Halobellus limi sp. nov. and Halobellus salinus sp. nov., isolated from two marine solar salterns.

Two halophilic archaea, strains TBN53(T) and CSW2.24.4(T), were characterized to elucidate their taxonomic status. Strain TBN53(T) was isolated from the Taibei marine solar saltern near Lianyungang city, Jiangsu province, China, whereas strain CSW2.24.4(T) was isolated from a saltern crystallizer in Victoria, Australia. Cells of the two strains were pleomorphic, stained Gram-negative and produced red-pigmented colonies. Strain TBN53(T) was able to grow at 25-55 °C (optimum 45 °C), with 1.4-5.1 M NaCl (optimum 2.6-3.9 M NaCl), with 0-1.0 M MgCl(2) (optimum 0-0.1 M MgCl(2)) and at pH 5.5-9.5 (optimum pH 7.0), whereas strain CSW2.24.4(T) was able to grow at 25-45 °C (optimum 37 °C), with 2.6-5.1 M NaCl (optimum 3.4 M NaCl), with 0.01-0.7 M MgCl(2) (optimum 0.05 M MgCl(2)) and at pH 5.5-9.5 (optimum pH 7.0-7.5). Cells of the two isolates lysed in distilled water. The minimum NaCl concentrations that prevented cell lysis were 8 % (w/v) for strain TBN53(T) and 12 % (w/v) for strain CSW2.24.4(T). The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate, with two glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, respectively. Trace amounts of other unidentified lipids were also detected. On the basis of 16S rRNA gene sequence analysis, strains TBN53(T) and CSW2.24.4(T) showed 94.1 % similarity to each other and were closely related to Halobellus clavatus TNN18(T) (95.0 and 94.7 % similarity, respectively). Levels of rpoB' gene sequence similarity between strains TBN53(T) and CSW2.24.4(T), and between these strains and Halobellus clavatus TNN18(T) were 88.5, 88.5 and 88.1 %, respectively. The DNA G+C contents of strains TBN53(T) and CSW2.24.4(T) were 69.2 and 67.0 mol%, respectively. The level of DNA-DNA relatedness between strain TBN53(T) and strain CSW2.24.4(T) was 25 %, and these two strains showed low levels of DNA-DNA relatedness with Halobellus clavatus TNN18(T) (30 and 29 % relatedness, respectively). Based on these phenotypic, chemotaxonomic and phylogenetic properties, two novel species of the genus Halobellus are proposed to accommodate these two strains, Halobellus limi sp. nov. (type strain TBN53(T) = CGMCC 1.10331(T) = JCM 16811(T)) and Halobellus salinus sp. nov. (type strain CSW2.24.4(T) = DSM 18730(T) = CGMCC 1.10710(T) = JCM 14359(T)).

Development and Validation of a Risk Stratification Model of Pulmonary Ground-Glass Nodules Based on Complementary Lung-RADS 1.1 and Deep Learning Scores.

Purpose: To assess the value of novel deep learning (DL) scores combined with complementary lung imaging reporting and data system 1.1 (cLung-RADS 1.1) in managing the risk stratification of ground-glass nodules (GGNs) and therefore improving the efficiency of lung cancer (LC) screening in China. Materials and Methods: Overall, 506 patients with 561 GGNs on routine computed tomography images, obtained between January 2017 and March 2021, were enrolled in this single-center, retrospective Chinese study. Moreover, the cLung-RADS 1.1 was previously validated, and the DL algorithms were based on a multi-stage, three-dimensional DL-based convolutional neural network. Therefore, the DL-based cLung-RADS 1.1 model was created using a combination of the risk scores of DL and category of cLung-RADS 1.1. The recall rate, precision, accuracy, per-class F1 score, weighted average F1 score (F1weighted), Matthews correlation coefficient (MCC), and area under the curve (AUC) were used to evaluate the performance of DL-based cLung-RADS 1.1. Results: The percentage of neoplastic lesions appeared as GGNs in our study was 95.72% (537/561) after long-period follow-up.Compared to cLung-RADS 1.1 model or DL model, The DL-based cLung-RADS 1.1 model achieved the excellent performance with F1 scores of 95.96% and 95.58%, F1weighted values of 97.49 and 96.62%, accuracies of 92.38 and 91.77%, and MCCs of 32.43 and 37.15% in the training and validation tests, respectively. The combined model achieved the best AUCs of 0.753 (0.526-0.980) and 0.734 (0.585-0.884) for the training and validation tests, respectively. Conclusion: The DL-based cLung-RADS 1.1 model shows the best performance in risk stratification management of GGNs, which demonstrates substantial promise for developing a more effective personalized lung neoplasm management paradigm for LC screening in China.

