<Emphasis Type="Italic">Singulispaera mucilagenosa</Emphasis> sp. nov., a novel acid-tolerant representative of the order <Emphasis Type="Italic">Planctomycetales</Emphasis>

Two novel strains of budding bacteria, Z-0071^T and Z-0072, were isolated from dystrophic humified waters formed by xylotrophic fungi in the course of spruce wood degradation. The cells of both strains are coccoid (0.95–1.80 μm), nonmotile, single or arranged in pairs. The cells have a complex system of intracellular membranes and are covered with fimbriae and surrounded by a mucous capsule up to 0.3 μm thick. Both strains are aerobic organoheterotrophic, mesophilic, and acid-tolerant microorganisms that are able to grow under microaerobic conditions. They utilize N-acetyl-glucosamine, carbohydrates, and lactate as growth substrates. The strains grow in a pH range of 4.0–7.5 with an optimum at 6.0–6.5. The temperature range for growth is 4–30°C, with an optimum at 25–28°C. Strains Z-0071^T and Z-0072, inhabitants of dystrophic low-mineral waters, are NaCl-sensitive: the NaCl content in the media above 0.5 g/l inhibited growth. The main fatty acids of strains Z-0071^T and Z-0072 are C_16:0, C_18:1ω9c, and C_{18:2ω9c, 12c}. The DNA G + C base content is 51.2–51.7 mol %. The sequences of the 16S rRNA gene fragments (1310 bp) of strains Z-0071^T and Z-0072 were found to be identical. The obtained sequences showed a 94.3% similarity with the sequences of the type strain of the most closely related species Singulisphaera acidiphila MOB10≅T. The phenotypic and phylogenetic properties of strains Z-0071^T and Z-0072 support classification of these strains within the genus Singulisphaera as a new species Singulisphaera mucilagenosa sp. nov., with the type strain Z-0071^T (VKM B-2626).     

<Emphasis Type="Italic">Salinarchaeum laminariae</Emphasis> gen. nov., sp. nov.: a new member of the family <Emphasis Type="Italic">Halobacteriaceae</Emphasis> isolated from salted brown alga <Emphasis Type="Italic">Laminaria</Emphasis>

Halophilic archaeal strains R26^T and R22 were isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. Cells from the two strains were pleomorphic rods and Gram negative, and colonies were red pigmented. Strains R26^T and R22 were able to grow at 20–50°C (optimum 37°C) in 1.4–5.1 M NaCl (optimum 3.1–4.3 M) at pH 5.5–9.5 (optimum pH 8.0–8.5) and neither strain required Mg²⁺ for growth. Cells lyse in distilled water and the minimum NaCl concentration required to prevent cell lysis was 8% (w/v) for strain R26^T and 12% (w/v) for strain R22. The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and minor phosphatidylglycerol sulfate; glycolipids were not detected. Phylogenetic analyses based on 16S rRNA genes and rpoB′ genes revealed that strains R26^T and R22 formed a distinct clade with the closest relative, Natronoarchaeum mannanilyticum. The DNA G+C content of strains R26^T and R22 was 65.8 and 66.4 mol%, respectively. The DNA–DNA hybridization value between strains R26^T and R22 was 89%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the strains R26^T and R22 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarchaeum laminariae gen. nov., sp. nov. is proposed. The type strain is R26^T (type strain R26^T = CGMCC 1.10590^T = JCM 17267^T, reference strain R22 = CGMCC 1.10589).     

