β-glucans (CβG) consist of cyclic homo-polymers of glucose that are present in the periplasmic space of many Gram-negative bacteria. A number of studies have demonstrated their importance for bacterial infection of plant and animal cells. In this study, a mutant of Rhizobium (Sinorhizobium) sp. strain NGR234 (NGR234) was generated in the cyclic glucan synthase (ndvB)-encoding gene. The great majority of CβG produced by wild-type NGR234 are negatively charged and substituted. The ndvB mutation abolished CβG biosynthesis. We found that, in NGR234, a functional ndvB gene is essential for hypo-osmotic adaptation and swimming, attachment to the roots, and efficient infection of Vigna unguiculata and Leucaena leucocephala.
authors.affiliation: Laboratoire de Biologie Moléculaire des Plantes Supérieures (LBMPS), Département de Biologie végétale, Sciences III, Université de Genève, Genève, Switzerland.
authors.forename: Jérémie
authors.initials: J
authors.lastname: Gay-Fraret
authors.forename: Silvia
authors.initials: S
authors.lastname: Ardissone
authors.forename: Kumiko
authors.initials: K
authors.lastname: Kambara
authors.forename: William J
authors.initials: WJ
authors.lastname: Broughton
authors.forename: William J
authors.initials: WJ
authors.lastname: Deakin
authors.forename: Antoine
authors.initials: A
authors.lastname: Le Quéré
mesh_terms: D000222:Adaptation, Physiological; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics; D003001:Cloning, Molecular; D003470:Culture Media / Q000737:chemistry; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics; D007887:Fabaceae / Q000382:microbiology; D005407:Flagella / Q000737:chemistry / Q000502:physiology; D005798:Genes, Bacterial; D049452:Green Fluorescent Proteins / Q000737:chemistry; D008124:Locomotion; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics; D009154:Mutation; D009995:Osmosis; D010641:Phenotype; D055170:Plant Root Nodulation; D011401:Promoter Regions, Genetic; D053204:Root Nodules, Plant / Q000382:microbiology*; D020579:Sinorhizobium / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D013559:Symbiosis; D014158:Transcription, Genetic; D047071:beta-Glucans / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D008565:Membrane Proteins; C089201:NdvB protein, Rhizobium meliloti; D047071:beta-Glucans; D049452:Green Fluorescent Proteins; C033744:beta-1,2-glucan