Pontibacillus marinus sp. nov., a moderately halophilic bacterium from a solar saltern, and emended description of the genus Pontibacillus

Marine sediments in the Gulf of Gabes (Tunisia) heavily polluted by phosphogypsum and human microbiota bacteria: phytoremediation by Salicornia europaea as a natural-based solution

A huge amount of phosphogypsum (PG) wastes generated from the processing phosphate ore in Tunisia Industrial Group Area-Gabes is getting discarded into the sea. Within this framework, the basic objective of this research is to elaborate and discuss a natural-based solution focused on phytoremediation of contaminated (PG) soils and marine sediments with the halophilic plant Salicornia europaea. A significant drop of the organic matter (53.09%), moisture (26.47%), and sediment porosity with (5.88%) was detected in the rhizosphere Salicornia europaea area (RS). Removal of hazardous elements concentrations, such as Pb, Fe, Cu, Cd, and Zn, between contaminated sediment (CS) and RS displayed a significant difference, ranging from 5.33 to 50.02% of hazardous elements removal concentration, which was observed in the rhizosphere zone. The microbiota of both areas (RS and CS) were analyzed by massive sequencing. In both samples, all the sequences belong to only four phyla: Firmicutes and, to a much lower extent, Proteobacteria, Bacteroidetes, and Actinobacteria. The CS sediment seems to be heavily polluted by human activities. Most of the found genera are inhabitants of the intestine of warm-blooded animals (Escherichia, Bacteroides, Prevotella, Faecalibacterium, Ruminococcus, Enterococcus); hence, activities in this area pose a health risk. On the other hand, it may be surprising that 76.4% of the total high-quality sequences retrieved from the RS sample were affiliated to the family Bacillaceae. The salinity of the studied soil exerts a stress on the microbial populations that inhabit it, directing the selection of halotolerant species.

Comparative genomics reveals evidence of polycyclic aromatic hydrocarbon degradation in the moderately halophilic genus Pontibacillus

Polycyclic aromatic hydrocarbons (PAHs) are a common class of persistent organic pollutants (POPs) that are widely distributed in various environments and pose significant threats to both environmental and human health. The genus Pontibacillus, a type of moderately halophilic bacteria, has demonstrated potential for biodegrading aromatic compounds in high-salinity environments. However, no previous study has comprehensively investigated the PAH degradation mechanisms and environmental adaptability in the genus Pontibacillus. In this study, we sequenced the whole genome of the PAH-degrading strain Pontibacillus chungwhensis HN14 and conducted a comparative genomics analysis of genes associated with PAH degradation, as well as salt and arsenic tolerance using ten other Pontibacillus sp. strains. Here, we elucidated potential degradation pathways for benzo[a]pyrene and phenanthrene, which were initiated by cytochrome P450 monooxygenases, in most Pontibacillus strains. Moreover, four Pontibacillus strains were selected to investigate the biodegradation of benzo[a]pyrene and phenanthrene under high-salt (5% NaCl) stress, and all four strains exhibited exceptional degradation abilities. The results of comparative genomics and phenotypic analyses demonstrate that the genus Pontibacillus have the potential to degrade polycyclic aromatic hydrocarbons in high-salinity environments, thus providing valuable insights for biodegradation in extreme environments.

New robust subtilisins from halotolerant and halophilic Bacillaceae

The aim of the present study was the characterisation of three true subtilisins and one phylogenetically intermediate subtilisin from halotolerant and halophilic microorganisms. Considering the currently growing enzyme market for efficient and novel biocatalysts, data mining is a promising source for novel, as yet uncharacterised enzymes, especially from halophilic or halotolerant Bacillaceae, which offer great potential to meet industrial needs. Both halophilic bacteria Pontibacillus marinus DSM 16465^T and Alkalibacillus haloalkaliphilus DSM 5271^T and both halotolerant bacteria Metabacillus indicus DSM 16189 and Litchfieldia alkalitelluris DSM 16976^T served as a source for the four new subtilisins SPPM, SPAH, SPMI and SPLA. The protease genes were cloned and expressed in Bacillus subtilis DB104. Purification to apparent homogeneity was achieved by ethanol precipitation, desalting and ion-exchange chromatography. Enzyme activity could be observed between pH 5.0-12.0 with an optimum for SPPM, SPMI and SPLA around pH 9.0 and for SPAH at pH 10.0. The optimal temperature for SPMI and SPLA was 70 °C and for SPPM and SPAH 55 °C and 50 °C, respectively. All proteases showed high stability towards 5% (w/v) SDS and were active even at NaCl concentrations of 5 M. The four proteases demonstrate potential for future biotechnological applications. KEY POINTS: • Halophilic and halotolerant Bacillaceae are a valuable source of new subtilisins. • Four new subtilisins were biochemically characterised in detail. • The four proteases show potential for future biotechnological applications.

