Pseudonocardia tritici sp. nov., a novel actinomycete isolated from rhizosphere soil of wheat (Triticum aestivum L.)

Actinoplanes sandaracinus sp. nov., a novel ligninase- producing and cellulose-degrading actinobacterium isolated from soil

A novel ligninase-producing and cellulose-degrading actinobacterium, designated strain NEAU-A12T, was isolated from a soil sample collected from Aohan banner, Chifeng City, Inner Mongolia Autonomous Region, PR China. A polyphasic taxonomic study was used to establish the status of strain NEAU-A12T. 16S rRNA gene sequence analysis revealed that strain NEAU-A12T belonged to the genus Actinoplanes and showed the highest similarity (98.3 %) to Actinoplanes palleronii DSM 43940T, while showing less than 98.3 % similarity to other members of the genus Actinoplanes. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and glycosylphosphatidylinositol. The diagnostic sugars in cell hydrolysates were determined to be arabinose, glucose and xylose. The cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The major fatty acids were C15 : 0, C16 : 0, C16 : 1  ω7c and C17 : 0. Meanwhile, genomic analysis revealed a genome size of 10 192 524 bp and a DNA G+C content of 70.6 mol%, and indicated that strain NEAU-A12T had the potential to degrade lignin and cellulose, as well as produce bioactive compounds. In addition, the average nucleotide identity values between strain NEAU-A12T and its reference strains A. palleronii DSM 43940T, Actinoplanes regularis DSM 43151T, Actinoplanes philippinensis DSM 43019T, Actinoplanes xinjiangensis DSM 45184T and Actinoplanes italicus DSM 43146T were 80.3, 80.3, 84.1, 84.3 and 84.0 %, respectively. The levels of digital DNA-DNA hybridization between them were found to be 23.6 % (21.3-26.1 %), 23.8 % (21.5-26.3 %), 28.3 % (25.9-30.8 %), 28.6 % (26.0-30.9 %) and 28.4 % (26.2-31.1 %), respectively. Based on phenotypic, chemotaxonomic and genotypic data, strain NEAU-A12T is considered to represent a novel species of the genus Actinoplanes, for which the name Actinoplanes sandaracinus sp. nov. is proposed, with NEAU-A12T (=CCTCC AA 2020039T=DSM 112043T) as the type strain.

Root microbiome diversity and structure of the Sonoran desert buffelgrass (Pennisetum ciliare L.)

Buffelgrass (Pennisetum ciliare) is an invasive plant introduced into Mexico's Sonoran desert for cattle grazing and has converted large areas of native thorn scrub. One of the invasion mechanisms buffelgrass uses to invade is allelopathy, which consists of the production and secretion of allelochemicals that exert adverse effects on other plants' growth. The plant microbiome also plays a vital role in establishing invasive plants and host growth and development. However, little is known about the buffelgrass root-associated bacteria and the effects of allelochemicals on the microbiome. We used 16S rRNA gene amplicon sequencing to obtain the microbiome of buffelgrass and compare it between samples treated with root exacknudates and aqueous leachates as allelochemical exposure and samples without allelopathic exposure in two different periods. The Shannon diversity values were between H' = 5.1811-5.5709, with 2,164 reported bacterial Amplicon Sequence Variants (ASVs). A total of 24 phyla were found in the buffelgrass microbiome, predominantly Actinobacteria, Proteobacteria, and Acidobacteria. At the genus level, 30 different genera comprised the buffelgrass core microbiome. Our results show that buffelgrass recruits microorganisms capable of thriving under allelochemical conditions and may be able to metabolize them (e.g., Planctomicrobium, Aurantimonas, and Tellurimicrobium). We also found that the community composition of the microbiome changes depending on the developmental state of buffelgrass (p = 0.0366; ANOSIM). These findings provide new insights into the role of the microbiome in the establishment of invasive plant species and offer potential targets for developing strategies to control buffelgrass invasion.

