Yanghanlia caeni gen. nov., sp. nov., a novel taxon within the family Alcaligenaceae isolated from sludge of a pesticide-manufacturing factory

A Gram-stain-negative bacterium, designated LG-2T, was isolated from sludge collected at a pesticide-manufacturing factory in Jiangsu Province, PR China. Cells of strain LG-2T were strictly aerobic, non-motile and spherical. Growth was observed at 15-42 °C (optimum, 30 °C), pH 6.0-9.0 (optimum, pH 7.0) and 0-3.0 % (w/v) NaCl (optimum, 1.0 %). LG-2T showed 95.5-96.9 % 16S rRNA sequence similarity to type strains in the genera Pusillimonas, Bordetella, Parapusillimonas, Candidimonas and Paracandidimonas of the family Alcaligenaceae. The phylogenomic tree indicated that strain LG-2T was clustered in the family Alcaligenaceae and formed a clade with Paracandidimonas soli IMT-305T, while the phylogenetic trees based on 16S rRNA gene sequences indicated that strain LG-2T formed a distinct clade within the family Alcaligenaceae. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between LG-2T and its closely related type strains in the genera Pusillimonas, Bordetella, Parapusillimonas, Candidimonas and Paracandidimonas were 70.8-75.3, 18.9-23.7 and 59.6 %-69.3 %, respectively. The major cellular fatty acids were C16 : 0, C17 : 0 cyclo, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and summed feature 2 (C12 : 0 aldehyde and/or unknown 10.928). The predominant menaquinone was Q-8. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, two aminophospholipids, three aminolipids and nine unknown polar lipids. The genome size of strain LG-2T was 3.2 Mb and the DNA G+C content was 63.4 mol%. On the basis of the phenotypic, phylogenetic and genomic results from this study, strain LG-2T represents a novel species of a new genus in the family Alcaligenaceae, for which the name Yanghanlia caeni gen. nov., sp. nov. is proposed, with strain LG-2T (=KCTC 8084T= CCTCC AB 2023123T) as the type strain.

Gracilibacillus salinarum sp. nov. and Gracilibacillus caseinilyticus sp. nov., halotolerant bacteria isolated from a saltern environment

Two aerobic, Gram-stain-positive, spore-forming motile bacterial strains, designated SSPM10-3T and SSWR10-1T, were isolated from salterns in Jeollanam province of South Korea. Both strains were halotolerant and grew well in 5 % NaCl but not in 20 and 25% NaCl, respectively. Optimal growth was observed with 5 % NaCl, at 30 °C and at pH 7.0-8.0. On the basis of the results of phylogenetic analysis using 16S rRNA gene sequence, both the strains were placed within the genus Gracilibacillus with Gracilibacillus massiliensis (98.65 % similarity) as their nearest neighbour. Menaquinone-7 (MK-7) (97 %) was the major isoprenoid quinone in both strains and major cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0 and anteiso-C17 : 0. Orthologous average nucleotide identity with usearch (OrthoANIu) and digital DNA-DNA hybridisation (dDDH) percentage comparison indicated that SSPM10-3T and SSWR10-1T exhibited highest similarity with G. massiliensis Awa-1T at 74.27 % and 21.0 and 74.23 % and 20.0 %, respectively. The DNA G+C contents of the strains were 39.1 % (SSPM10-3T) and 38.5 % (SSWR10-1T). Members of the genus Gracilibacillus, both strains were distinct from each other with respect to their ability to produce urease, β-glucosidase, assimilation of inulin and methyl-α-d-glucopyranoside and degradation of casein. Compared with each other, ANI and d4 dDDH calculations were only 88.2 % and 36.3 %, well below the cut-off values for species delineation for each index. On the basis of their phenotypic, physiological, biochemical and phylogenetic characteristics,SSPM10-3T and SSWR10-1T represent distinct novel species for which names Gracilibacillus salinarum SSPM10-3T and Gracilibacillus caseinilyticus SSWR10-1T are proposed. The type strains are SSPM10-3T (=KACC 21933T =NBRC 115502T) and SSWR10-1T (=KACC 21934T =NBRC 115503T).

A culture-based and culture-independent approach to the study of landfill leachate bacterial and archaeal communities

The landfill is a convenient and affordable method of municipal solid waste (MSW) management. Landfill leachate contains a heavy load of pollutants and pathogens. Discharge of untreated leachate is the leading cause of surface and groundwater contamination and a threat to public and environmental health. To develop an efficient leachate treatment technology, an in-depth understanding of landfill chemistry and microbiology is essential. In the present manuscript, we conducted a comparative study of three different landfill leachate samples using cultivation-based and culture-independent molecular studies. We cultivated 85 species of aerobic, anaerobic bacteria and archaea from leachate represented by a total of 200 strains using extensive culturomics approaches. Twelve out of 200 cultivated strains of bacteria showed very low 16S rRNA gene sequence similarity (84-98.6%) with their closest relatives and could be the potential novel taxa, the first time cultivated from leachate. Members of the six genera only have 2-5 representatives from past studies from other habitats but first time cultivated from leachate. In addition to bacteria, we also cultivated and characterized different groups of methanogenic archaea. Our chemistry data indicate that leachate is a highly stressed ecosystem with an assemblage of many toxic wastes like sulfur, zinc, mercury, chromium, etc. 16S rRNA gene-based amplicon analysis showed the dominance of (30-55%) methanogens and haloarachaea. Our data suggest that archaea are the significant regulators of leachate ecology, and more in-depth studies with multiple leachate samples are required to understand their role in leachate nutrient cycling and the development of effective leachate treatment technology.

Leucobacter chinensis sp. nov., with plant growth-promoting potential isolated from field soil after seven-years continuous maize cropping

