Yuan-Ming Zhang

Frigoribacterium endophyticum sp. nov., an endophytic actinobacterium isolated from the root of Anabasis elatior (C. A. Mey.) Schischk

A novel endophytic actinobacterium, designated EGI 6500707(T), was isolated from the surface-sterilized root of a halophyte Anabasis elatior (C. A. Mey.) Schischk collected from Urumqi, Xinjiang province, north-west China, and characterized using a polyphasic approach. Cells were Gram-stain-positive, non-motile, short rods and produced white colonies. Growth occurred at 10-45 °C (optimum 25-30 °C), at pH 5-10 (optimum pH 8) and in presence of 0-4% (w/v) NaCl (optimum 0-3%). The predominant menaquinone was MK-9. The diagnostic phospholipids were diphosphatidylglycerol and phosphatidylglycerol. The major fatty acids were anteiso-C(15 : 0), anteiso-C(17 : 0) and iso-C(16 : 0). The DNA G+C content of strain EGI 6500707(T) was 69.1 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain EGI 6500707(T) should be placed in the genus Frigoribacterium (family Microbacteriaceae , phylum Actinobacteria ), and that the novel strain exhibited the highest 16S rRNA gene sequence similarity to Frigoribacterium faeni JCM 11265(T) (99.1%) and Frigoribacterium mesophilum MSL-08(T) (96.5%). DNA-DNA relatedness between strain EGI 6500707(T) and F. faeni JCM 11265(T) was 47.2%. On the basis of phenotypic and chemotaxonomic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strain EGI 6500707(T) represents a novel species of the genus Frigoribacterium , for which the name Frigoribacterium endophyticum sp. nov. is proposed. The type strain is EGI 6500707(T) ( = JCM 30093(T) = KCTC 29493(T)).

Nesterenkonia rhizosphaerae sp. nov., an alkaliphilic actinobacterium isolated from rhizosphere soil in a saline-alkaline desert.

An alkaliphilic actinobacterial strain, designated EGI 80099(T), was isolated from a rhizosphere soil sample of Reaumuria soongorica found in the desert soils of Fukang, Xinjiang, north-west China. Cells of strain EGI 80099(T) were Gram-stain-positive, non-motile, non-endospore-forming cocci. The predominant menaquinones were MK-7, MK-8 and MK-9. The major cellular fatty acids (>10 %) were anteiso-C15 : 0 and anteiso-C17 : 0. Analysis of the cell wall showed the presence of peptidoglycan of the type l-Lys-Gly-l-Glu, variation A4α. Cells of the isolate contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, an unknown phospholipid and an unidentified glycolipid as polar lipids. The genomic DNA G+C content was 63.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain EGI 80099(T) belongs to the genus Nesterenkonia, sharing 95.68-97.37 % sequence similarities with the type strains of recognized species within this genus. DNA-DNA hybridization of strain EGI 80099(T) with the type strains of species that showed the highest sequence similarities, Nesterenkonia aethiopica DSM 17733(T) (97.37 %), Nesterenkonia flava CAAS 251(T) (97.23 %) and Nesterenkonia xinjiangensis YIM 70097(T) (97.02 %), gave relatedness values of 8.7-62.2 %. Data from DNA-DNA hybridizations and physiological and biochemical tests indicated that strain EGI 80099(T) represents a novel species of the genus Nesterenkonia, for which the name Nesterenkonia rhizosphaerae sp. nov. is proposed. The type strain is EGI 80099(T) ( = BCRC 16947(T) = JCM 19129(T)).

Halopelagius fulvigenes sp. nov., a halophilic archaeon isolated from a lake

Two extremely halophilic archaea, designated YIM 94188(T) and YIM 94189, were isolated from Qijiaojing lake in Xinjiang province, north-west China and subjected to taxonomic characterization using a polyphasic approach. The cells of the two strains were coccoid, non-motile and Gram-stain-negative. Colonies were pink-white-pigmented and aerobic. Growth occurred at 10-30% (w/v) NaCl, 20-55 °C and pH 6.0-8.0 (optimum: 20-25% NaCl, 37-42 °C, pH 6.5-7.0). Magnesium was necessary for growth in the range of 0.2-1.2 M. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two strains belonged to the genus Halopelagius showing 98.5% sequence similarity to the closest phylogenetic neighbour, Halopelagius inordinatus RO5-2(T). In addition, the DNA-DNA hybridization values of strains YIM 94188(T) and YIM 94189 to Halopelagius inordinatus RO5-2(T) were 35.7% and 37.7%, respectively. Polar lipid analyses revealed that the two strains contained phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1). The DNA G+C contents of strains YIM 94188(T) and YIM 94189 were 66.3 mol% and 64.6 mol%, respectively. On the basis of physiological and chemotaxonomic data, and phylogenetic analysis, strains YIM 94188(T) and YIM 94189 were classified as representing a novel species in the genus Halopelagius. The name Halopelagius fulvigenes sp. nov. is proposed, with YIM 94188(T) (=CCTCC AB 2010456(T)=JCM 17506(T)) as the type strain.