Description of a new strain of Streptomonospora nanhaiensis and reclassification of Streptomonospora halotolerans as a later heterotypic synonym of Streptomonospora nanhaiensis

A novel actinomycete, designated strain NEAU-YY374, was isolated from root of wheat and a polyphasic taxonomic study was carried out. 16S rRNA gene sequence analysis indicated that strain NEAU-YY374 was closely related to Streptomonospora halotolerans NEAU-Jh2-17^T (99.3 %) and Streptomonospora nanhaiensis 12A09^T (98.6%). Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strain NEAU-YY374 formed a stable clade with S. halotolerans NEAU-Jh2-17^T and S. nanhaiensis 12A09^T in trees generated with two algorithms. Key morphological and chemotaxonomic properties also confirmed the affiliation of strain NEAU-YY374 to the genus Streptomonospora. The differences of DNA G+C contents among these three strains were all less than 1 %, and the digital DNA-DNA hybridization and the average nucleotide identity values were higher than the circumscription thresholds of species and subspecies, clearly indicating that the three strains should belong to the same species. Therefore, we concluded that strain NEAU-YY374 is a new strain of S. nanhaiensis. Meanwhile, S. halotolerans should be reclassified as a later heterotypic synonym of S. nanhaiensis according to the priority of publication and validation of the name.

Inter-Kingdom Networks of Canola Microbiome Reveal Bradyrhizobium as Keystone Species and Underline the Importance of Bulk Soil in Microbial Studies to Enhance Canola Production

The subterranean microbiota of plants is of great importance for plant growth and health, as root-associated microbes can perform crucial ecological functions. As the microbial environment of roots is extremely diverse, identifying keystone microorganisms in plant roots, rhizosphere, and bulk soil is a necessary step towards understanding the network of influence within the microbial community associated with roots and enhancing its beneficial elements. To target these hot spots of microbial interaction, we used inter-kingdom network analysis on the canola growth phase of a long-term cropping system diversification experiment conducted at four locations in the Canadian Prairies. Our aims were to verify whether bacterial and fungal communities of canola roots, rhizosphere, and bulk soil are related and influenced by diversification of the crop rotation system; to determine whether there are common or specific core fungi and bacteria in the roots, rhizosphere, and bulk soil under canola grown in different environments and with different levels of cropping system diversification; and to identify hub taxa at the inter-kingdom level that could play an important ecological role in the microbiota of canola. Our results showed that fungi were influenced by crop diversification, which was not the case on bacteria. We found no core microbiota in canola roots but identified three core fungi in the rhizosphere, one core mycobiota in the bulk soil, and one core bacterium shared by the rhizosphere and bulk soil. We identified two bacterial and one fungal hub taxa in the inter-kingdom networks of the canola rhizosphere, and one bacterial and two fungal hub taxa in the bulk soil. Among these inter-kingdom hub taxa, Bradyrhizobium sp. and Mortierella sp. are particularly influential on the microbial community and the plant. To our knowledge, this is the first inter-kingdom network analysis utilized to identify hot spots of interaction in canola microbial communities.

Saccharothrix luteola sp. nov., a novel cellulose-degrading actinobacterium isolated from soil and emended description of the genus Saccharothrix