A novel Gram-stain-positive, aerobic, non-motile and rod-shaped bacterium, designated strain NC76-1^T, was isolated from soil from a field that had undergone seven years continuous maize cropping from Liuba town located in Zhangye city, Gansu province, PR China. Colonies of strain NC76-1^T were white, opaque and circular with a convex shape. The isolate was found to be able to grow at 10-40 °C (optimum 30 °C), pH 6.0 to 12.0 (optimum 7.0-8.0) and with 0-5.0 % (w/v) NaCl (optimum 0%). On the basis of the results of 16S rRNA gene sequence analysis, the strain fell within the clade of the genus Leucobacter, showing the highest sequence similarities with Leucobacter iarius 40^T (97.4%), Leucobacter aridicollis CIP 108388^T (97.0%), Leucobacter chromiireducens subsp. solipictus TAN 31504^T (96.7%) and Leucobacter denitrificans M1T8B10^T (96.7%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between NC76-1^T and its closest relatives, L. iarius 40^T, L. aridicollis CIP 108388^T, L. chromiireducens subsp. solipictus TAN 31504^T and L. denitrificans M1T8B10^T were ≤73.5 % and 20.3%, respectively. The genomic DNA G+C content of NC76-1^T was 61.5 mol%. It presented MK-11 as the predominant menaquinone. The major cellular fatty acids were anteiso-C_15 : 0 (49.2 %) and iso-C_16 : 0 (35.7%). The major polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, aminoglycolipid, five glycolipid and one unidentified lipids. The cell wall amino acids were 2,4-diaminobutyric acid, alanine, glutamic acid, glycine and threonine. On the basis of the phylogenetic, phenotypic and chemotaxonomic characteristics, strain NC76-1^T is concluded to represent a novel species within the genus Leucobacter, for which the name Leucobacter chinensis sp. nov. is proposed. The type strain is NC76-1^T (GDMCC 1.2286^T= JCM 34651^T).

Gracilibacillus suaedae sp. nov., an indole acetic acid-producing endophyte isolated from a root of Suaeda salsa

A Gram-stain-positive, facultatively anaerobic, spore-forming, motile with unipolar biflagella, rod-shaped, indole acetic acid-producing bacterium, named LD4P30^T, was isolated from a root of Suaeda salsa collected in Inner Mongolia, northern China. Strain LD4P30^T grew at pH 6.0-11.0 (optimum, pH 7.0), 10-40 °C (35 °C) and in the presence of 1-15% (w/v) NaCl (5%). The strain was positive for oxidase and negative for catalase. The major cellular fatty acids of strain LD4P30^T were iso-C_15:0, C_15:1 ω5c and anteiso-C_15:0; the major polar lipids were diphosphatidylglycerol and phosphatidylglycerol; and menaquinone-7 was the only respiratory quinone. The genomic DNA G+C content was 36.7 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain LD4P30^T clustered with Gracilibacillus thailandensis TP2-8^T, Gracilibacillus saliphilus YIM 91119^T and Gracilibacillus lacisalsi BH312^T, and showed 99.0, 98.9, 98.0 and <97.7% 16S rRNA gene similarity to G. thailandensis TP2-8^T, G. saliphilus YIM 91119^T, G. lacisalsi BH312^T and all other current type strains, respectively. The digital DNA-DNA hybridization and average nucleotide identity based on blast values between strain LD4P30^T and G. saliphilus YIM 91119^T, G. thailandensis TP2-8^T and G. lacisalsi BH312^T were 44.9, 44.7 and 44.4%, and 91.1, 91.0 and 90.8%, respectively. Based on its phenotypic, physiological and phylogenetic characteristics, strain LD4P30^T represents a novel species, for which the name Gracilibacillus suaedae is proposed. The type strain is LD4P30^T (=CGMCC 1.17697^T=KCTC 82375^T).

Characterization of β-galactosidase and α-galactosidase activities from the halophilic bacterium Gracilibacillus dipsosauri

Purpose

Gracilibacillus dipsosauri strain DD1 is a salt-tolerant Gram-positive bacterium that can hydrolyze the synthetic substrates o-nitrophenyl-β-d-galactopyranoside (β-ONP-galactose) and p-nitrophenyl-α-d-galactopyranoside (α-PNP-galactose). The goals of this project were to characterize the enzymes responsible for these activities and to identify the genes encoding them.

Methods

G. dipsosauri strain DD1 was grown in tryptic soy broth containing various carbohydrates at 37 °C with aeration. Enzyme activities in cell extracts and whole cells were measured colorimetrically by hydrolysis of synthetic substrates containing nitrophenyl moieties. Two enzymes with β-galactosidase activity and one with α-galactosidase activity were partially purified by ammonium sulfate fractionation, ion-exchange chromatography, and gel-filtration chromatography from G. dipsosauri. Coomassie Blue-stained bands corresponding to each activity were excised from nondenaturing polyacrylamide gels and subjected to peptide sequencing after trypsin digestion and HPLC/MS analysis.

Result

Formation of β-galactosidase and α-galactosidase activities was repressed by d-glucose and not induced by lactose or d-melibiose. β-Galactosidase I had hydrolytic and transgalactosylation activity with lactose as the substrate but β-galactosidase II showed no activity towards lactose. The α-galactosidase had hydrolytic and transgalactosylation activity with d-melibiose but not with d-raffinose. β-Galactosidase I had a lower Km with β-ONP-galactose as the substrate (0.693 mmol l−1) than β-galactosidase II (1.662 mmol l−1), was active at more alkaline pH, and was inhibited by the product d-galactose. β-Galactosidase II was active at more acidic pH, was partially inhibited by ammonium salts, and showed higher activity with α-PNP-arabinose as a substrate. The α-galactosidase had a low Km with α-PNP-galactose as the substrate (0.338 mmol l−1), a pH optimum of about 7, and was inhibited by chloride-containing salts. β-Galactosidase I activity was found to be due to the protein A0A317L6F0 (encoded by gene DLJ74_04930), β-galactosidase II activity to the protein A0A317KZG3 (encoded by gene DLJ74_12640), and the α-galactosidase activity to the protein A0A317KU47 (encoded by gene DLJ74_17745).

Conclusions

G. dipsosauri forms three intracellular enzymes with different physiological properties which are responsible for the hydrolysis of β-ONP-galactose and α-PNP-galactose. BLAST analysis indicated that similar β-galactosidases may be formed by G. ureilyticus, G. orientalis, and G. kekensis and similar α-galactosidases by these bacteria and G. halophilus.

Rhodobacter kunshanensis sp. nov., a Novel Bacterium Isolated from Activated Sludge

Strain HX-7-19^T was isolated from the activated sludge collected from an abandoned herbicide manufacturing plant in Kunshan, China. Cells were Gram-reaction-negative, rod-shaped, and non-motile. The phylogenetic analysis based on 16S rRNA gene indicated that strain HX-7-19^T formed a clade with Rhodobacter blasticus CGMCC 1.3365^T (96.3% sequence similarity). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain HX-7-19^T and R. blasticus CGMCC 1.3365^T were 76.2% and 20.3%, respectively. The genomic DNA G + C content of strain HX-7-19^T was 65.9%. The major fatty acids (> 10% of the total fatty acids) were C_18:1 ω7c and C_18:1 ω7c 11-methyl. The major respiratory quinone was quinone Q-10. The major polar lipid profile consists of phosphatidylglycerol (PG), diphosphatidyl-glycerol (DPG), phosphatidylethanolamine (PE), and phosphatidylcholine (PC). Photosynthesis pigments bacteriochlorophyll a and carotenoids were formed and photosynthesis genes pufL and pufM were detected. On the basis of phenotypic and phylogenetic evidences, strain HX-7-19^T is considered as a novel species in the genus Rhodobacter, for which the name Rhodobacter kunshanensis sp. nov. is proposed. The type strain is HX-7-19^T (= KCTC 72471^T = CCTCC AB 2020148^T).

Description of Gracilibacillus phocaeensis sp. nov., a new halophilic bacterium isolated from Senegalian human stool

Using the taxonogenomics method, we describe Gracilibacillus phocaeensis strain Marseille-P3801, a new species previously isolated from a salty stool of a 20-year-old man from N'Diop, Senegal. It is a Gram-positive, aerobic and motile bacillus. The major fatty acids are C15:0-anteiso (59%), C16:0 (16%) and C17:0-anteiso (11%). Strain Marseille-P3801 exhibits a 98.45% sequence similarity with Gracilibacillus thailandensis strain TP2-8, the phylogenetically closest species. Its genome is 4.66 Mb with 39.6 mol% G + C content.

Gracilibacillus oryzae sp. nov., isolated from rice seeds

A Gram-stain-positive, facultatively anaerobic, endospore-forming bacterium, designated strain TD8^T, was isolated from surface-sterilized rice seeds (Oryza sativa L.). Phylogenetic analysis of the 16S rRNA gene indicated that strain TD8^T should be placed within the genus Gracilibacillus (95.2-99.0 % sequence similarity); it exhibited highest similarities to Gracilibacillus ureilyticus CGMCC 1.7727^T (99.0 %), 'Gracilibacillus xinjiangensis' CGMCC 1.12449^T (98.9 %) and Gracilibacillus dipsosauri CGMCC 1.3642^T (97.5 %). Chemotaxonomic analysis showed that menaquinone-7 (MK-7) was the major isoprenoid quinone. Diphosphatidylglycerol, phosphatidylglycerol and one unidentified phospholipid were the major cellular polar lipids, and the major fatty acids were anteiso-C_15 : 0, anteiso-C_17 : 0, iso-C_15 : 0, C_16 : 0 and iso-C_16 : 0, which supported the allocation of the strain to the genus Gracilibacillus. The digital DNA-DNA hybridization value between strain TD8^T and Gracilibacillus ureilyticus CGMCC 1.7727^T was lower than 70 % (22.60 %), and the average nucleotide identity score was 79.54±5.09 %, suggesting that strain TD8^T represented a novel species in the genus Gracilibacillus. The genomic DNA G+C content was 37.5 %. Based on physiological and biochemical characteristics and genotypic data, strain TD8^T represents a novel species of the genus Gracilibacillus, for which the name Gracilibacillus oryzae sp. nov. is proposed. The type strain is TD8^T (=ACCC 61556^T=CICC 24889^T=JCM 33537^T).

Gracilibacillus salitolerans sp. nov., a moderate halophile isolated from saline soil in Northwest China

A moderately halophilic strain, designated SCU50T, was recovered from a saline soil sample and characterized by a polyphasic approach. The 16S rRNA gene sequence analysis showed that strain SCU50T belonged to the genus Gracilibacillus and was most closely related to Gracilibacillus thailandensis TP2-8T (98.1 % similarity) and Gracilibacillus orientalis XH-63T (97.7 %). Genomic average nucleotide identity and digital DNA–DNA hybridization analyses confirmed the separate species status of the new isolate relative to other recognized Gracilibacillus species. The genome size was about 5.09 Mbp and the DNA G+C content was 36.7 mol%. The strain grew optimally at 10–15 % (w/v) NaCl, pH 6.5–7.5 and 25–30 °C. It contained anteiso-C15 : 0, iso-C15 : 0 and anteiso-C17 : 0 as the dominant fatty acids and menaquinone-7 as the major respiratory quinone. The polar lipid profile was examined and found to comprise diphosphatidylglycerol, phosphatidylglycerol, one unidentified phospholipid and one unidentified lipid. The cell-wall peptidoglycan type was A1γ based on meso-diaminopimelic acid. Combining the data from phenotypic, chemotaxonomic, genomic and phylogenetic characterization, it was concluded that strain SCU50T should be assigned as representing a novel species within the genus Gracilibacillus . Thus, a novel taxon named Gracilibacillus salitolerans sp. nov. was first established, with SCU50T (=CGMCC 1.17336T=KCTC 43107T) as the type strain.

Genomic sequencing of Gracilibacillus dipsosauri reveals key properties of a salt-tolerant α-amylase

Gracilibacillus dipsosauri is a moderately-halophilic Gram-positive bacterium which forms an extracellular α-amylase that is induced by starch, repressed by D-glucose, and active in 2.0 M KCl. Previous studies showed that while enzyme activity could be measured with the synthetic substrate 2-chloro-4-nitrophenyl-α-D-maltotrioside (CNPG3), other assays were inconsistent and the protein showed aberrant mobility during nondenaturing gel electrophoresis. To clarify the properties of this enzyme, the genome of G. dipsosauri was sequenced and was found to be 4.19 Mb in size with an overall G+C content of 36.9%. A gene encoding an α-amylase composed of 691 amino acids was identified. The protein was a member of the glycosyl hydrolase 13 family, which had a molecular mass of 77,396 daltons and a pI of 4.39 due to an unusually large number of aspartate and glutamate residues (95/691 or 13.7%). BLAST analysis of the amino acid sequence revealed significant matches to other proteins with cyclodextrin glycosyltransferase activity. Partial purification of the protein from G. dipsosauri showed that fractions catalyzing the hydrolysis of CNPG3 and p-nitrophenyl-D-maltoheptoside also catalyzed the formation of β-cyclodextrin but not α-cyclodextrin or γ-cyclodextrin. Formation of β-cyclodextrin was not stimulated by high salt concentrations but did occur with rice, potato, wheat, and corn starches and amylopectin. These studies explain the unusual features of the α-amylase from G. dipsosauri and indicate it should be classified as EC 2.4.1.19. The availability of the complete genomic sequence of G. dipsosauri will provide the basis for studies on other enzymes from this halophile which may be useful for biotechnology.

Extensimonas perlucida sp. nov., a Novel Bacterium Isolated from Sludge

A bacterium, designated HX2-24 ^T, was isolated from activated sludge treating pesticide-manufacturing wastewater. Colonies of the strain on nutrient agar were circular, transparent, and colorless. Strain HX2-24 ^T shared 98.1% 16S rRNA gene sequence similarity with Extensimonas vulgaris S4^T, and less than 97% similarities with other type strains. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain formed a clade with E. vulgaris S4^T. The major cellular fatty acids were C_16:0, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c) and C_17:0 cyclo, the major polar lipids were phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), aminophospholipid (APL), glycophospholipid (GPL), and aminoglycolipid (AGL). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between HX2-24 ^T and E. vulgaris S4^T were 92% and 41%, respectively. The G + C content of strain HX2-24 ^T was 64.4 mol%. Thus, based on the phenotypic, chemotaxonomic, and genotypic characteristics, strain HX2-24 ^T represents a novel species in the genus Extensimonas, for which the name Extensimonas perlucida HX2-24 ^T sp. nov. is proposed. The type strain is HX2-24 ^T (= KCTC 72472 ^T = CCTCC AB 2019178 ^T).

Anaerophilus nitritogenes gen. nov., sp. nov., isolated from salt lake sediment in Xinjiang Province, China

An obligately anaerobic, nitrate-reducing bacterial strain (MJB2^T) was isolated from sediments of saline in Xinjiang province of China. Cells were Gram-stain-positive rods and motile by means of flagella and formed endospores. The novel strain MJB2^T was able to grow at 15-37 °C (optimum 28-30 °C), pH 5.8-9.4 (optimum 7.8) and with 1.0-7.0% NaCl (optimum 5.0-6.0%, w/v). Sulfate, sulfite, thiosulfate, elemental sulfur, nitrite and Fe(III) were not used as terminal electron acceptors. Oxidase and catalase reactions were positive. H₂S was producted from L-cystine. Complex substrates such as beef extract, peptone and yeast extract can be used as sole energy sources. The DNA G+C content was 29.4 mol%. The major cellular fatty acids (> 10%) were C_14:0, C_16:1 cis 7 and C_16:1 cis 9. The main polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, three unidentified amino lipids, one unidentified amino glycolipid, two unidentified glycolipid, one unidentified aminophospholipid and two unidentified lipids. No respiratory quinones were detected. According to phylogenetic analysis based on 16S rRNA gene sequences, strain MJB2^T was affiliated to the family Clostridiaceae (order Clostridiales) with highest 16S rRNA gene sequence similarity of 95.3% to Crassaminicella profunda Ra1766H^T. Strain MJB2^T exhibited 74.9% ANI values to C. profunda Ra1766H^T. In silico DNA-DNA relatedness value between strain MJB2^T and C. profunda Ra1766H^T was 19.5%. The distinct biochemical, chemotaxonomic and phylogenetic differences from the previously described taxa supported that strain MJB2^T represents a novel species of a new genus, for which the name Anaerophilus nitritogenes gen. nov., sp. nov. is proposed. The type strain is MJB2^T (=KCTC 15800^T=MCCC 1K03631^T).

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).

Genome sequence and description of Gracilibacillus timonensis sp. nov. strain Marseille-P2481T , a moderate halophilic bacterium isolated from the human gut microflora

Microbial culturomics represents an ongoing revolution in the characterization of the human gut microbiota. By using three culture media containing high salt concentrations (10, 15, and 20% [w/v] NaCl), we attempted an exhaustive exploration of the halophilic microbial diversity of the human gut and isolated strain Marseille‐P2481 (= CSUR P2481 =  DSM 103076), a new moderately halophilic bacterium. This bacterium is a Gram‐positive, strictly aerobic, spore‐forming rod that is motile by use of a flagellum and exhibits catalase, but not oxidase activity. Strain Marseille‐P2481 was cultivated in media containing up to 20% (w/v) NaCl, with optimal growth being obtained at 37°C, pH 7.0–8.0, and 7.5% [w/v] NaCl). The major fatty acids were 12‐methyl‐tetradecanoic acid and hexadecanoic acid. Its draft genome is 4,548,390 bp long, composed of 11 scaffolds, with a G+C content of 39.8%. It contains 4,335 predicted genes (4,266 protein coding including 89 pseudogenes and 69 RNA genes). Strain Marseille‐P2481 showed 96.57% 16S rRNA sequence similarity with Gracilibacillus alcaliphilus strain SG103^T, the phylogenetically closest species with standing in nomenclature. On the basis of its specific features, strain Marseille‐P2481^T was classified as type strain of a new species within the genus Gracilibacillus for which the name Gracilibacillus timonensis sp. nov. is formally proposed.

Altererythrobacter xixiisoli sp. nov., isolated from wetland soil

A Gram-stain-negative, coccoid, yellow, non-motile, aerobic bacterium, designated strain S36T, was isolated from soil of the Xixi wetland in Zhejiang province, PR China. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain S36T could represent a novel species of genus Altererythrobacter showing highest similarity to Altererythrobacter atlanticus 26DY36T (96.31 % 16S rRNA gene sequence similarity). The temperature, pH and NaCl concentration ranges for growth were 10-37 °C (optimum 32 °C), pH 5.0-10.0 (optimum pH 7.0) and 0.5-3 % (optimum 1 %, w/v), respectively. The predominant respiratory quinone of strain S36T was Q-10. The major fatty acids were C16 : 0, C17 : 1ω6c, C18 : 1ω7c and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH). The G+C content of the genomic DNA was 62.7 mol%. These data all support the affiliation of strain S36T to the genus Altererythrobacter. The polar lipids profile of strain S36T comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified phospholipids and two unidentified glycolipids. The results of physiological and biochemical tests allowed differentiation of strain S36T from other members of the genus Altererythrobacter. Therefore, strain S36T represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter xixiisoli sp. nov. is proposed; the type strain is S36T (=CGMCC 1.12804T=NBRC 110413T).

Gracilibacillus aidingensis sp. nov., a novel moderately halophilic bacterium isolated from Aiding salt lake

A novel Gram-positive, aerobe, moderately halophilic bacterium was isolated from saline soil of Aiding lake in Xinjiang, north-west of China, designated strain YIM 98001^T. Cells were rod-shaped, motile and grew at 5-20% (w/v) NaCl (optimum 10%), pH 6-10 (optimum pH 7.0) and 4-45 °C (optimum 37 °C). The major cellular fatty acids were anteiso C_15:0, anteiso C_17:0, iso C_15:0. The predominant respiratory quinone was MK-7. Diphosphatidylglycerol, phosphatidylglycerol, phosphoglycolipid were the major polar lipids. Meso-diaminopimelic acid was the diagnostic diamino acid of the cell-wall peptidoglycan. The G+C content was 36.46 mol%. 16S rRNA gene sequence analysis showed that the strain belongs to the family Bacillaceae, with the highest sequence similarity to the type strain Gracilibacillus thailandensis TP2-8^T (96.84%), followed by Gracilibacillus saliphilus YIM 91119^T (96.78%) and Gracilibacillus ureilyticus MF38^T (96.57%), thus confirming the affiliation of strain YIM 98001^T to the genus Gracilibacillus. The polyphasic approach indicates that strain YIM 98001^T represents a novel species of the genus Gracilibacillus, for which the name Gracilibacillus aidingensis is proposed. The type strain is YIM 98001^T (=KCTC 42683^T = DSMZ 104330^T).