<Emphasis Type="Italic">Rhizobium sphaerophysae</Emphasis> sp. nov., a novel species isolated from root nodules of <Emphasis Type="Italic">Sphaerophysa salsula</Emphasis> in China

Four gram-negative, aerobic, motile, non-spore, forming rods with a wide pH and temperature range for growth (pH 7.0–11.0, optimum pH 8.0; 20–45°C, optimum 28°C) strains were isolated from root nodules of Sphaerophysa salsula and characterized by means of a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the four strains formed a new lineage related to the genus Rhizobium and the sequence similarities between the isolate and the most related type strain Rhizobium giardinii was 96.5%. These strains also formed a distinctive group from the reference strains for defined Rhizobium species based on housekeeping gene sequences (atpD and recA), BOX-PCR fingerprinting, phenotypic features and symbiotic properties. The representative strain CCNWGS0238^T has DNA-DNA relatedness of less than 33.4% with the most closely related species R. giardinii. It is therefore proposed as a new species, Rhizobium sphaerophysae sp. nov., with isolate CCNWGS0238^T (=ACCC17498^T = HAMBI3074^T) as the type strain.     

<Emphasis Type="Italic">Virgibacillus litoralis</Emphasis> sp. nov., a moderately halophilic bacterium isolated from saline soil

A Gram-positive, moderately halophilic, endospore-forming, catalase- and oxidase-positive, motile, rod-shaped, aerobic bacterium, designated strain JSM 089168^T, was isolated from saline soil collected from Naozhou Island, Leizhou Bay, South China Sea. The organism was able to grow with 2–25% (w/v) total salts (optimum, 5–10%), at pH 6.0–10.0 (optimum, pH 8.0) and 10–45°C (optimum, 30°C). meso-Diaminopimelic acid was present in the cell-wall peptidoglycan. The strain contained MK-7 as the predominant menaquinone, and diphosphatidylglycerol and phosphatidylglycerol as the major polar lipids. The major cellular fatty acids were anteiso-C_15:0, iso-C_15:0 and anteiso-C_17:0, and the DNA G + C content was 40.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain JSM 089168^T should be assigned to the genus Virgibacillus, being related most closely to the type strains of Virgibacillus carmonensis (sequence similarity 97.6%), Virgibacillus necropolis (97.3%) and Virgibacillus halodenitrificans (97.1%). Levels of DNA–DNA relatedness between strain JSM 089168^T and the type strains of V. carmonensis, V. necropolis and V. halodenitrificans were 20.4, 14.3 and 12.0%, respectively. The combination of phylogenetic analysis, DNA–DNA relatedness, phenotypic characteristics and chemotaxonomic data supported the view that strain JSM 089168^T represents a novel species of the genus Virgibacillus, for which the name Virgibacillus litoralis sp. nov. is proposed. The type strain is JSM 089168^T (=DSM 21085^T =KCTC 13228^T). The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain JSM 089168^T is FJ425909.     

<Emphasis Type="Italic">Ectothiorhodospira magna</Emphasis> sp. nov., a new large alkaliphilic purple sulfur bacterium

Two strains of purple sulfur bacteria of the family Ectothiorhodospiraceae were isolated from moderately saline steppe lakes (with pH above 9.0) of the Transbaikal region (strain B7-7) and Mongolia (strain M10). The cells of the novel strains were spiral-shaped, 2.0–3.2 × 9.6–20.0 μm, motile due to a polar tuft of flagella. Photosynthetic pigments were represented by bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Photosynthetic membranes were represented by long strands of lamellae distributed throughout the whole cell; unlike most Ectothiorhodospiraceae species, the membranes were not packed into regular stacks. Bacteria were capable of weak growth on sulfide and slow grow on hydrogen under photoautotrophic conditions. The best growth was noted on sulfide in the presence of acetate and bicarbonate. Thiosulfate did not stimulate phototrophic growth, even in the presence of organic substrates. The new isolates were alkaliphiles growing at a pH optimum of 9–10. Growth was possible within a salinity range of 0–80 g/l NaCl, with an optimum at 5–15 g/l NaCl. The morphology, the structure of the photosynthetic apparatus (strands of lamellae), and the physiology of the new strains were similar to those of Thiorhodospira sibirica. However, analysis of the 16S rRNA gene sequences demonstrated that the studied isolates were closely related to the type strain Ectothiorhodospira shaposhnikovii (99% similarity) of the family Ectothiorhodospiraceae, whereas the level of similarity between the new strains and Thiorhodospira sibirica was only 94–95%. According to the results of DNA-DNA hybridization, the DNA-DNA homology level between the tested strains was almost 100%; the similarity between the new isolates and the type strain Ectothiorhodospira shaposhnikovii was only 58%. The isolates differed from other representatives of the genus Ectothiorhodospira in the structure of the gene encoding the key enzyme of autotrophic CO₂ fixation, ribulose-1,5-bisphosphate carboxylase (RuBisCo), which was similar to the RuBisCo genes of members of another family of sulfur bacteria, Chromatiaceae. The new isolates of purple bacteria were described as a new species of the genus Ectothiorhodospira, Ect. magna sp. nov. with the type strain B7-7^T (= VKM B-2537 = DSM 22250).     

