Venatorbacter cucullus gen. nov sp. nov a novel bacterial predator.

A novel Gram-stain negative, aerobic, halotolerant, motile, rod-shaped, predatory bacterium ASxL5T, was isolated from a bovine slurry tank in Nottinghamshire, UK using Campylobacter hyointestinalis as prey. Other Campylobacter species and members of the Enterobacteriaceae were subsequently found to serve as prey. Weak axenic growth on Brain Heart Infusion agar was achieved upon subculture without host cells. The optimal growth conditions were 37 °C, at pH 7. Transmission electron microscopy revealed some highly unusual morphological characteristics related to prey availability. Phylogenetic analyses using 16S rRNA gene sequences showed that the isolate was related to members of the Oceanospirillaceae family but could not be classified clearly as a member of any known genus. Whole genome sequencing of ASxL5T confirmed the relationship to members the Oceanospirillaceae. Database searches revealed that several ASxL5T share 16S rRNA gene sequences with several uncultured bacteria from marine, and terrestrial surface and subsurface water. We propose that strain ASxL5T represents a novel species in a new genus. We propose the name Venatorbacter cucullus gen. nov., sp. nov. with ASxL5T as the type strain.

Maribrevibacterium harenarium gen. nov., sp. nov., represented by a marine strain of the family Oceanospirillaceae.

A Gram-stain-negative, non-motile, facultatively anaerobic, short rod-shaped bacterium, designated HB171799T, was isolated from seacoast sandy soil collected at Qishui Bay, Hainan, PR China. The chemotaxonomic analysis revealed that the respiratory quinones were Q-8 and Q-7, and the major cellular fatty acids were summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c), C16 : 0 and C18 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and an unidentified lipid. The size of the draft genome was 3.68 Mb with a DNA G+C content of 48.0 mol%. Results of phylogenetic analyses based on 16S rRNA gene and genome sequences showed that the novel isolate belonged to the family Oceanospirillaceae and formed a distinct subcluster at the base of the radiation of the genus Marinomonas. The highest sequence similarity (96.0 %) of the novel isolate was found to the type strains of Marinomonas fungiae JCM 18476T and Marinomonas ostreistagni DSM23425T. The whole genome-based phylogeny and differences in cellular fatty acids and polar lipids readily distinguished strain HB171799T from all the closely related validly published type strains. Strain HB171799T is therefore suggested to represent a novel species of a new genus in the family Oceanospirillaceae, for which the name Maribrevibacterium harenarium gen. nov., sp. nov. is proposed. The type strain is HB171799T (=CGMCC 1.16727T=JCM 33332T).

Complete genome sequence of Neptunomonas concharum JCM17730T: An acetate assimilating bacterium isolated from a dead ark clam.

The marine bacterium Neptunomonas concharum was firstly characterized in 2012. It preferred to utilize acetate as the carbon source to accumulate poly-3-hydroxybutyrate (PHB) as intracellular carbon and energy storage. Here we report the genomic characteristics of N. concharum JCM17730T. The complete genome sequence of N. concharum JCM17730T consists of 3,561,992 bp in one contig, without plasmid. Analysis of coding sequences revealed the presence of genomic features involved in acetate assimilation and PHB metabolism. The genome of N. concharum JCM17730T contains three genes encoding acetyl-CoA synthetase and two genes encoding isocitrate lyase. Three polyhydroxyalkanoate synthases and one polyhydroxyalkanoate depolymerase are scattered throughout the genomic DNA. The genome features provide interesting insights into the acetate and PHB metabolism of N. concharum JCM17730T and would facilitate further research on the genetic engineering of marine bacteria for efficient PHB production.

Characterization of polyhydroxyalkanoate synthases from the marine bacterium Neptunomonas concharum JCM17730.