A novel cellulose-degrading actinobacterium, designated strain NEAU-S10^T, was isolated from soil collected from Chifeng, Inner Mongolia Autonomous Region, PR China, and characterized using a polyphasic approach. Pairwise similarity of the 16S rRNA gene sequence showed that strain NEAU-S10^T was a representative of Saccharothrix and was closely related to Saccharothrix carnea NEAU-yn17^T (99.2 %), Saccharothrix saharensis SA152^T (99.0 %), Saccharothrix texasensis DSM 44231^T (98.5 %) and Saccharothrix xinjiangensis NBRC 101911^T (98.5 %). Physiological and chemotaxonomic characteristics of the strain further supported its affiliation to the genus Saccharothrix. The whole-cell sugars contained galactose, ribose and mannose. The polar lipids contained diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The predominant menaquinones were MK-9(H₀), MK-9(H₂), MK-9(H₄) and MK-10(H₄). The major fatty acids were iso-C_16 : 0, C_16 : 0, anteiso-C_17 : 0, iso-C_15 : 0 and iso-C_17 : 0. The genomic DNA G+C content was 71.8 mol%. The levels of digital DNA-DNA hybridization between isolate and S. carnea NEAU-yn17^T, S. saharensis SA152^T and S. texasensis DSM 44231^T were 40.1 % (37.6-42.6 %), 38.soap8 % (36.3-41.3 %) and 44.8 % (42.2-47.3 %) and the ANI values between them were determined to be 90.2, 89.8 and 91.7 %, the results indicated that strain NEAU-S10^T could be distinguished from its reference strains. The assembled genome sequence of strain NEAU-S10^T was found to be 10 305 394 bp long. The NCBI Prokaryotic Genome Annotation Pipeline (PGAP) revealed 8 994 protein-coding genes. Genomic analysis and Congo red staining test indicated that strain NEAU-S10^T had the potential to degrade cellulose. The genomic and phenotypic results indicate that strain NEAU-S10^T represents a novel species of the genus Saccharothrix, for which the name Saccharothrix luteola sp. nov. is proposed, with NEAU-S10^T (=CCTCC AA 2020037^T=JCM 34800^T) as the type strain.

Sustainable bioremediation approach to treat the sago industry effluents and evaluate the possibility of yielded biomass as a single cell protein (SCP) using cyanide tolerant Streptomyces tritici D5

This sustainable approach was performed to evaluate the bioremediation potential of cyanide resistant bacterial species on sago industry effluents and assess the possibility of using the yielded biomass as single cell protein (SCP). The predominant cyanide tolerant bacterium enumerated from muddy soil was identified as Streptomyces tritici D5 through 16S rRNA sequencing. The identified S. tritici D5 strains showed excellent resistant and degradation potential at 100 mM concentration of potassium cyanide. Furthermore, the physicochemical properties analysis of sago industry effluents results revealed that the most of the parameters were crossing the permissible limits of Pollution control board of India. The bioremediation process was performed at various temperatures at 25 °C, 35 °C, and 45 °C for a period of 30 days of continuous bioremediation process with the aid of an aerator. Surprisingly, the best organic pollutant reduction was found at 35 °C and 45 °C, with 25 °C following close behind. Remarkably, the dissolved oxygen (DO) level was gradually increased from 2.24 to 12.04 mg L^-1 at 35 °C in 30 days of the remediation process. The pH and ammonia were also significantly increased during the bioremediation process in 30 days of treatment. Similarly, at 35 °C of bioremediation process the S. tritici D5 yielded maximum dried biomass (6.9 g L^-1) with the total crude protein (SCP) as 4.8 g L^-1 (69.56%) in 30 days of growth. These findings stated that S. tritici D5 can treat sago industry effluents and that the biomass produced may be considered SCP after some in-vitro and in-vivo analyses.

Use of soil actinomycetes for pharmaceutical, food, agricultural, and environmental purposes

In this article, we reviewed the international scientific production of the last years on actinomycetes isolated from soil aiming to report recent advances in using these microorganisms for different applications. The most promising genera, isolation conditions and procedures, pH, temperature, and NaCl tolerance of these bacteria were reported. Based on the content analysis of the articles, most studies have focused on the isolation and taxonomic description of new species of actinomycetes. Regarding the applications, the antimicrobial potential (antibacterial and antifungal) prevailed among the articles, followed by the production of enzymes (cellulases and chitinases, etc.), agricultural uses (plant growth promotion and phytopathogen control), bioremediation (organic and inorganic contaminants), among others. Furthermore, a wide range of growth capacity was verified, including temperatures from 4 to 60 °C (optimum: 28 °C), pH from 3 to 13 (optimum: 7), and NaCl tolerance up to 32% (optimum: 0-1%), which evidence a great tolerance for actinomycetes cultivation. Streptomyces was the genus with the highest incidence among the soil actinomycetes and the most exploited for different uses. Besides, the interest in isolating actinomycetes from soils in extreme environments (Antarctica and deserts, for example) is growing to explore the adaptive capacities of new strains and the secondary metabolites produced by these microorganisms for different industrial interests, especially for pharmaceutical, food, agricultural, and environmental purposes.