<Emphasis Type="Italic">Aphanomyces sinensis</Emphasis> sp. nov., isolated from juvenile soft-shelled turtle, <Emphasis Type="Italic">Pelodiscus sinensis</Emphasis>, in Japan

A species of Aphanomyces was isolated from juvenile soft-shelled turtles, Pelodiscus sinensis, cultured in Japan. Typically, an infected turtle showed small whitish maculae on the carapace. Many hyphae were observed in the epidermis. The hyphae were isolated using glucose–yeast (GY) agar plates. The morphological characteristics were very similar to those of Aphanomyces laevis, but a clear nuclear spot was observed in the center of the oospore in the strains isolated from the soft-shelled turtles. The optimal growth temperature for the isolates was 25–30°C and the optimum pH was 6–9. Experimental infection tests with isolates produced small whitish maculae on the carapace, and soft-shelled turtles artificially infected with the zoospores showed high mortality, especially in the high-dose group. Phylogenetic analysis based on the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) indicated that the isolates from the soft-shelled turtles were unidentified species of Aphanomyces. As a result, the strain was described as a new species, Aphanomyces sinensis.     

<Emphasis Type="Italic">Halobacillus naozhouensis</Emphasis> sp. nov., a moderately halophilic bacterium isolated from a sea anemone

A moderately halophilic, Gram-positive, catalase- and oxidase-positive, rod-shaped, aerobic bacterium, designated strain JSM 071068^T, was isolated from a sea anemone (Anthopleura xanthogrammica) collected from the Naozhou Island on the Leizhou Bay in the South China Sea. Cells were motile by means of peritrichous flagella and formed ellipsoidal endospores lying in subterminal swollen sporangia. Strain JSM 071068^T was able to grow with 1–20% (w/v) total salts (optimum, 6–9%), at pH values of 6.0–10.0 (optimum, pH 7.5) and a temperature range of 10–35°C (optimum, 25°C). meso-Diaminopimelic acid was present in the cell-wall peptidoglycan. The predominant menaquinone was MK-7 and the major cellular fatty acids were anteiso-C_15:0, anteiso-C_17:0 and iso-C_15:0. The genomic DNA G + C content was 42.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain JSM 071068^T belonged to the genus Halobacillus. The 16S rRNA gene sequence similarities between strain JSM 071068^T and the type strains of the recognized Halobacillus species ranged from 97.9% (with Halobacillus alkaliphilus) to 95.3% (with Halobacillus kuroshimensis). The levels of DNA–DNA relatedness between the new isolate and the type strains of H. alkaliphilus, Halobacillus campisalis, Halobacillus halophilus and Halobacillus seohaensis were 25.6, 22.1, 10.8 and 13.2%, respectively. The combination of phylogenetic analysis, DNA–DNA relatedness, phenotypic characteristics and chemotaxonomic data supported the view that strain JSM 071068^T represents a new species of the genus Halobacillus, for which the name Halobacillus naozhouensis sp. nov. is proposed, with JSM 071068^T (=DSM 21183^T =KCTC 13234^T) as the type strain. The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain JSM 071068^T is EU925615.     

