Erkin Rahman

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.

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)).

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)).

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)).

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, Peoples 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)).

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)).

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.

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.

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)).