Neptunomonas concharum JCM17730 was isolated from an ark clam sample and characterized as a mesophilic bacterium. The genome of N. concharum JCM17730 contains thirteen genes related to polyhydroxyalkanoates (PHA) metabolism. Three PHA synthase encoding genes were identified, and phylogenetic analysis of enzyme sequences suggested the presence of two class I PHA synthases and one class III PHA synthase. The PHA synthases of N. concharum were heterologously expressed with acetyl-CoA acetyltransferase and acetoacetyl-CoA reductase in Escherichia coli to confirm the catalytic activity of each PHA synthase. Recombinants harboring different PHA synthase exhibit important distinctions in poly-3-hydroxybutyrate synthesis ability under various temperatures. Decreased cultivation temperature (≤30 °C) significantly improved PHB titer and content. This is the first report on characterization of PHA synthases from the marine genus Neptunomonas and would provide molecular basis for PHA production using Neptunomonas species.

Regulatory relationship between quality variation and environment of Cistanche deserticola in three ecotypes based on soil microbiome analysis.

The environment affects the composition and function of soil microbiome, which indirectly influences the quality of plants. In this study, 16S amplicon sequencing was used to reveal the differences in soil microbial community composition of Cistanche deserticola in three ecotypes (saline-alkali land, grassland and sandy land). Through the correlation analysis of microbial community abundance, phenylethanoid glycoside contents and ecological factors, the regulatory relationship between microbial community and the quality variation of C. deserticola was expounded. The metabolic function profile of soil microbiome was predicted using Tax4Fun. Data showed that the soil microbial communities of the three ecotypes were significantly different (AMOVA, P < 0.001), and the alpha diversity of grassland soil microbial community was the highest. Core microbiome analysis demonstrated that the soil microbial communities of C. deserticola were mostly have drought, salt tolerance, alkali resistance and stress resistance, such as Micrococcales and Bacillales. The biomarkers, namely, Oceanospirillales (saline-alkali land), Sphingomonadales (grassland) and Propionibacteriales (sandy land), which can distinguish three ecotype microbial communities, were excavated through LEfSe and random forest. Correlation analysis results demonstrated that 2'-acetylacteoside is positively correlated with Oceanospirillales in saline-alkali land soil. The metabolic function profiles displayed highly enriched metabolism (carbohydrate and amino acid metabolisms) and environmental information processing (membrane transport and signal transduction) pathways. Overall, the composition and function of soil microbiomes were found to be important factors to the quality variation of C. deserticola in different ecotypes. This work provided new insight into the regulatory relationship amongst the environment, soil microbial community and plant quality variation.

Protein expression in the obligate hydrocarbon-degrading psychrophile Oleispira antarctica RB-8 during alkane degradation and cold tolerance.

In cold marine environments, the obligate hydrocarbon-degrading psychrophile Oleispira antarctica RB-8, which utilizes aliphatic alkanes almost exclusively as substrates, dominates microbial communities following oil spills. In this study, LC-MS/MS shotgun proteomics was used to identify changes in the proteome induced during growth on n-alkanes and in cold temperatures. Specifically, proteins with significantly higher relative abundance during growth on tetradecane (n-C14 ) at 16°C and 4°C have been quantified. During growth on n-C14 , O. antarctica expressed a complete pathway for the terminal oxidation of n-alkanes including two alkane monooxygenases, two alcohol dehydrogenases, two aldehyde dehydrogenases, a fatty-acid-CoA ligase, a fatty acid desaturase and associated oxidoreductases. Increased biosynthesis of these proteins ranged from 3- to 21-fold compared with growth on a non-hydrocarbon control. This study also highlights mechanisms O. antarctica may utilize to provide it with ecological competitiveness at low temperatures. This was evidenced by an increase in spectral counts for proteins involved in flagella structure/output to overcome higher viscosity, flagella rotation to accumulate cells and proline metabolism to counteract oxidative stress, during growth at 4°C compared with 16°C. Such species-specific understanding of the physiology during hydrocarbon degradation can be important for parameterizing models that predict the fate of marine oil spills.

Analysis of allosteric communication in a multienzyme complex by ancestral sequence reconstruction.

