Diversity analysis of Populus euphratica endophytic bacteria in Tarim River Basin, China.

The bacterial diversity in Populus euphratica stem storage liquid samples grown in Shaya County and Yuli County of the Tarim River Basin was investigated. A culture-dependent (dilution spread plate method) and culture-independent method (PCR-RFLP technique) were used to identify the endophytic bacteria community structure and composition in P. euphratica in Tarim River Basin. Sixty-six bacterial strains were isolated from P. euphratica stem storage liquid samples on three agar media. The 16S rDNA gene was amplified and sequenced using bacterial universal primers. Phylogenetic analysis showed that the 66 strains belonged to three phyla (Firmicutes, Actinomycetes, and Gamma-Proteobacteria) and included 16 genera and 29 species. Among them, Pseudomonas (27.27%) and Bacillus (19.69%) were the dominant isolates. CGM-17 was a potentially new species of Pantoea. Restriction fragment length polymorphism of 16S rDNA gene amplified by polymerase chain reaction (PCR-RFLP) revealed 48 operational taxonomic units (OTUs). Phylogenetic analysis indicated that the 48 OTUs belonged to Firmicutes, Actinobacteria, Proteobacteria (α-, ß-, γ-subgroup), Bacteroidetes, and Verrucomicrobia. Gamma-Proteobacteria was the dominant group, similarly to the culture-dependent method, accounting for 53% of the entire bacterial clone library. Our results indicate that P. euphratica endophytic bacteria diversity in the Tarim River Basin was rich, and the resources of endophytic bacteria were high. They provide valuable reference data and species resources for screening indigenous and functional strains of endophytic bacteria in P. euphratica.

Nesterenkonia ebinurensis sp. nov., a Novel Actinobacterium Isolated From Populus euphratica.

During our studies focused on the microorganism diversity and community structure of Populus euphratica at Ebinur lake wetland nature reserve in Xinjiang Uyghur Autonomous Region, PR China, a Gram-positive, aerobic, short rod-shaped bacterium without flagellum, designated as MD2T, was isolated from a piece of resina on Populus euphratica. The isolate grew at temperature of 10-45 °C (optimum 37 °C), pH of 7.0-12.0 (optimum pH 8.0) and NaCl concentration of 1-18% (optimum 3%, w/v). Based on the 16S rRNA gene sequences and the phylogenetic analysis, the strain shared the highest sequence similarities to Nesterenkonia alkaliphila JCM 19766T (96.3%), Nesterenkonia populi KCTC 29119T (95.9%), Nesterenkonia alba CCTCC AB 207011T (95.5%), and was placed within the radiation of Nesterenkonia species in the phylogenetic trees. The draft genome of the isolate was sequenced, which comprised 3,739,891 bp with G + C content of 63 mol%, and was annotated to contain 3614 protein-coding genes, 44 tRNA genes and 5 rRNA genes. Chemotaxonomic analysis indicated that the main respiratory quinones were MK-8 and MK-9, the predominant cellular fatty acids were anteiso-C17:0, anteiso-C15:0 and iso-C16:0, the major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol andphosphatidylinositol. According to the phenotypic, chemotaxonomic and phylogenetic features, strain MD2T is considered to represent a novel species, for which the name Nesterenkonia ebinurensis sp. nov. is proposed. The type strain is MD2T (= KCTC 52999T = MCCC 1K03343T).

Pseudomonas lopnurensis sp. nov., an endophytic bacterium isolated from Populus euphratica at the ancient Ugan river.

