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In this study, we used 16S rRNA gene sequence analysis to describe the diversity of cultivable endophytic bacteria associated with fennel (Foeniculum vulgare Mill.) and determined their plant-beneficial traits. The bacterial isolates from the roots of fennel belonged to four phyla: Firmicutes (BRN1 and BRN3), Proteobacteria (BRN5, BRN6, and BRN7), Gammaproteobacteria (BRN2), and Actinobacteria (BRN4). The bacterial isolates from the shoot of fennel represented the phyla Proteobacteria (BSN1, BSN2, BSN3, BSN5, BSN6, BSN7, and BSN8), Firmicutes (BSN4, BRN1, and BRN3), and Actinobacteria (BRN4). The bacterial species Bacillus megaterium , Bacillus aryabhattai , and Brevibacterium frigoritolerans were found both in the roots and shoots of fennel. The bacterial isolates were found to produce siderophores, HCN, and indole-3-acetic acid (IAA), as well as hydrolytic enzymes such as chitinase, protease, glucanase, and lipase. Seven bacterial isolates showed antagonistic activity against Fusarium culmorum , Fusarium solani , and Rhizoctonia. solani. Our findings show that medicinal plants with antibacterial activity may serve as a source for the selection of microorganisms that exhibit antagonistic activity against plant fungal infections and may be considered as a viable option for the management of fungal diseases. They can also serve as an active part of biopreparation, improving plant growth. [ABSTRACT FROM AUTHOR]

A bacterial strain designated NYYP31T was isolated from the leaves of an annual halophytes, Suaeda corniculata Bunge, collected from the southern edge of the Gurbantunggut desert, north-west China. Strain NYYP31T was Gram-staining negative, strictly aerobic, rod-shaped, non-motile, and non-spore-forming. Growth was observed at 4–42 °C, at pH 5.0–10.0, in the presence of up to 8% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and coding sequences of 92 protein clusters showed that strain NYYP31T should be assigned to the genus Sphingobacterium. 16S rRNA gene sequence similarity analysis showed that strain NYYP31T was most closely related to the type strain of Sphingobacterium daejeonense (97.9%) and Sphingobacterium lactis (97.7%). The predominant isoprenoid quinone was MK-7. The major fatty acids were identified as iso-C15:0, iso-C17:0 3-OH and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The polar lipids were phosphatidylethanolamine, two unidentified phospholipids, three unidentified lipids, three unidentified amino phospholipids, and two unidentified glycolipids. The genomic DNA G + C content was 36.4 mol%. The average nucleotide identity (ANI) values for strain NYYP31T to the type strains of S. daejeonense and S. lactis were 77.9 and 74.1%, respectively, which were below the cut-off level (95–96%) for species delineation. Based on the above results, strain NYYP31T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium endophyticum sp. nov. is proposed. The type strain is NYYP31T (= CGMCC 1.16979T = NBRC 114258T). [ABSTRACT FROM AUTHOR]

A novel Bacillus strain, designated SYSU G01002T, was isolated from a sediment sample collected from tepid spring in Tengchong, Yunnan province, south-west PR China. The 16S rRNA gene sequence analysis showed that the strain SYSU G01002T shared the highest sequence identity with the type strain of Bacillus alkalitolerans (97.7%). Strain SYSU G01002T grew at pH 6.0–8.0 (optimum, pH 7.0), at 28–55 °C (optimum, 45 °C) and in the presence of 0–2.5% (w/v) NaCl (optimum in the absence of NaCl). It contained meso-2,6-diaminopimelic acid as the cell-wall diamino acid and MK-7 as isoprenoid quinone. The major cellular fatty acids were iso-C15:0, iso-C17:0 and C16:0. The polar were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and unidentified phospholipid. The genomic DNA G + C content was 38.0 mol %. The digital DNA–DNA hybridization and average nucleotide identity values between SYSU G01002T and closely related members of the genus Bacillus were below the cut-off level recommended for interspecies identity. Based on the above results, strain SYSU G01002T represents a novel species of the genus Bacillus, for which the name Bacillus tepidiphilus sp. nov. is proposed. The type strain, SYSU G01002T (= KCTC 43131T = CGMCC 1.17491T). [ABSTRACT FROM AUTHOR]