<Emphasis Type="Italic">Halobacillus hunanensis</Emphasis> sp. nov., a moderately halophilic bacterium isolated from a subterranean brine

A moderately halophilic, Gram-positive, catalase- and oxidase-positive, rod-shaped, aerobic bacterium, designated strain JSM 071077^T, was isolated from a subterranean brine sample collected from a salt mine in Hunan Province, China. Cells were motile by means of peritrichous flagella and formed ellipsoidal endospores lying in subterminal swollen sporangia. Strain JSM 071077^T was able to grow with 2–25% (w/v) total salts (optimum, 5–10%), at pH 6.0–10.0 (optimum, pH 7.5) and 10–40°C (optimum, 25–30°C). meso-Diaminopimelic acid was present in the cell-wall peptidoglycan. The predominant menaquinone was MK-7, and the major cellular fatty acids were anteiso-C_15:0, anteiso-C_17:0 and iso-C_15:0. The genomic DNA G+C content was 41.8 mol%. Phylogenetic analyses based on 16S rRNA gene sequence comparisons revealed that strain JSM 071077^T should be assigned to the genus Halobacillus, being related most closely to the type strain of Halobacillus naozhouensis (98.8% sequence similarity), and the two strains formed a distinct subline in the neighbor-joining, minimum-evolution and maximum-parsimony phylogenetic trees. The sequence similarities between the novel isolate and the type strains of other recognized Halobacillus species ranged from 97.6% (with Halobacillus alkaliphilus) to 95.2% (with Halobacillus kuroshimensis). The results of the phylogenetic analyses, combined with DNA–DNA relatedness data, phenotypic characteristics and chemotaxonomic information, support that strain JSM 071077^T represents a new species of the genus Halobacillus, for which the name Halobacillus hunanensis sp. nov. is proposed. The type strain is JSM 071077^T (=DSM 21184^T = KCTC 13235^T).     

<Emphasis Type="Italic">Larkinella arboricola</Emphasis> sp. nov., a new spiral-shaped bacterium of the phylum <Emphasis Type="Italic">Bacteroidetes</Emphasis> isolated from the microbial community of decomposing wood

An aerobic gram-negative bacterial strain Z-0532 with ring-shaped cells forming spirals in the course of growth was isolated from the humified solution produced by spruce wood decomposition. The new isolate was a chemoorganotrophic, mesophilic, moderately acidophilic organism with the temperature range of 6–32°C (optimum at 25–28°C) and pH range from 4.7 to 7.2 (optimum at pH 5.5–6.5). A broad range of substrates was used as carbon and energy sources, including sugars, some organic acids and polyalcohols, and soluble polymeric compounds (gelatin, esculin, starch, xylan, laminarin, dextrin, casein hydrolysate, and Tween-40). According to its physiological and biochemical characteristics, strain Z-0532 is a typical member of the trophic group of oligotrophic bacteria, which utilize the products of wood hydrolysis dissipated by xylotrophic microorganisms. The G+C base content of strain Z-0532 was 52.1 mol %. Sequencing of the 16S rRNA gene of the new isolate revealed 98% similarity to Larkinella insperata LMG 22510^T, which is a recently described species of the family Spirosomaceae of the phylum Bacteroidetes. The level of DNA: DNA homology between this species and strain Z-0532 was only 40%. The differences in the phenotypic and genotypic characteristics suggested classification of the isolate obtained from decomposing wood as a new species of the genus Larkinella, Larkinella arboricola sp. nov., with the type strain Z-0532^T (=VKM B-2528^T = DSM 21851^T).     