A Gram-stain negative, aerobic, rod-shaped, motile by a single polar flagellum, non-spore-forming bacterium, designated strain AL-54T, was isolated from the storage liquid in the stems of Populus euphratica tree at the ancient Ugan River in Xinjiang, PR China. Isolated AL-54T grew optimally at pH 7.0 and temperature 35 °C in the presence of 3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence demonstrated that the isolate belonged to the genus Pseudomonas and was closely related to Pseudomonas songnenensis NEAU-ST5-5 T (97.6%), Pseudomonas zhaodongensis NEAU-ST5-21 T (97.5%), Pseudomonas alcaliphila AL15-21T (97.3%), Pseudomonas toyotomiensis HT-3T (97.3%), Pseudomonas oleovorans subsp. lubricantis RS1T (97.3%), Pseudomonas stutzeri ATCC 17588T (97.3%), Pseudomonas chengduensis CGMCC 2318T (97.2%), and Pseudomonas xanthomarina KMM 1447T (97.1%). Multilocus Sequences Analysis (MLSA) of strain AL-54T based on the three housekeeping genes, rpoB, rpoD and gyrB further confirmed the phylogenetic assignment of the isolates. The G+C content was 64.7 mol%. The DNA-DNA hybridization with P. songnenensis NEAU-ST5-5 T, P. zhaodongensis NEAU-ST5-21T, P. alcaliphila AL15-21T, P. toyotomiensis HT-3T, P. oleovorans subsp. lubricantis RS1T, P. stutzeri ATCC 17588T, P. chengduensis CGMCC 2318T and P. xanthomarina KMM 1447T revealed 44.0%, 44.7%, 60.1%, 48.7%, 49.1%, 60.1%, 58.9% and 60.2% relatedness respectively. The predominant quinone system is ubiquinone-9 (Q-9). The major components of the cellular fatty acids (>10%) were summed feature 8 (comprising C18:1 ω7c /C18:1 ω6c), summed feature 3 (comprising C16:1 ω7c /C16:1 ω6c) and C16:0. The detected major polar lipids were phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG) and phosphatidylcholine (PC). On the basis of phenotypic data, chemotaxonomic and phylogenetic properties, strain AL-54T can consider as a novel species within the genus Pseudomonas, for which the name Pseudomonas lopnurensis sp. nov. is proposed. The type strain is AL-54T (= JCM 19136T = CCTCC AB 2013066T = NRRL B-59987T).

Pseudomonas tarimensis sp. nov., an endophytic bacteria isolated from Populus euphratica.

An endophytic bacterium, MA-69T, was isolated from the storage liquid in the stems of Populuseuphratica trees at the ancient Ugan River in Xinjiang, PR China. Strain MA-69T was found to be short rod-shaped, Gram-stain-negative, non-spore-forming, aerobic and motile by means of a monopolar flagellum. According to phylogenetic analysis based on 16S rRNA gene sequences, strain MA-69T was assigned to the genus Pseudomonas with highest 16S rRNA gene sequence similarity of 97.5 % to Pseudomonas azotifigens JCM 12708T, followed by Pseudomonas matsuisoli JCM 30078T (97.5 %), Pseudomonas balearica DSM 6083T (97.1 %), Azotobacter salinestris ATCC 49674T (96.1 %) and Pseudomonas indica DSM 14015T (95.9 %). Analysis of strain MA-69T based on the three housekeeping genes, rpoB, rpoD and gyrB, further confirmed the isolate to be distinctly delineated from species of the genus Pseudomonas. The DNA G+C content of strain MA-69T was 64.1 mol%. DNA-DNA hybridization with Pseudomonas azotifigens JCM 12708T, Pseudomonas matsuisoli JCM 30078T and Pseudomonas balearica DSM 6083T revealed 62.9, 60.1 and 49.0 % relatedness, respectively. The major fatty acids in strain MA-69T were summed feature 3 (25.7 %), summed feature 8 (24.0 %), C19 : 0cyclo ω8c (19.9 %), C16 : 0 (14.6 %) and C12 : 0 (6.3 %). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Q-9 was the major quinone in strain MA-69T. Based on phenotypic, chemotaxonomic and phylogenetic properties, strain MA-69T represents a novel species of the genus Pseudomonas, for which the name Pseudomonas tarimensis sp. nov. is proposed. The type strain is MA-69T (=CCTCC AB 2013065T=KCTC 42447T).

Pseudomonas populi sp. nov., an endophytic bacterium isolated from Populus euphratica.