Halosarcina limi sp. nov., a halophilic archaeon from a marine solar saltern, and emended description of the genus Halosarcina.

A halophilic archaeon, strain RO1-6(T), was isolated from a marine solar saltern in eastern China. Cells of strain RO1-6(T) were pleomorphic and motile and stained Gram-negative. Strain RO1-6(T) grew well on complex medium and colonies were red-pigmented. It was able to grow at 20-50°C (optimum 37°C), in 2.1-5.1M NaCl (optimum 3.9 M NaCl), in 0.05-0.70 M MgCl2 (optimum 0.30 M MgCl2) and at pH 6.5-8.0 (optimum pH 7.0). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 12 % (w/v). The major polar lipids of strain RO1-6(T) were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two glycolipids that were chromatographically identical to S-DGD-1 and S2-DGD. The 16S rRNA gene sequence of strain RO1-6(T) showed similarities of 96.9 and 96.4 % to those of the type strains of Halosarcina pallida and Halogeometricum borinquense, respectively, members of the most closely related recognized genera within the family Halobacteriaceae. The DNA G+C content of strain RO1-6(T) was 61.2 mol%. Phenotypic characterization and phylogenetic analysis revealed that strain RO1-6(T) is related to Halosarcina pallida and represents a novel species of the genus Halosarcina, for which the name Halosarcina limi sp. nov. is proposed; the type strain is RO1-6(T) (=CGMCC 1.8711(T) =JCM 16054(T)).

Halogeometricum rufum sp. nov., a halophilic archaeon from a marine solar saltern, and emended description of the genus Halogeometricum.

Two halophilic archaea, strains RO1-4(T) and RO1-64, were isolated from a marine solar saltern in Jiangsu, China. Cells of the two strains were pleomorphic, motile, and stained Gram-negative. Colonies were red-pigmented. Strains RO1-4(T) and RO1-64 were able to grow at 25-55 °C (optimum 40-42 °C), at 2.1-5.1 M NaCl (optimum 3.9 M NaCl), at 0.05-0.7 M MgCl(2) (optimum 0.3 M MgCl(2)) and at pH 6.0-8.5 (optimum pH 7.0). Cells lyse in distilled water and the minimal NaCl concentration to prevent cell lysis is 12 % (w/v). On the basis of 16S rRNA gene sequence analysis, strains RO1-4(T) and RO1-64 were closely related to Halogeometricum borinquense PR3(T) (98.0 and 98.2 % similarity, respectively) and Halosarcina pallida BZ256(T) (97.8 and 97.9 %). The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two glycolipids (S-DGD-1 and DGD-1). The DNA G+C contents of strains RO1-4(T) and RO1-64 are 64.9 and 62.4 mol%, respectively. The DNA-DNA hybridization value between strains RO1-4(T) and RO1-64 was 83.0 % and both strains showed low DNA-DNA relatedness with Halogeometricum borinquense PR3(T) (42.5 and 50.1 % relatedness, respectively) and Halosarcina pallida BZ256(T) (37.6 and 42.1 % relatedness). It was concluded that strains RO1-4(T) and RO1-64 represent a novel species of the genus Halogeometricum, for which the name Halogeometricum rufum sp. nov. is proposed. The type strain is RO1-4(T) (=CGMCC 1.7736(T) =JCM 15770(T)).

Intraspecific polymorphism of 16S rRNA genes in two halophilic archaeal genera, Haloarcula and Halomicrobium.