Microbial culturomics unravels the halophilic microbiota repertoire of table salt: description of Gracilibacillus massiliensis sp. nov

Background

Microbial culturomics represents an ongoing revolution in the characterization of environmental and human microbiome.

Methods

By using three media containing high salt concentration (100, 150, and 200 g/L), the halophilic microbial culturome of a commercial table salt was determined.

Results

Eighteen species belonging to the Terrabacteria group were isolated including eight moderate halophilic and 10 halotolerant bacteria. Gracilibacillus massiliensis sp. nov., type strain Awa-1^T (=CSUR P1441=DSM 29726), is a moderately halophilic gram-positive, non-spore-forming rod, and is motile by using a flagellum. Strain Awa-1^T shows catalase activity but no oxidase activity. It is not only an aerobic bacterium but also able to grow in anaerobic and microaerophilic atmospheres. The draft genome of G. massiliensis is 4,207,226 bp long, composed of 13 scaffolds with 36.05% of G+C content. It contains 3,908 genes (3,839 protein-coding and 69 RNA genes). At least 1,983 (52%) orthologous proteins were not shared with the closest phylogenetic species. Hundred twenty-six genes (3.3%) were identified as ORFans.

Conclusions

Microbial culturomics can dramatically improve the characterization of the food and environmental microbiota repertoire, deciphering new bacterial species and new genes. Further studies will clarify the geographic specificity and the putative role of these new microbes and their related functional genetic content in environment, health, and disease.

Gracilibacillus kimchii sp. nov., a halophilic bacterium isolated from kimchi

A novel halophilic bacterium, strain K7(T), was isolated from kimchi, a traditional Korean fermented food. The strain is Gram-positive, motile, and produces terminal endospores. The isolate is facultative aerobic and grows at salinities of 0.0-25.0% (w/v) NaCl (optimum 10-15% NaCl), pH 5.5-8.5 (optimum pH 7.0-7.5), and 15-42°C (optimum 37°C). The predominant isoprenoid quinone in the strain is menaquinone-7 and the peptidoglycan of the strain is meso-diaminopimelic acid. The major fatty acids of the strain are anteisio-C15:0, iso-C15:0, and, C16:0 (other components were < 10.0%), while the major polar lipids are diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, and three unidentified lipids. A phylogenetic analysis of 16S rRNA gene sequence similarity showed that the isolated strain was a cluster of the genus Gracilibacillus. High levels of gene sequence similarity were observed between strain K7(T) and Gracilibacillus orientalis XH-63(T) (96.5%), and between the present strain and Gracilibacillus xinjiangensis (96.5%). The DNA G+C content of this strain is 37.7 mol%. Based on these findings, strain K7(T) is proposed as a novel species: Gracilibacillus kimchii sp. nov. The type strain is K7(T) (KACC 18669(T); JCM 31344(T)).

Croceicoccus naphthovorans sp. nov., a polycyclic aromatic hydrocarbons-degrading and acylhomoserine-lactone-producing bacterium isolated from marine biofilm, and emended description of the genus Croceicoccus

A polycyclic aromatic hydrocarbons-degrading and acylhomoserine-lactone-producing marine bacterium, designated strain PQ-2T, was isolated from marine biofilm collected from a boat shell at a harbour of Zhoushan island in Zhejiang Province, PR China. Strain PQ-2T is Gram-stain-negative, yellow-pigmented, non-motile and short rod-shaped. Optimal growth of strain PQ-2T was observed at 32 °C, at pH 7.0 and in 2 % (w/v) NaCl. The 16S rRNA gene sequence of strain PQ-2T showed highest similarity to Croceicoccus marinus E4A9T (96.3 %) followed by Novosphingobium malaysiense MUSC 273T (95.6 %) and Altererythrobacter marinus H32T (95.6 %). Phylogenetic analysis with all species of the family Erythrobacteraceae with validly published names revealed that strain PQ-2T formed a phyletic line with Croceicoccus marinus E4A9T that was distinct from other members of the family Erythrobacteraceae . The sole respiratory quinone was ubiquinone 10 (Q-10). The predominant fatty acids were C18 : 1ω7c, C17 : 1ω6c and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH). The genomic DNA G+C content was 61.7 mol%. In the polar lipid profile, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, one unidentified phospholipid and one sphingoglycolipid were the major compounds; and another sphingoglycolipid was present in a minor amount. Based on the genotypic and phenotypic data, strain PQ-2T represents a novel species of the genus Croceicoccus , for which the name Croceicoccus naphthovorans sp. nov. is proposed. The type strain is PQ-2T ( = CGMCC 1.12805T = NBRC 110381T). In addition, emended descriptions for the genus Croceicoccus and the species C. marinus are given.

Flavobacterium palustre sp. nov., isolated from wetland soil

A Gram-staining-negative, non-motile, yellow-coloured, rod-shaped bacterium, designated S44(T), was isolated from bankside soil of Xixi wetland, located in Zhejiang province, China. Growth of strain S44(T) was observed at 6-37 °C (optimum, 28 °C) and at pH 6.0-9.0 (optimum, 7.0). No growth occurred in the presence of >2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain S44(T) represented a member of the genus Flavobacterium, showing the highest sequence similarities to the sequences from Flavobacterium succinicans DSM 4002(T) (96.9 %), Flavobacterium reichenbachii WB 3.2-61(T) (96.6 %) and Flavobacterium glycines NCBI 105008(T) (96.5 %). The G+C content of the genomic DNA was 33.6 mol%. The predominant cellular fatty acids were C15 : 0, iso-C15 : 0, anteiso-C15 : 0 and summed feature 3 (comprising C16 : 1ω7c and/or iso-C15 : 0 2-OH), and the major respiratory quinone was menaquinone 6 (MK-6). The major polar lipids were phosphatidylethanolamine, two unknown aminolipids, two unknown aminophospholipids and four unknown polar lipids. On the basis of the phenotypic and genotypic data, it is proposed that the isolate S44(T) be classified as representing a novel species of the genus Flavobacterium, for which the name Flavobacterium palustre sp. nov. is proposed. The type strain is S44(T) ( = CGMCC 1.12811(T) = NBRC 110389(T)).