Pontibacillus sp. ALD_SL1 and Psychroflexus sp. ALD_RP9, two novel moderately halophilic bacteria isolated from sediment and water from the Aldabra Atoll, Seychelles

Pontibacillus sp. ALD_SL1 and Psychroflexus sp. ALD_RP9 are two novel bacterial isolates from mangrove sediment and a moderately hypersaline pool on the Aldabra Atoll, Seychelles. The isolates represent two novel species were characterised physiologically and genomically. Pontibacillus sp. ALD_SL1 is a facultatively anaerobic yellow, motile, rod-shaped Gram-positive, which grows optimally at a NaCl concentration of 11%, pH 7 and 28°C. It is the third facultatively anaerobic member of the genus Pontibacillus. The organism gains energy through the fermentation of pyruvate to acetate and ethanol under anaerobic conditions. The genome is the first among Pontibacillus that harbours a megaplasmid. Psychroflexus sp. ALD_RP9 is an aerobic heterotroph, which can generate energy by employing bacteriorhodopsins. It forms Gram-negative, orange, non-motile rods. The strain grows optimally at NaCl concentrations of 10%, pH 6.5–8 and 20°C. The Psychroflexus isolate tolerated pH conditions up to 10.5, which is the highest pH tolerance currently recorded for the genus. Psychroflexus sp. ALD_RP9 taxonomically belongs to the clade with the smallest genomes. Both isolates show extensive adaptations to their saline environments yet utilise different mechanisms to ensure survival.

A predator-prey interaction between a marine Pseudoalteromonas sp. and Gram-positive bacteria

Predator-prey interactions play important roles in the cycling of marine organic matter. Here we show that a Gram-negative bacterium isolated from marine sediments (Pseudoalteromonas sp. strain CF6-2) can kill Gram-positive bacteria of diverse peptidoglycan (PG) chemotypes by secreting the metalloprotease pseudoalterin. Secretion of the enzyme requires a Type II secretion system. Pseudoalterin binds to the glycan strands of Gram positive bacterial PG and degrades the PG peptide chains, leading to cell death. The released nutrients, including PG-derived D-amino acids, can then be utilized by strain CF6-2 for growth. Pseudoalterin synthesis is induced by PG degradation products such as glycine and glycine-rich oligopeptides. Genes encoding putative pseudoalterin-like proteins are found in many other marine bacteria. This study reveals a new microbial interaction in the ocean.

Predator-prey interactions play important roles in the cycling of marine organic matter. Here the authors show that a Gram-negative bacterium isolated from marine sediments can kill and feed on Gram-positive bacteria by secreting a peptidoglycan-degrading enzyme.

Microbial Diversity in an Arid, Naturally Saline Environment

The Arava Valley in is a rock desert within the Great African Rift valley. Soil from this area is covered with a salt crust. Here, we report microbial diversity from arid, naturally saline samples collected near Ein Yahav from the Arava Valley by culture-independent as well as culture-dependent analysis. High-throughput sequencing of the hypervariable region V4 of the 16S rRNA gene revealed that the microbial community consists of halophiles from the domain Bacteria as well as Archaea. Bacterial diversity was mainly represented by the genus Salinimicrobium of the order Flavobacteriales within the phylum Bacteroidetes, from the gammaproteobacterial orders Alteromonadales and Oceanospirillales as well as representatives from the order Bacillales of the phylum Firmicutes. Archaeal diversity was dominated by euryarchaeal Halobacteria from the orders Halobacteriales, Haloferacales, and Natrialbales. But more than 40% of the sequences affiliated with Archaea were assigned to unknown or unclassified archaea. Even if taxonomic resolution of the 16S rRNA gene V4 region for Archaea is limited, this study indicates the need of further and more detailed studies of Archaea. By using culture-dependent analysis, bacteria of the order Bacillales as well as archaea from all three halobacterial orders Halobacteriales, Haloferacales, and Natrialbales including potentially novel species from the genera Halorubrum and Haloparvum were isolated.

