Two obligate anaerobic bacterial strains, B71 T and D471, were isolated from cattle rumen. The novel strains were Gram-positive and rod-shaped. The strains hydrolysed xylan and starch, fermented some mono-, di-and oligosaccharides and produced formic, acetic and lactic acids as end products from glucose. Growth of the isolates was observed at 20-55 6C and pH 6?5-9?0. The DNA G+C contents of strains B71 T and D471 were 68?06 and 68?26 mol%, respectively. Although the two novel strains met the genus description for Actinomyces, some phenotypic characteristics, such as optimum growth temperature, requirement for O 2 and the end products of fermentation, distinguished them from previously described members of the genus. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the novel strains belonged to the genus Actinomyces (88?3-93?6 % sequence similarity) and formed a distinct line within the clade containing Actinomyces bovis. On the basis of these results, a novel species, Actinomyces ruminicola sp. nov., is proposed. The type strain is B71 T (=JCM 13352 T =CGMCC 1.5030 T ).

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Nitrogen is the key factor for plant survival and growth, especially in the desert. Stipagrostis pennata, a sand born drought-resistant plant, could colonize pioneerly in Gurbantunggut Desert during revegetation. One strategy for their environment adaptation was the rhizosheath formatted by root-hair, mucilaginous exudates, microbial components, and soil particles, for which not only provides a favorable living microenvironment but also supplies essential nutrients. To understand the relationship between microorganisms living in rhizosheaths and the nitrogen nutrition supply, the microbial diversity and nitrogenase activity was estimated during the growth of S. pennata. Five samples of the rhizosheath, which based on the development periods of the plant, regreen, flowering, filling, seed maturating, and withering period, were collected. The nitrogenase activity was estimated by acetylene reduction and the microbial diversity was analyzed by 16S rRNA high-throughput sequencing. The results showed that the nitrogenase activity was increased slowly during regreen to flowering, while reached a peak rapidly at filling sample and then decreased gradually. A total of 274 operational taxonomic units (OTUs) were identified and significant differences in community structure and composition at each growth period. Among them, the main phyla included Actinobacteria and Proteus, which were the most abundant phyla in all periods. In addition, the microbial diversity in the grain filling period was higher than other periods in view of the analysis of alpha diversity and beta diversity. Furthermore, principal component analysis (PCA) analysis showed that the microbial communities in the filling period was low in similarity with other periods. Most importantly, the OTUs associated with nitrogen fixation is the most during the filling period, involving Phagecidae and Fucoraceae. Overall, the study not only revealed the differences in nitrogenase activity among different developmental periods in S. pennata, but also explored the potential bridges between it and community structure and diversity of bacteria. K E Y W O R D S16S rRNA Miseq, microbiome, nitrogenase activity, Stipagrostis pennata J Cell Biochem. 2019;120:13501-13508.wileyonlinelibrary.com/journal/jcb

A Gram-stain-negative, rod-shaped, motile bacterium, designated AER10T , was isolated from the roots of Ammodendron bifolium collected from Takeermohuer desert in Xinjiang Uygur Autonomous Region, northwestern China. Growth was found to occur from 10 to 45 C, at pH 5.0-9.0, and could tolerate up to 10 % (w/v) NaCl. 16S rRNA gene sequence result indicated that the strain AER10T belongs to the genus Alcaligenes and was closely related to Alcaligenes aquatilis (98.4 %), Alcaligenes faecalis subsp. parafaecalis (98.4 %), Alcaligenes faecalis subsp. faecalis (98.1 %) and Alcaligenes faecalis subsp. phenolicus (97.9 %). However, the DNA-DNA hybridization values between the strain AER10 T and the above strains were less than the threshold value (below 70 %) for the delineation of genomic species. The DNA G+C content was 53.3 mol%. Ubiquinone-8 (Q-8) was the only quinone system present. The major fatty acids were summed feature 8 (C 18 : 1 !7c, 25 %), C 16 : 0 (24.2 %), summed feature 3 (C 16 : 1 !7c and/or C 16 : 1 !6c, 19.3 %) and cyclo-C 17 : 0 (10.5 %). The polar lipid profile of the strain AER10 T