A Gram-stain negative, aerobic, non-motile, short-rod-shaped bacterium, designated KBL-4-9T, was isolated from the storage liquid in the stems of Populus euphratica trees in Xinjiang, PR China. Strain KBL-4-9T grew at 4-45 °C (optimum 37 °C), 1-3 % (w/v) NaCl (optimum 1 %, w/v) and pH 5.5-9.5 (optimum pH 7.5). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain KBL-4-9T belonged to the genus Pseudomonas and showed the highest 16S rRNA gene sequence similarity of 97.36 % to Pseudomonas pelagia CL-AP6T, followed by Pseudomonas xinjiangensis S3-3T (97.16 %), Pseudomonas sabulinigri J64T (97.15 %) and Pseudomonas xiamenensis C10-2T (96.47 %). Analysis of strain KBL-4-9T based on the three housekeeping genes, rpoB, rpoD and gyrB, further confirmed the phylogenetic assignment of the isolates. The DNA G+C content was 61.6 mol% (sd = 2.19). DNA-DNA hybridization with P. pelagia CL-AP6T, P. xinjiangensis S3-3T and P. sabulinigri J64T revealed 49.3 % (sd = 3.04), 41.2 % and 52.5 % (sd = 4.45) relatedness, respectively. The major cellular fatty acids of strain KBL-4-9T were C16 : 0, C12 : 0, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C17 : 0 cyclo. The major isoprenoid quinone was Q-9. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine. On the basis of phenotypic, chemotaxonomic and phylogenetic properties, strain KBL-4-9T is considered to represents a novel species of the genus Pseudomonas, for which the name Pseudomonas populi sp. nov. is proposed. The type strain is KBL-4-9T ( = JCM 19138T = CCTCC AB 2013069T = NRRL B-59988T).

[Microbiological characteristics of a Lysinibacillus strain isolated from Populous euphratica].

OBJECTIVE: The aim of this study was to identify the microbiological characteristics of a Lysinibacillus strain isolated from storage liquid in the stems of Populus euphratica trees. METHODS: Bacterial morphology and cultivation characteristics were studied by conventional cultivation and dyeing method. Biochemical characteristics, fatty acid components, menaquinone, polar lipids, phylogenetic analyses of 16S rRNA, determination of (G + C) mol% content and DNA- DNA hybridization were studied by polyphasic taxonomic approach. RESULTS: Strain ML-64 is Gram-positive, endospore-forming and rod-shaped. Colonies are pale-yellow, circular and entire margin. Temperature range for growth is between 10 and 45 degrees C (optimum at 37 degrees C ). The pH range for growth is between 6. 0 and 9.0 (optimum at 7.0). NaCl concentration range for growth is between 0 and 6% (optimum 3% ). Cells were positive for lipid esterase, Arginine dihydrolase, urease and Voges-Proskauer test. No sugars were fermented in the API 50CH strips. L-Serine, Methyl Pyruvate, α-Keto-Butyric, Acetoacetic Acid were oxidized. Resistant to polymyxin b (30 µg), novobiocin (30 µg), peillin G (10 U). 16S rRNA gene sequence demonstrated that strain ML-64 was closely related to Lysinibacillus chungkukjangi 2RL3-2T (100%) , Lysinibacillus sinduriensis BLB-1T (99.1%). DNA-DNA relatedness were 82% and 50. 9% with Lysinibacillus chungkukjangi 2RL3-2T and Lysinibacillus massiliensis CIP108446T, respectively. The genomic DNA G + C content of strain ML-64 was 36. 8% (mol). Major fatty acids were iso-C,,, (55. 05% ) and anteiso-C15,0 (20. 70% ). The predominant menaquinone is MK-7. Based on the phenotypic phylogenetic and genotypic analyses, the strain ML-64 is concluded to represent a new mutant strain of the Lysinibacillus chungkukjangi species, GenBank accession number is KC609752. CONCLUSION: As an endophytic bacterium of Populus euphratica, genomic structure of the strain ML-64 was greatly differentiated from the closest strain L. chungkukjangi, and suitably adapted to the endophytic environment of Populus euphratica.

Rhizobium populi sp. nov., an endophytic bacterium isolated from Populus euphratica.

