Description of Sphingomonas mesophila sp. nov., isolated from Gastrodia elata Blume

Decrease in beneficial bacteria and increase in harmful bacteria in Gastrodia seedlings and their surrounding soil are mainly responsible for degradation of Gastrodia asexual propagation

Introduction

Asexual reproduction of Gastrodia elata Bl. f. glauca S. chow (GeB) produces degeneration with increasing number of GeB. Therefore, we analyzed the microorganisms of GeB seedlings and surrounding soil by Illumina Miseq high-throughput sequencing technology.

Methods

In this study, Illumina Miseq high-throughput sequencing technology was applied to analyze the types and quantities of GeB seedlings and surrounding soil microorganisms in the first to third generations of asexual reproduction, isolated and identified the dominant strains of GeB in the first to third generations and screened the antagonistic bacteria of its pathogenic fungi, and evaluated the effects of beneficial bacteria on the production performance of seedlings planted with GeB.

Results

With an increase in the number of asexual reproductive generations, the number of pathogenic fungi and bacteria in GeB seedlings and the surrounding soil increased, and the number of beneficial fungi and bacteria decreased. Pseudomonas sp., Agrobacterium rhizomes, and Herbaspirillum hiltneri were isolated and identified in the first generation, and Trichoderma harzianum, Penicillium viridiatum, Fusarium oxysporum, and Novosphingobium sp. Were isolated and identified in the third generation. Antagonistic strains of the three pathogenic bacterial strains were screened. In conclusion, beneficial bacteria significantly improved the production performance of asexual reproductive seedlings planted with GeB.

Discussion

In conclusion, our findings suggested that the microorganisms of GeB seedlings and the surrounding soil change as the number of generations of GeB reproduction increases, disrupts the microecological balance of surrounding soil and endophytic microbiomes.This study provides a theoretical basis for the degradation of asexual reproduction in GeB.

Isolation and Characterization of Sphingomonas telluris, Sphingomonas caseinilyticus Isolated from Wet Land Soil

Two novel bacterial strains, designated as SM33^T and NSE70-1^T, were isolated from wet soil in South Korea. To get the taxonomic positions, the strains were characterized. The genomic information (both 16S rRNA gene and draft genome sequence analysis) show that both novel isolates (SM33^T and NSE70-1^T) belong to the genus Sphingomonas. SM33^T share the highest 16s rRNA gene similarity (98.2%) with Sphingomonas sediminicola Dae20^T. In addition, NSE70-1^T show 96.4% 16s rRNA gene similarity with Sphingomonas flava THG-MM5^T. The draft genome of strains SM33^T and NSE70-1^T consist of a circular chromosome of 3,033,485 and 2,778,408 base pairs with DNA G+C content of 63.9, and 62.5%, respectively. Strains SM33^T and NSE70-1^T possessed the ubiquinone Q-10 as the major quinone, and a fatty acid profile with C_16:0, C_18:1 2-OH_, C_16:1 ω7c/C_16:1 ω6c (summed feature 3) and C_18:1 ω7c/C_18:1 ω6c (summed feature 8) as major fatty acids. The major polar lipids of SM33^T and NSE70-1^T were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid and phosphatidylcholine, respectively. Moreover, genomic, physiological, and biochemical results allowed the phenotypic and genotypic differentiation of strains SM33^T and NSE70-1^T from their closest and other species of the genus Sphingomonas with validly published names. Therefore, the SM33^T and NSE70-1^T represent novel species of the genus Sphingomonas, for which the name Sphingomonas telluris sp. nov. (type strain SM33^T = KACC 22222^T = LMG 32193^T), and Sphingomonas caseinilyticus (type strain NSE70-1^T = KACC 22411^T = LMG 32495^T).

Characterization of four novel bacterial species of the genus Sphingomonas, Sphingomonas anseongensis, Sphingomonas alba, Sphingomonas brevis and Sphingomonas hankyongi sp.nov., isolated from wet land

Four novel bacterial strains, designated as RG327^T, SE158^T, RB56-2^T and SE220^T, were isolated from wet soil in the Republic of Korea. To determine their taxonomic positions, the strains were fully characterized. On the basis of genomic information (16S rRNA gene and draft genome sequences), all four isolates represent members of the genus Sphingomonas. The draft genomes of RG327^T, SE158^T, RB56-2^T and SE220^T consisted of circular chromosomes of 2 226 119, 2 507 338, 2 593 639 and 2 548 888 base pairs with DNA G+C contents of 64.6, 63.6, 63.0 and 63.1 %, respectively. All the isolates contained ubiquinone Q-10 as the predominant quinone compound and a fatty acid profile with C_16 : 0, C_17 : 1ω6c, C_18 : 1 2-OH_, summed feature 3 (C_16 : 1ω7c/C_16 : 1ω6c) and summed feature 8 (C_18 : 1ω7c/C_18 : 1ω6c) as the major fatty acids, supporting the affiliation of strains RG327^T, SE158^T, RB56-2^T and SE220^T to the genus Sphingomonas. The major identified polar lipids in all four novel isolates were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid and phosphatidylcholine. Moreover, the physiological, biochemical results and low level of DNA-DNA relatedness and average nucleotide identity values allowed the phenotypic and genotypic differentiation of RG327^T, SE158^T, RB56-2^T and SE220^T from other species of the genus Sphingomonas with validly published names and indicated that they represented novel species of the genus Sphingomonas, for which the names Sphingomonas anseongensis sp. nov. (RG327^T = KACC 22409^T = LMG 32497^T), Sphingomonas alba sp. nov. (SE158^T = KACC 224408^T = LMG 324498^T), Sphingomonas brevis (RB56-2^T = KACC 22410^T = LMG 32496^T) and Sphingomonas hankyongi sp. nov., (SE220^T = KACC 22406^T = LMG 32499^T) are proposed.