A bacterial strain, designated YZGR15T, was isolated from the root of an annual halophyte Suaeda aralocaspica, collected from the southern edge of the Gurbantunggut desert, north-west PR China. Cells of the isolate were Gram-stain-positive, facultatively anaerobic, irregular rods. Growth occurred at 4–42 °C (optimum, 30–37 °C), at pH 6.0–9.0 (optimum, pH 7.0–7.5) and in the presence of 0–9 % (w/v) NaCl (optimum, 2–5 %). Phylogenetic analysis using 16S rRNA gene sequences indicated that strain YZGR15T showed the highest sequence similarity to Sanguibacter keddieii (98.27 %), Sanguibacter antarcticus (98.20 %) and Sanguibacter inulinus (98.06 %). Results of genome analyses of strain YZGR15T indicated that the genome size was 3.16 Mb, with a genomic DNA G+C content of 71.9 mol%. Average nucleotide identity and digital DNA–DNA hybridization values between strain YZGR15Tand three type strains were in the range of 76.5–77.8 % and 20.0–22.2 %, respectively. Analysis of the cellular component of strain YZGR15T revealed that the primary fatty acids were anteiso-C15 : 0, C16 : 0, C14 : 0 and iso-C16 : 0 and the polar lipids included diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids and two unidentified glycolipids. The cell-wall characteristic amino acids were glutamic acid, alanine and an unknown amino acid. The whole-cell sugars for the strain were mannose, ribose, rhamnose, glucose and an unidentified sugar. The predominant respiratory quinone was MK-9(H4). Based on the results of genomic, phylogenetic, phenotypic and chemotaxonomic analyses, strain YZGR15T represents a novel species of the genus Sanguibacter , for which the name Sanguibacter suaedae sp. nov. is proposed. The type strain is YZGR15T (=CGMCC 1.18691T=KCTC 49659T)

Li Y., Cheng C., An D. (2017): Characterisation of endophytic bacteria from a desert plant Lepidium perfoliatum L. Plant Protect. Sci., 53: 32-43.Sixty-two endophytic bacteria from the leaves, roots, and stems of healthy Lepidium perfoliatum L. were isolated and characterised. From the results, 89, 87, 90, and 97% isolates could tolerate 12% NaCl, 30% PEG 6000, 50°C and pH 10, respectively. 74% isolates could form a biofilm. Besides, 28 isolates could improve the germination rate of host seeds under different degree of drought stress. These data suggest that the endophyte isolates show considerable resistance to abiotic stress and assist their plant hosts to germinate under drought stress.

A novel actinomycete strain, designated YIM LPA2h(T), was isolated from a sediment sample collected from Lop Nur, Xinjiang Uygur Autonomous Region, North-West China. The taxonomic position of strain YIM LPA2h(T) was investigated by a polyphasic approach. The morphological and chemotaxonomic properties of the isolate were in accordance with the members of the genus Saccharothrix. The 16S rRNA gene sequence of the strain showed highest similarities to Saccharothrix yanglingensis (98.6 %), Saccharothrix longispora (98.4 %) and Saccharothrix hoggarensis (98.3 %). However, the DNA-DNA hybridization values between the new isolate YIM LPA2h(T) and S. yanglingensis, S. longispora and S. hoggarensis were significantly below 70 %. Strain YIM LPA2h(T) was found to contain meso-diaminopimelic acid as diagnostic diamino acid. The major sugars in whole-cell hydrolysates were rhamnose, galactose, mannose, glucose and fructose. The major polar lipids were identified as phosphatidylethanolamine, phosphatidylhydroxylethanolamine, diphosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside. The predominant respiratory menaquinones were MK-9 (H4) and MK-10 (H4). The major fatty acids were C17:1 ω8c (15 %), iso-C15:0 (12 %), anteiso-C15:0 (12 %) and summed feature 3 (C16:1 ω6c/C16:1 ω7c, 10 %). The genomic DNA G+C content of strain YIM LPA2h(T) was determined to be 75 mol %. The genotypic and phenotypic results suggest that strain YIM LPA2h(T) represents a novel species of the genus Saccharothrix, for which the name Saccharothrix lopnurensis sp. nov. is proposed. The type strain is YIM LPA2h(T) (=CGMCC 4.7246(T)=KCTC 39545(T)).