Tryptophan synthase (TS) is a heterotetrameric αßßα complex. It is characterized by the channeling of the reaction intermediate indole and the mutual activation of the α-subunit TrpA and the ß-subunit TrpB via a complex allosteric network. We have analyzed this allosteric network by means of ancestral sequence reconstruction (ASR), which is an in silico method to resurrect extinct ancestors of modern proteins. Previously, the sequences of TrpA and TrpB from the last bacterial common ancestor (LBCA) have been computed by means of ASR and characterized. LBCA-TS is similar to modern TS by forming a αßßα complex with indole channeling taking place. However, LBCA-TrpA allosterically decreases the activity of LBCA-TrpB, whereas, for example, the modern ncTrpA from Neptuniibacter caesariensis allosterically increases the activity of ncTrpB. To identify amino acid residues that are responsible for this inversion of the allosteric effect, all 6 evolutionary TrpA and TrpB intermediates that stepwise link LBCA-TS with ncTS were characterized. Remarkably, the switching from TrpB inhibition to TrpB activation by TrpA occurred between 2 successive TS intermediates. Sequence comparison of these 2 intermediates and iterative rounds of site-directed mutagenesis allowed us to identify 4 of 413 residues from TrpB that are crucial for its allosteric activation by TrpA. The effect of our mutational studies was rationalized by a community analysis based on molecular dynamics simulations. Our findings demonstrate that ancestral sequence reconstruction can efficiently identify residues contributing to allosteric signal propagation in multienzyme complexes.

Neptunomonas marina sp. nov., isolated from seawater.

Strain HPM-16T, isolated from seawater, was characterized using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of an up-to-date bacterial core gene set (92 protein clusters) indicated that strain HPM-16T formed a phylogenetic lineage in the genus Neptunomonas. Strain HPM-16T was most closely related to Neptunomonas concharum LHW37T with 16S rRNA gene sequence similarity of 96.7%. Cells were Gram-stain negative, facultatively anaerobic, motile by means of a single polar flagellum, rod-shaped and formed white colonies. Optimal growth occurred at 30-35 °C, pH 6.5-8, and in the presence of 2-5% NaCl. C18:1ω7c and summed feature 3 (C16:1ω7c and/or C16:1ω6c) were the predominant fatty acids. The only isoprenoid quinone was Q-8. The polar lipid profile revealed the presence of phosphatidylethanolamine, phosphatidylglycerol and several uncharacterized lipids. The major polyamines were putrescine and spermidine. The draft genome was approximately 3.68 Mb in size with a G + C content of 50.5 mol%. Differential phenotypic properties, together with the phylogenetic inference, demonstrate that strain HPM-16T should be classified as a novel species of the genus Neptunomonas, for which the name Neptunomonas marina sp. nov. is presented. The type strain is HPM-16T (= BCRC 80980T = LMG 29560T = KCTC 52235T).

Metagenomic and metatranscriptomic responses of natural oil degrading bacteria in the presence of dispersants.

Oil biodegradation has been extensively studied in the wake of the deepwater horizon spill, but the application of dispersant to oil spills in marine environments remains controversial. Here, we report metagenomic (MG) and metatranscriptomic (MT) data mining from microcosm experiments investigating the oil degrading potential of Canadian west and east coasts to estimate the gene abundance and activity of oil degrading bacteria in the presence of dispersant. We found that the addition of dispersant to crude oil mainly favours the abundance of Thalassolituus in the summer and Oleispira in the winter, two key natural oil degrading bacteria. We found a high abundance of genes related not only to n-alkane and aromatics degradation but also associated with transporters, two-component systems, bacterial motility, secretion systems and bacterial chemotaxis.

Implementing Morpholino-Based Nucleic Acid Sensing on a Portable Surface Plasmon Resonance Instrument for Future Application in Environmental Monitoring.