A Gram stain-positive, rod-shaped and motile bacterium, designated SYSU G01003T was isolated from a sediment sample collected from tepid spring in Tengchong, Yunnan province, southwestern China. Growth observed at temperature ranging 28–37 °C (optimum 37 °C) and pH 6.0–8.0 (optimum pH 7.0). Tolerance to NaCl was up to 2.5% (w/v) (optimal in the absence of NaCl). The cell wall peptidoglycan is meso-2,6-diaminopimelic acid and MK-7 as the only respiratory quinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified aminophospholipid, phospholipid, and polar lipid. The major fatty acids are C16:0, anteiso-C15:0 and C14:0. The genomic DNA G + C content of the type strain was 54.0 mol%. The average nucleotide identity (ANIb and ANIm) values between SYSU G01003T and Paenibacillus azotifigens LMG 29963T were below the cut-off level (95–96%) recommended as the average nucleotide identity (ANI) criterion for interspecies identity. Based on the above results strain SYSU G01003T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus yunnanensis sp. nov. is proposed. The type strain, SYSU G01003T (=KCTC 43132T = CGMCC 1.17384T). [ABSTRACT FROM AUTHOR]

One motile strain designated, YIM DR1026T was isolated from the roots of Psammosilene tunicoides collected from Gejiu, Yunnan province, China. The cells of strain YIM DR1026T were Gram-negative and short-rod shaped. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YIM DR1026T was a member of the genus Aureimonas and closely related to Aureimonas rubiginis (96.7%). DNA–DNA relatedness values between strain YIM 1026T and Aureimonas rubiginis BCRC 80440T was 38.2 ± 1.5%. The ANI value between YIM DR1026T and other Aureimonas members were below the cut-off level (95–96%) recommended as the average nucleotide identity (ANI) criterion for interspecies identity. Strain YIM DR1026T grew at 4–30 °C (optimum 28 °C), pH 4.0–9.0 (optimum pH 6.0–7.0) and tolerated NaCl (w/v) up to 1% (optimum 0%). Q-10 was sole the respiratory ubiquinone present in YIM DR1026T. Polar lipids of strain YIM DR1026T were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, sulfoquinovosyldiacylglycerol, unidentified aminolipid and unidentified polar lipid. The genomic G + C content was 64.6 mol%. The major fatty acids were C18:1ω7c, C16:0 and summed feature 3 (C16:1ω7c/C16:1ω6c). Based on phenotypic, phylogenetic, chemotaxonomic and genome comparison, strain YIM DR1026T represents a novel species of the genus Aureimonas, for which the name Aureimonas psammosilene sp. nov. is proposed. The type strain is YIM DR1026T (= KCTC 42691T = NBRC 112412T). [ABSTRACT FROM AUTHOR]

A Gram-staining positive, motile, rod-shaped and subterminal endospore-forming bacterium, designated strain SYSU K30005T, was isolated from a soil sample collected from a karst cave in Libo county, Guizhou province, south-western China. Strain SYSU K30005T showed the highest 16S rRNA gene sequence similarity with Lysinibacillus fusiformis (98.6%) and Lysinibacillus sphaericus (98.2%). In phylogenetic tree, strain SYSU K30005T clade with the members of the genus Lysinibacillus. Based on the phylogenetic and 16S gene sequence result, strain SYSU K30005T was affiliated to the genus Lysinibacillus. The growth of SYSU K30005T was observed at 15–37 °C (optimum, 28 °C), pH 6.0–9.0 (optimum, pH 7.0) and in the presence of 0–4% (w/v) NaCl (optimum in 3.5% NaCl). Cell wall peptidoglycan type was A4α (Lys–Asp). The cell-wall sugars of SYSU K30005T were ribose, galactose and mannose and MK-7 was the only quinone. The fatty acids (> 5% of total fatty acids) were iso-C15:0, anteiso-C15:0, iso-C16:0 and iso-C17:0. The polar lipids profile included diphosphatidylglycerol, phosphatideylglycerol, phosphatidylethanolamine and an unidentified phospholipid. The genomic DNA G + C content was 37.2 mol%. The average nucleotide identity values between SYSU K30005T and its closest relatives were below the cut-off level (95–96%) for species delineation. The results support the conclusion that strain SYSU K30005T represents a novel species of the genus Lysinibacillus, for which we proposed the name Lysinibacillus cavernae sp. nov. The type strain is SYSU K30005T (= KCTC 43130T = CGMCC 1.17492T). [ABSTRACT FROM AUTHOR]

