Structure of the O-specific polysaccharides of Pseudomonas chlororaphis subsp. chlororaphis UCM B-106.

O-specific polysaccharide was obtained from the lipopolysaccharide of Pseudomonas chlororaphis subsp. chlororaphis UCM B-106 and studied by composition analysis along with 1D and 2D (1)H and (13)C NMR spectroscopy. The polysaccharide was found to contain a derivative of pseudaminic acid (Pse) and the following structure of the trisaccharide repeating unit was established: →4)-ß-Psep5Ac7Hb-(2 â†’ 6)-ß-d-Galf-(1 â†’ 3)-ß-d-Galp-(1→ where Pse5Ac7Hb indicates 5-acetamido-3,5,7,9-tetradeoxy-7-[(R)-3-hydroxybutanoylamino]-l-glycero-l-manno-non-2-ulosonic acid.

Structure of the O-polysaccharide of the lipopolysaccharide of Pseudomonas chlororaphis subsp. aureofaciens UCM B-306.

Structure of the O-specific polysaccharide from Pseudomonas chlororaphis subsp. aureofaciens UCM B-306 was elucidated by sugar analysis along with 1D and 2D (1)H and (13)C NMR spectroscopy. The polysaccharide is built up of trisaccharide repeats containing D-rhamnose, 2,4-diacetamido-2,4,6-trideoxy-D-glucose (D-QuiNAc4NAc), and 2-acetamido-2-deoxy-D-galacturonic acid (D-GalNAcA), which is amidated in ∼40% repeats. It was suggested that the O-polysaccharide has a blockwise structure, which can be presented as follows: -[→3)-α-D-Rhap-(1→4)-α-D-GalpNAcA-(1→3)-α-D-QuipNAc4NAc-(1-]n→ and -[→3)-α-D-Rhap-(1→4)-α-D-GalpNAcAN-(1→3)-α-D-QuipNAc4NAc-(1-]m→, where GalNAcAN indicates 2-acetamido-2-deoxy-D-galacturonamide, n:m=∼3:2.

Pseudomonas brassicacearum subsp. neoaurantiaca subsp. nov., orange-pigmented bacteria isolated from soil and the rhizosphere of agricultural plants.

A large group of 38 strains of saprophytic bacteria was isolated from soil and the rhizosphere of agricultural plants. The novel organisms were Gram-negative, aerobic, rod-shaped bacteria that produced a green fluorescent pigment, a red-orange diffusible pigment and a complex mixture of phloroglucinol derivates with antimicrobial activity. The latter have not been found in other bacteria, but are peculiar to ferns. The bacteria were vigorous denitrifiers that synthesized levan from sucrose and liquefied gelatin, but were found not to degrade aesculin, starch, agar, Tween 80 or DNA. Bacterial growth was found to occur at 4 degrees C but not at 40 degrees C. The predominant cellular fatty acids were 16 : 0, 16 : 1(n-7), 18 : 1(n-7) and 17 : 0 cyclo. The G+C content of the novel bacteria was 61.0-62.9 mol%. 16S rRNA gene sequence analysis indicated that the representative strain CIP 109457(T) had a clear affiliation with Pseudomonas sensu stricto groups, with the nearest relatives being Pseudomonas brassicacearum, P. thivervalensis, P. corrugata, P. mediterranea and P. kilonensis. DNA-DNA hybridization experiments showed that the group of isolated strains exhibited high levels of genetic relatedness (81-100 %), confirming that they are representatives of the same species. At the same time, they bound at low levels (4-46 %) with DNA of the type strains of their nearest relatives with the exception of P. brassicacearum; DNA binding of 90 % with the DNA of P. brassicacearum CIP 107059(T) suggested that the bacteria studied belong to this species. Analysis of taxonomic data indicated that the group of novel bacteria maintain a distinct phenotypic profile, allowing the description of novel subspecies within P. brassicacearum, for which the following names are proposed: Pseudomonas brassicacearum subsp. brassicacearum subsp. nov. (type strain DBK11(T) =CFBP 11706(T) =CIP 107059(T) =DSM 13227(T) =JCM 11938(T)) and Pseudomonas brassicacearum subsp. neoaurantiaca subsp. nov., with the type strain CIP 109457(T) (=ATCC 49054(T) =IMV 387(T) =VKM B-1524(T)).

Oceanimonas smirnovii sp. nov., a novel organism isolated from the Black Sea.

A slightly creamy, melanogenic, gram-negative, aerobic bacterium was isolated from seawater sample collected in the Karadag Natural Reserve of the Eastern Crimea, the Black Sea. The novel organism was chemoorganotrophic, had no obligate requirement in NaCl, tolerated to 12% NaCl, grew between 10 and 45 degrees C, was slightly alkaliphilic, and was not able to degrade starch, gelatin, agar, and Tween 80. 16S rRNA gene sequence-based analyses of the new organism revealed that Oceanimonas doudoroffii ATCC 27123T, Oceanimonas baumanii ATCC 700832T, and Oceanisphaera litoralis DSM 15406T were the closest relatives (similarity around 97%-96%). The G + C content of the DNA of the strain 31-13T was 55.5mol%. Phosphatidylethanolamine (49.0%), phosphatidylglycerol (41.8%), and diphosphatidylglycerol (9.2%) were the predominant phospholipids. The major fatty acids were 16:0 (24.1%), 16:1omega7 (40.3%), and 18:1omega7 (29.2%). On the basis of the significant differences demonstrated in the phenotypic and chemotaxonomic characteristics, it is suggested that the bacterium be classified as a novel species; the name Oceanimonas smirnovii sp. nov. is proposed. The type strain is 31-13T (UCM B-11076T = LMG 22147T = ATCC BAA-899T).

Marinomonas pontica sp. nov., isolated from the Black Sea.

A Gram-negative, polarly flagellated bacterium was isolated from a sea-water sample collected from the Karadag Natural Reserve of the Eastern Crimea and characterized to clarify its taxonomic position. 16S rRNA gene sequence-based phylogenetic analysis of this novel organism revealed Marinomonas vaga, Marinomonas communis, Marinomonas mediterranea, Marinomonas primoryensis and 'Marinomonas protea' as its closest relatives (similarity 95-97 %). The G+C content of the DNA was 46.5 mol%. The organism grew between 4 and 33 degrees C, tolerated 10 % NaCl, was slightly alkaliphilic and was not able to degrade starch, gelatin, agar or Tween 80. Phosphatidylethanolamine (53.4 %) and phosphatidylglycerol (46.6 %) were the predominant phospholipids. The major fatty acids were 16 : 0 (15.5 %), 16 : 1omega7 (26.7 %) and 18 : 1omega7 (47.1 %). The phylogenetic, genetic and physiological properties of the organism placed it within a novel species, proposed as Marinomonas pontica sp. nov., the type strain of which is 46-16T (=LMG 22531T=KMM 3492T=UCM 11075T).