Nocardia rosealba sp. nov., a novel ligninase-producing Actinobacterium isolated from soil

A novel ligninase-producing actinomycete, designated strain NEAU-G4T, was isolated from a soil sample and subjected to a polyphasic taxonomic study to establish its status. According to 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Nocardia , with the highest sequence similarity to Nocardia ignorata DSM 44496T (99.2 %). The whole-cell sugars contained galactose and arabinose. The amino acid of the cell wall was determined to be meso-diaminopimelic acid. The major fatty acids (>10 %) were C16 : 0, C18 : 1  ω9c, C18 : 0 and C16 : 1  ω7c. The predominant menaquinone was identified as MK-8(H6, ω-cycl). The major polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Strain NEAU-G4T had a draft genome size of 6 405 167 bp, annotated with 5815 protein-coding genes. The DNA G+C content was 67.6 mol%. Phylogenetic analysis using the 16S rRNA gene and whole-genome sequences showed that strain NEAU-G4T formed a stable phyletic line with N. ignorata DSM 44496T. The digital DNA–DNA hybridization and average nucleotide identity values between them were 63.7 % (60.8–66.5 %) and 95.5 %, respectively. Moreover, genomic analysis indicated that strain NEAU-G4T had the potential to degrade lignin and produce bioactive compounds. On the basis of genotypic analysis, physiological data, as well as phenotypic and chemotaxonomic characterizations, it is concluded that the organism be classified as representing a novel species of the genus Nocardia , for which the name Nocardia rosealba sp. nov. is proposed. The type strain is NEAU-G4T (=CCTCC AA 2020038T=DSM 111936T).

Catellatospora tritici sp. nov., a novel cellulase-producing actinobacterium isolated from rhizosphere soil of wheat (Triticum aestivum L.) and emended description of the genus Catellatospora

A Gram-positive, cellulose-degrading actinobacterium, designed strain NEAU-YM18T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) sampled in Langfang, Hebei Province, PR China. The novel strain was characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics confirmed that strain NEAU-YM18T belonged to the genus Catellatospora . Cells of strain NEAU-YM18T were observed to contain meso- and 3-hydroxy-diaminopimelic acids as diagnostic cell-wall amino acids. The acyl type of the cell-wall muramic acid was glycolyl. The whole-cell hydrolysates were xylose, glucose and ribose. The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were iso-C15 : 0, iso-C16 : 0, C18 : 1  ω9c and summed feature 5 (anteiso-C18 : 0/C18 : 2  ω6,9c). The menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The DNA G+C content was 71.1 %. The results of 16S rRNA gene sequence and phylogenetic analyses indicated that strain NEAU-YM18T was closely related to Catellatospora chokoriensis 2-25(1)T (98.4 % 16S rRNA gene sequence similarity), Catellatospora vulcania NEAU-JM1T (98.3%) and Catellatospora sichuanensis H14505T (98.3 %) and formed a branch with C. sichuanensis H14505T. Furthermore, the whole genome phylogeny of strain NEAU-YM18T showed that the strain formed an independent clade. The digital DNA–DNA hybridization results between NEAU-YM18T and C. chokoriensis 2-25(1)T, C. vulcania NEAU-JM1T and C. sichuanensis H14505T were 25.0, 24.7 and 24.7 %, respectively, and the whole-genome average nucleotide identity values between them were 81.5, 81.4 and 81.4 %, respectively. These genetic results and some phenotypic characteristics could distinguish strain NEAU-YM18T from its reference strains. In addition, genomic analysis confirmed that strain NEAU-YM18T had the potential to decompose cellulose and produce bioactive compounds. Therefore, strain NEAU-YM18T represents a novel species of the genus Catellatospora , for which the name Catellatospora tritici sp. nov. is proposed. The type strain is NEAU-YM18T (=CCTCC AA 2020040T=JCM 33977T).