We report for the first time the isolation of endophytic actinobacteria associated with wild populations of the Chinese medicinal herb Thymus roseus Schipcz obtained from the arid land in Ili and Tacheng of the Xinjiang Province, China. Strains were isolated by special pretreatment of plant tissues and identified based on their 16S rRNA gene sequences, and their antimicrobial activities in vitro were evaluated. A total of 126 endophytic actinobacteria belonging to two classes, eight orders, 14 families, and 24 genera were isolated from different organs at the Ili and Tacheng sites. In addition, the diversity of culturable endophytic actinobacteria genera was higher at Tacheng site (n = 71, 56.35%) than the Ili site (n = 55, 43.65%). A neighbor-joining tree of 126 isolated actinobacteria showing the phylogenetic relationships based on 16S rRNA gene sequences and the genus Streptomyces was the most dominant isolate. The number of endophytic actinobacteria genera obtained from root tissues (n = 54, 42.86%) was higher compared to stem (n = 35, 27.78%) and leaf tissue (n = 37, 29.36%). Among 126 endophytic actinobacteria, 54 strains were antagonistic against at least one or more indicator organisms in vitro. Notably, most strains of Streptomyces proved antagonistic activities. For example, strain T4SB028, namely Streptomyces polyantibioticus , showed the highest inhibition ratio reached 67.06, 64.20, and 70.55% against Alternaria solani , Valsa malicola , and Valsa mali , respectively. The results demonstrate that about 30.95%, 23.01% of the tested endophytic actinobacteria were capable of producing siderophores and chitinase, respectively. Additionally, the results of the amplification of biosynthetic genes polyketide synthetase (PKS-I) and non-ribosomal peptide synthetase (NRPS) indicated that at least one antibiotic biosynthetic gene was detected in 27 (50%) of the tested strains. Our result emphasizes that the endophytic actinobacteria communities are different based on the plant tissues and the geographical environment of the sampled area. Thus, we conclude that T. roseus Schipcz. provided a rich source of endophytic actinobacteria that exhibited a broad-spectrum antimicrobial agent. [ABSTRACT FROM AUTHOR]

Two extreme halophilic archaeal strains, SYSUA9-0T and SYSUA9-1, were isolated from Ebi lake of Xinjiang, China. The colonies were Gram-negative, coccoid, and non-motile. Strains were aerobic and grew at 25–50 °C (optimum at 37 °C), in the presence of 10–35% (w/v) NaCl (optimum at 20–22%), and pH 6.0–8.0 (optimum at 7.0). The 16S rRNA gene sequence result revealed that the two strains were closely related to Haloprofundus marisrubri SB9T (92.7% similarity). The DNA–DNA hybridization value (97% ± 1%) suggested that SYSUA9-0T and SYSUA9-1 were similar; however, their sequence similarities with other archaeal members suggested that they were novel candidates. The genomic G + C content of SYSUA9-0T was 66.9%. The average nucleotide identity value between SYSU A9-0T and Haloprofundus marisrubri SB9T was 69.1%, which was far below the cutoff value (95–96%) proposed to define the species boundary. The polar lipids were phosphatidylglycerol (PG), phosphatidylglycerolphosphate methylester (PGP-Me), sulfated mannosyl glucosyl diether, mannosyl glucosyldiether, and four unidentified glycolipids. Phenotypic, chemotaxonomic and comparative genome analysis suggested that SYSU A9-0T and SYSU A9-1 represent a novel species of a new genus within the family Haloferacaceae, for which the name Halegenticoccus soli gen. nov., sp. nov., is proposed. The type strain is SYAUA9-0T (= KCTC4241T = CGMCC 1.15765T). [ABSTRACT FROM AUTHOR]

A Gram-negative bacterium, designated as strain YIM 690229T, was isolated from the roots of Limonium otolepis. The strain was able to grow at 10-40 °C (optimum, 28-37 °C), pH 6.0-8.0 (optimum, 7.0) and in the presence of up to 7% NaCl (w/v) (optimum, up to 2.5%). Comparative 16S rRNA gene sequence analysis revealed that strain YIM 690229T shared less than 93.9% sequence similarities with members within the order Rhizobiales, and was remotely related to members of the family Hyphomicrobiaceae. Strain YIM 690229T was characterized by the presence of Q-10 as the predominant respiratory lipoquinone. The major fatty acids (> 10%) detected were C18:1ω7c, C16:0, anteiso-C15:0 and summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B). The polar lipids consisted of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmethylethanoamine and two unidentified lipids. The genomic DNA G + C content was 57.2 mol%. Data from this polyphasic taxonomy study suggested that strain YIM 690229T should be classified as a new species of a new genus within the family Hyphomicrobiaceae for which the name Limoniibacter endophyticus gen. nov., sp. nov., is proposed. The type species of the genus Limoniibacter gen. nov. is Limoniibacter endophyticus. The type strain of the species Limoniibacter endophyticus sp. nov. is YIM 690229T (= KCTC 42097T = JCM 30141T = CCTCC AB 2014130T = CGMCC 1.12906T). [ABSTRACT FROM AUTHOR]

