Erythrobacter vulgaris sp. nov., a novel organism isolated from the marine invertebrates.

Four yellow-pigmented, gram-negative, chemoorganotrophic aerobic bacteria were isolated from starfish Stellaster equestris (strains 022-2-10T, 022-2-9, and 022-2-12) and soft coral (unidentified species) (strain 022-4-7) collected in the South China Sea. 16S rRNA gene sequence-based analyses of the new organisms revealed that Erythrobacter spp. were the closest relatives and shared the highest similarity of 98.7% to E. citreus, 98.5% to E. flavus, 97.9% to E. litoralis and 97.6% to E. longus. The novel organisms were tolerant to 3-6% NaCl, grew between 10 degrees C and 40 degrees C, and were not able to degrade gelatin, casein, and agar, while degraded Tween 80. Two strains (022-2-9 and 022-2-12) could weakly degrade starch. All strains produced a large pool of carotenoids and did not have Bacteriochlorophyll a. Phosphatidylethanolamine (30-36%), phosphatidylglycerol (39-46%), and phosphatidylcholine (21-27%) were the predominant phospholipids. Sphingoglycolipid was not detected. The major fatty acids were 16:0 (6-11%), 16:1omega7 (12-15%), and 18:1omega7 (46-49%). The two-hydroxy fatty acids, 13:0-2OH, 14:0-2OH, 15:0-2OH, 16:0-2OH were also present. The G + C content of the DNAs ranged from 61 to 62 mol%. The level of DNA similarity among four strains was conspecific and ranged from 94% to 98%. Even though new strains and other species of the genus had rather high level of 16S rRNA gene sequence similarities, DNA-DNA hybridization experiments showed only 33-39% of binding with the DNA of the type strains. On the basis of these results and the significant differences demonstrated in the phenotypic and chemotaxonomic characteristics, it is suggested that the new organisms be classified as a novel species; the name Erythrobacter vulgaris sp. nov. is proposed. The type strain is 022-2-10T (= KMM 3465T = CIP 107841T).

Occurrence and diversity of mesophilic Shewanella strains isolated from the North-West Pacific Ocean.

Although bacteria of the genus Shewanella belong to one of the readily cultivable groups of "Gammaproteobacteria", little is known about the occurrence and abundance of these microorganisms in the marine ecosystem. Studies revealed that of 654 isolates obtained from marine invertebrates (ophiuroid Amphiopholis kochii, sipuncula Phascolosoma japonicum, and holothurian Apostichopus japonicus, Cucumaria japonica), seawater and sediments of the North-West Pacific Ocean (i.e. the Sea of Japan and Iturup Is, Kurile Islands), 10.7% belonged to the genus Shewanella. The proportion of viable Shewanella species varied from 4% to 20% depending on the source of isolation. From the isolation study, representative strains of different phenotypes (from seventy presumptive Shewanella strains) were selected for detailed characterization using phenotypic, chemotaxonomic, and phylogenetic testing. 16S rDNA sequence-based phylogenetic analysis confirmed the results of tentative identification and placed the majority of these strains within only a few species of the genus Shewanella with 98-99% of 16S rDNA sequences identity mainly with S. japonica and S. colwelliana, suggesting that the strains studied might belong to these species. Numerically dominant strains of S. japonica were metabolically active and produced proteinases (gelatinases, caseinases), lipases, amylases, agarases, and alginases. Shewanella strains studied demonstrated weak antimicrobial and antifungal activities that might be an indication of their passive role in the colonization on living and non-living surfaces.

Winogradskyella exilis sp. nov., isolated from the starfish Stellaster equestris, and emended description of the genus Winogradskyella.