An endophytic bacterium, designated K-38(T), was isolated from the storage liquid in the stems of Populus euphratica trees at the ancient Ugan River in Xinjiang, PR China. Strain K-38(T) was found to be rod-shaped, Gram-stain-negative, aerobic, non-motile and non-spore-forming. Strain K-38(T) grew at temperatures of 25-37 °C (optimum, 28 °C), at pH 6.0-9.0 (optimum, pH 7.5) and in the presence of 0-3 % (w/v) NaCl with 1 % as the optimum concentration for growth. According to phylogenetic analysis based on 16S rRNA gene sequences, strain K-38(T) was assigned to the genus Rhizobium with highest 16S rRNA gene sequence similarity of 97.2 % to Rhizobium rosettiformans W3(T), followed by Rhizobium nepotum 39/7(T) (96.5 %) and Rhizobium borbori DN316(T) (96.2 %). Phylogenetic analysis of strain K-38(T) based on the protein coding genes recA, atpD and nifH confirmed (similarities were less than 90 %) it to be a representative of a distinctly delineated species of the genus Rhizobium. The DNA G+C content was determined to be 63.5 mol%. DNA-DNA relatedness between K-38(T) and R. rosettiformans W3(T) was 48.4 %, indicating genetic separation of strain K-38(T) from the latter strain. The major components of the cellular fatty acids in strain K-38(T) were revealed to be summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c; 57.2 %), C16 : 0 (13.6 %) and summed feature 2 (comprising C12 : 0 aldehyde, C14 : 0 3-OH/iso-C16 : 1 I and/or unknown ECL 10.928; 11.0 %). Polar lipids of strain K-38(T) include phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, two unidentified aminophospholipids and two unidentified phospholipids. Q-10 was the major quinone in strain K-38(T). Based on phenotypic, chemotaxonomic and phylogenetic properties, strain K-38(T) represents a novel species of the genus Rhizobium, for which the name Rhizobium populi sp. nov. is proposed. The type strain is K-38(T) ( = CCTCC AB 2013068(T) = NRRL B-59990(T) = JCM 19159(T)).

Sphingobacterium hotanense sp. nov., isolated from soil of a Populus euphratica forest, and emended descriptions of Sphingobacterium daejeonense and Sphingobacterium shayense.

A novel Gram-staining-negative bacterial strain, designated XH4(T), was isolated from soil of a Populus euphratica forest in the Hotan River valley, Xinjiang Uyghur autonomous region, PR China. The cells were strictly aerobic, non-motile, short rods. The isolate grew optimally at 37 °C and at pH 7.0-8.0. Based on 16S rRNA gene sequence analysis, strain XH4(T) belonged to the genus Sphingobacterium and was closely related to Sphingobacterium mizutaii ATCC 33299(T) (96.1 % sequence similarity). The DNA G+C content was 41.2 mol%. The major polar lipid of strain XH4(T) was phosphatidylethanolamine, and several unidentified polar lipids were also present. Strain XH4(T) showed the typical chemotaxonomic features of the genus Sphingobacterium, with the presence of ceramide phosphorylethanolamine 2 (CerPE-2) as the major ceramide. The major cellular fatty acids of strain XH4(T) were iso-C15 : 0 (34.0 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 20.7 %) and iso-C17 : 0 3-OH (14.7 %). The predominant isoprenoid quinone was MK-7. On the basis of phenotypic data and phylogenetic inference, strain XH4(T) represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium hotanense sp. nov. is proposed. The type strain is XH4(T) ( = NRRL B-59204(T)  = CCTCC AB 209007(T)). Emended descriptions of Sphingobacterium daejeonense and Sphingobacterium shayense are also given.

Rhizobium tarimense sp. nov., isolated from soil in the ancient Khiyik River.

A Gram-negative, non-motile, pale-yellow, rod-shaped bacterial strain, PL-41(T), was isolated from Populus euphratica forest soil at the ancient Khiyik River valley in Xinjiang Uyghur Autonomous Region, People's Republic of China. Strain PL-41(T) grew optimally at 30 °C and pH 7.0-8.0. The major quinone was Q-10. The predominant cellular fatty acids of strain PL-41(T) were summed feature 8 (comprising C18 : 1ω7c and C18 : 1ω6c), C16 : 0 and C19 : 0 cyclo ω8c. Polar lipids of strain PL-41(T) include two unidentified aminophospholipids (APL1, 2), two unidentified phospholipids (PL1, 2), phosphatidylcholine and three unidentified lipids (L1-3). Strain PL-41(T) showed 16S rRNA gene sequence similarity of 97.0-97.5 % to the type strains of recognized species of the genus Rhizobium. Phylogenetic analysis of strain PL-41(T) based on the sequences of housekeeping genes recA and atpD confirmed (similarities are less than 90 %) its position as a distinct species of the genus Rhizobium. The DNA G+C content was 57.8 mol%. DNA-DNA relatedness between strain PL-41(T) and the type strains of Rhizobium huautlense S02(T), Rhizobium alkalisoli CCBAU 01393(T), Rhizobium vignae CCBAU 05176(T) and Rhizobium loessense CCBAU 7190B(T) were 33.4, 22.6, 25.5 and 45.1 %, respectively, indicating that strain PL-41(T) was distinct from them genetically. Strain PL-41(T) also can be differentiated from these four phylogenetically related species of the genus Rhizobium by various phenotypic properties. On the basis of phenotypic properties, phylogenetic distinctiveness and genetic data, strain PL-41(T) is considered to represent a novel species of the genus Rhizobium, for which the name Rhizobium tarimense sp. nov. is proposed. The type strain is PL-41(T) ( = CCTCC AB 2011011(T) = NRRL B-59556(T)).