Pedobacter xixiisoli sp. nov., isolated from bank soil

A Gram-stain-negative, rod-shaped, yellow, non-motile, aerobic bacterium (strain S27T) was isolated from bank soil of the Xixi wetland in Zhejiang province, PR China. Phylogenetic analysis, based on its 16S rRNA gene sequence, revealed that strain S27T could represent a novel species of the genus Pedobacter showing highest similarity to Pedobacter koreensis WPCB189T (95.45 %), followed by ‘Pedobacter zeaxanthinifaciens’ TDMA-5 (95.22 %). The temperature, pH and NaCl concentration ranges for growth were 6–37 °C (optimum 28 °C), pH 5.0–9.0 (optimum pH 7.5) and 0–3 % (w/v) [optimum 0.5 % (w/v)], respectively. The DNA G+C content was 36.1 mol%, MK-7 was the only respiratory quinone, and iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) were the major fatty acids. These data all support the affiliation of strain S27T to the genus Pedobacter . The polar lipids of strain S27T comprised phosphatidylethanolamine, one unidentified aminophospholipid, four unidentified aminolipids and three unidentified lipids. However, strain S27T could be distinguished from other members of the genus Pedobacter due to its physiological and biochemical characteristics. Therefore, strain S27T represents a novel species of the genus Pedobacter , for which the name Pedobacter xixiisoli sp. nov. is proposed; the type strain is S27T ( = CGMCC 1.12803T = NBRC 110388T).

Sphingobacterium paludis sp. nov., isolated from wetland soil

A novel Gram-stain-negative bacteria, designated S37T, was isolated from soil of the Xixi wetland, Zhejiang province, China. Cells of strain S37T were aerobic, non-motile rods. Growth occurred at 10–37 °C (optimum, 25 °C), pH 5.0–9.7 (optimum, pH 7.5) and with 0–6 % (w/v) NaCl (optimum, 0.5 %). Based on 16S rRNA gene sequence analysis, strain S37T was found to be a member of the genus Sphingobacterium and shared highest similarity with Sphingobacterium composti 4M24T (95.78 %). The major fatty acids were summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), iso-C15 : 0 and iso-C17 : 0 3-OH, and the DNA G+C content was 43.8 mol%. The predominant respiratory quinone was MK-7. Based on its phenotypic and chemotaxonomic characteristics and phylogenetic data, strain S37T represents a novel species of the genus Sphingobacterium , for which the name Sphingobacterium paludis sp. nov. (type strain S37T = CGMCC 1.12801T = NBRC 110386T) is proposed.

Epilithonimonas xixisoli sp. nov., isolated from wetland bank-side soil

A novel Gram-staining-negative, non-motile and rod-shaped bacterial strain containing flexirubin-type pigments, designated S31(T), was isolated from bank-side soil of the Xixi wetland in Zhejiang province, China. Growth occurred at 10-37 °C (optimum, 32 °C), pH 6-8 (optimum, pH 7) and with 0-2 % (w/v) NaCl (optimum, 1 %). Strain S31(T) shared highest 16S rRNA gene sequence similarities with Epilithonimonas lactis H1(T) (96.2 %) and Chryseobacterium molle DW3(T) (96.4 %). Phylogenetic analysis suggested that strain S31(T) was a member of the genus Epilithonimonas. The dominant respiratory quinone was MK-6 and the DNA G+C content was 33.3 mol%. The major fatty acids were iso-C15 : 0, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c) and anteiso-C15 : 0. The major polar lipids of strain S31(T) were phosphatidylethanolamine, three unidentified aminolipids and four unidentified polar lipids. Based on its phenotypic and chemotaxonomic characteristics and phylogenetic data, strain S31(T) represents a novel species of the genus Epilithonimonas, for which the name Epilithonimonas xixisoli sp. nov. (type strain S31(T) = CGMCC 1.12802(T) = NBRC 110387(T)) is proposed.

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.

Gracilibacillus alcaliphilus sp. nov., a facultative alkaliphile isolated from indigo fermentation liquor for dyeing

A facultatively alkaliphilic, lactic-acid-producing and halophilic strain, designated SG103T, was isolated from a fermented Polygonum indigo (Polygonum tinctorium Lour.) liquor sample for dyeing prepared in a laboratory. 16S rRNA gene sequence phylogeny suggested that SG103T is a member of the genus Gracilibacillus with the closest relatives being ‘Gracilibacillus xinjiangensis’ J2 (similarity: 97.06 %), Gracilibacillus thailandensis TP2-8T (97.06 %) and Gracilibacillus halotolerans NNT (96.87 %). Cells of the isolate stained Gram-positive and were facultatively anaerobic straight rods that were motile by peritrichous flagella. The strain grew at temperatures between 13 and 48 °C with the optimum at 39 °C. It grew in the range pH 7–10 with the optimum at pH 9. The isoprenoid quinone detected was menaquinone-7 (MK-7) and the DNA G+C content was 41.3 mol%. The whole-cell fatty acid profile mainly (>10 %) consisted of iso-C15 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. Unlike other reported species of the genus Gracilibacillus , the strain lacked diphosphatidylglycerol as a major polar lipid. DNA–DNA hybridization experiments with strains exhibiting greater than 96.87 % 16S rRNA gene sequence similarity, ‘G. xinjiangensis’ J2, G. thailandensis TP2-8T and G. halotolerans NNT, revealed 2±4 %, 4±9 % and 3±2 % relatedness, respectively. On the basis of the differences in phenotypic and chemotaxonomic characteristics, and the results of phylogenetic analyses based on 16S rRNA gene sequences and DNA–DNA relatedness data from reported species of the genus Gracilibacillus , strain SG103T merits classification as a members of a novel species, for which the name Gracilibacillus alcaliphilus sp. nov. is proposed. The type strain is SG103T ( = JCM 17253T = NCIMB 14683T).