Sphingomonas suaedae sp. nov., a chitin-degrading strain isolated from rhizosphere soil of Suaeda salsa

A Gram-stain-negative, aerobic, chitin-degrading, motile bacterial strain with a single polar flagellum, designated XS-10T, was isolated from saline soil sampled from the rhizosphere of Suaeda salsa, Tumd Right Banner, Inner Mongolia, PR China. Strain XS-10T grew at 10–40 °C (optimum, 35 °C), pH 5.0–9.0 (optimum, pH 8.0) and 0–12.5% NaCl (optimum 2.0 %). The phylogenetic analysis based on both the 16S rRNA gene and the phylogenomic tree revealed that strain XS-10T formed a clade with Sphingomonas turrisvirgatae MCT13T and Sphingomonas koreensis JSS-26T, sharing 98.4 and 97.5 % 16S rRNA gene similarities to S. koreensis JSS-26T and S. turrisvirgatae MCT13T, respectively. Spermidine and Q-10 were the major polyamine and the major respiratory quinone, respectively. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, two unidentified lipids and an unidentified aminophospholipid. The major fatty acids were summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c), C16 : 0 and C17 : 1  ω6c. The genome of strain XS-10T consisted of a 4 154 291 bp chromosome with a DNA G+C content of 65.5 mol%. The average nucleotide identity, average amino acid identity and digital DNA–DNA hybridization values of strain XS-10T with S. turrisvirgatae MCT13T and S. koreensis JSS-26T were 77.8 and 78.6 %, 75.9 and 76.3 %, and 22.0 and 22.9 %, respectively. Based on the phylogenetic, phenotypic, and genotypic characteristics, strain XS-10T is considered to represent a novel species of the genus Sphingomonas , for which the name Sphingomonas suaedae sp. nov. is proposed. The type strain is XS-10T (=CGMCC 1.17078T=JCM 33850T).

Cellulomonas endophytica sp. nov., isolated from Gastrodia elata Blume

A Gram-stain-positive, facultatively anaerobic and non-motile strain, designated SYSUP0004^T, was isolated from the tubers of Gastrodia elata Blume collected from Yunnan Province, PR China. The 16S rRNA gene sequence result showed that the strain SYSUP0004^T shared low similarity (97.7 %) with the type strain of Cellulomonas marina. SYSUP0004^T grew at pH 6.0-9.0 (optimum, pH 8.0), temperature 4-30 °C (optimum, 28 °C) and could tolerate NaCl up to 4 % w/v (optimum in the absence of NaCl). The cell-wall peptidoglycan type was A4β with an interpeptide bridge l-ornithine-d-glutamic acid. Cell-wall sugars were mannose, ribose, glucose, galactose and fucose. The menaquinone was MK-9(H₄). The major fatty acids were anteiso-C_15:0, anteiso-C_15 : 1 A, C_16 : 0 and anteiso-C_17 : 0. The polar lipids of SYSUP0004^T were diphosphatidylglycerol, unidentified phosphoglycolipid, phosphatidylinositol mannosides and unidentified glycolipid. The genomic DNA G+C content was 76.5 %. The average nucleotide identity values between SYSUP0004^T and members of the genus Cellulomonas were below the cut-off level (95-96 %) recommended as the ANI criterion for interspecies identity. Thus, based on the above results strain SYSUP0004^T represents a novel species of the genus Cellulomonas, for which the name Cellulomonas endophytica sp. nov. is proposed. The type strain, SYSUP0004^T (=KCTC 49025^T=CGMCC 1.16405^T).

Amycolatopsis alkalitolerans sp. nov., isolated from Gastrodia elata Blume

A Gram-staining positive and nonmotile strain designated SYSUP0005^T was isolated from tubers of Gastrodia elata Blume. The 16S rRNA gene sequence result showed that strain SYSUP0005^T shared highest sequence similarity with the type strain of Amycolatopsis cappadoca (95.7%), Amycolatopsis taiwanensis (95.4%), Amycolatopsis pigmentata (95.4%), Amycolatopsis ruanii (95.1%), and Amycolatopsis helveola (94.8%). Growth occurs at 14-37 °C (optimum temperature, 28 °C), at pH 6-9 (optimum, pH 8) and in the presence of up to 6% (w/v) NaCl. Strain SYSUP0005^T had meso-diaminopimelic acid in its peptidoglycan. The whole cell sugars were galactose, ribose, and xylose. The predominant menaquinone was MK-9(H₄) and minor menaquinones were MK-9(H₂) and MK-9(H₈). The polar lipids were diphosphatidylglycerol (DPG); phosphatidylmonomethylethanolamine (PME), phosphatidylethanolamine (PE), phosphatidylinositol (PI), unidentified glycolipid (GL), and unidentified phospholipid (PL). The genomic DNA G + C content was 69.6 mol%. The major fatty acids were iso-C_16:0, anteiso-C_17:0, C_16:0, iso-C_14:0, C_17:1 ω6c, C_17:0, and Summed Feature 3 (C_16:1 ω7c/C_16:1 ω6c). On the basis of the phenotypic, phylogenetic, chemotaxonomic characters, and genomic comparison, SYSUP0005^T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis alkalitolerans sp. nov. is proposed. The type strain is SYSUP0005^T (=KCTC 49024^T = CGMCC4.7463^T).