[Archaeal diversity in sediment of Dunbasitawu salt lake, Xinjiang, China, estimated by 16S rRNA gene sequence analyses].

OBJECTIVE: We surveyed the composition and diversity of uncultured archaea in Xinjiang Dunbasitawu salt Lake sediment. METHODS: Environmental total DNA was directly extracted from the sediment. We constructed clone library of 16S rRNA gene amplified with archaea-specific primers. A total of 59 positive clones were randomly selected from the library and identified by restriction length polymorphism (RFLP) with enzyme Hae III. Clones with the unique RFLP pattern were sequenced, and then by phylogenetic analysis. RESULTS: The clone coverage C value was 89%, and Shannon-Wiener index was 2.69. In total, 21 Operational Taxonomic Units (OTUs) were obtained and affiliated with Euryarchaeota (92%) and Crenarchaeota (8%). The most of clones were affiliated to Halobacterium (24%), Haloarcula (18%), Natronorubrum (14%), and Halorubrum (8%), which belonged to family Halobacteriaceae (88%) with high similarity to that from thalassohaline environment. In addition, 11% of clones had less than 97% similarity with archaea sequences deposited in GenBank database. CONCLUSION: Compared with other similar Hypersaline environments, archaea diversity in Dunbasitawu salt lake was a little lower. The proportion of archara was different, but the composition is consistent. It was implied that some potential new species or lineages maybe exist in Dunbasitawu salt lake.

Pontibacter populi sp. nov., isolated from the soil of a Euphrates poplar (Populus euphratica) forest.

A Gram-negative-staining, rod-shaped, non-motile and pink bacterial strain was isolated from the soil of a Populus euphratica forest located in Xinjiang, China. The strain, designated strain HYL7-15(T), was subjected to a taxonomic analysis using a polyphasic approach. 16S rRNA gene sequence analyses indicated that the isolate belonged to the phylum Bacteroidetes and was related to the genus Pontibacter, with sequence similarities ranging from 93.1 to 95.0% with other species of the genus Pontibacter. Strain HYL7-15(T) contained MK-7 as the predominant menaquinone and its DNA G+C content was 44.9 mol%. The major cellular fatty acids of the novel strain were iso-C(15:0) (16.49%), iso-C(17:0) 3-OH (10.96%) and summed feature 4 (comprising anteiso-C(17:1) B and/or iso-C(17:1) I, 18.46%). The major polar lipids were phosphatidylethanolamine (PE) and phosphatidylglycerol (PG); diphosphatidylglycerol (DPG), three unknown aminophospholipids (APLs) and two unknown phospholipids (PLs) were also detected. On the basis of the evidence presented, it is concluded that strain HYL7-15(T) represents a novel species of the genus Pontibacter, for which the name Pontibacter populi sp. nov. is proposed. The type strain is HYL7-15(T) (=CCTCC AB 206239(T)=NRRL B-59488(T)).

Altererythrobacter xinjiangensis sp. nov., isolated from desert sand, and emended description of the genus Altererythrobacter.