Halopelagius longus sp. nov., a member of the family Halobacteriaceae isolated from a salt mine, and emended description of the genus Halopelagius

A thermotolerant, extremely halophilic archaeon, BC12-B1T, was isolated from a salt mine in Baicheng county, Xinjiang province, China. Colonies were off-white–grey. The cells stained Gram-negative, were motile and irregularly long-rod-shaped (variation in both width and length) with abundant gas vesicles. The strain was able to grow at 20–55 °C (optimum, 48 °C), at pH 6.0–8.0 (optimum, 7.0–7.3), with 1.8–6.0 M NaCl (optimum, 3.0–3.5 M) and with 0.02–2.2 M Mg2+ (optimum, 0.1–0.2 M). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 8 % (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain BC12-B1T was most closely related to Halopelagius inordinatus RO5-2T (98.5 %) with less than 95 % sequence similarity to other described species. The genomic DNA G+C content of strain BC12-B1T was 64.0 mol%. The DNA–DNA hybridization value between strain BC12-B1T and Hpl. inordinatus RO5-2T was 43.6 %. The major polar lipids of strain BC12-B1T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, four glycolipids and an unknown lipid. Based on phenotypic, chemotaxonomic and genotypic characteristics, strain BC12-B1T represents a novel species of the genus Halopelagius , for which the name Halopelagius longus sp. nov. is proposed. The type strain is BC12-B1T ( = CGMCC 1.12397T = JCM 18758T). An emended description of the genus Halopelagius is also provided.

Gracilibacillus marinus sp. nov., isolated from the northern South China Sea

Two gram-positive, aerobic, spore-forming, rod-shaped bacteria, designated HB09003(T) and HB12160, were isolated from seawater and sediment in the northern South China Sea, respectively. Cells were found to be motile by means of peritrichous flagella. The strains were found to grow with 0-15 % (w/v) NaCl, at 10-45 °C and pH 5.0-10.7, with an optimum of 3 % NaCl, 28 °C and pH 8.5, respectively. The predominant isoprenoid quinone of strain HB09003(T), selected as the representative strain, was identified as MK-7. This strain was found to possess anteiso-C15:0, iso-C15:0, anteiso-C17:0 and C16:0 as the major fatty acids. The G+C contents of strain HB09003(T) and HB12160 were determined to be 34.1 and 34.3 mol%, respectively. Analysis of the 16S rRNA gene sequences of the two strains showed an affiliation with the genus Gracilibacillus, with Gracilibacillus kekensis CGMCC 1.10681(T) (similarity of 97.4, 98.0 %, respectively) and Gracilibacillus ureilyticus CGMCC 1.7727(T) (similarity of 97.1, 97.8 %, respectively) as their closest relatives. The DNA-DNA hybridization values between strain HB09003(T) and the two type strains were 42.2 and 54.1 %, respectively. On the basis of phenotypic and genotypic data, strain HB09003(T) and HB12160 are proposed to represent a novel species of the genus Gracilibacillus, for which the name Gracilibacillus marinus sp. nov. is proposed. The type strain is HB09003(T) (=CGMCC 1.10343(T) = DSM 23372(T)).

Gracilibacillus xinjiangensis sp. nov., a new member of the genus Gracilibacillus isolated from Xinjiang region, China

A Gram-positive, endospore-forming, rod-shaped bacterium, designated isolate J2(T) was isolated from a soil sample from Xinjiang Uyghur Autonomous Region, China. The isolate was observed to grow at 16-46 °C and pH 6.5-8.0. Chemotaxonomic analysis showed menaquinone-7 (MK-7) to be the major isoprenoid quinone; diphosphatidylglycerol, phosphatidylglycerol, one aminophospholipid, two phosphoglycolipids and one glycolipid as the major cellular polar lipids; and anteiso-C15:0, iso-C15:0, anteiso-C17:0 and C16:0 as the major fatty acids. Comparative analyses of the 16S rRNA gene sequence showed that strain J2(T) is most closely related to Gracilibacillus ureilyticus (with 98.8 % similarity), Gracilibacillus dipsosauri (97.2 %), Gracilibacillus quinghaiensis (97.1 %) and Gracilibacillus thailandensis (97.0 %). The DNA-DNA reassociation values between strain J2(T) and G. ureilyticus MF38(T), G. dipsosauri DD1(T), G. quinghaiensis YIM-C229(T) and G. thailandensis TP2-8(T) were 29.8 ± 3.7, 23.0 ± 3.5, 15.8 ± 4.9 and 15.9 ± 5.0 %, respectively. The genomic DNA G+C content of strain J2(T) was determined to be 36.5 mol%. Based on these data, strain J2(T) is considered as a novel species of the genus Gracilibacillus, for which the name Gracilibacillus xinjiangensis sp. nov. is proposed. The type species is J2(T) (= CGMCC 1.12449(T) = JCM 18859(T)).

Halolamina salifodinae sp. nov. and Halolamina salina sp. nov., two extremely halophilic archaea isolated from a salt mine

Two strictly aerobic, extremely halophilic archaea, strains WSY15-H1(T) and WSY15-H3(T), were isolated from a salt mine in Wensu county, Xinjiang province, China. Cells of the two strains were Gram-stain-negative, non-motile and pleomorphic. Colonies were pink- and red-pigmented, respectively. Strain WSY15-H1(T) grew at 20-45 °C (optimum 37-42 °C), 1.6-5.4 M NaCl (optimum 3.4-3.9 M), 0-2.0 M MgCl2 (optimum 0.1-0.5 M) and pH 6.0-9.0 (optimum 7.0), whereas strain WSY15-H3(T) grew at 20-50 °C (optimum 37 °C), 1.9-5.4 M NaCl (optimum 3.4 M), 0.02-2.5 M MgCl2 (optimum 0.5-1.0 M) and pH 6.0-7.5 (optimum 6.5). The minimal NaCl concentrations to prevent cell lysis were 9 % (w/v) for strain WSY15-H1(T) and 8 % (w/v) for strain WSY15-H3(T). The major polar lipids of the two isolates were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate, as well as nine glycolipids for strain WSY15-H1(T) and seven glycolipids for strain WSY15-H3(T); two of these glycolipids (GL1 and GL3) were chromatographically identical to bis-sulfated diglycosyl diether (S2-DGD-1) and sulfated diglycosyl diether (S-DGD-1), respectively. The genomic DNA G+C contents of strains WSY15-H1(T) and WSY15-H3(T) were 65.4 and 66.2 mol%. On the basis of 16S rRNA gene sequence analysis, strains WSY15-H1(T) and WSY15-H3(T) shared 97.0% similarity with each other and showed respectively 98.4 and 97.6% sequence similarity to Halolamina pelagica TBN21(T), which was the only type strain that had higher than 91% sequence similarity with the two isolates. Analysis of phylogenetic relationships and DNA-DNA relatedness indicated that strains WSY15-H1(T) and WSY15-H3(T) represent two novel lineages with closest affinity to H. pelagica TBN21(T). Based on phenotypic, chemotaxonomic and genotypic characteristics, two novel species of the genus Halolamina are proposed, Halolamina salifodinae sp. nov. (type strain WSY15-H1(T) = JCM 18548(T) = GCMCC 1.12371(T)) and Halolamina salina sp. nov. (type strain WSY15-H3(T) = JCM 18549(T) = GCMCC 1.12285(T)).