A novel actinobacterium, designated strain JXJ CY 19T, was isolated from a culture mat of Microcystis aeruginosa FACHB-905 collected from Dianchi Lake, South-west China. 16S rRNA gene sequences comparison of strain JXJ CY 19T and the available sequences in the GenBank database showed that the strain was closely related to Modestobacter marinus 42H12-1T (99.1% similarity) and Modestobacter roseus KLBMP 1279T (99.0%). The isolate had meso-diaminopimelic in the cell wall with whole-cell sugars of mannose, rhamnose, ribose, glucose, galactose, and arabinose. The menaquinone detected was MK-9(H4), while the major cellular fatty acids include C17:1 ω8c, C15:0 iso, C15:1 iso G and C16:0 iso. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The DNA-DNA hybridization values between strains JXJ CY 19T and the closely related type strains Modestobacter marinus CGMCC 4.5581T and Modestobacter roseus NBRC 108673T were determined to be 50.8 ± 0.8% and 44.1 ± 1.7%, respectively. The DNA G+C content was 71.9 mol%. On the basis of the above taxonomic data and differences in physiological characters from the closely related type strains, strain JXJ CY 19T was recognized as a novel species of the genus Modestobacter, for which the name Modestobacter lacusdianchii sp. nov. (JXJ CY 19T = KCTC 39600T = CPCC 204352T) is proposed. The type strain JXJ CY 19T can solubilize calcium phosphate tribasic (Ca3(PO4)2), phytin and L-α-phosphatidylcholine. The phosphate-solubilizing property of the novel actinobacterium could be a possible factor for the increase in growth of Microcystis aeruginosa FACHB-905 in ecosystem where the amount of available soluble phosphate is limited such as Dianchi Lake. [ABSTRACT FROM AUTHOR]

In our search for novel anaerobes with potential carbohydrate polymers degrading activity, we have isolated a xylan-degrading bacterial strain SYSU GA17129T from an anammox bacteria dominant wastewater treatment plant. Phylogenetic analysis of the 16S rRNA gene sequence indicated the strain SYSU GA17129T belong to the order Clostridiales and shared highest sequence identity with Caldicoprobacter faecalis DSM 20678T (89.9%). The strain was thermophilic, obligately anaerobic, non-motile and rod shaped. Optimum growth of the strain was observed at 45 °C, pH 8.0 and in the presence of 0.5% NaCl (w/v). The chemotaxonomic features of the strain SYSU GA17129T comprised of C 14:0 FAME, iso-C 15:0 FAME and C 16:0 FAME as the major fatty acids (>10%), diphosphatidylglycerol, phosphatidylinositol mannoside, an unidentified phospholipid, three unidentified polar lipids and two unidentified glycolipids as its polar lipids, and meso -diaminopimelic acid (meso -DAP) as the diamino acid in peptidoglycan. The G + C content of the genomic DNA was 35.9%. The strain could be distinguished from other defined families within the order Clostridiales by the differences in phenotypic and physiological characteristics, distinct phylogenetic lineage in 16S rRNA gene- and genome-based phylogenies and low genomic relatedness index. Based on these distinguishing properties, strain SYSU GA17129T is proposed to represent a new species of a new genus Xylanivirga thermophila gen. nov., sp. nov., within a new family Xylanivirgaceae fam. nov. The type species of the new taxon is SYSU GA17129T (=KCTC 15754T = CGMCC 1.5282T). This strain is characterized within the order Clostridiales , class Clostridia of the phylum Firmicutes. • A xylan-degrading bacterial strain SYSU GA17129T was isolated from a wastewater treatment plant. • 16S rRNA gene and genome-based phylogenies reveal strain SYSU GA17129T is a new member of the order Clostridiales. • The strain is thermophilic, obligately anaerobic, non-motile and rod shaped. [ABSTRACT FROM AUTHOR]