A pale-yellowish-pigmented strain, 022-2-26(T), was isolated from a starfish, Stellaster equestris. Cells of strain 022-2-26(T) were Gram-negative short rods that were chemo-organotrophic, alkalitolerant and mesophilic. The predominant menaquinone was MK-6. The major cellular fatty acids were iso-C(15 : 0), iso-C(15 : 1), C(15 : 0), iso-C(15 : 0) 2-OH and iso-C(17 : 0) 3-OH (together representing 87 % of the total fatty acids). The DNA G+C content was 30.1 mol%. A 16S rRNA gene sequence of the isolate was determined and phylogenetic analyses revealed that strain 022-2-26(T) formed a robust clade (neighbour-joining algorithm with a bootstrap value of 95 % and parsimony and maximum-likelihood algorithms) with type strains of species in the genus Winogradskyella. The closest phylogenetic neighbour of strain 022-2-26(T) was Winogradskyella poriferorum UST030701-295(T) (96 % 16S rRNA gene sequence similarity; 59 differences between sequences). On the basis of the phenotypic and chemotaxonomic characteristics and the phylogenetic evidence, it is proposed that strain 022-2-26(T) represents a novel species, Winogradskyella exilis sp. nov. The type strain is 022-2-26(T) (=KMM 6013(T) =CIP 109976(T)).

Loktanella agnita sp. nov. and Loktanella rosea sp. nov., from the north-west Pacific Ocean.

One whitish and four pinkish strains of Gram-negative, non-motile, aerobic bacteria were isolated from sea-water and sediment samples collected in Chazhma Bay (Sea of Japan, Pacific Ocean). Analysis of 16S rRNA gene sequences revealed that these strains belonged to the 'Alphaproteobacteria', having highest sequence similarity of about 94-97% with species of the genus Loktanella. None of the strains degraded gelatin, casein, chitin, agar, DNA or starch and they had limited ability to utilize carbon sources. The four pinkish strains, Fg36(T), Fg1, Fg116 and Fg117, degraded Tween 80. Sea-water strain R10SW5(T) grew at 3-6% NaCl and a temperature range of 8-35 degrees C, whilst strains Fg36(T), Fg1, Fg116 and Fg117 grew at NaCl concentrations of 1-12% and a temperature range of 4-35 degrees C. Phosphatidylglycerol (58/79%), diphosphatidylglycerol (11/6%) and phosphatidylcholine (28/22%) were the major phospholipids. The predominant fatty acids were 16:0 (12.2/8.6%) and 18:1omega7 (76.6/68.4%). The DNA G+C content of strain R10SW5(T) was 59.1 mol% and those of the four pinkish strains ranged from 60.5 to 61.8 mol%. Based on the results of phenotypic, genotypic, chemotaxonomic and phylogenetic investigation, two novel species, Loktanella agnita sp. nov. and Loktanella rosea sp. nov., are proposed. The type strains are R10SW5(T) (=KMM 3788(T)=CIP 107883(T)) and Fg36(T) (=KMM 6003(T)=CIP 107851(T)=LMG 22534(T)), respectively.

Alteromonas addita sp. nov.

On the basis of phenotypic, genotypic characteristics and analysis of 16S rRNA gene sequences, a novel species belonging to the genus Alteromonas is described. A non-pigmented, motile, Gram-negative bacterium designated R10SW13(T) was isolated from sea water samples collected in Chazhma Bay (Sea of Japan, Pacific Ocean). The novel organism mainly grew between 4 degrees C and 37 degrees C, was neutrophilic and slightly halophilic, tolerating up to 10 % NaCl. Strain R10SW13(T) was haemolytic and was able to degrade starch and Tween 80 and to degrade gelatin and agar weakly, but did not degrade casein. Phosphatidylethanolamine (44.3 +/- 0.9 %) and phosphatidylglycerol (55.7 +/ -0.9 %) were the predominant phospholipids. The major fatty acids formed were typical for the genus Alteromonas, including 16 : 0, 16 : 1omega-7 and 18 : 1omega-7. The G + C content of the DNA was 43.4 mol%. DNA-DNA hybridization experiments showed 38-53 % binding with the DNAs of type strains of phylogenetically related species of the genus Alteromonas, namely: Alteromonas macleodii, Alteromonas marina, Alteromonas stellipolaris, Alteromonas litorea, 'Alteromonas macleodii subsp. fijiensis' and 'Alteromonas infernus'. Based on these results, a novel species, Alteromonas addita sp. nov., is proposed, with strain R10SW13(T) (=KMM 3600(T) = KCTC 12195(T) = LMG 22532(T)) as the type strain.

