title: Rhizobium leguminosarum biovar viciae 3841, deficient in 27-hydroxyoctacosanoate-modified lipopolysaccharide, is impaired in desiccation tolerance, biofilm formation and motility.
abstract: The lipopolysaccharide (LPS) of the Gram-negative legume symbiont Rhizobium leguminosarum biovar viciae 3,841 contains several unique modifications, including the addition of a 27-hydroxyoctacosanoic acid (27OHC28 : 0), also termed the very long chain fatty acid (VLCFA), attached at the 2' position of lipid A. A transposon mutant that lacks expression of two putative 3-oxo-acyl [acyl-carrier protein] synthase II genes, fabF1 and fabF2, from the VLCFA biosynthetic cluster, was isolated and characterized. MS indicated that the lipid A of the mutant lacked the VLCFA modification, and sodium deoxycholate (DOC)-PAGE of the LPS indicated further structural alterations. The mutant was characteristically sensitive to several stresses that would be experienced in the soil environment, such as desiccation and osmotic stresses. An increase in the excretion of neutral surface polysaccharides was observed in the mutant. This mutant was also altered in its attachment to solid surfaces, and was non-motile, with most of the mutant cells lacking flagella. Despite the pleiotropic effects of the mutation, these mutants were still able to nodulate legumes and fix atmospheric nitrogen. This report emphasizes that a structurally intact VLCFA-containing lipid A is critical to cellular traits that are important for survival in the rhizosphere.
authors.affiliation: Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Vanderlinde
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA.
authors.forename: Artur
authors.initials: A
authors.lastname: Muszyński
authors.affiliation: Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.
authors.forename: Joe J
authors.initials: JJ
authors.lastname: Harrison
authors.affiliation: Department of Microbiology and Immunology, University of Western Ontario, London, ON N6A 5C1, Canada.
authors.forename: Susan F
authors.initials: SF
authors.lastname: Koval
authors.affiliation: Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada.
authors.forename: Dallas L
authors.initials: DL
authors.lastname: Foreman
authors.affiliation: Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.
authors.forename: Howard
authors.initials: H
authors.lastname: Ceri
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA.
authors.forename: Elmar L
authors.initials: EL
authors.lastname: Kannenberg
authors.affiliation: Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA.
authors.forename: Russell W
authors.initials: RW
authors.lastname: Carlson
authors.affiliation: Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada.
authors.forename: Christopher K
authors.initials: CK
authors.lastname: Yost
mesh_terms: D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase / Q000737:chemistry / Q000172:deficiency / Q000235:genetics; D001422:Bacterial Adhesion; D018441:Biofilms / Q000254:growth & development*; D004269:DNA, Bacterial / Q000235:genetics; D007887:Fabaceae / Q000382:microbiology; D005798:Genes, Bacterial; D006880:Hydroxy Acids / Q000737:chemistry / Q000378:metabolism*; D008050:Lipid A / Q000737:chemistry / Q000378:metabolism*; D013058:Mass Spectrometry; D009586:Nitrogen Fixation; D016961:Rhizobium leguminosarum / Q000502:physiology*; D055049:Salt Tolerance; D020539:Sequence Analysis, Protein; D013312:Stress, Physiological
chemical_list: D004269:DNA, Bacterial; D006880:Hydroxy Acids; D008050:Lipid A; C059845:27-hydroxyoctacosanoic acid; D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase