Halomonas saccharevitans sp. nov., Halomonas arcis sp. nov. and Halomonas subterranea sp. nov., halophilic bacteria isolated from hypersaline environments of China

Halomonas pelophila sp. nov., isolated from mud and Halomonas aquatica sp. nov., isolated from marine water

Two Gram-negative, catalase- and oxidase-positive, cream-coloured, short rod-shaped, and motile bacterial strains, designated CS7T and SSM6T, were isolated from mud and marine water collected in Incheon, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that both strains belonged to the genus Halomonas. Strain CS7T exhibited the highest 16S rRNA similarity with Halomonas urmiana TBZ3T (99.0%), while strain SSM6T exhibited the highest 16S rRNA similarity with Halomonas saccharevitans AJ275T (98.4%). Strain CS7T was observed at temperatures ranging from 4 to 44 °C (optimum, 30 °C), at pH levels from 2.0 to 12.0 (optimum, pH 8-9), and in NaCl concentrations of 0-23% (w/v) (optimum, 9%). Strain SSM6T was observed at temperatures ranging from 4 to 37 °C (optimum, 30 °C), at pH levels from 2.0 to 10.0 (optimum, pH 8-9), and in NaCl concentrations of 0% to 23% (w/v) (optimum, 9%). The DNA G + C content of CS7T was 67.7 mol%, while that of SSM6T was 65.1 mol%. Strains CS7T and SSM6T were identified to possess phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and diphosphatidylglycerol (DPG) as the major polar lipids. Predominant fatty acids (> 10%) in strain CS7T were C16:0, C12:0 3-OH, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c). Predominant fatty acids (> 10%) in strain SSM6T were C16:0, C12:0 3-OH, cyclo-C19:0 ω8c, and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c). Based on phylogenetic, physicochemical, and biochemical data, CS7T and SSM6T represent novel species within the genus Halomonas. They have been designated as Halomonas pelophila sp. nov. (= KACC 23728T = TBRC 19017T) and Halomonas aquatica sp. nov. (= KACC 23729T = TBRC 19018T).

A long-awaited taxogenomic investigation of the family Halomonadaceae

The family Halomonadaceae is the largest family composed of halophilic bacteria, with more than 160 species with validly published names as of July 2023. Several classifications to circumscribe this family are available in major resources, such as those provided by the List of Prokaryotic names with Standing in Nomenclature (LPSN), NCBI Taxonomy, Genome Taxonomy Database (GTDB), and Bergey's Manual of Systematics of Archaea and Bacteria (BMSAB), with some degree of disagreement between them. Moreover, regardless of the classification adopted, the genus Halomonas is not phylogenetically consistent, likely because it has been used as a catch-all for newly described species within the family Halomonadaceae that could not be clearly accommodated in other Halomonadaceae genera. In the past decade, some taxonomic rearrangements have been conducted on the Halomonadaceae based on ribosomal and alternative single-copy housekeeping gene sequence analysis. High-throughput technologies have enabled access to the genome sequences of many type strains belonging to the family Halomonadaceae; however, genome-based studies specifically addressing its taxonomic status have not been performed to date. In this study, we accomplished the genome sequencing of 17 missing type strains of Halomonadaceae species that, together with other publicly available genome sequences, allowed us to re-evaluate the genetic relationship, phylogeny, and taxonomy of the species and genera within this family. The approach followed included the estimate of the Overall Genome Relatedness Indexes (OGRIs) such as the average amino acid identity (AAI), phylogenomic reconstructions using amino acid substitution matrices customized for the family Halomonadaceae, and the analysis of clade-specific signature genes. Based on our results, we conclude that the genus Halovibrio is obviously out of place within the family Halomonadaceae, and, on the other hand, we propose a division of the genus Halomonas into seven separate genera and the transfer of seven species from Halomonas to the genus Modicisalibacter, together with the emendation of the latter. Additionally, data from this study demonstrate the existence of various synonym species names in this family.

Parerythrobacter lacustris sp. nov., a novel member of the family Erythrobacteraceae isolated from an inland alpine lake

A novel bacterium, designated as strain RS5-5T, was isolated from lake water in northwestern China. Cells of the isolate were observed to be rod shaped and Gram stain negative. Its growth occurred at 4-37 ℃, pH 6.5-9.0 and in the presence of 0-5% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain RS5-5T was most closely related to Qipengyuania sediminis GDMCC 1.2497T (97.5%), followed by Erythrobacter dokdonensis DSW-74T (97.3%) and Qipengyuania algicida GDMCC 1.2535T (97.0%). Phylogenomic analysis revealed that strain RS5-5T formed a distinct branch with the genus Parerythrobacter. The sole quinone was ubiquinone-10, and the major fatty acids (≥ 10%) were unsaturated fatty acids including C17:1 ω6c, summed feature 3 (C16:1 ω7c/C16:1 ω6c) and summed feature 8 (C18:1 ω7c/C18:1 ω6c). The polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, one unidentified sphingoglycolipid, three unidentified glycolipids, one unidentified aminoglycolipid, one unidentified aminolipid, two unidentified phospholipids and four unidentified polar lipids. Chemotaxonomic characteristics of strain RS5-5T were coincident with those of the genus Parerythrobacter members. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between strain RS5-5T and two Parerythrobacter reference strains were in the ranges of 73.2-77.7%, 69.0-78.0% and 18.9-20.4%, respectively. The genomic DNA G + C content of strain RS5-5T was 64.1%. The results of phenotypic, phylogenetic and genomic analyses suggested that strain RS5-5T represents a novel species in the genus Parerythrobacter, for which the name Parerythrobacter lacustris sp. nov. is proposed. The type strain is RS5-5T (= GDMCC 1.3163T = KCTC 92277T).

Halomonas gemina sp. nov. and Halomonas llamarensis sp. nov., two siderophore-producing organisms isolated from high-altitude salars of the Atacama Desert

Introduction

This study aimed to identify and characterize novel siderophore-producing organisms capable of secreting high quantities of the iron-binding compounds. In the course of this, two not yet reported halophilic strains designated ATCHA^T and ATCH28^T were isolated from hypersaline, alkaline surface waters of Salar de Llamará and Laguna Lejía, respectively. The alkaline environment limits iron bioavailability, suggesting that native organisms produce abundant siderophores to sequester iron.

Methods

Both strains were characterized by polyphasic approach. Comparative analysis of the 16S rRNA gene sequences revealed their affiliation with the genus Halomonas. ATCHA^T showed close similarity to Halomonas salicampi and Halomonas vilamensis, while ATCH28^T was related closest to Halomonas ventosae and Halomonas salina. The ability of both strains to secrete siderophores was initially assessed using the chromeazurol S (CAS) liquid assay and subsequently further investigated through genomic analysis and NMR. Furthermore, the effect of various media components on the siderophore secretion by strain ATCH28^T was explored.

Results

The CAS assay confirmed the ability of both strains to produce iron-binding compounds. Genomic analysis of strain ATCHA^T revealed the presence of a not yet reported NRPS-dependant gene cluster responsible for the secretion of siderophore. However, as only small amounts of siderophore were secreted, further investigations did not lie within the scope of this study. Via NMR and genomic analysis, strain ATCH28^T has been determined to produce desferrioxamine E (DFOE). Although this siderophore is common in various terrestrial microorganisms, it has not yet been reported to occur within Halomonas, making strain ATCH28^T the first member of the genus to produce a non-amphiphilic siderophore. By means of media optimization, the produced quantity of DFOE could be increased to more than 1000 µM.

Discussion

Phenotypic and genotypic characteristics clearly differentiated both strains from other members of the genus Halomonas. Average nucleotide identity (ANI) values and DNA-DNA relatedness indicated that the strains represented two novel species. Therefore, both species should be added as new representatives of the genus Halomonas, for which the designations Halomonas llamarensis sp. nov. (type strain ATCHA^T = DSM 114476 = LMG 32709) and Halomonas gemina sp. nov. (type strain ATCH28^T = DSM 114418 = LMG 32708) are proposed.

Sandaracinobacteroides sayramensis sp. nov., a yellow-pigmented bacterium isolated from lake water

A Gram-negative, non-motile, facultatively anaerobic, rod-shaped bacterium, designated strain RS1-74^T, was isolated from the surface water of Sayram Lake, Xinjiang Uygur Autonomous Region, China. The strain was able to grow optimally at 30 °C and pH 7.0-7.5, and in the presence of 0-0.5 % (v/w) NaCl. Catalase and oxidase activities were present. H₂S was produced. Chemotaxonomic analysis showed Q-10 was the sole respiratory quinone. The polar lipids were composed of phosphatidylethanolamine, diphosphatidylglycerol, two glycolipids, phosphatidylglycerol, sphingoglycolipid and two unidentified lipids. Summed feature 3 (C_16 : 1  ω7c and/or C_16 : 1  ω6c) and summed feature 8 (C_18 : 1  ω7c and/or C_18 : 1  ω6c) were the predominant fatty acids. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain RS1-74^T was closely related to 'Sandaracinobacter neustonicus' JCM 30 734 (98.65 %), 'Sandaracinobacter sibiricus' RB16-17 (98.42 %) and Sandaracinobacteroides hominis SZY PN-1^T (97.09%). The genomic DNA G+C content was 66.45 mol%. The average nucleotide identity and DNA-DNA hybridization values among the genomes of strain RS1-74^T and 'Sandaracinobacter neustonicus' JCM 30734 and Sandaracinobacteroides hominis SZY PN-1^T were 78.2 and 77.22 %, and 22.2 and 20.40 %, respectively. Based on the physiological, biochemical, phylogenetic and genomic data, strain RS1-74^T represents a novel species within the genus Sandaracinobacteroides, for which the name Sandaracinobacteroides sayramensis sp. nov. is proposed, with type strain RS1-74^T (=KCTC 82674^T=MCCC 1K06282^T).

Finding of Novel Galactose Utilizing Halomonas sp. YK44 for Polyhydroxybutyrate (PHB) Production

Polyhydroxybutyrate (PHB) is a biodegradable bioplastic with potential applications as an alternative to petroleum-based plastics. However, efficient PHB production remains difficult. The main cost of PHB production is attributed to carbon sources; hence, finding inexpensive sources is important. Galactose is a possible substrate for polyhydroxyalkanoate production as it is abundant in marine environments. Marine bacteria that produce PHB from galactose could be an effective resource that can be used for efficient PHB production. In this study, to identify a galactose utilizing PHB producer, we examined 16 Halomonas strains. We demonstrated that Halomonas cerina (Halomonas sp. YK44) has the highest growth and PHB production using a culture media containing 2% galactose, final 4% NaCl, and 0.1% yeast extract. These culture conditions yielded 8.98 g/L PHB (78.1% PHB content (w/w)). When galactose-containing red algae (Eucheuma spinosum) hydrolysates were used as a carbon source, 5.2 g/L PHB was produced with 1.425% galactose after treatment with activated carbon. Since high salt conditions can be used to avoid sterilization, we examined whether Halomonas sp. YK44 could produce PHB in non-sterilized conditions. Culture media in these conditions yielded 72.41% PHB content. Thus, Halomonas sp. YK44 is robust against contamination, allowing for long-term culture and economical PHB production.

Description of two novel anaerobic members in the family Clostridiaceae, Anaeromonas gelatinilytica gen.nov., sp. nov., and Anaeromonas frigoriresistens sp. nov., isolated from saline lake sediment

Cells of members of the family Clostridiaceae , phylum Firmicutes , are generally obligate anaerobic rods. Strains D2Q-14T and D2Q-11T were isolated from sediment of the saline lake Manisi in the Xinjiang Uygur Autonomous Region, PR China. In this study, we employed a polyphasic approach and whole genome analysis of the two isolates. Cells of both isolates were Gram-stain-positive rods that were motile by means of flagella and could utilize sulphate, thiosulphate, elemental sulphur and nitrate as electron acceptors. Phylogenetic analyses based on 16S rRNA gene and whole genome sequences indicated that strains D2Q-14T and D2Q-11T constituted a coherent cluster affiliated to the family Clostridiaceae . In addition, genome analysis revealed that strain D2Q-14Tharboured one nonribosomal peptide synthetase gene cluster, making up 1.4 % of the entire genome. The genome-based analysis, including average nucleotide identity, average amino acid identity and in silico DNA–DNA hybridization, biochemical, phenotypic and chemotaxonomic characterization, indicated that strains D2Q-14T and D2Q-11T represented two novel species of a novel genus in the family Clostridiaceae , for which we propose the names Anaeromonas gelatinilytica gen. nov., sp. nov. and Anaeromonas frigoriresistens sp. nov., with the type strains D2Q-14T (=KCTC 15986T=MCCC 1K04634T) and D2Q-11T (=KCTC 15985T=MCCC 1K04391T), respectively.

Physiological and genomic features of Henriciella with the description of Henriciella mobilis sp. nov

Strains M65^T, M69 and JN25 were isolated from seawater of the West Pacific Ocean. Cells of the three strains were Gram-stain-negative, aerobic and rod-shaped. Cells were motile by means of flagella. On the basis of the results of 16S rRNA gene sequence analysis, strains M65^T, M69 and JN25 showed the highest 16S rRNA gene sequence similarity to Henriciella algicola MCS27^T (98.8 %), followed by Henriciella marina DSM 19595^T (98.4 %), Henriciella barbarensis MCS23^T (98.4 %), Henriciella pelagia LA220^T (98.3 %), Henriciella aquimarina P38^T (98.1 %) and Henriciella litoralis SD10^T (97.8 %). The 16S rRNA gene sequence similarities among the isolates were 100 %. Phylogenetic analyses revealed that the isolates fell within a cluster comprising the Henriciella species and represented an independent lineage. The average nucleotide identity and in silico DNA-DNA hybridization values between strain M65^T and the type strains of Henriciella species were 73.9-85.8 % and 19.9-22.4 %, respectively. The sole respiratory quinone detected in the three isolates was ubiquinone 10. The principal fatty acids were summed feature 8 (C_18 : 1  ω7c and/or C_18 : 1  ω6c) and C_16 : 0. The major polar lipids were glucuronopyranosyldiglyceride, monoglycosyldiglyceride and one unidentified glycolipid. The DNA G+C content was 61.3-61.4 mol%. Phylogenetic distinctiveness, chemotaxonomic differences, together with phenotypic properties, revealed that the isolates could be differentiated from the Henriciella species with validly published names. Therefore, it is proposed that strains M65^T, M69 and JN25 represent a novel species of the genus Henriciella, for which the name Henriciella mobilis sp. nov. (type strain, M65^T=CGMCC 1.15927^T=KCTC 52576^T) is proposed.

Microbial Degradation of Citric Acid in Low Level Radioactive Waste Disposal: Impact on Biomineralization Reactions

Organic complexants are present in some radioactive wastes and can challenge waste disposal as they may enhance subsurface mobility of radionuclides and contaminant species via chelation. The principal sources of organic complexing agents in low level radioactive wastes (LLW) originate from chemical decontamination activities. Polycarboxylic organic decontaminants such as citric and oxalic acid are of interest as currently there is a paucity of data on their biodegradation at high pH and under disposal conditions. This work explores the biogeochemical fate of citric acid, a model decontaminant, under high pH anaerobic conditions relevant to disposal of LLW in cementitious disposal environments. Anaerobic microcosm experiments were set up, using a high pH adapted microbial inoculum from a well characterized environmental site, to explore biodegradation of citrate under representative repository conditions. Experiments were initiated at three different pH values (10, 11, and 12) and citrate was supplied as the electron donor and carbon source, under fermentative, nitrate-, Fe(III)- and sulfate- reducing conditions. Results showed that citrate was oxidized using nitrate or Fe(III) as the electron acceptor at > pH 11. Citrate was fully degraded and removed from solution in the nitrate reducing system at pH 10 and pH 11. Here, the microcosm pH decreased as protons were generated during citrate oxidation. In the Fe(III)-reducing systems, the citrate removal rate was slower than in the nitrate reducing systems. This was presumably as Fe(III)-reduction consumes fewer moles of citrate than nitrate reduction for the same molar concentrations of electron acceptor. The pH did not change significantly in the Fe(III)-reducing systems. Sulfate reduction only occurred in a single microcosm at pH 10. Here, citrate was fully removed from solution, alongside ingrowth of acetate and formate, likely fermentation products. The acetate and lactate were subsequently used as electron donors during sulfate-reduction and there was an associated decrease in solution pH. Interestingly, in the Fe(III) reducing experiments, Fe(II) ingrowth was observed at pH values recorded up to 11.7. Here, TEM analysis of the resultant solid Fe-phase indicated that nanocrystalline magnetite formed as an end product of Fe(III)-reduction under these extreme conditions. PCR-based high-throughput 16S rRNA gene sequencing revealed that bacteria capable of nitrate Fe(III) and sulfate reduction became enriched in the relevant, biologically active systems. In addition, some fermentative organisms were identified in the Fe(III)- and sulfate-reducing systems. The microbial communities present were consistent with expectations based on the geochemical data. These results are important to improve long-term environmental safety case development for cementitious LLW waste disposal.

Halomonas maris sp. nov., a moderately halophilic bacterium isolated from sediment in the southwest Indian Ocean

A halophilic, Gram-staining-negative, rod-shaped, flagellated and motile bacterium, strain QX-1 ^T, was isolated from deep-sea sediment at a depth of 3332 m in the southwestern Indian Ocean. Strain QX-1 ^T growth was observed at 4-50 °C (optimum 37 °C), pH 5.0-11.0 (optimum pH 7.0), 3-25% NaCl (w/v; optimum 7%), and it did not grow without NaCl. A phylogenetic analysis based on the 16S rRNA gene placed strain QX-1 ^T in the genus Halomonas and most closely related to Halomonas sulfidaeris (97.9%), Halomonas zhaodongensis (97.8%), Halomonas songnenensis (97.6%), Halomonas hydrothermalis (97.4%), Halomonas subterranea (97.3%), Halomonas salicampi (97.1%), and Halomonas arcis (97.0%). DNA-DNA hybridization (< 26.5%) and average nucleotide identity values (< 83.5%) between strain QX-1 ^T and the related type strains meet the accepted criteria for a new species. The principal fatty acids (> 10%) of strain QX-1 ^T are C_16:0 (25.5%), C_17:0 cyclo (14.0%), C_19:0 cyclo ω8c (18.7%), and summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c, 18.1%). The polar lipids of strain QX-1 ^T are mainly diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified phospholipid, unidentified aminophospholipid, and five unidentified lipids. The main respiratory quinone is Q-9. The G + C content of its chromosomal DNA is 54.4 mol%. Its fatty acid profile, respiratory quinones, and G + C content also support the placement of QX-1 ^T in the genus Halomonas. These phylogenetic, phenotypic, and chemotaxonomic analyses indicate that QX-1 ^T is a novel species, for which the name Halomonas maris is proposed. The type strain is QX-1 ^T (= MCCC 1A17875^T = KCTC 82198 ^T = NBRC 114670 ^T).

Halomonas azerbaijanica sp. nov., a halophilic bacterium isolated from Urmia Lake after the 2015 drought

A novel, slightly halophilic bacterium, designated TBZ202^T, was isolated from water of Urmia Lake, in the Azerbaijan region of north-west Iran. The strain was facultatively anaerobic, Gram-stain-negative, rod-shaped and motile. Colonies were creamy, circular, convex and shiny. It grew at NaCl concentrations of 0-12 % (w/v) (optimum 3-5 % w/v), at temperatures of 20-45 °C (optimum 30 °C) and at pH 5.0-10.0 (optimum pH 7.0). Based on the 16S rRNA gene sequence, strain TBZ202^T belongs to the genus Halomonas in the Halomonadaceae and the most closely related species are Halomonas gudaonensis CGMCC 1.6133^T (98.6 % similarity), Halomonas ventosae Al12^T (96.8 %) and Halomonas rambilicola RS-16^T (96.6%). The G+C content was 67.9 % and the digital DNA-DNA hybridization and average nucleotide identity values with H. gudaonensis were 35.8 and 83.8 %, respectively, indicating that the isolate differs from all species described. The major fatty acids were C_{18 : 1} ω7c, C_{16 : 0} and C_{16 : 1} ω7c. The only respiratory quinone detected was Q-9 and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, aminophospholipid and three unknown phospholipids. On the basis of a polyphasic taxonomic analysis, the isolate is considered to represent a novel species of the genus Halomonas, for which the name Halomonas azerbaijanica sp. nov. is proposed. The type strain is TBZ202^T (=KCTC 62817^T=CECT 9693^T).

Halomonas urmiana sp. nov., a moderately halophilic bacterium isolated from Urmia Lake in Iran

In the course of screening halophilic bacteria in Urmia Lake in Iran, which is being threatened by dryness, a novel Gram-negative, moderately halophilic, heterotrophic and short rod-shaped bacteria was isolated and characterized. The bacterium was isolated from a water specimen and designated as TBZ3^T. Colonies were found to be creamy yellow, with catalase- and oxidase-positive activities. The growth of strain TBZ3^T was observed to be at 10-45 °C (optimum, 30 °C), at pH 6.0-9.0 (optimum, pH 7.0) and in the presence of 0.5-20 % (w/v) NaCl (optimum, 7.5 %). Strain TBZ3^T contained C_16 : 0, cyclo-C_19 : 0  ω8c, summed feature 3 (comprising C_16 : 1  ω7c and/or C_16 : 1  ω6c) and summed feature 8 (comprising C_18 : 1  ω7c and/or C_18 : 1  ω6c) as major fatty acids and ubiquinone-9 as the only respiratory isoprenoid quinone. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid, unidentified phospholipid and unidentified polar lipids were detected as the major polar lipids. Strain TBZ3^T was found to be most closely related to Halomonas saccharevitans AJ275^T , Halomonas denitrificans M29^T and Halomonas sediminicola CPS11^T with the 16S rRNA gene sequence similarities of 98.93, 98.15 and 97.60 % respectively and in phylogenetic analysis strain TBZ3^T grouped with Halomonas saccharevitans AJ275^T contained within a large cluster within the genus Halomonas. Based on phenotypic, chemotaxonomic and molecular properties, strain TBZ3^T represents a novel species of the Halomonas genus, for which the name Halomonas urmiana sp. nov. is proposed. The type strain is TBZ3^T (=DSM 22871^T=LMG 25416^T).

Complete genome sequence of the halophilic PHA-producing bacterium Halomonas sp. SF2003: insights into its biotechnological potential

A halophilic Gram-negative eubacterium was isolated from the Iroise Sea and identified as an efficient producer of polyhydroxyalkanoates (PHA). The strain, designated SF2003, was found to belong to the Halomonas genus on the basis of 16S rRNA gene sequence similarity. Previous biochemical tests indicated that the Halomonas sp. strain SF2003 is capable of supporting various culture conditions which sometimes can be constraining for marine strains. This versatility could be of great interest for biotechnological applications. Therefore, a complete bacterial genome sequencing and de novo assembly were performed using a PacBio RSII sequencer and Hierarchical Genome Assembly Process software in order to predict Halomonas sp. SF2003 metabolisms, and to identify genes involved in PHA production and stress tolerance. This study demonstrates the complete genome sequence of Halomonas sp. SF2003 which contains a circular 4,36 Mbp chromosome, and replaces the strain in a phylogenetic tree. Genes related to PHA metabolism, carbohydrate metabolism, fatty acid metabolism and stress tolerance were identified and a comparison was made with metabolisms of relative species. Genes annotation highlighted the presence of typical genes involved in PHA biosynthesis such as phaA, phaB and phaC and enabled a preliminary analysis of their organization and characteristics. Several genes of carbohydrates and fatty acid metabolisms were also identified which provided helpful insights into both a better knowledge of the intricacies of PHA biosynthetic pathways and of production purposes. Results show the strong versatility of Halomonas sp. SF2003 to adapt to various temperatures and salinity which can subsequently be exploited for industrial applications such as PHA production.

Description of Wenzhouxiangella salilacus sp. nov., a moderate halophilic bacterium isolated from a salt lake in Xinjiang Province, China

A Gram-stain negative, non-motile, strictly aerobic and rod-shaped bacterium, designated as 15181^T, was isolated from a salt lake in Xinjiang Province, China. Strain 15181^T was able to grow at 10-40 °C (optimum 37 °C), pH 6.0-8.5 (optimum 7.0) and with 1-14% NaCl (optimum 4%, w/v). According to phylogenetic analysis based on 16S rRNA gene sequences, strain 15181^T was assigned to the genus Wenzhouxiangella with high 16S rRNA gene sequence similarity of 97.4% to Wenzhouxiangella sediminis XDB06^T, followed by Wenzhouxiangella marina KCTC 42284^T (95.9%). Strain 15181^T exhibited ANI values of 80.0% and 72.0% to W. sediminis XDB06^T and W. marina KCTC 42284^T, respectively. The in silico DDH analysis revealed that strain 15181^T shared 19.1% and 18.7% DNA relatedness with W. sediminis XDB06^T and W. marina KCTC 42284^T, respectively. Chemotaxonomic analysis showed that the sole respiratory quinone was ubiquinone-8, the major fatty acids included iso-C_15:0, iso-C_16:0 and summed feature 9 (C_16:0 10-methyl and/or iso-C_17:1ω9c). The major polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified glycolipids, two unidentified phospholipids, two unidentified aminophospholipids and an unidentified lipid. On the basis of phenotypic, genotypic and chemotaxonomic characteristics presented in this study, strain 15181^T is concluded to represent a novel species in the genus Wenzhouxiangella, for which the name Wenzhouxiangella salilacus sp. nov. is proposed. The type strain is 15181^T (=KCTC 62172^T=MCCC 1K03442^T).

Kordiimonas pumila sp. nov., isolated from coastal sediment

A novel Gram-stain-negative, translucent-white, aerobic, motile and rod-shaped strain, designated N18^T, was isolated from a coastal sediment sample collected in Zhoushan, Zhejiang Province, China. 16S rRNA gene similarity analysis revealed that strain N18^T demonstrated highest similarity to the genus Kordiimonas(95.3-97.2 %). Phylogenetic analysis of 16S rRNA gene sequence showed that strain N18^T represented a distinct lineage in the clade consisting of the genus Kordiimonas. Strain N18^T was found to grow at 10-37 °C (optimum 28 °C), pH 6.0-8.0 (optimum 7.0) and with 1.0-4.0 % (w/v) NaCl (optimum 2.5 %). The G+C content of the genomic DNA was 55.3 mol%. The major cellular fatty acids were identified as summed feature 3 (comprising iso-C15 : 0 2-OH/C16 : 1ω7c), iso-C17 : 1ω9c and iso-C15 : 0. The polar lipid profile of N18^T consisted of phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, an unidentified glycolipid, an unidentified aminoglycolipid, an unidentified aminophospholipid and five unidentified lipids. The respiratory quinone was Q-10. Based on chemotaxonomic, morphological and physiological properties, strain N18^T could be distinguished from its closest phylogenetic neighbours. Thus, we propose Kordiimonas pumila sp. nov., the type strain is N18^T (=MCCC 1K03436^T=KCTC 62164^T).