Shewanella pacifica sp. nov., a polyunsaturated fatty acid-producing bacterium isolated from sea water.

Six marine bacterial strains, KMM 3597T, KMM 3775, KMM 3590, KMM 3772, KMM 3605 and KMM 3601, that produce polyunsaturated fatty acids were isolated from sea water samples collected from different locations and depths in Chazhma Bay (Sea of Japan, Pacific Ocean) and characterized to clarify their taxonomic position. The DNA G+C contents of these strains were 39.5-40.3 mol%. The level of DNA hybridization between these strains was conspecific (83-96%), indicating that they represent a single genospecies. 16S rRNA gene sequence-based phylogenetic analysis of the novel strains revealed that Shewanella japonica KMM 3299T was the closest relative (99% similarity). However, DNA-DNA hybridization experiments demonstrated only 45-50% binding with DNA of S. japonica. The novel organisms grew between 4 and 33 degrees C, were neutrophilic and haemolytic, and were able to degrade starch, gelatin, agar and Tween 80. The predominant fatty acids were (%+/-sd): i13 : 0 (9.3+/-1.1); i15 : 0 (33.9+/-1.5); 16 : 0 (8.9+/-1.6); and 16 : 1omega7 (14.8+/-1.1). The fatty acid 20 : 5omega3, formed at 28 degrees C, was present at up to 5.3% total fatty acids. The major isoprenoid quinones were Q7 (21-41%) and Q8 (50-59%). The phylogenetic, genetic and physiological properties of the six strains placed them within a novel species, Shewanella pacifica sp. nov., the type strain of which is R10SW1T (=KMM 3597T=CIP 107849T).

Shewanella fidelis sp. nov., isolated from sediments and sea water.

Two marine bacterial strains, KMM 3582T and KMM 3589, isolated respectively from sediments of the South China Sea and sea water of the Sea of Japan, have been characterized. Comparative 16S rDNA sequence-based phylogenetic analysis placed the two strains in a separate branch of the gamma-Proteobacteria within the members of the genus Shewanella. KMM 3582T showed the highest similarity (97.1 and 97.4%, respectively) to Shewanella pealeana and Shewanella gelidimarina. The G + C contents of the DNAs of the two strains studied were 45.0 mol%. The level of DNA-DNA relatedness between the two strains was 82%, indicating that they represent a single genospecies. These organisms were slightly pinkish, Gram-negative, polarly flagellated, facultatively anaerobic, mesophilic (with temperature range from 4 to 30 degrees C), neutrophilic and haemolytic and were able to degrade alginate, gelatin and DNA. The novel organisms were susceptible to gentamicin, lincomycin, oleandomycin, streptomycin and polymyxin. The predominant fatty acids were characteristic for shewanellae: 13 : 0-i, 15 : 0-i, 16 : 0 and 16 : 1omega7. Eicosapentaenoic acid, 20 : 5omega3, was not detected. Phylogenetic evidence, together with phenotypic characteristics, showed that the two bacteria constitute a novel species of the genus Shewanella. The name Shewanella fidelis sp. nov. is proposed, with the type strain KMM 3582T (=LMG 20551T =ATCC BAA-318T).

Low-molecular-weight, biologically active compounds from marine Pseudoalteromonas species.