Pontibacillus salipaludis sp. nov., a slightly halophilic bacterium isolated from a salt pan

Two novel Gram-stain-positive, facultatively anerobic, rod-shaped, motile, endospore-forming bacterial strains, 9DMT and 6DM, were isolated from Tuticorn, India. The high 16S rRNA gene sequence similarity (99.9 %) and DNA-DNA relatedness (88±2 %) indicated that strains 9DMT and 6DM were members of a single species. Based on 16S rRNA gene sequence analysis these strains were identified as belonging to the genus Pontibacillus and were related most closely to the type strains of Pontibacillus chungwhensis (99.7 % sequence similarity) and Pontibacillus marinus (97.9 %). The DNA G+C content of strains 9DMT and 6DM was 41.6 and 41.4 mol%, respectively. However, the level of DNA-DNA relatedness of these strains with P. chungwhensis KCTC 3890T and P. marinus KCTC 3917T was only 40.9 + 0.8 and 39.8 + 0.9 %, respectively. Strains 9DMT and 6DM were facultative anaerobes with optimal growth at 37 °C, at pH 7.0-8.0 and with 2-3 % (w/v) NaCl. The cell-wall peptidoglycan of strain 9DMT contained meso-diaminopimelic acid. Polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, a phospholipid and three unknown lipids. The isoprenoid quinone was MK-7. Major fatty acids of strain 9DMT were anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The results of phylogenetic, chemotaxonomic and biochemical tests allowed the clear differentiation of strains 9DMT and 6DM, which are considered to represent a novel member of the genus Pontibacillus, for which the name Pontibacillus salipaludis sp. nov. is proposed. The type strain is 9DMT (= KCTC 33742T=LMG 29102T= CGMCC 1.15353T).

High quality draft genome sequence of the moderately halophilic bacterium Pontibacillus yanchengensis Y32(T) and comparison among Pontibacillus genomes

Pontibacillus yanchengensis Y32(T) is an aerobic, motile, Gram-positive, endospore-forming, and moderately halophilic bacterium isolated from a salt field. In this study, we describe the features of P. yanchengensis strain Y32(T) together with a comparison with other four Pontibacillus genomes. The 4,281,464 bp high-quality-draft genome of strain Y32(T) is arranged into 153 contigs containing 3,965 protein-coding genes and 77 RNA encoding genes. The genome of strain Y32(T) possesses many genes related to its halophilic character, flagellar assembly and chemotaxis to support its survival in a salt-rich environment.

Pontibacillus salicampi sp. nov., a moderately halophilic bacterium isolated from saltern soil

A Gram-stain-positive, moderately halophilic bacterium, designated BH043T, was isolated from saltern soil of Gomso in Korea. Cells were motile rods, producing ellipsoidal endospores at a terminal position in swollen sporangia. Strain BH043T was strictly aerobic, grew at pH 6.0–10.0 (optimal growth at pH 7.5), at 10–55 °C (optimal growth at 30 °C) and at salinities of 1–20 % (w/v) NaCl, growing optimally with 7 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain BH043T belongs to the family Bacillaceae and was most closely related to the type strains of the five recognized species of the genus Pontibacillus , showing sequence similarity to Pontibacillus yanchengensis Y32T (97.5 % similarity), Pontibacillus marinus BH030004T (97.4 %), Pontibacillus chungwhensis BH030062T (97.0 %), Pontibacillus litoralis JSM 072002T (96.4 %) and Pontibacillus halophilus JSM 076056T (96.2 %). The major cellular fatty acids of strain BH043T were iso-C15 : 0 and anteiso-C15 : 0. The genomic DNA G+C content was 42.5 mol%. The major isoprenoid quinone was MK-7 and meso-diaminopimelic acid was present in the cell-wall peptidoglycan as the diagnostic diamino acid. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. DNA–DNA relatedness between strain BH043T and the type strains of other species of the genus Pontibacillus , P. yanchengensis CGMCC 1.10680T and P. marinus KCTC 3917T and P. chungwhensis KCTC 3890T, was 35, 24 and 18 %, respectively. On the basis of polyphasic analysis from this study, strain BH043T represents a novel species of the genus Pontibacillus for which the name Pontibacillus salicampi sp. nov. is proposed. The type strain is BH043T ( = KACC 17607T = NBRC 109831T = NCAIM B.02529T).

Evolution in the Bacillaceae

The family Bacillaceae constitutes a phenotypically diverse and globally ubiquitous assemblage of bacteria. Investigation into how evolution has shaped, and continues to shape, this family has relied on several widely ranging approaches from classical taxonomy, ecological field studies, and evolution in soil microcosms to genomic-scale phylogenetics, laboratory, and directed evolution experiments. One unifying characteristic of the Bacillaceae , the endospore, poses unique challenges to answering questions regarding both the calculation of evolutionary rates and claims of extreme longevity in ancient environmental samples.

Pontibacillus yanchengensis sp. nov., a moderately halophilic bacterium isolated from salt field soil

A Gram-positive-staining, aerobic, moderately halophilic bacterium, designated strain Y32T, was isolated from subsurface soil of the Sanwei salt field, Yancheng, Jiangsu province, South-east China. The cell-wall peptidoglycan type of strain Y32T was meso-diaminopimelic acid. The menaquinone was menaquinone-7 (MK-7). The major fatty acids were anteiso-C15 : 0 and iso-C15 : 0 and the DNA G+C content of strain Y32T was 40.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Y32T was closely related to the type strains of the genus Pontibacillus. The 16S rRNA gene sequence similarities of strain Y32T with the type strains of species of the genus Pontibacillus were 97.8 % (Pontibacillus marinus KCTC 3917T), 96.9 % (Pontibacillus chungwhensis BH030062T), 96.8 % (Pontibacillus litoralis JSM 072002T) and 96.0 % (Pontibacillus halophilus JSM 076056T). DNA–DNA relatedness between strain Y32T and P. marinus KCTC 3917T was 42 %. On the basis of phenotypic, chemotaxonomic and phylogenetic evidences, strain Y32T was found to be affiliated to the genus Pontibacillus, but was clearly differentiated from other members of this genus. Strain Y32T represents a novel member of the genus, for which the name Pontibacillus yanchengensis sp. nov. is proposed. The type strain is Y32T ( = CGMCC 1.10680T = CCTCC AB209311T = NRRL B-59408T).

Pontibacillus litoralis sp. nov., a facultatively anaerobic bacterium isolated from a sea anemone, and emended description of the genus Pontibacillus

A facultatively anaerobic, moderately halophilic, Gram-positive, endospore-forming, motile, catalase- and oxidase-positive, rod-shaped bacterium, strain JSM 072002T, was isolated from a sea anemone (Anthopleura xanthogrammica) collected from the South China Sea. Strain JSM 072002T was able to grow with 0.5–15 % (w/v) NaCl and at pH 6.0–10.0 and 15–50 °C; optimum growth was observed with 2–5 % (w/v) NaCl and at pH 7.5 and 35 °C. meso-Diaminopimelic acid was present in the cell-wall peptidoglycan. The major cellular fatty acids were iso-C15 : 0 and anteiso-C15 : 0. The predominant respiratory quinone was menaquinone 7 and the genomic DNA G+C content was 41.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain JSM 072002T should be assigned to the genus Pontibacillus and revealed relatively low 16S rRNA gene sequence similarities (<97 %) with the type strains of the three recognized Pontibacillus species (Pontibacillus chungwhensis BH030062T, 96.8 %; Pontibacillus marinus KCTC 3917T, 96.7 %; Pontibacillus halophilus JSM 076056T, 96.0 %). The combination of phylogenetic analysis, DNA–DNA relatedness values, phenotypic characteristics and chemotaxonomic data supports the view that strain JSM 072002T represents a novel species of the genus Pontibacillus, for which the name Pontibacillus litoralis sp. nov. is proposed. The type strain is JSM 072002T (=DSM 21186T=KCTC 13237T). An emended description of the genus Pontibacillus is also presented.

Brevundimonas aveniformis sp. nov., a stalked species isolated from activated sludge

A Gram-negative, rod-like, stalk-producing bacterium, designated strain EMB102(T), was isolated from activated sludge that performed enhanced biological phosphorus removal in a sequencing batch reactor. Cells without stalks were motile with single polar flagella, but cells that did produce stalks were non-motile and lacked polar flagella. Growth of strain EMB102(T) was observed at temperatures between 15 and 35 degrees C (optimum, 30 degrees C) and between pH 6.0 and 9.0 (optimum, pH 7.5-8.5). The predominant fatty acids of strain EMB102(T) were C(18 : 1) omega 7c, C(16 : 0) and C(15 : 0). The predominant polar lipid was phosphatidylglycerol. The G+C content of the genomic DNA was 64.1 mol% and the major quinone was Q-10. Comparative 16S rRNA gene sequence analyses showed that strain EMB102(T) formed a distinct phyletic lineage within the genus Brevundimonas. The levels of 16S rRNA gene sequence similarity between the type strains of Brevundimonas species ranged from 95.8 to 97.5 %. DNA-DNA relatedness levels between the EMB102(T) and closely related Brevundimonas species were below 15.0 %. On the basis of chemotaxonomic data and molecular properties, strain EMB102(T) represents a novel species within the genus Brevundimonas, for which the name Brevundimonas aveniformis sp. nov. is proposed. The type strain is EMB102(T) (=KCTC 12609(T)=DSM 17977(T)).

Alkalibacillus halophilus sp. nov., a new halophilic species isolated from hypersaline soil in Xin-Jiang province, China

A halophilic, Gram-positive, spore-forming motile Bacillus-like strain YIM 012(T), was isolated from one of the hypersaline soil samples collected in Xin-jiang province, China. Its optimum growth occurred at 10-20% of NaCl concentration (w/v), pH 7.0-8.0. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 012(T) is a member of the genus of Alkalibacillus, which is well supported by its chemotaxonomic and molecular characteristics. Based on its phenotypic evidence and genotypic data, Alkalibacillus halophilus sp. nov. was proposed and strain YIM 012(T) (=DSM 17369(T)=KCTC 3990(T)) was assigned as the type strain of the novel species.

Hydrogenophaga caeni sp. nov., isolated from activated sludge

A Gram-negative bacterium, designated strain EMB71T, was isolated from activated sludge used for enhanced biological phosphorus removal in a sequencing batch reactor. The cells of the isolate were facultatively aerobic, motile rods with single polar flagella. Growth was observed to occur at 15–35 °C (optimally at 30 °C) and at pH 6.0–9.0 (optimally at pH 7.0–8.0). The predominant fatty acids of strain EMB71T were C16 : 0 and summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH), and the polar lipids comprised a large amount of phosphatidylethanolamine and a small amount of diphosphatidylglycerol. The G+C content of the genomic DNA was 61.6 mol % and the major quinone was Q-8. Comparative 16S rRNA gene sequence analyses showed that strain EMB71T formed a phyletic lineage with the genus Hydrogenophaga within the family Comamonadaceae. The levels of 16S rRNA gene sequence similarity with respect to the type strains of Hydrogenophaga species ranged from 95.1 to 96.9 %. On the basis of the phenotypic, chemotaxonomic and molecular data, strain EMB71T represents a novel species of the genus Hydrogenophaga, for which the name Hydrogenophaga caeni sp. nov. is proposed. The type strain is EMB71T (=KCTC 12613T=DSM 17962T).

Flavobacterium defluvii sp. nov., isolated from activated sludge

A Gram-negative bacterium, designated strain EMB117T, was isolated from a municipal wastewater treatment plant and characterized by polyphasic taxonomy. The cells were non-spore-forming rods that showed gliding motility. Optimal growth occurred at 25–30 °C and pH 7.0–8.0. Strain EMB117T contained phosphatidylethanolamine as the predominant polar lipid, and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH). The G+C content of the genomic DNA was 33.5 mol% and the major isoprenoid quinone was MK-6. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain EMB117T belonged to the genus Flavobacterium and was most closely related to Flavobacterium johnsoniae DSM 425T (97.8 % sequence similarity). The DNA–DNA relatedness between strain EMB117T and F. johnsoniae ATCC 17061T was about 18 %. On the basis of the phenotypic, chemotaxonomic and molecular data, strain EMB117T represents a novel species within the genus Flavobacterium, for which the name Flavobacterium defluvii sp. nov. is proposed. The type strain is EMB117T (=KCTC 12612T=DSM 17963T).

Terribacillus saccharophilus gen. nov., sp. nov. and Terribacillus halophilus sp. nov., spore-forming bacteria isolated from field soil in Japan

Three strains, 002-048T, RB589 and 002-051T, isolated from field soil in Japan, were characterized using a polyphasic approach. The isolates were Gram-positive, strictly aerobic, non-motile rods that formed ellipsoidal, subterminal endospores. The chemotaxonomic characteristics of these isolates included the presence of meso-diaminopimelic acid as the cell-wall peptidoglycan, anteiso-C15 : 0 and anteiso-C17 : 0 as the major cellular fatty acids and MK-7 as the predominant menaquinone. The DNA G+C content was 44–46 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the isolates represented an independent lineage that is distinct from related taxa and exhibited less than 94.3 % sequence similarity with respect to those taxa. Moreover, a DNA–DNA hybridization analysis showed that the three isolates represented two species. On the basis of their phenotypic and phylogenetic distinctiveness, the isolates represent two species within a novel genus, for which the names Terribacillus saccharophilus gen. nov., sp. nov. and Terribacillus halophilus sp. nov. are proposed. The type strain of T. saccharophilus is 002-048T (=IAM 15309T=KCTC 13936T) and the type strain of T. halophilus is 002-051T (=IAM 15310T=KCTC 13937T).

Simplicispira limi sp. nov., isolated from activated sludge

A Gram-negative, motile, rod-shaped bacterium, designated strain EMB325T, was isolated from activated sludge that performed enhanced biological phosphorus removal in a sequencing batch reactor. The predominant fatty acids of strain EMB325T were summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH), C16 : 0, C18 : 1 ω7c and C18 : 1 ω7c 11-methyl. The strain contained phosphatidylethanolamine and diphosphatidylglycerol as polar lipids. The G+C content of the genomic DNA was 63.3 mol%. The major quinone was Q-8. Phylogenetic analysis of 16S rRNA gene sequences showed that strain EMB325T formed a phyletic lineage with members of the genus Simplicispira and was most closely related to Simplicispira psychrophila LMG 5408T and Simplicispira metamorpha DSM 1837T with similarities of 98.1 and 97.9 %, respectively. Levels of DNA–DNA relatedness between strain EMB325T and S. psychrophila LMG 5408T and S. metamorpha DSM 1837T were 28 and 23 %, respectively. On the basis of chemotaxonomic data and molecular characteristics, strain EMB325T is considered to represent a novel species within the genus Simplicispira, for which the name Simplicispira limi sp. nov. is proposed. The type strain is EMB325T (=KCTC 12608T=DSM 17964T).

Bacillus taeanensis sp. nov., a halophilic Gram-positive bacterium from a solar saltern in Korea

A halophilic bacterium, strain BH030017T, showing optimum growth at 2–5 % (w/v) NaCl was isolated from solar-saltern sediment from the Tae-An area of Korea and was characterized taxonomically. The cells of strain BH030017T were Gram-positive, motile, short rods containing cell-wall peptidoglycan based on meso-diaminopimelic acid. The major cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The DNA G+C content was 36 mol% and the predominant lipoquinone was MK-7. The major cellular phospholipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain BH030017T formed a cluster with Bacillus clarkii DSM 8720T and Bacillus agaradhaerens DSM 8721T within the family Bacillaceae. 16S rRNA gene sequence similarities with respect to closely related type strains were less than 95.1 %. On the basis of its phylogenetic, phenotypic and chemotaxonomic properties, strain BH030017T represents a novel species within the genus Bacillus, for which the name Bacillus taeanensis sp. nov. is proposed. The type strain is BH030017T (=KCTC 3918T=DSM 16466T).

