title: Lipopolysaccharide and porin of Roseobacter denitrificans, confirming its phylogenetic relationship to the alpha-3 subgroup of Proteobacteria.
abstract: Roseobacter denitrificans has rough (R)-type lipopolysaccharide, containing 2-keto-3-deoxyoctonate but no hepatoses. Its lipid A has a glucosamine-containing, phosphorylated backbone. It contains the rare 3-oxotetradecanoic (3-oxomyristic) acid as the only amide-bound fatty acid and ester-bound 3-hydroxydecanoic acid, this pattern being characteristic for the alpha-3 subgroup of Proteobacteria. Treatment of the major outer-membrane protein (porin, apparent molecular mass 88 kDa) of Roseobacter denitrificans with EDTA (2 mM, 30 degrees C, 20 min) resulted in the dissociation of the oligomers into monomers (apparent molecular mass 35 kDa). EDTA-sensitive dissociation has so far been observed only within the alpha-3 subgroup of Proteobacteria. The 12 N-terminal amino acids of the monomers exhibit sequence homology with the porins of Rhodobacter capsulatus, Rhodobacter sphaeroides and Rhodopseudomonas blastica. Renaming of Roseobacter denitrificans as Rhodobacter denitrificans is suggested.
authors.affiliation: Institut für Biologie II, Mikrobiologie, Schänzlestraße 1, D-79104 Freiburg, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Neumann
authors.affiliation: Max Planck Institut für Immunbiologie, Stübeweg 51, D-79108 Freiburg, Germany.
authors.forename: Hubert
authors.initials: H
authors.lastname: Mayer
authors.affiliation: Institut für Organische Chemie und Biochemie, Albertstraße 21, D-79104 Freiburg, Germany.
authors.forename: Emile
authors.initials: E
authors.lastname: Schiltz
authors.affiliation: Lehrstuhl für Biotechnologie, Biozentrum der Universitat Würzburg, Am Hubland, D-97074 Würzburg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Benz
authors.affiliation: Institut für Biologie II, Mikrobiologie, Schänzlestraße 1, D-79104 Freiburg, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Weckesser
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D001419:Bacteria / Q000737:chemistry / Q000145:classification* / Q000235:genetics; D002241:Carbohydrates / Q000737:chemistry; D002845:Chromatography; D004591:Electrophoresis, Polyacrylamide Gel; D008401:Gas Chromatography-Mass Spectrometry; D006088:Gram-Negative Aerobic Bacteria / Q000737:chemistry / Q000145:classification* / Q000235:genetics; D008050:Lipid A / Q000737:chemistry; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010802:Phylogeny; D018272:Porins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D016992:Rhodobacter / Q000145:classification / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D008050:Lipid A; D008070:Lipopolysaccharides; D018272:Porins