Genome sequencing and heterologous expression of antiporters reveal alkaline response mechanisms of Halomonas alkalicola

Halomonas alkalicola CICC 11012s is an alkaliphilic and halotolerant bacterium isolated from a soap-making tank (pH > 10) from a household-product plant. This strain can propagate at pH 12.5, which is fatal to most bacteria. Genomic analysis revealed that the genome size was 3,511,738 bp and contained 3295 protein-coding genes, including a complete cell wall and plasma membrane lipid biosynthesis pathway. Furthermore, four putative Na⁺/H⁺ and K⁺/H⁺ antiporter genes, or gene clusters, designated as HaNhaD, HaNhaP, HaMrp and HaPha, were identified within the genome. Heterologous expression of these genes in antiporter-deficient Escherichia coli indicated that HaNhaD, an Na⁺/H⁺ antiporter, played a dominant role in Na⁺ tolerance and pH homeostasis in acidic, neutral and alkaline environments. In addition, HaMrp exhibited Na⁺ tolerance; however, it functioned mainly in alkaline conditions. Both HaNhaP and HaPha were identified as K⁺/H⁺ antiporters that played an important role in high alkalinity and salinity. In summary, genome analysis and heterologous expression experiments demonstrated that a complete set of adaptive strategies have been developed by the double extremophilic strain CICC 11012s in response to alkalinity and salinity. Specifically, four antiporters exhibiting different physiological roles for different situations worked together to support the strain in harsh surroundings.

Aquaticitalea lipolytica gen. nov., sp. nov., isolated from Antarctic seawater

A Gram-stain-negative, rod-shaped bacterium, designated Ar-125^T, was isolated from Antarctic seawater. It produced carotenoid-like pigments and did not produce Bchl a. Ar-125^T was positive for hydrolysis of DNA, aesculin, gelatin, starch, Tween 40 and Tween 60. The sole respiratory quinone was MK-6. The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, one unidentified glycolipid and two unidentified lipids. The principal fatty acids were branched-chain fatty acids, including iso-C15 : 0, iso-C15 : 1 G, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), iso-C16 : 0, iso-C17 : 0 3-OH, iso-C16 : 0 3-OH and iso-C15 : 0 3-OH, as well as C15 : 0. The genomic DNA G+C content was 31.8 mol%. On the basis of 16S rRNA gene sequence analysis, Ar-125^T is closely related to the species of the genera Bizionia(with 16S rRNA gene pairwise sequence similarity of 93.7-96.5 %), Formosa(94.3-95.8 %), Gaetbulibacter(94.2-95.7 %), Geojedonia(95.5 %), Gelidibacter (93.3-95.4 %), Meridianimaribacter(95.3 %) and Psychroserpens (94.8-95.3 %), of the family Flavobacteriaceae. Phylogenetic analysis indicated that it represented an independent lineage and that the closest relatives were members of the genus Gelidibacter. Differential phenotypic properties and chemotaxonomic differences, together with phylogenetic distinctiveness, revealed that Ar-125^T could be differentiated from members of closely related genera. Therefore, it is proposed that Ar-125^T represents a novel species in a new genus, for which the name Aquaticitalea lipolytica gen. nov., sp. nov. (type strain Ar-125^T =CGMCC 1.15295^T =JCM 30876^T) is proposed.

Halomonas aestuarii sp. nov., a moderately halophilic bacterium isolated from a tidal flat

Strain Hb3^T was isolated from a tidal flat in Jeollabuk-do Gunsan, Republic of Korea. Cells were Gram-stain-negative, oxidase- and catalase-positive, rod-shaped and motile. The strain grew optimally at 25-35 °C, at pH 6.0-6.5 and with 3.0-10.0 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain Hb3^T belonged to the genus Halomonas. Strain Hb3^T was related most closely to Halomonas ventosae Al12^T (98.6 % 16S rRNA gene sequence similarity), Halomonas denitrificans M29^T (98.6 %) and Halomonas saccharevitans AJ275^T (98.4 %). Moreover, multilocus sequence analysis using the gyrB, rpoD and secA genes supported the phylogenetic position of strain Hb3^T. The genomic G+C content of strain Hb3^T was 67.9 mol%. DNA-DNA hybridization values for strain Hb3^T versus H. ventosae Al12^T, H. denitrificans M29^T and H. saccharevitans AJ275^T were 38.0, 54.5 and 47.4 %, respectively. The major quinone was ubiquinone Q-9 and the major fatty acids were C18 : 1ω7c, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and C19 : 0 cyclo ω8c. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, amino lipid, six unidentified phospholipids and an unidentified lipid comprised the polar lipid profile. On the basis of the data presented in this report, strain Hb3^T represents a novel species of the genus Halomonas. The name Halomonas aestuarii sp. nov. is proposed for this novel species. The type strain is Hb3^T (=KCTC 52253^T=JCM 31415^T).

Aestuarium zhoushanense gen. nov., sp. nov., Isolated from the Tidal Flat

A gram-stain-negative, aerobic, ovoid or short rod-shaped, and non-motile strain, designed G7^T was isolated from a tidal flat sample collected from the coast of East Sea in Zhoushan, China. Strain G7^T grew at 4-40 °C and pH 6.0-9.0 (optimum, 28 °C and pH 7.5) and with 0-7% (w/v) NaCl (optimum, 1%). The predominant respiratory quinone was Q-10 and the major fatty acids (>10%) identified were C_18:1 ω7c, C_16:0 and summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c). The polar lipids of strain G7^T consisted of phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, and four unidentified lipids. The genomic DNA G+C content was 56.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain G7^T formed a distinct lineage belonging to the Roseobacter clade of the family Rhodobacteraceae. On the basis of morphological, physiological, and chemotaxonomic characteristics, together with the results of phylogenetic analysis, strain G7^T is described as a novel species in a new genus, for which the name Aestuarium zhoushanense gen. nov., sp. nov. (type strain G7^T = MCCC 1K03229^T = KCTC 52584^T) is proposed.

Physiological and genomic features of a novel violacein-producing bacterium isolated from surface seawater

Strains JW1^T and JW3, isolated from surface seawater of the Arabian Sea, were subjected to polyphasic taxonomic analysis. Cells of both strains were Gram-stain-negative, aerobic, and rod-shaped. They formed violet pigment and produced violacein. On the basis of 16S rRNA gene sequence analysis, strains JW1^T and JW3 showed high 16S rRNA gene sequence similarity with Pseudoalteromonas byunsanensis JCM12483^T (98.2%), P. shioyasakiensis SE3^T (97.8%), P. arabiensis JCM 17292^T (97.3%), and P. gelatinilytica NH153^T (97.1%). The 16S rRNA gene sequence similarity between JW1^T and JW3 was 100%. Phylogenetic analyses revealed that both strains fell within the cluster of the genus Pseudoalteromonas and represented an independent lineage. The average nucleotide identity and in silico DNA-DNA hybridization values between JW1^T and type strains of the closely related Pseudoalteromonas species were 70.9–83.3% and 20.0–26.4%, respectively. The sole respiratory quinone in both strains is ubiquinone 8 (Q-8). The principal fatty acids are summed feature 3 (C_16:1ω7c and/or iso-C_15:0 2OH), C_18:1ω7c, and C_16:0. The major polar lipids are phosphatidylethanolamine, phosphatidylglycerol, one unidentified glycolipid, one unidentified aminolipid, and one unidentified phospholipid. The DNA G+C content was 43.3 mol%. Differential phylogenetic distinctiveness, chemotaxonomic differences, and phenotypic properties indicated that strains JW1^T and JW3 could be differentiated from the Pseudoalteromonas species with validly published names. Therefore, it is proposed that strains JW1^T and JW3 represent a novel species of the genus Pseudoalteromonas, for which the name Pseudoalteromonas amylolytica sp. nov. (type strain, JW1^T = CGMCC 1.15681^T = KCTC 52406^T = MCCC 1K02162^T) is proposed.

Chryseobacterium lineare sp. nov., isolated from a limpid stream

A Gram-stain-negative, aerobic, non-motile, rod-shaped, yellow-pigmented bacterial strain, XC0022T, isolated from freshwater of a limpid stream in Zhejiang, China, was studied using a polyphasic approach. The phylogenetic analysis based on 16S rRNA gene sequences clearly showed an allocation to the genus Chryseobacterium with the highest sequence similarities of 98.0 % to Chryseobacterium taeanense PHA3-4T, 97.2 % to Chryseobacterium taihuense THMBM1T, 97.1 % to Chryseobacterium rigui CJ16T and 97.1 % to Chryseobacteriumprofundimaris DY46T. 16S rRNA gene sequence similarities to all other species of the genus Chryseobacterium were below 97.0 % (92.3-96.8 %). DNA-DNA hybridization results showed that strain XC0022T was 55.3 %, 49.8 % and 31.1 % related to C. taeanense DSM 17071T, Chryseobacteriumtaichungense DSM 17453T and Chryseobacteriumgleum JCM 2410T, respectively. The quinone system was composed only of MK-6. Strain XC0022T possessed iso-C15 : 0, iso-C17 : 0 3-OH, C18 : 1ω9c and summed feature 3 (iso-C15 : 0 2-OH/C16 : 1ω7c) as the major fatty acids. The polar lipids profile consisted of one phosphatidylethanolamine, one unidentified glycolipid, four unidentified aminolipids and two unidentified lipids. The G+C content of the genomic DNA was 29.7 mol%. On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain XC0022T (=KCTC 52364T=MCCC 1K02723T) represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium lineare sp. nov. is proposed.

Marinobacterium zhoushanense sp. nov., isolated from surface seawater

A Gram-stain-negative, facultatively anaerobic bacterium, designated WM3T, was isolated from surface seawater collected from the East China Sea. Cells were catalase- and oxidase-positive, short rods and motile by means of a single polar flagellum. Growth occurred at 15-43 °C (optimum 37-40 C), pH 5.5-9.5 (optimum pH 6.5-7.5) and with 0.25-9.0 % (w/v) NaCl (optimum 1.0-1.5 %). Chemotaxonomic analysis showed that the respiratory quinone was ubiquinone-8, the major fatty acids included C16 : 0 (23.6 %), C18 : 1ω7c (26.2 %) and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH, 22.1 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain WM3T was most closely related to the genus Marinobacterium, sharing the highest 16S rRNA gene sequence similarity of 95.5 % with both Marinobacterium litorale KCTC 12756T and Marinobacterium mangrovicola DSM 27697T. The genomic DNA G+C content of the strain WM3T was 55.8 mol%. On the basis of phenotypic, chemotaxonomic and genotypic characteristics presented in this study, strain WM3T is suggested to represent a novel species of the genus Marinobacterium, for which the name Marinobacterium zhoushanense sp. nov. is proposed. The type strain is WM3T (=KCTC 42782T=CGMCC 1.15341T).

Marinirhabdus gelatinilytica gen. nov., sp. nov., isolated from seawater

A Gram-stain-negative, aerobic and slightly halophilic bacterium was isolated from the South China Sea, and was subjected to characterization using a polyphasic taxonomic approach. Cells of the isolate, designated NH83T, were non-motile and rod-shaped. On the basis of 16S rRNA gene sequence analysis, strain NH83Twas closely related to members of the genera Aureisphaera (with sequence similarity of 92.9 %), Jejudonia (92.8 %), Marixanthomonas (92.6 %), Altuibacter (92.6 %), Ulvibacter (91.5-91.9 %), Gilvibacter (91.8 %) and Aequorivita (89.6-91.2 %), all of which belong to the family Flavobacteriaceae. Phylogenetic analysis indicated that it represented an independent lineage and its closest relatives belonged to the genus Marixanthomonas. The sole respiratory quinone was MK-6. The major polar lipids were phosphatidylethanolamine, two aminolipids, one aminophospholipid and one unidentified lipid. The principal fatty acids were branched fatty acids, including iso-C15 : 0, iso-C17 : 0 3-OH, iso-C16 : 0, iso-C15 : 1 G and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c). The genomic DNA G+C content was 41.0 mol%. Strain NH83T was positive for hydrolysis of aesculin, gelatin and Tween 60. Phylogenetic distinctiveness and chemotaxonomic differences, together with differential phenotypic properties, revealed that strain NH83T could be differentiated from closely related genera. Therefore, it is proposed that strain NH83T represents a novel species in a new genus, for which the name Marinirhabdus gelatinilytica gen. nov., sp. nov. (type strain NH83T=CGMCC 1.15462T=DSM 101478T) is proposed.