Diagnostic properties of three conventional selective plating media for selection of <Emphasis Type="Italic">Bacillus cereus</Emphasis>, <Emphasis Type="Italic">B. thuringiensis</Emphasis> and <Emphasis Type="Italic">B. weihenstephanensis</Emphasis>

The aim of this study was to assess the diagnostic properties of the two selective plating media and a chromogenic medium for identification of Bacillus cereus. The 324 isolates were B. cereus (37%), Bacillus weihenstephanensis (45%) or Bacillus thuringiensis (18%), as identified by a new combination of techniques. All isolates were growing on mannitol–egg yolk–polymyxin agar (MYP), and they did not form acid from mannitol. However, a significant lower number of B. thuringiensis isolates did not show lecithinase activity. All isolates were also growing on polymyxin–egg yolk–mannitol–bromothymol blue agar (PEMBA); however, 11% isolates indicated that they did produce acid from mannitol, and 15% isolates did not show any lecithinase activity. Five of the isolates did not grow at all on the chromogenic agar, and 14 of the growing isolates were β-glucosidase negative. It is concluded that the two recommended selective plating media MYP and PEMBA for detection of B. cereus group bacteria both have their limitations for identification of some B. cereus, B. weihenstephanensis or B. thuringiensis. However, MYP is preferable compared to PEMBA. The chromogenic medium has its own advantages and limitations, and some of the limitations seem to be solved by incubation at 30°C instead of the recommended 37°C.     

Mercury Tolerance of Thermophilic <Emphasis Type="Italic">Bacillus</Emphasis> sp. and <Emphasis Type="Italic">Ureibacillus</Emphasis> sp

Although resistance of microorganisms to Hg(II) salts has been widely investigated and resistant strains have been reported from many eubacterial genera, there are few reports of mercuric ion resistance in extremophilic microorganisms. Moderately thermophilic mercury resistant bacteria were selected by growth at 62 °C on Luria agar containing HgCl₂. Sequence analysis of 16S rRNA genes of two isolates showed the closest matches to be with Bacillus pallidus and Ureibacillus thermosphaericus. Minimum inhibitory concentration (MIC) values for HgCl₂ were 80 μg/ml and 30 μg/ml for these isolates, respectively, compared to 10 μg/ml for B. pallidus H12 DSM3670, a mercury-sensitive control. The best-characterised mercury-resistant Bacillus strain, B. cereus RC607, had an MIC of 60 μg/ml. The new isolates had negligible mercuric reductase activity but removed Hg from the medium by the formation of a black precipitate, identified as HgS by X-ray powder diffraction analysis. No volatile H₂S was detected in the headspace of cultures in the absence or presence of Hg²⁺, and it is suggested that a new mechanism of Hg tolerance, based on the production of non-volatile thiol species, may have potential for decontamination of solutions containing Hg²⁺ without production of toxic volatile H₂S.     

<Emphasis Type="Italic">Haliphthoros milfordensis</Emphasis> isolated from black tiger prawn larvae (<Emphasis Type="Italic">Penaeus monodon</Emphasis>) in Vietnam

 A marine fungus was isolated from the black tiger prawn Penaeus monodon at Nha Trang, Vietnam, on March 20, 2001 and named isolate NJM 0131. The fungus was identified as Haliphthoros milfordensis from the characteristics of asexual reproduction, and its physiological characteristics were investigated. Although the optimum temperature for growth of the isolate was 25°–30°C, the fungus grew at a wide range of temperatures (15°–40°C). H. milfordensis grew well in 50%–100% seawater, but poorly in PYG agar containing 1.0%–5.0% NaCl and KCl. The fungus grew at a wide range of pH (4.0–11.0) with the optimum pH value of 7.0–9.0. The isolate also showed pathogenicity to swimming crab larvae (Portunus trituberculatus) by artificial infection, but mortality was not high. This is the first report of disease in the black tiger prawn P. monodon in Vietnam caused by H. milfordensis. Received: July 22, 2002 / Accepted: January 21, 2003 Correspondence to:K. Hatai     

<Emphasis Type="Italic">Hoeflea siderophila</Emphasis> sp. nov., a new neutrophilic iron-oxidizing bacterium