We have examined the ability of marine Proteobacteria from the Pseudoalteromonas genus and Alteromonas macleodii to produce low-molecular-weight, biologically active compounds with antimicrobial and surface-active properties. A new marine bacterium, Pseudoalteromonas issachenkonii, exhibited a high level of biological activity and produced antifungal and hemolytic compounds. A detailed spectroscopic investigation based on UV, IR, high-resolution mass spectrometry, and 2D 1H and 13C nuclear magnetic resonance revealed that the former was indole-2,3-dione (isatin). The chemical structure of red-brown pigment (C9H7N3OS3) responsible for hemolytic activity remained unclear. Four of the 15 strains studied (P. luteoviolacea, P. rubra, P. undina, and P. issachenkonii) produced cell-bound, two (P. elaykovii and P. carrageenovora) produced extracellular, and one strain (P. citrea) produced cell-bound and extracellular fatty acids and phospholipids with surface activity. Neither peptides nor glycolipids with surface activity were detected.

Pseudoalteromonas translucida sp. nov. and Pseudoalteromonas paragorgicola sp. nov., and emended description of the genus.

On the basis of phenotypic and genotypic characteristics and analysis of 16S rRNA sequences, two novel species belonging to the genus Pseudoalteromonas are described. A pale-orange-pigmented strain, KMM 3548T, isolated from a sponge and a non-pigmented strain, KMM 520T, isolated from sea water are marine, gram-negative, aerobic, rod-shaped organisms. One of the strains, KMM 520T, had bipolar flagella. Both strains had the ability to degrade gelatin, DNA and Tween 80 but not chitin or agar. Strain KMM 520T decomposed elastin and grew at NaCl concentrations of 1-8%, while strain KMM 3548T grew at 1-6% NaCl. The temperature range for both strains was 4-30 degrees C. The DNA G+C contents were 46.3 (KMM 520T) and 41.1 mol% (KMM 3548T). The level of DNA relatedness between the two strains was 20%. DNA from strain KMM 520T showed 8-34% genetic relatedness and that of KMM 3548T showed 17-53% relatedness to the DNA of other type strains of the genus Pseudoalteromonas. 16S rRNA analysis indicated a clear affiliation of these novel bacteria with the genus Pseudoalteromonas. The type strains of the novel species are Pseudoalteromonas translucida sp. nov. KMM 520T (= LMG 19696T = ATCC BAA-3157T) and Pseudoalteromonas paragorgicola sp. nov. KMM 3548T (= LMG 19694T = ATCC BAA-322T).

Pseudoalteromonas issachenkonii sp. nov., a bacterium that degrades the thallus of the brown alga Fucus evanescens.

Eleven non-pigmented strains of gram-negative, aerobic, marine bacteria with polar flagella were isolated from the thallus of the brown alga Fucus evanescens collected in the Kraternaya Bight of the Kurile Islands in the Pacific Ocean. These organisms were conspecific and exhibited high levels of genetic relatedness (up to 91%). The G+C contents of the DNAs of these strains were 42.9-43.3 mol%. These halophilic bacteria had bacteriolytic, proteolytic and haemolytic activities and degraded algal polysaccharides, synthesizing a number of glycoside hydrolases (fucoidanases, laminaranases, alginases, agarases, pullulanases, beta-glucosidases, beta-galactosidases, beta-N-acetylglucosaminidases and beta-xylosidases). By 16S rDNA analysis, the bacteria were shown to belong to the genus Pseudoalteromonas, a member of the gamma-subclass of the Proteobacteria. DNA from the strains isolated from the brown alga showed 27-54% genetic relatedness with respect to DNAs of other type strains of the genus Pseudoalteromonas. The phenotypic characteristics, together with the genetic evidence, indicate that this group of epiphytic bacteria represents a distinct species, Pseudoalteromonas issachenkonii sp. nov., for which the type strain is KMM 3549T (= LMG 19697T = CIP 106858T).

Pseudoalteromonas maricaloris sp. nov., isolated from an Australian sponge, and reclassification of [Pseudoalteromonas aurantia] NCIMB 2033 as Pseudoalteromonas flavipulchra sp. nov.