Isolation and Complete Genome Sequence of Algibacter alginolytica sp. nov., a Novel Seaweed-Degrading Bacteroidetes Bacterium with Diverse Putative Polysaccharide Utilization Loci

The members of the phylum Bacteroidetes are recognized as some of the most important specialists for the degradation of polysaccharides. However, in contrast to research on Bacteroidetes in the human gut, research on polysaccharide degradation by marine Bacteroidetes is still rare. The genus Algibacter belongs to the Flavobacteriaceae family of the Bacteroidetes, and most species in this genus are isolated from or near the habitat of algae, indicating a preference for the complex polysaccharides of algae. In this work, a novel brown-seaweed-degrading strain designated HZ22 was isolated from the surface of a brown seaweed (Laminaria japonica). On the basis of its physiological, chemotaxonomic, and genotypic characteristics, it is proposed that strain HZ22 represents a novel species in the genus Algibacter with the proposed name Algibacter alginolytica sp. nov. The genome of strain HZ22, the type strain of this species, harbors 3,371 coding sequences (CDSs) and 255 carbohydrate-active enzymes (CAZymes), including 104 glycoside hydrolases (GHs) and 18 polysaccharide lyases (PLs); this appears to be the highest proportion of CAZymes (∼7.5%) among the reported strains in the class Flavobacteria Seventeen polysaccharide utilization loci (PUL) are predicted to be specific for marine polysaccharides, especially algal polysaccharides from red, green, and brown seaweeds. In particular, PUL N is predicted to be specific for alginate. Taking these findings together with the results of assays of crude alginate lyases, we prove that strain HZ22(T) can completely degrade alginate. This work reveals that strain HZ22(T) has good potential for the degradation of algal polysaccharides and that the structure and related mechanism of PUL in strain HZ22(T) are worth further research.

Pontibacter amylolyticus sp. nov., isolated from a deep-sea sediment hydrothermal vent field

A Gram-stain-negative, short rod-shaped bacterium, designated 9-2T, was isolated from a sediment sample collected from a hydrothermal vent field on the south-west Indian Ridge. It formed red colonies, produced carotenoid-like pigments and did not produce bacteriochlorophyll a. Strain 9-2T was positive for hydrolysis of DNA, gelatin and starch, but negative for hydrolysis of aesculin and Tween 60. The sole respiratory quinone was menaquinone-7 (MK-7). The main polar lipids consisted of phosphatidylethanolamine, one unidentified phospholipid and two unidentified polar lipids. The principal fatty acids (>5%) were summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B), iso-C15:0 and iso-C17:0 3-OH. The genomic DNA G+C content was 49.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 9-2T should be assigned to the genus Pontibacter. Levels of 16S rRNA gene sequence similarity between the new isolate and the type strains of Pontibacter species with validly published names were in the range 94.0-96.5%. On the basis of phenotypic and genotypic data, strain 9-2T represents a novel species of the genus Pontibacter, for which the name Pontibacter amylolyticus sp. nov. is proposed. The type strain is 9-2T (=CGMCC 1.12749T=JCM 19653T=MCCC 1K00278T).

Brevirhabdus pacifica gen. nov., sp. nov., isolated from deep-sea sediment in a hydrothermal vent field

A Gram-stain-negative, motile, aerobic bacterial strain, designated 22DY15T, was isolated from a deep-sea sediment sample collected from a hydrothermal vent field located in the East Pacific Rise. The isolate was a short rod with a single flagellum and was positive for catalase and oxidase activities. Q-10 was the predominant respiratory quinone. The major polar lipids consisted of phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphoglycolipid, one aminolipid and three unidentified phospholipids. The principal fatty acid (>70 %) was C18 : 1ω7c. The genomic DNA G+C content was 64.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 22DY15T represents a distinct lineage within the family Rhodobacteraceae. The closest relatives were species of the genera Aliiroseovarius (93.3–96.0 % 16S rRNA gene sequence similarity), Sulfitobacter (94.0–96.0 %) and Loktanella (92.0–95.9 %). Differential phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strain 22DY15T could be differentiated from its most closely related genera. Therefore, it is proposed that strain 22DY15T represents a novel species in a new genus of the family Rhodobacteraceae, for which the name Brevirhabdus pacifica gen. nov., sp. nov. is proposed. The type strain of the type species is 22DY15T ( = JCM 19489T = DSM 27767T = CGMCC 1.12416T = MCCC 1K00276T).

Kocuria dechangensis sp. nov., an actinobacterium isolated from saline and alkaline soils

A Gram-stain positive, strictly aerobic, non-motile and coccus-shaped actinobacterium, designated strain NEAU-ST5-33T, was isolated from saline and alkaline soils in Dechang Township, Zhaodong City, PR China. It formed beige-yellow colonies and grew at NaCl concentrations of 0–5 % (w/v) (optimum 0 %), at pH 6.0–9.0 (optimum pH 7.0) and over a temperature range of 4–50 °C (optimum 35 °C). Based on 16S rRNA gene sequence analysis, strain NEAU-ST5-33T was phylogenetically closely related to the type strains of species of the genus Kocuria, Kocuria polaris CMS 76orT, Kocuria rosea DSM 20447T, Kocuria turfanensis HO-9042T, Kocuria aegyptia YIM 70003T, Kocuria himachalensis K07-05T and Kocuria flava HO-9041T, with respective sequence similarities of 98.8 %, 98.8 %, 98.3 %, 98.1 %, 98.1 % and 97.9 %. DNA–DNA hybridization relatedness values of strain NEAU-ST5-33T with type strains of the closely related species ranged from 54 ± 1 % to 34 ± 1 %. The DNA G+C content was 61.2 mol%. The major fatty acids (>5 %) were C15 : 0 anteiso, C15 : 0 iso and C16 : 1ω7c and/or C16 : 1ω6c. The major menaquinone detected was MK-8 (H2), and the polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unknown aminolipid and one unknown lipid. On the basis of the genotypic, chemotaxonomic and phenotypic data, we propose that strain NEAU-ST5-33T represents a novel species of the genus Kocuria, with the name Kocuria dechangensis sp. nov. The type strain is NEAU-ST5-33T ( = CGMCC 1.12187T = DSM 25872T).

Pseudoroseovarius zhejiangensis gen. nov., sp. nov., a novel alpha-proteobacterium isolated from the chemical wastewater, and reclassification of Roseovarius crassostreae as Pseudoroseovarius crassostreae comb. nov., Roseovarius sediminilitoris as Pseudoroseovarius sediminilitoris comb. nov. and Roseovarius halocynthiae as Pseudoroseovarius halocynthiae comb. nov