A new representative of neutrophilic iron-oxidizing bacteria was isolated from the iron-containing sediments of the brackish low-temperature iron-rich spring of the Staraya Russa Resort (Novgorod region, Russia). The cells of strain Hf1 were thin, slightly curved rods, motile by means of a single polar flagellum. The bacterium reproduced by binary division and was capable of producing rosettes. Optimal growth was observed within the pH range of 6.2–8.5 (with an optimum at 7.5), at 9–38°C (with an optimum at 30°C), and in the salinity range of 0.1–8.5% NaCl (with an optimum at 1%). The organism was a facultative anaerobe. The strain was capable of mixotrophic and organoheterotrophic growth. Fe(II) oxidation occurred under anaerobic conditions via reduction of NO₃⁻ and N₂O, or under microaerobic conditions with oxygen as an electron acceptor. According to phylogenetic analysis based on the comparison of the 16S rRNA gene sequences, the strain was closest to the organotrophic marine bacterium Hoeflea phototrophica (98.5% similarity). The level of DNA-DNA homology with the type species of the genus Hoeflea was 19%. The DNA G + C base content was 57.5 mol %. According to its phenotypic and chemotaxonomic properties, as well as to the results of phylogenetic analysis, strain Hf1 was classified into the genus Hoeflea of the family Phyllobacteriaceae, order Rhizobiales of the phylum Alphaproteobacteria as a novel species, Hoeflea siderophila sp. nov. The type strain is Hf1^T (=DSM 21587 = VKM A7094). The GenBank accession number for the 16S rRNA gene sequences of strain Hf1^T is EU670237.     

<Emphasis Type="Italic">Pseudonocardia serianimatus</Emphasis> sp. nov., a novel actinomycete isolated from the surface-sterilized leaves of <Emphasis Type="Italic">Artemisia annua</Emphasis> L.

An aerobic, non-motile, catalase-positive, Gram-stain positive actinomycete designated YIM 63233^T was isolated from the surface-sterilized leaves of Artemisia annua L. and characterized using a polyphasic taxonomic approach. Optimal growth occurred at 20–28°C, pH 6.0–7.0 and in the presence of 0–3% (w/v) NaCl. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 63233^T clustered with species of the genus Pseudonocardia, displaying ≥1.2% sequence divergence with recognized species of this genus (from 98.8 to 94.0%). Relatively low levels of DNA–DNA relatedness were found between strain YIM 63233^T and Pseudonocardia petroleophila IMSNU 22072^T, which supported the classification of strain YIM 63233^T within a novel species of the genus Pseudonocardia. The G + C content of genomic DNA was 72.0 mol%. Strain YIM 63233^T possessed chemotaxonomic markers that were consistent with classification in the genus Pseudonocardia, i.e. the predominant fatty acids were iso-C16:0 (32.27%), C16:0 10-methyl (8.73%) and C17:1ω8c (8.30%), whilst the predominant menaquinone was MK-8(H₄). The diagnostic diamino acid of the cell-wall peptidoglycan was meso-diaminopimelic acid. The major cell wall sugars were glucose, arabinose, galactose, mannose and rhamnose. The results of physiological and biochemical tests and DNA–DNA hybridization allowed the phenotypic and genotypic differentiation of strain YIM 63233^T from its closest phylogenetic neighbours. Therefore, the new isolate YIM 63233^T represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia serianimatus sp. nov. is proposed. The type strain is YIM 63233^T (=DSM 45302^T = CCTCC AA 208079^T).     

<Emphasis Type="Italic">Psychroflexus lacisalsi</Emphasis> sp. nov., a moderate halophilic bacterium isolated from a hypersaline lake (Hunazoko-Ike) in Antarctica