A marine, gram-negative, aerobic bacterium that produced cytotoxic, lemon-yellow, chromopeptide pigments that inhibited the development of sea urchin eggs has been isolated from the Australian sponge Fascaplysinopsis reticulata Hentschel. The cells of the organism were rod-shaped with a single polar flagellum and they required NaCl for growth (0.5-10%) with optimum growth at 1-3% NaCl. The temperature for growth was 10-37 degrees C, with optimum growth at 25-30 degrees C. Growth occurred at pH values from 6.0 to 10.0, with optimum growth at pH 6.0-8.0. Major phospholipids were phosphatidylethanolamine, phosphatidylglycerol and lyso-phosphatidylethanolamine. Of 26 fatty acids with 11-19 carbon atoms that were detected, 16:1omega7, 16:0, 17:1omega8 and 18:1omega7 were predominant. The DNA G+C content was 38.9 mol%. All of these phenotypic and chemotaxonomic characters place the organism in the genus Pseudoalteromonas (Gauthier et al, 1995). These data are consistent with the phylogenetic analyses that confirmed that strain KMM 636T is a member of the Pseudoalteromonas cluster in the gamma-subclass of the Proteobacteria. DNA-DNA hybridization experiments revealed that the levels of relatedness between the DNA of the strain studied and DNAs of type strains of the species that clustered together (on the basis of 16S rDNA sequences) and [Pseudoalteromonas aurantia] NCIMB 2033 ranged from 19 to 35%, and that the DNA-DNA homology between [P. aurantia] NCIMB 2033 and other phylogenetically and/or phenotypically similar type strains ranged from 32 to 52%. According to the polyphasic evidence presented in this study, it is proposed that strain KMM 636T (= LMG 19692T = CIP 106859T) be classified as Pseudoalteromonas maricaloris sp. nov. and [P. aurantia] NCIMB 2033 be reclassified as Pseudoalteromonas flavipulchra NCIMB 2033T (= KMM 3630T = LMG 20361T) sp. nov.

Marinobacter excellens sp. nov., isolated from sediments of the Sea of Japan.

Five strains of halophilic, Gram-negative marine bacteria (KMM 3809(T), KMM 3814, KMM 3815, KMM 3817 and KMM 3818) were isolated from sediments collected from Chazhma Bay, Sea of Japan. Phylogenetic 16S rRNA gene sequence-based analysis placed these bacteria in a clade within the genus Marinobacter in the gamma-Proteobacteria. KMM 3809(T) showed highest 16S rRNA gene sequence similarity of 97.3 % to Marinobacter litoralis and 96.9 % to Marinobacter hydrocarbonoclasticus and Marinobacter aquaeolei. DNA-DNA hybridization between the five isolates was at the conspecific level (94-96 %) and that among the closest phylogenetic neighbours ranged from 45.0 to 62.5 %. The new organisms were susceptible to polymyxin. Predominant fatty acids were C(16 : 0), C(16 : 1)omega9c, C(16 : 1)omega7c and C(18 : 1)omega9c. Phylogenetic evidence, along with phenotypic and genotypic characteristics, showed that the bacteria constituted a novel species of the genus Marinobacter. The name Marinobacter excellens sp. nov. is proposed for this species, with the type strain KMM 3809(T) (=CIP 107686(T)).

Tolerance to cadmium of free-living and associated with marine animals and eelgrass marine gamma-proteobacteria.

The tolerance to Cd2+ and possible mechanisms of Cd2+ detoxification by 178 free-living bacteria isolated from sea water, associated with marine animals (a mussel Crenomytilus grayanus, a scallop Patinopecten yessoensis), and eelgrass Zostera marina collected in The Sea of Japan and The Sea of Okhotsk have been studied. The concentrations of 25 and 50 mg Cd2+/L were highly toxic and inhibited the growth from 54% to 78% of the total bacteria studied. The free-living bacteria isolated from seawater samples (up to 50%) were tolerant to high concentrations of cadmium. Marine gamma-proteobacteria tolerated Cd2+ by the activation of different detoxifying mechanisms. The strain Halomonas sp. KMM 734 isolated from seawater prevented the uptake of Cd2+ into bacterial cells. The chromosomal cadmium resistance system of Pseudoalteromonas citrea KMM 461 and Marinobacter sp. KMM 181 was found to be similar to class III metallothioneins (also known as phytochelatins).