16S rDNA analysis of osteoporotic rats treated with osteoking

Introduction. Osteoporosis (OP) is characterized by microstructural degeneration of bone tissue, low bone mass, bone fragility and even brittle fracture (osteoporotic fracture, OPF). OP and OPF are common and there are many disadvantages to the current medications for OP/OPF. Osteoking is a traditional Chinese medicine (TCM) originating from the Yi nationality (Yunnan, China) that has been used to treat bone diseases for decades.Hypothesis/Gap Statement. This study will reveal the changes in the intestinal microbiota of OP rats after 70 days of osteoking treatment.Method. With duplication of sham and OP rats, eight groups were established, with six rats in each group. The intestinal microbiotas were analysed by 16S rDNA sequencing.Results. The results showed that osteoking changed the intestinal microbiota of sham rats and OP rats. The mechanism by which osteoking improves OP is related to the functions of the intestinal microbiota. After 70 days of treatment with osteoking, the contents of Pseudonocardia, Pedomicrobium, Variovorax, Niastella and Actinosynnema were decreased in OP rats. The functions of the above intestinal microbiota related to iron metabolism affected calcifediol and 25(OH)D, and measuring these bone metabolic indicators is required for further study.Conclusion. Osteoking changes the intestinal microbiota to improve OP, and further study which reveals these intestinal microbiota and mechanism is needed.

Streptomyces botrytidirepellens sp. nov., a novel actinomycete with antifungal activity against Botrytis cinerea

The fungal pathogen Botrytis cinerea is the causal agent of devastating gray mold diseases in many economically important fruits, vegetables, and flowers, leading to serious economic losses worldwide. In this study, a novel actinomycete NEAU-LD23^T exhibiting antifungal activity against B. cinerea was isolated, and its taxonomic position was evaluated using a polyphasic approach. Based on the genotypic, phenotypic and chemotaxonomic data, it is concluded that the strain represents a novel species within the genus Streptomyces, for which the name Streptomyces botrytidirepellens sp. nov. is proposed. The type strain is NEAU-LD23^T (=CCTCC AA 2019029^T=DSM 109824^T). In addition, strain NEAU-LD23^T showed a strong antagonistic effect against B. cinerea (82.6±2.5%) and varying degrees of inhibition on nine other phytopathogenic fungi. Both cell-free filtrate and methanol extract of mycelia of strain NEAU-LD23^T significantly inhibited mycelial growth of B. cinerea. To preliminarily explore the antifungal mechanisms, the genome of strain NEAU-LD23^T was sequenced and analyzed. AntiSMASH analysis led to the identification of several gene clusters responsible for the biosynthesis of bioactive secondary metabolites with antifungal activity, including 9-methylstreptimidone, echosides, anisomycin, coelichelin and desferrioxamine B. Overall, this research provided us an excellent strain with considerable potential to use for biological control of tomato gray mold.

Actinoplanes flavus sp. nov., a novel cellulase-producing actinobacterium isolated from coconut palm rhizosphere soil