A portable surface plasmon resonance (SPR) instrument was tested for the first time for the detection of oligonucleotide sequences derived from the 16S rRNA gene of Oleispira antarctica RB-8, a bioindicator species of marine oil contamination, using morpholino-functionalized sensor surfaces. We evaluated the stability and specificity of morpholino coated sensor surfaces and tested two signal amplification regimes: (1) sequential injection of sample followed by magnetic bead amplifier and (2) a single injection of magnetic bead captured oligo. We found that the sensor surfaces could be regenerated for at least 85 consecutive sample injections without significant loss of signal intensity. Regarding specificity, the assay clearly differentiated analytes with only one or two mismatches. Signal intensities of mismatch oligos were lower than the exact match target at identical concentrations down to 200 nM, in standard phosphate buffered saline with 0.1 % Tween-20 added. Signal amplification was achieved with both strategies; however, significantly higher response was observed with the sequential approach (up to 16-fold), where first the binding of biotin-probe-labeled target oligo took place on the sensor surface, followed by the binding of the streptavidin magnetic beads onto the immobilized targets. Our experiments so far indicate that a simple coating procedure in combination with a relatively cost-efficient magnetic-bead-based signal amplification will provide robust SPR based nucleic acid sensing down to 0.5 nM of a 45-nucleotide long oligo target (7.2 ng/mL).

Isolation and characterization of a novel 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing plant growth promoting marine Gammaproteobacteria from crops grown in brackish environments. Proposal for Pokkaliibacter plantistimulans gen. nov., sp. nov., Balneatrichaceae fam. nov. in the order Oceanospirillales and an emended description of the genus Balneatrix.

Three novel strains namely, L1E11T, L1E4 and 228 were isolated as part of an ongoing study on 1-aminocyclopropane-1-carboxylate (ACC) deaminase expressing rhizobacteria from crops cultivated in saline affected coastal agro-ecosystems of Kerala, India. The novel strains were positive for many properties that are beneficial to plant growth including ACC deaminase (ACCd) activity that ranged from 1.87±0.27 to 2.88±0.71µmol of α-ketobutyrate/hr/mg of total protein. Presence of other traits such as biofilm formation, siderophore production, phosphate solubilisation, utilisation of root derived compounds and ability to colonise host roots indicates its plant-associated life style. In complement, the genomic data reveals gene features for higher adaptation to plant-associated environments. In-planta assays showed that L1E11T can promote and protect pokkali rice plants from 200mM NaCl stress. Phylogenetic, chemotaxonomic, phenotypic and genomic characterisation indicates that the novel strains belong to a novel genus and species of the order Oceanospirillales for which the names Pokkaliibacter gen. nov., and Pokkaliibacter plantistimulans sp. nov., are proposed with L1E11T (=DSM 28732T=MCC 2992T) as the type strain. Further, on the basis of low 16S rRNA sequence similarity, phylogenetic divergence, source of isolation and few differences in the phenotypic properties against its nearest taxon, a new family Balneatrichaceae fam. nov., is proposed to accommodate the two genera Balneatrix and Pokkaliibacter gen.nov. with Balneatrix as the type genus. An emended description of the genus Balneatrix is also presented.

Motiliproteus coralliicola sp. nov., a bacterium isolated from coral.

A Gram-stain-negative, non-spore-forming, aerobic, motile, ovoid or rod-shaped bacterium, designated strain C34T, was isolated from a Porites species coral on Weizhou Island, China. Optimal growth occurred in 4 % NaCl (w/v), at 30 °C and pH 8. The only detected respiratory quinone was Q-8. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two unidentified ninhydrin-positive lipids, one ninhydrin-positive unidentified phospholipid and two unidentified polar lipids. The genome DNA G+C content was 56.7 mol%. The major cellular fatty acids were C16 : 1ω7c/iso-C15 : 0 2-OH, C16 : 0, C18 : 1ω7c/ω6c, C18 : 0 and iso-C11 : 0 3-OH. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain C34T forms a stable cluster with Motiliproteus sediminis CICC 10858T (with the highest sequence similarity of 95.7 %). Strain C34T was also physiologically and chemical taxonomically similar to M. sediminis CICC 10858T, although they could be distinguished by colony colour on 2216E agar, the flagellum position and the diphosphatidylglycerol content in the cellular polar lipid. Thus, strain C34T is suggested to represent a new species in the genus Motiliproteus, for which the name Motiliproteus coralliicola is proposed. The type strain is C34T (=MCCC 1K03462T=KCTC 62319T).

Characterization of two styrene monooxygenases from marine microbes.

