title: Structural determination of the phytotoxic mannan exopolysaccharide from Pseudomonas syringae pv. ciccaronei.
abstract: The structural determination was performed of a mannan exopolysaccharide from the gram negative bacterium Pseudomonas syringae pv. ciccaronei, which is the pathogenic agent responsible for the leaf spots of carob plants. The structure, obtained by chemical, enzymatic and spectroscopic methods, consisted of a backbone of alpha-(1-->6)-linked mannopyranose units with 80% substituted at C-2 by mono-, di- and trisaccharide side chains. In addition, terminal glucose units and phosphate groups were found to be present. This is, to the best of our knowledge, the first report of a mannan exopolysaccharide structure from a phytopathogenic bacterium. The pure polysaccharide showed phytotoxic effects, i.e., chlorosis and necrosis on tobacco leaves.
authors.affiliation: Dipartimento di Chimica Organica e Biologica, Università di Napoli Federico II, Italy.
authors.forename: M M
authors.initials: MM
authors.lastname: Corsaro
authors.forename: A
authors.initials: A
authors.lastname: Evidente
authors.forename: R
authors.initials: R
authors.lastname: Lanzetta
authors.forename: P
authors.initials: P
authors.lastname: Lavermicocca
authors.forename: A
authors.initials: A
authors.lastname: Molinaro
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002850:Chromatography, Gel; D008351:Mannans / Q000737:chemistry* / Q000633:toxicity*; D008969:Molecular Sequence Data; D009336:Necrosis; D019906:Nuclear Magnetic Resonance, Biomolecular; D010935:Plant Diseases / Q000139:chemically induced / Q000382:microbiology; D010947:Plants, Toxic; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000494:pharmacology*; D011549:Pseudomonas / Q000737:chemistry; D014026:Nicotiana / Q000187:drug effects
chemical_list: D008351:Mannans; D011135:Polysaccharides, Bacterial; C064841:exopolysaccharide, Pseudomonas