Nocardiopsis ansamitocini sp. nov., a new producer of ansamitocin P-3 of the genus Nocardiopsis.

An alkalitolerant actinomycete strain, designated EGI 80425T, capable of producing ansamitocin P-3, was isolated from a saline-alkali soil sample of Xinjiang province, north-west China, and subjected to a polyphasic taxonomic characterization. Strain EGI 80425T formed non-fragmented substrate mycelia and white aerial hyphae with long spore chains. Whole-cell hydrolysates of the isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and rhamnose as the major sugar. The major fatty acids were anteiso-C17 : 0, iso-C16 : 0 and C18 : 1ω9c. The predominant menaquinones were MK-10(H4), MK-10(H6), MK-10(H8) and MK-9(H4). The G+C content of the genomic DNA of strain EGI 80425T was 70.2 mol%. Strain EGI 80425T showed highest 16S rRNA gene sequence similarity to Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111T (96.44 %). Phylogenetic analysis showed that strain EGI 80425T clustered with the members of the genus Nocardiopsis. Based on phenotypic, chemotaxonomic and phylogenetic characteristics, strain EGI 80425T represents a novel species of the genus Nocardiopsis, for which the name Nocardiopsis ansamitocini sp. nov. is proposed. The type strain is EGI 80425T ( = CGMCC 9969T = KCTC 39605T).

Haloactinopolyspora alkaliphila sp. nov., and emended description of the genus Haloactinopolyspora

A facultatively alkaliphilic actinomycete strain, designated EGI 80088(T), was isolated from a saline-alkali soil sample from Xinjiang province, north-west China, and subjected to a polyphasic taxonomic characterization. Strain EGI 80088(T) formed fragmented aerial hyphae and short spore chains, and rod-like spores aggregated at maturity. Whole-cell hydrolysates of the isolate contained ll-diaminopimelic acid as the diagnostic diamino acid, and glucosamine, mannose, galactose, glucose and rhamnose as the marker sugars. The major fatty acids identified (>5%) were anteiso-C(15 : 0), iso-C(15 : 0), summed feature 4 (iso-C(17 : 1)I/anteiso-C(17 : 1)B), iso-C(16 : 0) and anteiso-C(17 : 0). The predominant menaquinone was MK-9(H4). The G+C content of the genomic DNA of strain EGI 80088(T) was 70.6 mol%. EGI 80088(T) showed the highest 16S rRNA gene sequence similarity to its closest phylogenetic neighbour Haloactinopolyspora alba YIM 93246(T) (98.5%). The DNA-DNA relatedness value of the strain EGI 80088(T) and H. alba YIM 93246(T) was 59.3±5.2%. On the basis of morphological, chemotaxonomic and phylogenetic characteristics and DNA-DNA hybridization data, strain EGI 80088(T) represents a novel species of the genus Haloactinopolyspora, for which the name Haloactinopolyspora alkaliphila sp. nov. (type strain EGI 80088(T) = BCRC 16946(T) = JCM 19128(T)) is proposed. The description of the genus Haloactinopolyspora has also been emended.

Egibacter rhizosphaerae gen. nov., sp. nov., an obligately halophilic, facultatively alkaliphilic actinobacterium and proposal of Egibaceraceae fam. nov. and Egibacterales ord. nov.

A novel obligately halophilic, facultatively alkaliphilic actinobacterium, designated EGI 80759T, was isolated from the rhizosphere of Tamarix hispida Willd, Karamay, Xinjiang province, north-west China. Cells of strain EGI 80759T were Gram-stain-positive, non-motile and non-endospore-forming rods. Strain EGI 80759T showed obligately halophilic growth with a tolerance to 8-25 % (w/v) NaCl (optimum growth at 10-12 %, w/v) and facultatively alkaliphilic growth within the pH range 7.0-11.0 (optimum growth at pH 9.0-10.0). Cell-wall hydrolysates of the isolate contained meso-diaminopimelic acid (peptidoglycan type A1γ), with glucose, glucosamine, ribose and mannose as the major sugars. The major fatty acids identified were 10-methyl-C17 : 0, C17 : 1ω8c and C17 : 0. The predominant menaquinone was MK-9(H4). The G+C content of the genomic DNA was 72.1 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain EGI 80759T clustered with members of the class Nitriliruptoria and showed highest 16S rRNA gene sequence similarities with Euzebya tangerina F10T (90.3 %) and Nitriliruptor alkaliphilus ANL-iso2T (88.1 %). On the basis of the data obtained from phenotypic and chemotaxonomic studies and the phylogenetic analysis, the isolate is proposed to be a representative of a novel genus and a novel species, Egibacter rhizosphaerae gen. nov., sp. nov., of a proposed novel family, Egibacteraceae fam. nov., and order, Egibacterales ord. nov., within the class Nitriliruptoria. The type strain of the type species, Egibacter rhizosphaerae, is EGI 80759T ( = CGMCC 1.14997T = KCTC 39588T).