A Gram-negative, rod-shaped, non-motile, strictly aerobic bacterium, strain S3-63(T), was isolated from desert sand of Xinjiang, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S3-63(T) had highest similarity to type strains of the genus Altererythrobacter, i.e. Altererythrobacter marinus H32(T) (97.2% similarity), Altererythrobacter marensis MSW-14(T) (95.9%), Altererythrobacter aestuarii KCTC 22735(T) (95.5%), Altererythrobacter epoxidivorans JCS350(T) (95.1%), Altererythrobacter namhicola KCTC 22736(T) (95.1%), Altererythrobacter luteolus SW-109(T) (95.0%) and Altererythrobacter indicus LMG 23789(T) (93.5%). Growth occurred at 20-37 °C (optimum 30 °C), at pH 7.0-9.0 (optimum pH 8.0) and in 0-3% (w/v) NaCl (optimum 1%). The major respiratory quinone was ubiquinone-10 and the predominant cellular fatty acids were C(18:1)ω7c (50.8%), summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c; 12.6%), C(16:0) (12.3%), C(14:0) 2-OH (7.3%) and C(17:1)ω6c (4.5%). The DNA G+C content was 64.6 mol%. Therefore, the phylogenetic, physiological and chemotaxonomic data demonstrated that strain S3-63(T) represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter xinjiangensis sp. nov. is proposed; the type strain is S3-63(T) (=CCTCC AB 207166(T)=CIP 110125(T)). An emended description of the genus Altererythrobacter is provided.

[Phylogenetic diversity of culturable endophytic bacteria isolated from the Populus euphratica at the disused ancient Ugan river].

OBJECTIVE: The aim of this study was to identify the culturable endophytic bacteria recovered from the Populus euphratica at the disused (122 years ago) ancient Ugan river of middle reachs of Tarim river, and to understand their Phylogenetic diversity and community structure. METHODS: Bacteria were isolated from the storage liquid in the stem of 2 Populus euphratica stands by using 3 types of different cultural medium (Luria-Bertani, Trypticase Soy Agar and Nutrient Agar), followed carry out 16S rDNA identifications and analysis of their biodiversity. RESULTS: A total of 62 phenotypically different isolates were sequenced and according to their 16S rDNA sequence similarities to type strains of described organisms, they have been placed into four phylogenetic groups (1, Firmicutes; 2, Actinobacteria; 3, Alpha Proteobacteria and 4, Gamma Proteobacteria), 18 genera and 32 species. Among them, Bacillus and pseudomonas were the most widely distributed and predominant, occupied the majority of isolates 40.32% and 16.13%, respectively. Isolate KTH-63 (HM371419) formed a distinct clade with Macrococcus brunensis in phylogenetic tree based on 16S rDNA sequence among the family Staphylococcaceae, so it was demonstrated that the KTH-63 represents a potential novel genus and novel species within the family Staphylococcaceae with 92.491% sequence similarity with the described species Macrococcus brunensis of this family. Isolates KLH-1, KLH-21, KLH-18, KLH-25, KNA-3, KTH-8, KTH-14, KTH-20 and KNA-26 with 96.089% - 97.769% sequence similarities to their closely related members were presumed to be potential novel species, and the discovery rate of potential novel species in the endophytic bacterial community of Populus euphratica was reach up to 16.13%. Furthermore, 10 genera and 18 species have been added to the plant endophytic bacterial categoria by the data obtained in this work. CONCLUSION: The result showed that the cultivable endophytic bacterial diversity in Populus euphratica at Ugan river was very abundant and have high percentage of potential novel species, and it have greatly refreshed the plant endophytic bacterial records. The community structure obtained in this study also may be presumed as a miniature of the endophytic bacterial flora in the Populus euphratica during the recent ages before the affect of modern civilization prossessing to Tarim river valley, which deserve further study and exploitation.

Desertibacter roseus gen. nov., sp. nov., a gamma radiation-resistant bacterium in the family Rhodospirillaceae, isolated from desert sand.

A Gram-negative, rod-shaped, strictly aerobic bacterium, strain 2622(T), was isolated from gamma-irradiated soil sampled from the Taklimakan desert in Xinjiang, China. Phylogenetic analyses showed that strain 2622(T) formed a distinct lineage in the family Rhodospirillaceae and shared 91.7 and 90.1 % 16S rRNA gene sequence similarity with its closest relatives, the type strains of Skermanella xinjiangensis and Skermanella aerolata, respectively. The DNA G+C content of strain 2622(T) was 71.4 mol% and the isoprenoid quinone was ubiquinone Q-10. Based on phenotypic and chemotaxonomic data and phylogenetic analysis, strain 2622(T) is considered to represent a novel species of a new genus in the family Rhodospirillaceae, for which the name Desertibacter roseus gen. nov., sp. nov. is proposed. The type strain of Desertibacter roseus is strain 2622(T) ( = CCTCC AB 208152(T)  = KCTC 22436(T)).