Sulfitobacter delicatus sp. nov. and Sulfitobacter dubius sp. nov., respectively from a starfish (Stellaster equestris) and sea grass (Zostera marina).

On the basis of data from phenotypic and genotypic characterization and analysis of 16S rRNA gene sequences, two novel species belonging to the genus Sulfitobacter are described. Strains KMM 3584(T), a pale-yellowish, non-motile strain isolated from a starfish (Stellaster equestris), and KMM 3554(T), which is motile by means of a single subpolar flagellum and was isolated from sea grass (Zostera marina), are marine, Gram-negative, aerobic, rod-shaped organisms. Both strains have the ability to degrade gelatin, but not casein, chitin, agar, DNA, Tween 80 or starch. Strain KMM 3584(T) decomposed alginate and grew at NaCl concentrations of 1-8 % and temperatures of 12-37 degrees C, whereas strain KMM 3554(T) grew in 1-12 % NaCl and at temperatures of 10-30 degrees C. The predominant fatty acid was 18 : 1omega7, amounting to up to 80 % of the total fatty acids. The other characteristic feature was the presence of 18 : 2 isomers. The DNA G+C contents of KMM 3584(T) and KMM 3554(T) were respectively 60.0 and 63.7 mol%. The level of DNA similarity between the two strains was 33 %. DNA from KMM 3584(T) and KMM 3554(T) had hybridization values of 5-24 % and 10-41 %, respectively, with DNA from the type strains of Sulfitobacter pontiacus, Sulfitobacter brevis, Sulfitobacter mediterraneus and Staleya guttiformis. It is proposed that strains KMM 3584(T) (=LMG 20554(T)=ATCC BAA-321(T)) and KMM 3554(T) (=LMG 20555(T)=ATCC BAA-320(T)) represent two novel species, Sulfitobacter delicatus sp. nov. and Sulfitobacter dubius sp. nov., respectively.

Characterization of Pseudoalteromonas distincta-like sea-water isolates and description of Pseudoalteromonas aliena sp. nov.

Seven melanogenic Pseudoalteromonas distincta-like strains, KMM 3562T, KMM 3536, KMM 3537, KMM 3538, KMM 3539, KMM 3615 and KMM 3629, which expressed tyrosinases were isolated from sea-water samples collected from different locations in Amursky Bay (Sea of Japan, Pacific Ocean) and characterized to clarify their taxonomic position. By 16S rRNA gene sequence analysis, the bacteria were shown to belong to the genus Pseudoalteromonas. The G + C content of the DNAs of the strains was 41-43 mol%. The level of DNA similarity among these strains was conspecific (92-97 %), indicating that they represented a single genospecies. However, DNA from the strains isolated from sea water showed only 63-65 % genetic relatedness with the DNA of the type strain P. distincta. The novel organisms grew mainly between 4 and 30 degrees C, were neutrophilic and slightly halophilic (four strains had a narrow range of growth between 3 and 6 % NaCl, w/v), were haemolytic and cytotoxic and were able to degrade starch, gelatin and Tween 80. The predominant fatty acids, including 16 : 0, 16 : 1omega7, 17 : 1omega7 and 18 : 1omega7, were typical of the genus Pseudolateromonas. The phylogenetic, genetic and physiological properties of the seven strains placed them within a novel species, Pseudoalteromonas aliena sp. nov., the type strain of which is SW19T (= KMM 3562T = LMG 22059T).

Ecophysiological variabilities in ectohydrolytic enzyme activities of some Pseudoalteromonas species, P. citrea, P. issachenkonii, and P. nigrifaciens.