A novel Gram-negative, aerobic, moderate halophilic, and psychrotolerant bacterium, designated as strain H7^T, was isolated from a hypersaline lake located in Skarvsnes, Antarctica. Cells were filaments with varying lengths. Coccoid bodies developed in old cultures. Growth occurred with 0.5–15% (w/v) NaCl (optimum, 5.8–7.0%), at pH 6.0–10.0 (optimum, pH 7.0–8.0), and at 10–28°C (optimum, 25°C). The strain had a G+C content of 34.9 mol%, which is within the range of 32–36 mol% reported for the genus Psychroflexus. Chemotaxonomic data (major respiratory quinone: MK-6; major fatty acids: aC_15:0, iC_16:0 3-OH, and aC_{15: 1} A) supported the classification of strain H7^T within the genus Psychroflexus. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain H7^T should be assigned to the genus Psychroflexus and has a homology with Psychroflexus salinarum (98.2%), P. sediminis (96.1%), P. torquis (95.2%), P. tropicus (95.8%), and P. gondwanense (92.2%). Strain H7 is not identified as P. salinarum because that DNA-DNA hybridization data were 8.5% between strain H7^T and P. salinarum. The combination of phylogenetic analysis, DNA-DNA hybridization data, phenotypic characteristics, and chemotaxonomic differences supported the view that strain H7^T represents a novel species of the genus Psychroflexus. The name Psychroflexus lacisalsi is proposed, and the type strain is H7^T (=JCM 16231^T =KACC 14089^T).     

<Emphasis Type="Italic">Joostella atrarenae</Emphasis> sp. nov., a novel member of the <Emphasis Type="Italic">Flavobacteriaceae</Emphasis> originating from the black sea sand of Jeju Island

Strain M1-2^T was isolated from the black sand from the seashore of Jeju Island, Republic of Korea and was classified using a polyphasic taxonomic approach. Strain M1-2^T appeared as Gram-negative, motile rods that could grow in the presence of 1–10% (w/v) NaCl and at temperatures ranging from 4 to 37°C. This isolate has catalase and oxidase activity and hydrolyses aesculin, DNA and l-tyrosine. Based on phylogenetic analysis using 16S rRNA gene sequences, strain M1-2^T belongs to the genus Joostella and is clearly distinct from the other described species of this genus, Joostella marina (type strain En5^T). The 16S rRNA gene sequence similarity level between M1-2^T and J. marina En5^T is 97.2%, and the DNA–DNA relatedness value between the two strains is 23.9%. Strain M1-2^T contains MK-6 as the major menaquinone and iso-C_15:0, summed feature 3 (C_16:1 ω7c and/or iso-C_15:0 2OH) and iso-C_17:0 3OH as major cellular fatty acids. The DNA G + C content is 32.3 mol%. These data suggest that strain M1-2^T should be classified as a novel species, for which the name Joostella atrarenae sp. nov. is proposed. The type strain for the novel species is M1-2^T (= KCTC 23194^T = NCAIM B.002413^T).     

Novel ultramicrobacteria,strains NF4 and NF5, of the genus <Emphasis Type="Italic">Chryseobacterium</Emphasis>: Facultative epibionts of <Emphasis Type="Italic">Bacillus subtilis</Emphasis>

Two strains, NF4 and NF5, of a yellow-colored gram-negative bacterium were isolated from sediments of Lake Baikal and from old oil sludge of the Nizhnekamsk oil-processing plant. The cells of the strains are ultrasmall coccoids or short rods, measuring 0.2–0.4 × 0.2–0.5 μm; the average cell volume ranges from 0.004 to 0.04 μm³. A considerable proportion (30–60%) of cells have nanometer dimensions (180–300 nm in diameter and 0.004–0.02 μm³ in volume). The new isolates are thus among the smallest representatives of presently known free-living ultramicrobacteria. The two studied isolates are gram-negative nonmotile cells possessing a pronounced outer membrane. The cells do not have flagella and are not capable of gliding motility. They divide by constriction, budding, and multiple septation. The multiplicity of reproduction mechanisms results in a high degree of cell polymorphism. The isolates are chemoorganotrophic, aerobic, psychrotolerant, oxidase- and catalase-positive. Their characteristic trait is the absence of extracellular hydrolytic enzymes, such as proteases, lipases, pectinases, and cellulases. Menaquinone MK-6 is the main respiratory quinone; the flexirubin pigment was not detected. The G + C contents of the DNA of strains NF4 and NF5 are 40.8 and 40.5 mol %, respectively. The DNA-DNA hybridization level of strains NF4 and NF5 was close to 100%. Analysis of the 16S rRNA gene sequences and the fatty acid compositions showed that the isolates are most closely related to certain representatives of the genus Chryseobacterium (C. solincola, C. antarcticum, and C. jeonii). However, the differences in the 16S rRNA gene sequences, as well as in the phenotypic properties, such as formation of ultrasmall cells, the absence of extracellular hydrolases, oligotrophy, and the capacity for epibiosis on bacterial cells, suggest that the studied strains belong to a new species of the genus Chryseobacterium. The capacity for epibiosis, i.e., the ability to exist in a tightly adhered state on the surfaces of host Bacillus subtilis cells, is a peculiar trait of the studied isolates. It is assumed that adhesion of the cells of strains NF4 and NF5 (members of the phylum Bacteroidetes) occurs via by the same unique mechanism as the mechanism that we previously described for representatives of Alphaproteobacteria (Kaistia sp., NF1, and NF3), which use polysaccharide chains equipped with sticky granules as trapping and constricting cords.     