A Gram-stain negative, aerobic, non-motile and ovoid- to rod-shaped bacterial strain, designated JB3(T), was isolated from a wastewater sample collected from the biochemical reaction basin of Haiyan fine chemical factory in Zhejiang, China. Strain JB3(T) was found to grow optimally at pH 7.0-8.0, at 28 °C and in the presence of 1.0-2.0 % (w/v) NaCl. Chemotaxonomic analysis showed that strain JB3(T) contains ubiquinone-10 (>99 %) as the predominant respiratory quinone and C18:1 ω7c (70.9 %) as the most abundant fatty acid. The polar lipids of strain JB3(T) were identified as phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an aminophospholipid, an unidentified aminolipid, four unidentified phospholipids and three unidentified lipids. The DNA G+C content of strain JB3(T) was determined to be 68.1 mol%. The 16S rRNA gene sequence similarities between the isolate and Roseovarius crassostreae DSM 16950(T), Roseovarius sediminilitoris KCTC 23959(T) and Roseovarius halocynthiae MA1-10(T) were found to be 97.1, 96.8 and 96.2 %, respectively. Morevoer, the similarity between strain JB3(T) and the type strain of the genus Roseovarius (Roseovarius tolerans DSM 11457(T)) was found to be 93.8 %. The phylogenetic trees reconstructed with all three treeing methods showed that strain JB3(T) constituted a different taxon, which was separate from other taxa with validly published names, and formed a cluster with R. crassostreae DSM 16950(T), R. sediminilitoris KCTC 23959(T) and R. halocynthiae MA1-10(T). These three species were not placed within the phylogenetic cluster formed by R. tolerans DSM 11457(T). Differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain JB3(T) is clearly distinct from species of the genus Roseovarius. On the basis of these features, we propose strain JB3(T) represents a novel species of a novel genus with the name Pseudoroseovarius zhejiangensis gen. nov., sp. nov. The type strain is JB3(T) (=MCCC 1K00457(T) = KCTC 42443(T)). We also propose that R. crassostreae, R. sediminilitoris and R. halocynthiae should be transferred to this new genus as Pseudoroseovarius crassostreae comb. nov., Pseudoroseovarius sediminilitoris comb. nov. and Pseudoroseovarius halocynthiae comb. nov., respectively.

Halobacillus andaensis sp. nov., a moderately halophilic bacterium isolated from saline and alkaline soil

A Gram-stain-positive, endospore-forming, moderately halophilic bacterial strain, NEAU-ST10-40T, was isolated from a saline and alkaline soil in Anda City, China. It was strictly aerobic, rod-shaped and motile by peritrichous flagella. It formed light yellow colonies and grew at NaCl concentrations of 3–15 % (w/v) (optimum, 8 %, w/v), at pH 7.0–9.0 (optimum, pH 8.0) and at 4–60 °C (optimum, 30 °C). It contained meso-diaminopimelic acid in the cell-wall peptidoglycan. Phylogenetic analysis based on 16S rRNA gene sequences indicated that it belonged to the genus Halobacillus. Levels of 16S rRNA gene sequence similarity between strain NEAU-ST10-40T and the type strains of related species of the genus Halobacillus ranged from 98.8 % (Halobacillus alkaliphilus FP5T) to 97.1 % (Halobacillus kuroshimensis IS-Hb7T). DNA–DNA hybridization relatedness values between strain NEAU-ST10-40T and H. alkaliphilus DSM 18525T, Halobacillus campisalis KCTC 13144T, Halobacillus yeomjeoni DSM 17110T, Halobacillus halophilus DSM 2266T, Halobacillus litoralis DSM 10405T, Halobacillus dabanensis DSM 18199T, Halobacillus salinus DSM 18897T, Halobacillus naozhouensis DSM 21183T, Halobacillus trueperi DSM 10404T and Halobacillus salsuginis DSM 21185T were from 43 ± 1 to 19 ± 1 % (mean ± sd). The DNA G+C content was 39.3 mol%. The major fatty acids (>10 %) were anteiso-C15:0, anteiso-C17:0 and iso-C16:0, the only respiratory quinone detected was MK-7, and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unknown phospholipids and three unknown lipids. On the basis of the data presented, strain NEAU-ST10-40T is considered to represent a novel species, for which the name Halobacillus andaensis sp. nov. is proposed. The type strain is NEAU-ST10-40T ( = CGMCC 1.12153T = DSM 25866T).

Planococcus dechangensis sp. nov., a moderately halophilic bacterium isolated from saline and alkaline soils in Dechang Township, Zhaodong City, China

Strain NEAU-ST10-9(T) is a moderately halophilic, coccoid and non-motile bacterium isolated from saline and alkaline soils in the Dechang Township, Zhaodong City, China. The bacterium was found to be aerobic and Gram-stain positive. It forms orange colonies and grows at NaCl concentrations of 2-10 % (w/v) (optimum, 4 % w/v), at 4-50 °C (optimum, 30 °C) and at pH 6.0-10.0 (optimum, pH 7.0). Phylogenetic analyses based on 16S rRNA gene sequences indicated that it belongs to the genus Planococcus within the family Planococcaceae. The most closely related species was Planococcus maritimus, whose type strain (TF-9(T)) showed gene sequence similarities of 99.1 % for 16S rRNA, 83.7 % for gyrB and 87.0 % for rpoB with those of strain NEAU-ST10-9(T), respectively. DNA-DNA hybridization relatedness values between strain NEAU-ST10-9(T) and type strains P. maritimus DSM 17275(T) , P. rifietoensis DSM 15069(T) , P. plakortidis DSM 23997(T), P. citreus DSM 20549(T), P. maitriensis DSM 15305(T), P. salinarum KCTC 13584(T) and P. columbae DSM 17517(T) were from 55 ± 1 to 32 ± 2 %. The DNA G+C content was found to be 45.2 mol %. The major fatty acids (>5 %) were determined as C15:0 anteiso, C16:1 ω7c alcohol, C17:1 ω9c and C17:0 anteiso. The major menaquinones of strain NEAU-ST10-9(T) were identified as MK-7 and MK-8. The polar lipids were found to contain of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphocholine and two unknown lipids. The genotypic, chemotaxonomic and phenotypic analysis indicated that strain NEAU-ST10-9(T) represents a novel species of the genus Planococcus, for which we proposed the name Planococcus dechangensis sp. nov. The type strain is NEAU-ST10-9(T) (=CGMCC 1.12151(T)=DSM 25871(T)).

Novosphingobium marinum sp. nov., isolated from seawater

A Gram-stain-negative, aerobic, short rod-shaped bacterium, strain LA53T, was isolated from a deep-sea water sample collected from the eastern Pacific Ocean. Strain LA53T grew in the presence of 0–7.0 % (w/v) NaCl and at 15-37 °C; optimum growth was observed with 1.0–2.0 % (w/v) NaCl and at 35 °C. Chemotaxonomic analysis showed ubiquinone-10 as the predominant respiratory quinone, C18 : 1ω7c and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c) as major fatty acids, and diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid as major polar lipids. The genomic DNA G+C content was 57.7 mol%. Phylogenetic analyses revealed that strain LA53T belongs to the genus Novosphingobium . 16S rRNA gene sequence similarities between strain LA53T and the type strains of species of the genus Novosphingobium with validly published names ranged from 93.1 to 96.3 %. In addition, strain LA53T could be differentiated from Novosphingobium pentaromativorans DSM 17173T and Novosphingobium indicum DSM 23608T as well as the type strain of the type species of the genus, Novosphingobium capsulatum DSM 30196T, by some phenotypic characteristics, including hydrolysis of substrates, utilization of carbon sources and susceptibility to antibiotics. On the basis of phenotypic and genotypic data, strain LA53T represents a novel species within the genus Novosphingobium , for which the name Novosphingobium marinum sp. nov. is proposed. The type strain is LA53T ( = CGMCC 1.12918T = JCM 30307T).