Halopiger salifodinae sp. nov., an extremely halophilic archaeon isolated from a salt mine

A novel extremely halophilic archaeon KCY07-B2(T) was isolated from a salt mine in Kuche county, Xinjiang province, China. Colonies were cream-pigmented and cells were pleomorphic rod-shaped. Strain KCY07-B2(T) was able to grow at 25-50 °C (optimum 37-45 °C) and pH 6.0-8.0 (optimum 7.0). The strain required at least 1.9 M NaCl for growth. MgCl2 was not required. Cells lysed in distilled water. Polar lipid analysis revealed the presence of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 glycerol diethers, together with five glyolipids. The bis-sulfated glycolipid S2-DGD-1 was present. The DNA G+C content was 62.5 mol%. Analysis of the 16S rRNA gene sequence revealed that strain KCY07-B2(T) was closely related to Halopiger xanaduensis SH-6(T) and Halopiger aswanensis 56(T) (95.8 % and 95.5 % similarity, respectively). On the basis of its phenotypic, chemotaxonomic and genotypic characteristics, strain KCY07-B2(T) is considered to represent a novel species of the genus Halopiger, for which the name Halopiger salifodinae sp. nov. is proposed. The type strain is KCY07-B2(T) ( = JCM 18547(T) = CGMCC 1.12284(T)).

Extensimonas vulgaris gen. nov., sp. nov., a member of the family Comamonadaceae

A novel strain, named S4(T), was obtained from industrial wastewater in Xiaoshan, Zhejiang Province, China. Cells were Gram-negative, neutrophilic and non-spore-forming and moved by means of a polar flagellum. Normal cells were 0.8-0.9 × 1.3-1.9 µm and the cells elongated to 10-25 µm when cultivated at high temperatures. Strain S4(T) grew at 15-50 °C (optimum at 48 °C), pH 5.5-8.5 (optimum 7.0-7.5) and 0-2% (optimum 0.5%) (w/v) NaCl. Ubiquinone-8 was the predominant respiratory quinone. C16:0, summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH) and C17:0 cyclo were the major cellular fatty acids. The major 3-OH fatty acid was C10:0 3-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unknown aminoglycolipid. The genomic DNA G+C content was 68.8 mol%. Based on 16S rRNA gene sequences alignment, the most closely related strains were members of the genera Comamonas (94.6-95.6% similarities), Giesbergeria (94.9-95.6%), Acidovorax (94.8-95.4%), Brachymonas (94.1-95.2%) and Macromonas (95.1%). Phylogenetic analysis showed the closest relatives of strain S4(T) were members of the genus Macromonas. Based on phenotypic and phylogenetic characteristics, we suggest that strain S4(T) represents a novel species of a new genus of the family Comamonadaceae, for which the name Extensimonas vulgaris gen. nov., sp. nov. is proposed. The type strain of Extensimonas vulgaris is S4(T) (=CGMCC 1.10977(T)=JCM 17803(T)).

Gracilibacillus bigeumensis sp. nov., a moderately halophilic bacterium from solar saltern soil

A Gram-staining-positive, moderately halophilic bacterium, designated strain BH097T, was isolated from solar saltern soil of Bigeum Island in south-west Korea. Cells were motile rods, producing spherical endospores at a terminal position in swollen sporangia. Strain BH097T was strictly aerobic, grew at pH 5.5–9.5 (optimum, pH 8.0), at 10–52 °C (optimum, 37 °C) and at salinities of 1–22 % (w/v) NaCl (optimum, 7 % NaCl). On the basis of 16S rRNA gene sequence analysis, strain BH097T was shown to belong to the genus Gracilibacillus within the phylum Firmicutes , and showed closest sequence similarity to Gracilibacillus saliphilus DSM 19802T (95.8 %), Gracilibacillus thailandensis TP2-8T (95.6 %), Gracilibacillus boraciitolerans DSM 17256T (95.5 %), ‘Gracilibacillus quinghaiensis’ DSM 17858 (95.4 %) and Gracilibacillus halophilus DSM 17856T (95.2 %). The DNA G+C content of this novel isolate was 37.9 mol%. The major cellular fatty acids of strain BH097T were anteiso-C15 : 0, iso-C15 : 0 and C16 : 0, and its polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylglycerol two unknown phospholipids and a glycolipid. The isoprenoid quinone was MK-7, and the peptidoglycan type was A1γ, with meso-diaminopimelic acid as the diagnostic diamino acid. On the basis of polyphasic evidence from this study, strain BH097T represents a novel species of the genus Gracilibacillus for which the name Gracilibacillus bigeumensis sp. nov. is proposed. The type strain is BH097T ( = KCTC 13130T = DSM 19028T).

Gracilibacillus kekensis sp. nov., a moderate halophile isolated from Keke Salt Lake

A novel moderately halophilic bacterium, designated strain K170(T), was isolated from Keke Salt Lake in Qinghai, China. The strain grew with 0-22 % (w/v) NaCl, at 4-50 °C and at pH 6-11, with optimum growth in 3 % (w/v) NaCl, at 40 °C and at pH 8. The predominant respiratory quinone was menaquinone 7 (MK-7). The polar lipids included diphosphatidylglycerol, phosphatidylglycerol, unidentified phospholipids, aminolipids and glycolipids. The major cellular fatty acids were anteiso-C(15 : 0), iso-C(15 : 0) and anteiso-C(17 : 0). The DNA G+C content was 35.8 mol%. Phylogenetic analysis based on the full-length 16S rRNA gene sequence revealed that strain K170(T) was a member of the genus Gracilibacillus. High levels of 16S rRNA gene sequence similarity were found between strain K170(T) and Gracilibacillus boraciitolerans DSM 17256(T) (97.3 %) and Gracilibacillus thailandensis JCM 15569(T) (97.1 %). 16S rRNA gene sequence similarities between strain K170(T) and the type strains of other recognized members of the genus Gracilibacillus were below 97 %. The DNA-DNA hybridization values of strain K170(T) with G. boraciitolerans DSM 17256(T) and G. thailandensis JCM 15569(T) were 21.9 % and 34.3 %, respectively. On the basis of these results, strain K170(T) is considered to represent a novel species of the genus Gracilibacillus, for which the name Gracilibacillus kekensis sp. nov. is proposed; the type strain is K170(T) ( = CGMCC 1.10681(T) = DSM 23178(T)).