Paenibacillus xinjiangensis sp. nov., isolated from Xinjiang province in China

Strain B538T is a Gram-positive, motile, rod-shaped bacterium, which was isolated from Xinjiang province in China. This organism grew optimally at 30–35 °C and pH 8.0–8.5. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain B538T belonged to the genus Paenibacillus and chemotaxonomic data (DNA G+C content, 47.0 mol%; major isoprenoid quinone, MK-7; cell wall type, A1γ meso-diaminopimelic acid; major fatty acids, anteiso-C15 : 0 and C16 : 0) supported affiliation of the isolate with the genus Paenibacillus. Comparative 16S rRNA gene sequence analyses showed that the isolate was most closely related to Paenibacillus glycanilyticus DS-1T, with 16S rRNA gene sequence similarity of 98.1 %; sequence similarities to other members of the genus Paenibacillus used in the phylogenetic tree were less than 96.5 %. The DNA–DNA relatedness between strain B538T and P. glycanilyticus DS-1T was about 8.0 %. On the basis of physiological and molecular properties, strain B538T (=KCTC 3952T=DSM 16970T) is proposed as the type strain of a novel species within the genus Paenibacillus, for which the name Paenibacillus xinjiangensis sp. nov. is proposed.

Gracilibacillus orientalis sp. nov., a novel moderately halophilic bacterium isolated from a salt lake in Inner Mongolia, China

Three Gram-positive, moderately halophilic, spore-forming rods, designated XH-63T, XH-62 and EJ-15, were isolated from two salt lakes located near Xilin Hot and Ejinor, in Inner Mongolia, China. The strains were strictly aerobic and motile, with spherical, terminal and deforming endospores. They grew at pH 5·0–9·0 (optimal growth at pH 7·5), between 4 and 45 °C (optimal growth at 37 °C) and at salinities of 1–20 % (w/v) total salts, growing optimally at 10 % (w/v) salts. They hadmeso-diaminopimelic acid in the cell wall peptidoglycan and DNA G+C contents of 36·1–37·1 mol%. The polar lipid pattern of strain XH-63T, selected as the representative strain, consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and a phospholipid and two amino phospholipids of unknown structure. This strain possessed anteiso-C15 : 0and anteiso-C17 : 0as the major fatty acids (altogether representing 72·5 % of total) and MK-7 as the major menaquinone. 16S rRNA gene analysis of the three strains showed that they were within theGracilibacilluscluster, with highest sequence similarity (95·4–95·8 %) withGracilibacillus dipsosauri. Based on a combination of phenotypic, chemotaxonomic and phylogenetic features, it is proposed that the three isolates represent a novel species of the genusGracilibacillus,Gracilibacillus orientalissp. nov. The type strain is strain XH-63T(=CCM 7326T=AS 1.4250T=CECT 7097T).

Thalassobacillus devorans gen. nov., sp. nov., a moderately halophilic, phenol-degrading, Gram-positive bacterium

A novel moderately halophilic bacterium, strain G-19.1T, has been isolated from a phenol enrichment of samples collected in hypersaline habitats of southern Spain. This enrichment culture was a part of a screening programme to isolate halophilic bacteria able to degrade various aromatic compounds. Strain G-19.1T has been characterized as a potential phenol-degrader over a wide range of saline conditions. Strain G-19.1T was found to be an aerobic, Gram-positive, endospore-forming, non-pigmented, moderately halophilic rod that grew optimally in media containing 7·5–10 % NaCl at pH 7·0. The DNA G+C content was 42·4 mol%. Phylogenetic analysis based on comparison of 16S rRNA gene sequences indicated that the closest relatives were Halobacillus species (96·2–97·0 %), although this novel isolate constitutes a separate line of descent within the radiation of Gram-positive rods. The cell-wall peptidoglycan contained meso-diaminopimelic acid, indicating that this strain does not share the main characteristic that differentiates members of the genus Halobacillus (which contain Orn–d-Asp) from other related genera. The predominant cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0 and iso-C15 : 0. On the basis of phenotypic, genotypic and phylogenetic analyses, this isolate should be classified in a novel genus and species, for which the name Thalassobacillus devorans gen. nov., sp. nov. is proposed. The type strain is strain G-19.1T (=DSM 16966T=CECT 7046T=CCM 7282T).