<Emphasis Type="Italic">Ancylobacter abiegnus</Emphasis> sp. nov., an oligotrophic member of the xylotrophic mycobacterial community

A new species of the genus Ancylobacter, exemplified by strain Z-0056, was isolated from dystrophic humified waters formed by xylotrophic fungi grown on decaying spruce wood. The cells of strain Z-0056 (0.65–0.9 μm) are coccoid, gram-negative, with fimbriae, and nonmotile. The strain is pleomorphic and reproduces by nonuniform division. Strain Z-0056 is an aerobic organoheterotroph and a mesophilic and moderately acidophilic oligotrophic microorganism. As an inhabitant of dystrophic ultrafresh waters, strain Z-0056 is sensitive to NaCl. The bacterium utilizes organic acids (acetate, pyruvate, oxalate, gluconate, malate, succinate, and citrate), as well as xylose and xylan. The microorganism grows in a pH range of 4.0–8.0, with an optimum at pH 5.5. The temperature range for growth is 15–25°C, with an optimum at 20°C. According to its ecophysiological properties, strain Z-0056 belongs to the group of ombrophilic dissipotrophs. The DNA G+C base content is 66.8 mol %. According to phylogenetic analysis, strain Z-0056 belongs to the genus Ancylobacter. Strain Z-0056 showed the highest similarity (98.3%) with the type strain of the species A. oerskovii. The phenotypic and phylogenetic properties of strain Z-0056 support classification of this microorganism within the genus Ancylobacter as the novel species Ancylobacter abiegnus sp. nov.     

<Emphasis Type="Italic">Deinococcus soli</Emphasis> sp. nov., a gamma- and UV-radiation-resistant bacterium from north-west China

An ionizing- and UV-radiation-resistant bacterial strain, designated ZLM-202^T, was isolated from an arid soil sample collected from Xinjiang Province, north-west China. The soil sample was irradiated before serial dilution plating was performed using twofold-diluted marine agar. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZLM-202^T was a member of the genus Deinococcus, exhibiting sequence similarities of 86.3–92.2% to the type strains of recognized Deinococcus species. Strain-ZLM-202^T was strictly aerobic and showed optimum growth at 30–37°C and pH 7.0. The major respiratory menaquinone was MK-8. The major fatty acids were 16:1 ω7c, 16: 0, 15: 1 ω6c, 15: 0 iso and 16: 1 ω5c. L-ornithine was detected in its peptidoglycan. The polar lipid profile consisted mainly of various unknown phosphoglycolipids, aminophospholipids, glycolipids and phospholipids. The DNA G + C content was 65.5 mol. %. The strain was shown to be extremely resistant to gamma radiation (>10 kGy) and UV light (>600 J m⁻²). On the basis of the phylogenetic, chemotaxonomic and phenotypic data, strain ZLM-202^T represents a novel species of the genus Deinococcus, for which the name Deinococcus soli sp. nov. is proposed. The type strain is ZLM-202^T (=CCTCC AB 208223^T=KCTC 13419^T).