Styrene monooxygenases (SMOs) are highly stereoselective enzymes that catalyze the formation of chiral epoxides as versatile building blocks. To expand the enzyme toolbox, two bacterial SMOs were identified from the genome of marine microbes Paraglaciecola agarilytica NO2 and Marinobacterium litorale DSM 23545, and heterologously expressed in Escherichia coli in soluble form. Both of the resulting whole-cell biocatalysts exhibited maximal activity at 30 °C and pH 8.0. They catalyzed the sulfoxidation reactions, and the epoxidation of both conjugated and unconjugated styrene derivatives with up to >99%ee. MlSMO displayed higher activity toward most substrates tested. Compared to an established SMO from Pseudomonas species (PsSMO), MlSMO achieved 3.0-, 3.4- and 2.6-fold conversions for substrates styrene, cinnamyl alcohol and 4-vinyl-2, 3-dihydrobenzofuran, respectively.

Thermal regime and host clade, rather than geography, drive Symbiodinium and bacterial assemblages in the scleractinian coral Pocillopora damicornis sensu lato.

BACKGROUND: Although the term holobiont has been popularized in corals with the advent of the hologenome theory of evolution, the underlying concepts are still a matter of debate. Indeed, the relative contribution of host and environment and especially thermal regime in shaping the microbial communities should be examined carefully to evaluate the potential role of symbionts for holobiont adaptation in the context of global changes. We used the sessile, long-lived, symbiotic and environmentally sensitive reef-building coral Pocillopora damicornis to address these issues. RESULTS: We sampled Pocillopora damicornis colonies corresponding to two different mitochondrial lineages in different geographic areas displaying different thermal regimes: Djibouti, French Polynesia, New Caledonia, and Taiwan. The community composition of bacteria and the algal endosymbiont Symbiodinium were characterized using high-throughput sequencing of 16S rRNA gene and internal transcribed spacer, ITS2, respectively. Bacterial microbiota was very diverse with high prevalence of Endozoicomonas, Arcobacter, and Acinetobacter in all samples. While Symbiodinium sub-clade C1 was dominant in Taiwan and New Caledonia, D1 was dominant in Djibouti and French Polynesia. Moreover, we also identified a high background diversity (i.e., with proportions < 1%) of A1, C3, C15, and G Symbiodinum sub-clades. Using redundancy analyses, we found that the effect of geography was very low for both communities and that host genotypes and temperatures differently influenced Symbiodinium and bacterial microbiota. Indeed, while the constraint of host haplotype was higher than temperatures on bacterial composition, we showed for the first time a strong relationship between the composition of Symbiodinium communities and minimal sea surface temperatures. CONCLUSION: Because Symbiodinium assemblages are more constrained by the thermal regime than bacterial communities, we propose that their contribution to adaptive capacities of the holobiont to temperature changes might be higher than the influence of bacterial microbiota. Moreover, the link between Symbiodinium community composition and minimal temperatures suggests low relative fitness of clade D at lower temperatures. This observation is particularly relevant in the context of climate change, since corals will face increasing temperatures as well as much frequent abnormal cold episodes in some areas of the world.

Marinobacterium aestuarii sp. nov., a benzene-degrading marine bacterium isolated from estuary sediment.