A novel cellulase-producing actinomycete, designated strain NEAU-H7^T, was isolated from coconut palm rhizosphere soil collected from Wenchang City, Hainan Province, PR China. A polyphasic taxonomic study was carried out to establish the status of this strain. Results of 16S rRNA gene sequence analysis indicated that strain NEAU-H7^T belonged to the genus Actinoplanes, with highest similarity to Actinoplanes hulinensis NEAU-M9^T (99.2 % 16S rRNA gene sequence similarity). The diagnostic sugars in cell hydrolysates were determined to be ribose, galactose and mannose. The major fatty acids (>10%) were C_16 : 0, C_18 : 1  ω9c and C_18 : 0. The predominant menaquinones were identified as MK-9(H₄) and MK-9(H₆). The major polar lipids were phosphatidylethanolamine, phosphatidylinositol and two phosphatidylinositol mannosides. The amino acid of the cell-wall peptidoglycan was determined to be meso-diaminopimelic acid. The DNA G+C content was 71.2 mol%. Phylogenetic analysis using 16S rRNA gene sequences showed that strain NEAU-H7^T formed a stable phyletic line with A. hulinensis NEAU-M9^T. However, whole-genome phylogeny showed strain NEAU-H7^T formed a stable phyletic line with A. hulinensis NEAU-M9^T (99.2%), Actinoplanes campanulatus DSM 43148^T (98.6%), Actinoplanes capillaceus DSM 44859^T (98.3%) and Actinoplanes lobatus DSM 43150^T (97.6%). The digital DNA-DNA hybridization (dDDH) results between them were 53.6 (50.9-56.2), 54.1 (51.3-56.9), 53.1 (50.3-55.9) and 52.9 % (50.1-55.6 %), and whole-genome average nucleotide identity (ANI) values between them were 93.7, 93.6, 93.5 and 93.5 %. The low dDDH and ANI values demonstrated that strain NEAU-H7^T could be distinguished from its reference strains. Moreover, genomic analysis indicated that the strain NEAU-H7^T had the potential to decompose cellulose and produce bioactive compounds. On the basis of morphological, chemotaxonomic and phylogenetic characteristics, strain NEAU-H7^T is proposed to represent a novel species of the genus Actinoplanes, with the name Actinoplanes flavus sp. nov. The type strain is NEAU-H7^T (=CCTCC AA 2020034^T=DSM 112042^T).

Actinoplanes aureus sp. nov., a novel protease-producing actinobacterium isolated from soil

A novel protease-producing actinobacterium, designated strain NEAU-A11^T, was isolated from soil collected from Aohan banner, Chifeng, Inner Mongolia Autonomous Region, China, and characterised using a polyphasic approach. The hydrolytic enzymes, such as proteases, played critical roles in destruction of fungi by degrading the protein linkages to disrupt integrity in the cell wall. This suggested that the isolate could be a good biocontrol candidate against pathogens to control fungal diseases. On the basis of 16S rRNA gene sequence analysis, strain NEAU-A11^T was indicated to belong to the genus Actinoplanes and was most closely related to Actinoplanes rectilineatus JCM 3194 ^T (98.9%). Cell walls contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were arabinose, xylose and glucose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and two phosphatidylinositol mannosides. The predominant menaquinones were MK-9(H₄), MK-9(H₆) and MK-9(H₈). The major fatty acids were C_18:0, C_16:0, C_18:1 ω9c, C_17:0 and C_15:0. Genome sequencing revealed a genome size of 10,742,096 bp, a G + C content of 70.5% and 9,514 protein-coding genes (CDS), including 102 genes coding for protease. Moreover, Genome analysis showed that strain NEAU-A11^T contained 255 glycoside hydrolases (GHs), 152 glycosyl transferases (GTs), 40 carbohydrate esterases (CEs), 26 polysaccharide lyases (PLs), and 12 auxiliary activities (AAs) genes. Genome mining analysis using antiSMASH 5.0 led to the identification of 20 putative gene clusters responsible for the production of diverse secondary metabolites. Phylogenetic analysis using the 16S rRNA gene sequences showed that the strain formed a stable clade with A. rectilineatus JCM 3194 ^T in the genus Actinoplanes. Whole-genome phylogeny showed strain NEAU-A11^T formed a stable phyletic line with Actinoplanes lutulentus DSM 45883 ^T (97.6%). However, whole-genome average nucleotide identity value between strain NEAU-A11^T and its reference strains A. rectilineatus JCM 3194 ^T and A. lutulentus DSM 45883 ^T were found to be 81.1% and 81.6%, respectively. The levels of digital DNA-DNA hybridization between them were 24.6% (22.2-27.0%) and 24.8% (22.5-27.3%), respectively. The values were well below the criteria for species delineation of 70% for dDDH and 95-96% for ANI, suggesting that the isolate differed genetically from its closely related type strain. The content of G + C in genomic DNA was 70.5%, within the range of 67-76%. In addition, evidences from phenotypic, chemotaxonomic and genotypic studies indicated that strain NEAU-A11^T represents a novel species of the genus Actinoplanes, for which the name Actinoplanes aureus sp. nov. is proposed, with NEAU-A11^T (= CCTCC AA 2019063 ^T = JCM 33971 ^T) as the type strain.