The ecophysiological variabilities in the ectohydrolytic enzyme profiles of the three species of Pseudoalteromonas, P. citrea, P. issachenkonii, and P. nigrifaciens, have been investigated. Forty-one bacteria isolated from several invertebrates, macroalgae, sea grass, and the surrounding water exhibited different patterns of hydrolytic enzyme activities measured as the hydrolysis of either native biopolymers or fluorogenic substrates. The activities of the following enzymes were assayed: proteinase, tyrosinase, lipase, amylase, chitinase, agarase, fucoidan hydrolase, laminaranase, alginase, pustulanase, cellulase, beta-glucosidase, alpha- and beta-galactosidases, beta-N-acetylglucosaminidase, beta-glucosaminidase, beta-xylosidase, and alpha-mannosidase. The occurrence and cell-specific activities of all enzymes varied over a broad range (from 0 to 44 micromol EU per hour) and depended not only on taxonomic affiliation of the strain, but also on the source/place of its isolation. This suggests 'specialization' of different species for different types of polymeric substrates as, for example, all strains of P. citrea and P. issachenkonii hydrolyzed alginate and laminaran, while strains of P. nigrifaciens were lacking the ability to hydrolyze most of the algal polysaccharides. The incidence of certain enzymes such as fucoidan hydrolases, alginate lyases, agarases, and alpha-galactosidases might be strain specific and reflect its particular ecological habitat.

Pseudoalteromonas ruthenica sp. nov., isolated from marine invertebrates.

On the basis of phenotypic and genotypic characteristics and analysis of 165 rRNA sequences, a novel species belonging to the genus Pseudoalteromonas is described. Two pale-orange-pigmented strains, KMM 300T and KMM 290, isolated respectively from a mussel, Crenomytilus grayanus, and a scallop, Patinopecten yessoensis, are marine, gram-negative, aerobic, rod-shaped bacteria that produce a number of antimicrobial compounds. The strains are able to degrade gelatin, elastin, starch, DNA and Tween 80. Chitin and agar are not degraded. The isolates from marine invertebrates grew at NaCl concentrations of 1-9% and a temperature range of 10-35 degrees C and did not utilize most of the wide range of carbohydrates tested, with the exception of D-glucose, cellobiose and sucrose. The DNA G+C content was 48.4-48.9 mol%. The level of DNA homology of the two strains was 98%. DNA from the strains isolated from marine invertebrates showed 5-15% genetic relatedness to the DNA of other type strains of the genus Pseudoalteromonas. 16S rRNA analysis indicated a clear affiliation of the novel bacteria to other species of the genus. The strains are assigned to a novel species, Pseudomonas ruthenica sp. nov., with the type strain KMM 300T (= LMG 19699T = CIP 106857T).

Pseudomonas extremorientalis sp. nov., isolated from a drinking water reservoir.

On the basis of phenotypic and genotypic characteristics and 16S rDNA sequence analysis, a novel species belonging to the genus Pseudomonas sensu stricto was identified. The saprophytic, fluorescent bacterium, designated KMM 3447(T), was isolated from a drinking water reservoir near Vladivostok City, Russia. The novel organism was a Gram-negative, aerobic, rod-shaped bacterium that produced a cyclic depsipeptide with surface-active properties. It degraded casein, but did not degrade gelatin, starch, agar or Tween 80. The bacterium was also haemolytic. Growth of the novel bacterium occurred between 4 and 35 degrees C. The predominant cellular fatty acids of the novel pseudomonad were C16:0, C16:1(n-7), C18:1(n-7) and C17.0 cyclo; branched fatty acids were only found in trace amounts. The G+C content of the novel bacterium was 61.0 mol%. 16S rDNA sequence analysis indicated that the novel bacterium had a clear affiliation with Pseudomonas fluorescens and species closely related to this recognized pseudomonad. DNA-DNA hybridization experiments showed that the novel bacterium bound at low levels (27-53%) with the DNA of the type strains of its nearest phylogenetic relatives, namely Pseudomonas tolaasii, Pseudomonas veronii, Pseudomonas orientalis and Pseudomonas rhodesiae, indicating that the novel bacterium represented a novel species within the genus Pseudomonas, for which the name Pseudomonas extremorientalis is proposed; the type strain is KMM 3447(T) (= LMG 19695(T)).