A Gram-stain-negative, aerobic, motile, flagellated rod-shaped bacterium, designated ST58-10T, was isolated from an estuarine sediment in the Republic of Korea. The strain was able to degrade benzene. Growth of strain ST58-10T was observed at 4-35 °C (optimum, 20-25 °C), pH 5-9 (optimum, pH 7-8) and 1-8 % NaCl (optimum, 3 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain ST58-10T formed a phyletic lineage within the genus Marinobacterium of the family Oceanospirillaceae. Strain ST58-10T was most closely related to Marinobacterium profundum PAMC 27536T (99.6 %) and Marinobacterium rhizophilum CL-YJ9T (98.3 %), and to other members of the genus Marinobacterium(94.5-91.5 %). However, the mean value estimated by using the Genome-to-Genome Distance Calculator was 50.6±7.4 % with M. profundum PAMC 27536T and 30.9±2.8 with M. rhizophilum CL-YJ9T, respectively. An average nucleotide identity value was 89.0 % with M. profundum PAMC 27536T and 85.6 % with M. rhizophilum CL-YJ9T, respectively. The major fatty acids of strain ST58-10T were summed feature 3 (comprising C16 : 1ω7c/C16 : 1ω6c), summed feature 8 (comprising C18 : 1 ω7c/C18 : 1ω6c), C16 : 0 and C10 : 0 3-OH, and contained ubiquinone (Q-8) as the sole isoprenoid quinone. Phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminolipids, an unidentified glycolipid and an unidentified lipid were detected as polar lipids. The DNA G+C content of strain ST58-10T was 58.78 mol%. On the basis of the phenotypic, chemotaxonomic and molecular properties, strain ST58-10T represents a novel species of the genus Marinobacterium, for which the name Marinobacterium aestuarii sp. nov. is proposed. The type strain is ST58-10T (=KCTC 52193T=NBRC 112103T).

Production of indoleacetic acid by strains of the epiphytic bacteria Neptunomonas spp. isolated from the red alga Pyropia yezoensis and the seagrass Zostera marina.

Neptunomonas sp. BPy-1 is an epiphytic bacterium isolated from in vitro culture of the red alga Pyropia yezoensis. It uses ethanol as a sole carbon source and promotes the growth of host alga. A related bacterium, Neptunomonas sp. BZm-1, was isolated from leaves of Zostera marina found in the Yatsushiro Sea (Japan). BZm-1 showed 99% 16S rRNA sequence identity with Neptunomonas sp. BPy-1. Similar to BPy-1, BZm-1 grew in artificial seawater (ASW) medium containing ethanol or butanol. When thalli were treated with a multi-enzyme cleaner, the growth of treated thalli was retarded, but the addition of BZm-1 to the medium promoted growth. To explore the benefits of epiphytic bacteria, indoleacetic acid (IAA) production by isolated bacteria was examined under conditions of limited nutrients. Salkowski assays and GC-MS analysis revealed that both BZm-1 and BPy-1 excreted IAA during growth in ASW medium containing glucose or ethanol in the presence of tryptophan. In ASW medium containing tryptophan but lacking a carbon source, neither isolate grow, but produced IAA. ASW medium includes nitrate as the sole nitrogen source. In the absence of carbon source, different nitrogen forms in the presence of tryptophan did not affect IAA production by the two isolates. These findings indicate that IAA production by the two isolates is strictly dependent on tryptophan but less affected by carbon and nitrogen sources. Based on the different origins of BPy-1 and BZm-1, this mode of IAA production seems to be conserved among relatives of BPy-1.

Litoribrevibacter euphylliae sp. nov., isolated from the torch coral Euphyllia glabrescens.

Strain Eup a-2T, isolated from the torch coral Euphyllia glabrescens, was characterized using a polyphasic taxonomy approach. Cells of strain Eup a-2T were Gram-negative, aerobic and motile by three polar flagella and formed translucent colonies. Optimal growth occurred at 25 °C, pH 6-8 and in the presence of 2-4 % NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain Eup a-2T belonged to the genus Litoribrevibacter and showed the highest levels of sequence similarity with respect to Litoribrevibacter albus Y32T (97.8 %). Strain Eup a-2T contained summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0 as the predominant fatty acids. The predominant isoprenoid quinone was Q-8. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphophatidylglycerol. Genomic DNA G+C content of strain Eup a-2T was 49.1 mol%. The DNA-DNA hybridization value for strain Eup a-2T with L. albus Y32T was less than 30 %. Differential phenotypic properties, together with the phylogenetic inference, demonstrate that strain Eup a-2T should be classified as a novel species of the genus Litoribrevibacter, for which the name Litoribrevibactereuphylliae sp. nov. is presented. The type strain is Eup a-2T (=BCRC 81004T=LMG 29725T=KCTC 52438T).

Nitrincola alkalilacustris sp. nov. and Nitrincola schmidtii sp. nov., alkaliphilic bacteria isolated from soda pans, and emended description of the genus Nitrincola.