All members of the genera Haloarcula and Halomicrobium whose names have been validly published were surveyed for 16S rRNA gene polymorphism, and the transcription of the genes from two species was investigated during growth at different NaCl concentrations. The species of Haloarcula and Halomicrobium harbour at least two different 16S rRNA gene copies, and 18 new sequences of 16S rRNA genes were obtained. The type I and type II 16S rRNA genes of Haloarcula are divergent at 4.8-5.6% of their nucleotide positions. The type III and type IV 16S rRNA genes from Halomicrobium mukohataei JCM 9738(T) are 9.0% divergent, which represents the highest intraspecific divergent 16S rRNA genes so far seen. Phylogenetic analysis based on 16S rRNA genes indicated that all type I 16S rRNA genes were clustered, and the same was true for the type II 16S rRNA genes of Haloarcula species. The two clusters, respectively generated from type I and type II 16S rRNA genes, were sharply separated and their divergences (4.8-5.6%) are in the range of various divergence usually found between genera in the order Halobacteriales (about 5-10%). Results from reverse transcription-PCR showed that the type I and type II copies of Har. amylolytica BD-3(T) and type III and type IV copies of Hmc. mukohataei JCM 9738(T) were all transcribed to 16S rRNA molecules under different salt concentrations (15-28% NaCl).

Mrakia psychrophila sp. nov., a new species isolated from Antarctic soil.

The yeast strain (Y18) was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 degrees C and 18 degrees C, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB (diazonium blue B) color reaction, urease test, and starch formation were observed. The major CoQ is Q(8). All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakia frigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed.

[Biodiversity of halophilic archaea isolated from two salt lakes in Xin-Jiang region of China].

There are more than 1000 salt lakes situated in northern and western regions of China and 790 of these salt lakes are in Xinjiang Uigur Autonomous Region and Qinghai, Tibet, Inner Mongolia. To better understand halophilic archaeal diversity of salt lakes in Xinjiang, water and sediment samples were collected from two salt lakes, namely Aibi salt lake and Aiding salt lake, and the halophilic archaeal diversity of these samples was determined. Totally eighty-six halophilic archeal strains, of which 56 isolated from Aibi salt lake and 30 isolated from Aiding salt lake, were isolated respectively using CM agar medium. All the strains were subjected to 16S rRNA gene sequencing analysis. Similarity analysis based on 16S rRNA gene sequences of all these strains indicated that the isolates from Aibi salt lake belong to 11 different species of genera Haloarcula, Halobacterium, Halorubrum, Haloterrigena, Natrinema and Natronorubrum, and that the isolates from Aiding salt lake belong to 8 different species of genera Haloarcula, Halobiforma, Halorubrum, Haloterrigena, Natrinema. Among the 86 strains, members of Natronorubrum Natrinema, Halorubrum and Haloterrigena, are dominant groups in Aibi salt lake. However, the dominant group in Aibi salt lake are the members of Natrinema, Halorubrum and Haloterrigena. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains ABH13, ABH 14, ABH 15, ABH 18, ABH 31 and ABH 33 may represent a novel species of Natronorubrum; ABH12, ABH32 and AD30 two novel species of Halorubrum; ABH17 and ABH25, ABH51, ABH52, ABH56 two novel species of Haloterrigena respectively; strain ABH19 a novel species of Haloarcula; strain ABHO7 a novel species of Halobacterium. The Shannon-Wiener's index of Aibi salt lake is 1.899, the same index of Aiding salt lake is 1.317, which indicated that the biodiversity of halophilic archaea from Aibi salt lake was slightly higher than that of Aiding salt lake. Different characteristics in pH of salt concentrations, average annual precipitation, annual evaporation and mankind's impact on two salt lakes might play important roles on halophilic archaeal diversity of two salt lakes.

[Molecular cloning and amino acid composition analysis of a halophilic thiolase gene].

5' and 3' end sequence of acaBl gene as primers, the gene of halophilic thiolase from haloarchae, Halobacterium sp. ZP-6 was cloned and its amino acid composition was calculated. Compared with non-halophilic thiolase, the halophilic thiolase contains more negative charge amino acid, less positive amino acid and less strong hydrophobic amino acid, and use preferably small side-chain amino acid. Those suggest that electrostatic screen, hydrophobic effect and surface tension all contribute to halophilic properties of thiolase.

[Archaeal diversity of Zabuye Lake in Tibet analyzed by culture-independent approach].

With culture-independent approach, microbial DNA was directly extracted from samples of Zabuye saline soda lake. Using the microbial DNA as template, archaeal 16S rDNAs were amplified by PCR. Amplified products were cloned and sequenced. 60 different cloned partial sequences, most of which were related to haloalkaliphilic archaeon, were acquired. In the phylogenetic tree, some clones of Zabuye lake belonged to Genus Natronobacterium, Natrinema, Natronococcus, Natronorubrum, Natronomonas, Halorubrum, Haloterrigena, Halorhabdus in Family Halobacteriaceae. Other clones represent some novel groups. All of them show prolific archaeal diversity of Zabuye lake.

Halorubellus salinus gen. nov., sp. nov. and Halorubellus litoreus sp. nov., novel halophilic archaea isolated from a marine solar saltern.

Two extremely halophilic archaeal strains GX3(T) and GX26(T) were isolated from the Gangxi marine solar saltern near the Weihai city of Shandong Province, China. Cells from the two strains were pleomorphic and stained Gram-negative, colonies were red-pigmented. Strains GX3(T) and GX26(T) were able to grow at 25-50 °C (optimum 37 °C), at 1.4-5.1M NaCl (optimum 3.1M), at pH 5.5-9.5 (optimum pH 7.0) and neither strain required Mg(2+) for growth. Cells lyse in distilled water and the minimal NaCl concentration to prevent cell-lysis was 8% (w/v). The major polar lipids of the two strains were PA (phosphatidic acid), PG (phosphatidylglycerol), PGP-Me (phosphatidylglycerol phosphate methyl ester) and three major glycolipids (GL1, GL2 & GL3) chromatographically identical to S-TGD-1 (sulfated galactosyl mannosy glucosyl diether), S-DGD-1 (sulfated mannosyl glucosyl diether), and DGD-1 (mannosyl glucosyl diether) respectively, an unidentified lipid (GL4) was also detected in strain GX26(T). Phylogenetic analysis based on 16S rRNA gene revealed that strain GX3(T) and strain GX26(T) formed a distinct clade with the closest relative, Haladaptatus paucihalophilus (89.9-92.4% and 90.4-92.7, respectively). The rpoB' gene similarities between strains GX3(T) and GX26(T), and between the two strains and the closest relative, Halorussus rarus TBN4(T) are 96.5%, 84.3% and 83.9%, respectively. The DNA G+C contents of strain GX3(T) and strain GX26(T) are 67.3 mol% and 67.2 mol%, respectively. The DNA-DNA hybridization value between strain GX3(T) and strain GX26(T) was 44%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain GX3(T) and strain GX26(T) represent two novel species in a new genus within the family Halobacteriaceae, Halorubellus salinus gen. nov., sp. nov. (type strain GX3(T)=CGMCC 1.10384(T)=JCM 17115(T)) and Halorubellus litoreus sp. nov. (type strain GX26(T)=CGMCC 1.10386(T)=JCM 17117(T)).

Haloplanus vescus sp. nov., an extremely halophilic archaeon from a marine solar saltern, and emended description of the genus Haloplanus.

An extremely halophilic archaeon, strain RO5-8T, was isolated from a disused marine solar saltern in China. The cells were pleomorphic and flat. In static liquid medium, cells floated to the surface. Strain RO5-8T stained Gram-negative and colonies were pink-pigmented. It was able to grow at 30-50 degrees C (optimum 40 degrees C), at 2.6-4.3 M NaCl (optimum 3.1 M NaCl), at 0.03-0.5 M MgCl2 (optimum 0.03 M MgCl2) and at pH 5.5-7.5 (optimum pH 6.0-6.5). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 12% (w/v). The major polar lipids of strain RO5-8T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one major glycolipid chromatographically identical to the sulfated mannosyl glucosyl diether S-DGD-1. On the basis of 16S rRNA gene sequence analysis, strain RO5-8T was closely related to three strains of Haloplanus natans with similarities of 97.3-97.6%. The DNA G+C content of strain RO5-8T was 62.1 mol%. The DNA-DNA hybridization value between strain RO5-8T and Haloplanus natans JCM 14081T was 51.6%. It was concluded that strain RO5-8T represents a novel species of the genus Haloplanus, for which the name Haloplanus vescus sp. nov. is proposed. The type strain is RO5-8T (=CGMCC 1.8712T =JCM 16055T).

Haladaptatus litoreus sp. nov., an extremely halophilic archaeon from a marine solar saltern, and emended description of the genus Haladaptatus.

Two extremely halophilic archaea, strains RO1-28(T) and RO1-22, were isolated from a marine solar saltern in Jiangsu, China. Both strains required at least 0.05 M Mg(2+) and 1.7 M NaCl for growth. They were able to grow over a pH range of 6.0-8.5 and a temperature range of 25-55 degrees C, with optimal pH of 7.0 and optimal temperature of 37-40 degrees C. Based on 16S rRNA gene sequence analysis, strains RO1-28(T) and RO1-22 were closely related to Haladaptatus paucihalophilus, the single species of the genus Haladaptatus, with similarities of 94.0-95.2 %. The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and three glycolipids chromatographically identical to the glycolipids of Haladaptatus paucihalophilus JCM 13897(T). Both strains RO1-28(T) and RO1-22 had a DNA G+C content of 54.0 mol% (HPLC). The DNA-DNA hybridization value between the two strains was more than 70 % (92 %) and both strains showed low levels of DNA-DNA relatedness (32 % and 33 %) with Haladaptatus paucihalophilus JCM 13897(T). It was concluded that strains RO1-28(T) and RO1-22 represent a novel species of the genus Haladaptatus, for which the name Haladaptatus litoreus sp. nov. is proposed. The type strain is RO1-28(T) (=CGMCC 1.7737(T) =JCM 15771(T)).

Halogranum rubrum gen. nov., sp. nov., a halophilic archaeon isolated from a marine solar saltern.

Two extremely halophilic archaea, strains RO2-11(T) and HO2-1, were isolated from two Chinese marine solar salterns, Rudong solar saltern and Haimen solar saltern, respectively. Cells of the two strains were polymorphic and Gram-stain-negative; colonies were red-pigmented. The two strains grew at NaCl concentrations of 2.6-4.3 M (optimum 3.9 M) and required at least 0.1 M Mg2+ for growth. They were able to grow over a pH range of 6.0-8.0 and a temperature range of 20-50 degrees C, with optimal pH of 7.5 and optimal temperature of 37 degrees C. The major polar lipids of strain RO2-11(T) and strain HO2-1 were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and three glycolipids, two of them chromatographically identical to S-DGD-1 and DGD-1, the third unidentified. The 16S rRNA gene sequence similarity of strain RO2-11(T) and strain HO2-1 was 99.3 % and highest sequence similarity with the closest relative (Haloferax larsenii) was 91.4 %. Based on the data obtained, the two isolates could not be classified in any recognized genus of the family Halobacteriaceae. Strain RO2-11(T) and strain HO2-1 are thus considered to represent a novel species of a new genus within the family Halobacteriaceae, for which the name Halogranum rubrum gen. nov., sp. nov. is proposed. The type strain is RO2-11(T) (=CGMCC 1.7738(T) =JCM 15772(T)).

Halopelagius inordinatus gen. nov., sp. nov., a new member of the family Halobacteriaceae isolated from a marine solar saltern.

Two extremely halophilic archaea, strains RO5-2(T) and RO5-14, were isolated from Rudong marine solar saltern in Jiangsu, China. Cells of the two strains were pleomorphic, motile and stained Gram-negative. Colonies were red-pigmented. Strains RO5-2(T) and RO5-14 were able to grow at 20-50 degrees C (optimum 37 degrees C), at 2.6-4.8 M NaCl (optimum 3.4-3.9 M NaCl), at 0.03-0.7 M MgCl(2) (optimum 0.5 M MgCl(2)) and at pH 5.5-8.0 (optimum pH 6.5-7.0). Cells lyse in distilled water and the minimal NaCl concentration to prevent cell lysis was 12 % (w/v). The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1). The 16S rRNA gene sequences of strains RO5-2(T) and RO5-14 showed 93.4-93.8 % similarity to the closest cultivated relative, Halosarcina pallida. The DNA G+C content of strains RO5-2(T) and RO5-14 was 61.0 mol% and 59.9 mol%, respectively. The DNA-DNA relatedness between strains RO5-2(T) and RO5-14 was 86.0 %. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains RO5-2(T) and RO5-14 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Halopelagius inordinatus gen. nov., sp. nov. is proposed. The type strain is RO5-2(T) (=CGMCC 1.7739(T) =JCM 15773(T)).

Planomicrobium glaciei sp. nov., a psychrotolerant bacterium isolated from a glacier.

A novel aerobic, psychrotolerant, yellow-to-orange bacterium (strain 0423(T)) was isolated from the China No. 1 glacier. Strain 0423(T) displayed phenotypic and chemotaxonomic features of the genus Planomicrobium, containing anteiso-C(15 : 0) and iso-C(14 : 0) as the major fatty acids. The temperature range for growth was 4-28 degrees C, with optimum growth at 20-21 degrees C. The genomic DNA G+C content was 49 mol%. Phylogenetic analysis based on 16S rRNA gene sequence similarity showed that strain 0423(T) was related to members of the genus Planomicrobium, sharing the highest sequence similarities with the type strains of Planomicrobium chinense, P. mcmeekinii, P. okeanokoites and P. koreense. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, a novel species, Planomicrobium glaciei sp. nov., is proposed. The type strain is 0423(T) (=CGMCC 1.6846(T) =JCM 15088(T)).

Flavobacterium tiangeerense sp. nov., a cold-living bacterium isolated from a glacier.

A novel cold-living, Gram-stain-negative, yellow-pigmented and obligately aerobic bacterium designated strain 0563(T) was isolated from the China No. 1 glacier. Phylogenetic analysis showed that strain 0563(T) was a member of the genus Flavobacterium, sharing the highest 16S rRNA gene sequence similarities with Flavobacterium limicola JCM 11473(T) (98.5 %) and Flavobacterium psychrolimnae NBRC 102679(T) (98.2 %). The genomic DNA G+C content was 34.8 mol%. Strain 0563(T) displayed the common phenotypic and chemotaxonomic features of the genus Flavobacterium, containing menaquinone-6 (MK-6) as the major quinone and iso-C(15 : 0), iso-C(15 : 0) 3-OH, summed feature 3 (comprising C(16 : 1)omega7c and/or C(16 : 1)omega6c), C(15 : 1)omega6c, iso-C(15 : 1) G and iso-C(16 : 0) 3-OH as the major fatty acids. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, the novel species Flavobacterium tiangeerense sp. nov. is proposed; the type strain is 0563(T) (=CGMCC 1.6847(T) =JCM 15087(T)).

Marinobacter psychrophilus sp. nov., a psychrophilic bacterium isolated from the Arctic.

Strain 20041(T) was isolated from sea-ice of the Canadian Basin (7 degrees 23' 14'' N 14 degrees 06' 55'' W). Phylogenetic analysis based on 16S rRNA gene homology showed that strain 20041(T) was related to members of the genus Marinobacter and had highest 16S rRNA gene sequence similarity with the type strain of Marinobacter maritimus. Cells were Gram-negative, rod-shaped, psychrophilic and motile. The temperature range for growth was 0-22 degrees C, with optimum growth occurring at 16-18 degrees C and at approximately pH 6.0-9.0. Strain 20041(T) had ubiquinone-9 as the major respiratory quinone and iso-C(15 : 0) 2OH and/or C(16 : 1)omega7c, C(16 : 0), C(18 : 1)omega9c and C(12 : 0) 3OH as major fatty acids. The genomic DNA G+C content was 55.4 mol%. On the basis of the phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strain 20041(T) is considered to represent a novel species, for which the name Marinobacter psychrophilus sp. nov. is proposed. The type strain is 20041(T) (=CGMCC 1.6499(T)=JCM 14643(T)).

Colwellia polaris sp. nov., a psychrotolerant bacterium isolated from Arctic sea ice.

A novel psychrotolerant, Gram-negative, aerobic bacterium, designated strain 537T, was isolated from sea-ice samples from the Arctic. Strain 537T was able to grow at 4-26 degrees C, with optimum growth occurring at 20-21 degrees C. Strain 537T had Q-8 as the major respiratory quinone and contained iso-C15:0 2-OH and/or C16:1 omega7c (22.95 %), C15:1 (17.64 %) and C17:1 omega8c (13.74 %) as the predominant cellular fatty acids. The genomic DNA G+C content was 38.9 mol%. A phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 537T formed a coherent cluster within the genus Colwellia. The highest level of 16S rRNA gene sequence similarity (97.5 %) exhibited by strain 537T was obtained with respect to the type strain of Colwellia aestuarii. On the basis of phenotypic, chemotaxonomic and phylogenetic properties and DNA-DNA relatedness data, strain 537T represents a novel species of the genus Colwellia, for which the name Colwellia polaris sp. nov. is proposed. The type strain is 537T (=CGMCC 1.6132T =JCM 13952T).

Salinibacterium xinjiangense sp. nov., a psychrophilic bacterium isolated from the China No. 1 glacier.

A novel psychrophilic, Gram-positive, yellow-pigmented and aerobic bacterium, strain 0543(T), was isolated from the China No. 1 glacier. Strain 0543(T) was able to grow at 4-23 degrees C, with optimum growth at 18-19 degrees C. The major fatty acids were anteiso-C(15 : 0) (58.36 %), iso-C(16 : 0) (21.13 %), iso-C(14 : 0) (10.25 %) and anteiso-C(17 : 0) (7.16 %). The genomic DNA G+C content was 63.5 mol% and the major menaquinone was MK-10. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 0543(T) represented a lineage within the family Microbacteriaceae, with the highest similarity of 97.4 % with Salinibacterium amurskyense KMM 3673(T). On the basis of polyphasic, chemotaxonomic, physiological and biochemical evidence from this study, the novel species Salinibacterium xinjiangense sp. nov. is proposed; the type strain is 0543(T)(=CGMCC 1.5381(T) =JCM 13926(T)).

Bacillus aidingensis sp. nov., a moderately halophilic bacterium isolated from Ai-Ding salt lake in China.

A Gram-positive, halophilic bacterium was isolated from a sediment sample from Ai-Ding salt lake in China. The isolate, designated strain 17-5(T), grew at salinities of 8-33 % (w/v) NaCl (optimally at 12 %, w/v). The genomic DNA G+C content of strain 17-5(T) was 48.1 mol%. The predominant isoprenoid quinone was MK-7(H(2)) and the cell-wall peptidoglycan contained meso-diaminopimelic acid. The major polar lipids were diphosphatidylglycerol and an unidentified glycolipid. The major cellular fatty acids were anteiso-C(15 : 0), anteiso-C(17 : 0), iso-C(16 : 0) and C(16 : 0). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 17-5(T) was a member of the genus Bacillus, being most closely related to Bacillus qingdaonensis JCM 14087(T) (96.0 % sequence similarity) and Bacillus salarius DSM 16461(T) (95.6 %). The levels of 16S rRNA gene sequence similarity with respect to other Bacillus species were less than 91.7 %. Comparative analysis of the 16S rRNA gene sequence data, chemotaxonomy and phenotypic features of the novel isolate and related species of Bacillus indicated that strain 17-5(T) represents a novel species within the genus Bacillus, for which the name Bacillus aidingensis sp. nov. is proposed. The type strain is 17-5(T) (=CGMCC 1.3227(T)=DSM 18341(T)).