Flavitalea populi gen. nov., sp. nov., isolated from soil of a Euphrates poplar (Populus euphratica) forest.

A novel strain, designated HY-50R(T), isolated from soil of a Euphrates poplar (Populus euphratica) forest in Xinjiang, China, was characterized using a polyphasic taxonomic approach. Cells of the isolate were gram-reaction-negative, strictly aerobic, rod-shaped, non-motile, oxidase-negative and catalase-positive. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate was a member of the phylum Bacteroidetes, its closest relatives being Niastella populi THYL-44(T) (93.6 % similarity), Flavisolibacter ginsengisoli Gsoil 643(T) (93.5 %), Terrimonas ferruginea IAM 15098(T) (93.3 %) and Flavisolibacter ginsengiterrae Gsoil 492(T) (93.2 %). The major fatty acids were iso-C(15 : 1) G (11.7 %), iso-C(15 : 0) (19.6 %) and iso-C(17 : 0) 3-OH (19.3 %). The predominant menaquinone of strain HY-50R(T) was MK-7 and the genomic DNA G+C content was 46.8 mol%. Flexirubin-type pigments were not produced. Based on phylogenetic evidence and the results of phenotypic, genotypic and chemotaxonomic analysis, strain HY-50R(T) represents a novel species of a novel genus, for which the name Flavitalea populi gen. nov., sp. nov. is proposed. The type strain is HY-50R(T) ( = CCTCC AB 208255(T)  = NRRL B-59222(T)).

Sphingobacterium shayense sp. nov., isolated from forest soil.

A Gram-staining-negative, yellow-coloured, strictly aerobic, non-spore-forming, rod-shaped bacterium, designated HS39(T), isolated from a soil sample collected from a natural Populus euphratica forest in Xinjiang, China, was characterized using a polyphasic approach. The isolate grew optimally at 30-37 °C, at pH 6.5-8.0 and with 0-3 % NaCl. Analysis of the 16S rRNA gene sequence of strain HS39(T) revealed that it is a member of the genus Sphingobacterium. Sphingobacterium mizutaii ATCC 33299(T) was the nearest relative (94.0 % 16S rRNA gene sequence similarity). The G+C content of the genomic DNA was 40.2 mol%. The major fatty acids were iso-C15:0, iso-C17:0 3-OH and summed feature 3 (comprising C16:1ω6c and/or C16:1ω7c). The predominant isoprenoid quinone was MK-7. On the basis of phenotypic properties and phylogenetic inference, strain HS39(T) represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium shayense sp. nov. is proposed. The type strain is HS39(T) (=CCTCC AB 209006(T) =NRRL B-59203(T)).

Cohnella luojiensis sp. nov., isolated from soil of a Euphrates poplar forest.

A novel strain, HY-22R(T), was isolated from soil of a Euphrates poplar forest in Xinjiang, China. The cells were Gram-positive-staining, rod-shaped and motile by means of peritrichous flagella. Growth occurred at 10-37 degrees C (optimum 30 degrees C), at pH 7.0-8.0 (optimum pH 7.0) and with 0-1 % NaCl. A phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HY-22R(T) was closely related to Cohnella phaseoli GSPC1(T) (96.3 % sequence similarity). The major respiratory quinone was MK-7 and the predominant fatty acids were anteiso-C(15 : 0), iso-C(15 : 0), iso-C(16 : 0) and C(16 : 0). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content was 49.6 mol%. On the basis of the phylogenetic, physiological and chemotaxonomic data, strain HY-22R(T) represents a novel species in the genus Cohnella, for which the name Cohnella luojiensis sp. nov. is proposed. The type strain is HY-22R(T) (=CCTCC AB 208254(T) =NRRL B-59213(T)).

Niastella populi sp. nov., isolated from soil of Euphrates poplar (Populus euphratica) forest, and emended description of the genus Niastella.