Lentzea alba sp. nov., a novel actinobacterium isolated from soil

A novel actinobacterium, designated strain NEAU-D13^T, was isolated from soil collected from Aohan Banner, Chifeng, Inner Mongolia Autonomous Region, China and characterized using a polyphasic approach. On the basis of 16S rRNA gene sequence analysis, strain NEAU-D13^T belonged to the genus Lentzea and shared the highest sequence similarity with Lentzea kentuckyensisJCM 14913^T (99.17 %). Morphological and chemotaxonomic characteristics of the strain also supported its assignment to the genus Lentzea. Cell walls contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were ribose and mannose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine and phosphatidylinositol. The menaquinone was only MK-9(H₄). The major fatty acids were iso-C_16:0, C_16:0, anteiso-C_17:0, iso-C_15:0 and anteiso-C_15:0. DNA G+C content was 68.71 mol%. Phylogenetic analysis using the 16S rRNA gene sequences showed that the strain formed a stable clade with L. kentuckyensisJCM 14913^T in the genus Lentzea. Meanwhile, a combination of digital DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-D13^T could be distinguished from its closely related strain. Therefore, it is concluded that strain NEAU-D13^T represents a novel species of the genus Lentzea, for which the name Lentzea alba sp. nov. is proposed, with NEAU-D13^T (=CCTCC AA 2019089^T=JCM 33970^T) as the type strain.

Micromonospora rubida sp. nov., a novel actinobacterium isolated from soil of Harbin

A novel actinobacterium, designated strain NEAU-HG-1^T, was isolated from soil collected from Harbin, Heilongjiang Province, Northeast China and characterised using a polyphasic approach. On the basis of 16S rRNA gene sequence analysis, strain NEAU-HG-1^T belonged to the genus Micromonospora, and shared high sequence similarities with Micromonospora auratinigra DSM 44815^T (98.9%) and Micromonospora coerulea DSM 43143^T (98.7%). Morphological and chemotaxonomic characteristics of the strain also supported its assignment to the genus Micromonospora. Cell wall contained meso-diaminopimelic acid and the whole-cell sugars were arabinose and xylose. The polar lipid contained diphosphatidylglycerol, phosphatidylethanolamine, glycolipid and phosphatidylinositol. The predominant menaquinones were MK-10(H₂), MK-10(H₄) and MK-10(H₆). The major fatty acids were C_17:0 cycle, iso-C_15:0, and iso-C_16:0. Furthermore, strain NEAU-HG-1^T displayed a DNA-DNA relatedness of 33.8 ± 2.2% with M. coerulea DSM 43143^T. The level of digital DNA-DNA hybridization between strain NEAU-HG-1^T and M. auratinigra DSM 44815^T was 27.2% (24.8-29.7%). The value was well below the criteria for species delineation of 70% for dDDH. Whole-genome average nucleotide identity analyses result also indicated that the isolate should be assigned to a new species under the genus Micromonospora. Therefore, it is concluded that strain NEAU-HG-1^T represents a novel species of the genus Micromonospora, for which the name Micromonospora rubida sp. nov. is proposed, with NEAU-HG-1^T (= CGMCC 4.7479^T = JCM 32386^T) as the type strain.