Three alkaliphilic and halotolerant bacterial strains, designated ZV-19T, R4-8T and S4-12, were isolated from the water of soda pans located in the Kiskunság National Park, Hungary. Cells of all three strains were Gram-staining-negative, rod-shaped, motile and non-endospore-forming. They were facultatively anaerobic, and oxidase- and catalase-positive. Their major isoprenoid quinone was Q-8, and their predominant fatty acids were C18 : 1ω7c, C16 : 1ω7c and C16 : 0. The DNA G+C content was 54.5 mol% in strain ZV-19 T and 45.8 mol% in strain R4-8T. The 16S rRNA gene based phylogenetic analysis showed that all three strains were members of the genus Nitrincola (family Oceanospirillaceae, class Gammaproteobacteria). Strain ZV-19T showed 96.6 and 95.5 % sequence similarities and 19±3 and 18±3 % DNA-DNA relatedness to Nitrincolalacisaponensis DSM 16316T and Nitrincolaalkalisediminis JCM 19317T, respectively. Strains R4-8T and S4-12 exhibited 97.9 and 98.6 % sequence matches and 34±4 and 13±8 % DNA-DNA hybridization values with N. lacisaponensis DSM 16316T and N. alkalisediminis JCM 19317T, respectively. According to the phenotypic, chemotaxonomic and phylogenetic data, the strains studied represent two novel species, Nitrincola alkalilacustris sp. nov. with the type strain ZV-19T (=DSM 29817T=NCAIM B 02612T) and Nitrincola schmidtii sp. nov. with the type strain R4-8T (=DSM 100788T=NCAIM B.02626T). An emended description of the genus Nitrincola is also presented.

Complete characterization of new isolates of Neptunomonas phycophila leads to emend its description and opens possibilities of biotechnological applications.

Five strains were isolated from gonad of Great scallop (Pecten maximus) broodstock in a Norwegian hatchery. The study of 16S rRNA gene sequences showed that these isolates belong to Neptunomonas phycophila, a bacterium originally isolated from a symbiont of the anemone Aiptasia tagetes from Puerto Rico. The gyrB and rpoB genes sequences confirmed the affiliation of the scallop isolates to this species. Phenotypic characterization was performed and some differences between the Norwegian isolates and the type strain of N. phycophila were detected, such as ranges of temperature, pH, and tolerance to salinity or the use of several substrates as sole carbon source which lead to an emended description of the species. The strain 3CM2.5 showed phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids. The whole genomes of the scallop strain 3CM2.5 and type strain of the species CECT 8716T were obtained and the annotation of these genomes revealed the presence of genes involved in degradation of aromatic compounds in both strains. Results obtained not only widen the geographical and host ranges of N. phycophila, but also point out possible biotechnological applications for this bacterial species.

Pontibacterium granulatum gen. nov., sp. nov., isolated from a tidal flat.

A Gram-stain-negative, strictly aerobic, moderately halophilic bacterium, designated A-1T, was isolated from a tidal flat of the Taean coast in South Korea. Cells were motile rods with a single flagellum showing oxidase-negative and catalase-positive activities and contained poly-ß-hydroxyalkanoic acid granules. Growth of strain A-1T was observed at 20-40 °C (optimum, 30 °C), pH 6.0-10.5 (optimum, pH 7.0) and in the presence of 1.0-6.0 % (w/v) NaCl (optimum, 2.0 %). Strain A-1T contained C16 : 0, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) as the major fatty acids. The major polar lipids of strain A-1T were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The isoprenoid quinones detected were ubiquinone-7 and ubiquinone-8. The G+C content of the genomic DNA was 51.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain A-1T formed a distinct phylogenetic lineage from other genera within the family Oceanospirillaceae. Strain A-1T shared low 16S rRNA gene sequence similarities with other taxa (≤94.9 %). On the basis of phenotypic, chemotaxonomic and molecular properties, it is clear that strain A-1T represents a novel genus and species of the family Oceanospirillaceae, for which the name Pontibacterium granulatum gen. nov., sp. nov. is proposed. The type strain is A-1T (=KACC 18119T=JCM 30136T).