A novel bacterial strain, designated THYL-44(T), was isolated from the soil of a Euphrates poplar (Populus euphratica) forest in Xinjiang, China. The cells were strictly aerobic, Gram-staining-negative, non-flagellated, non-motile and filamentous. Growth occurred at 17-37 degrees C (optimum 30 degrees C), at pH 5.0-8.0 (optimum pH 7.0) and with 0-1 % NaCl (w/v; optimum 0 %). Flexirubin pigments were not produced. A phylogenetic analysis based on 16S rRNA gene sequences revealed that strain THYL-44(T) was closely related to Niastella koreensis KACC 11465(T) (95.5 % sequence similarity). The major respiratory quinone was MK-7 and the predominant cellular fatty acids were iso-C(15 : 0) (28.6 %), iso-C(17 : 0) 3-OH (23.9 %) and iso-C(15 : 1) G (17.4 %). The DNA G+C content was 45.2 mol%. Therefore, the phylogenetic, physiological and chemotaxonomic data demonstrated that strain THYL-44(T) represents a novel species of the genus Niastella , for which the name Niastella populi sp. nov. is proposed. The type strain is THYL-44(T) (=CCTCC AB 208238(T)=KCTC 22560(T)). On the basis of new data, an emended description of the genus Niastella is also proposed.

Isolation and identification of an alkaliphilic Bacillus flexus XJU-3 and analysis of its alkaline amylase.

OBJECTIVE: To isolate and identify a new Bacillus strain capable of growing under highly alkaline conditions as alkaline amylase producers and to characterize its enzymatic properties. METHODS: The isolates were sampled from alkaline sewage in Shihezi city, Xinjiang and screened by plating them on the amylase agar medium depending on the halo zone diameter. The alkaline amylase producer with best enzymatic activity was designated as XJU-3. XJU-3 was identified by its physiological and biochemical characteristics, 16S rDNA sequence homology, and the content of its major cellular fatty acids. RESULTS: XJU-3 was a Gram-positive, spore-forming, aerobic, motile rod alkaliphilic bacterium. It can grow at a broad range of pH (4.0-12.5) in Luria broth medium and its optimum growth was at pH 10 and 37 degrees C. Its NaCl tolerance was up to 15%. Its major cellular fatty acids were anteiso-C15:0 and iso-C15:0. Comparative 16S rRNA gene sequence analyses showed that XJU-3 was most closely related to Bacillus flexus, with 99% similarity. The genomic DNA (G+C) content of our isolate was 39.13 mol %. XJU-3 produced extracellular alkaline amylase, and its maximal enzyme activity was observed at 40 degrees C and pH 10.0. More than 70% of the enzymatic activity was remained at pH 13.0. The enzyme activity was strongly enhanced with the presence of Co2+ and Mg2+. CONCLUSION: The strain XJU-3 was confirmed as B. flexus. Owing to its excellent pH tolerance, the kinds of major cellular fatty acids, and several phenotypic characteristics that were different from the description of the reference strain, the strain was further classified as a new variant of the species B. flexus. The enzymatic properties of XJU-3 alkaline amylase indicated its potential in industrial applications.

[Analysis of saccharin and aspirin tasting ability among Mongolians of Xinjiang].

The saccharin and aspirin tasting abilities have been detected and analyzed in 710 individuals (328men, 382women) of Xinjiang Mongol. It is showed that the saccharin taste-blindness ratio among Mongolians was 4.648%,frequency of the recessive gene determining taste-blindness and the dominant gene determining taste ability was 0.2156, and 0.7844 respectively,and its mean testable threshold was 8.00+/-1.34 (0.108mol/L). Distribution of aspirin tasting threshold appeared a distinct curve with double peaks and single bottom,and demonstrated the aspirin tasting ability was a monogenic character. Solution NO.7 (3.00x10(-4)mol/L) at the bottom in the curve was the boundary of taste-blindness. The peak of taste-blindness was at the solution NO.1 (1.7x10(-2)mol/L), and the peak of tasters was at the solution NO.11 (1.25x10(-5)mol/L), The ratio of aspirin taste-blindness was 90.28%. The chi2 test has been used to evaluate the statistical difference in aspirin taste-blindness ratio between male and female, the result showed that there was no significant difference (P>0.90), and the gene determining for aspirin tasting ability located on autosomes.