Antifungal activity and mechanism of oxanthromicin against Verticillium dahliae.

Oxanthromicin is an anthranone-type natural product isolated from Streptomyces sp. TRM 15522, which exhibits antifungal activity. However, the underlying mechanisms remain unclear. This study, therefore, aimed at investigating the mode of action of oxanthromicin against the phytopathogen Verticillium dahliae. We found that oxanthromicin substantially suppressed spore germination and mycelial growth in V. dahliae. Further, electron microscopy and staining with propidium iodide and Rhodamine 123 indicated that oxanthromicin causes cell membrane damage and induces changes in mitochondrial membrane potential. These findings suggest that oxanthromicin exhibits its antifungal activity by damaging fungal cell membranes. This discovery could potentially facilitate the development of oxanthromicin as a biological pesticide.

Myceligenerans pegani sp. nov., an endophytic actinomycete isolated from Peganum harmala L. in Xinjiang, PR China.

An endophytic actinomycete designated TRM65318T, was isolated from the root of Peganum harmala L. Its taxonomic status was determined using a polyphasic approach. Comparative 16S rRNA gene sequence analysis indicated that strain TRM65318T is phylogenetically most closely related to Myceligenerans salitolerans XHU 5031T (98.15 %) and Myceligenerans xiligouense DSM 15700T (97.78 %). The peptidoglycan belonged to type A4α. The polar lipids were phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, two unknown lipids and three glycolipids. The predominant menaquinones were MK-9(H4) and MK-9(H6) and the whole-cell sugars contained glucose, mannose and galactose. Major fatty acids were anteiso-C15 : 0, iso-C15 : 0 and C16 : 0. Strain TRM65318T had a genome size of 5881012 bp with a genome G+C content of 71.79 mol%. The average nucleotide identity and DNA-DNA hybridization values between strain TRM65318T and the most closely related species were much lower than the thresholds commonly used to define species. At the same time, differences in phenotypic and genotypic data showed that strain TRM65318T could be clearly distinguished from M. salitolerans XHU 5031T. Therefore, it is concluded that strain TRM65318T represents a novel species of the genus of Myceligenerans. The proposed name for this organism is Myceligenerans pegani sp. nov., with type strain TRM65318T (=CCTCC AA 2019057T=LMG 31679T).

Three novel Actinoplanes species isolated by using polyaspartic acid as a water-retaining agent for the enrichment in situ.

Three novel actinomycete strains, designated TRM66264-DLMT, TRM88002T and TRM88003T, were isolated by using polyaspartic acid as a water-retaining agent for the enrichment in situ. The 16S rRNA gene sequence and phylogenetic analyses of three strains indicated that they belonged to the genus Actinoplanes. The phylogenetically closest strains of TRM66264-DLMT, TRM88002T and TRM88003T were Actinoplanes bogorensis LIPI11-2-Ac043T (98.4 %), Actinoplanes abujensis A4029T (98.0 %) and Actinoplanes ferrugineus IFO15555T (98.1 %), respectively. The major polar lipids of strains TRM66264-DLMT and TRM88002T were phosphatidylethanolamine and disphosphatidylglycerol, while strain TRM88003T only had phosphatidylethanolamine. The predominant menaquinones of strain TRM66264-DLMT were identified as MK-9(H4) and MK-9 (H6). Strains TRM88002T and TRM88003T had MK-9(H4). The cell-wall peptidoglycan of three strains contained meso-diaminopimelic acid. The whole-cell sugars of strain TRM66264-DLMT were identified as arabinose, glucose, galactose and xylose. Strains TRM88002T and TRM88003T mainly had arabinose and glucose. The DNA G+C content of strains TRM66264-DLMT, TRM88002T and TRM88003T were 70.48, 70.46 and 70.64 mol%, respectively. Genotypic and phenotypic analysis confirmed that all three strains sre new members of the genus Acinoplanes. Therefore, it is proposed that strains TRM66264-DLMT, TRM88002T and TRM88003T represent three novel species of the genus Actinoplanes, for which the names Actinoplanes polyasparticus sp. nov. (type strain TRM66264-DLMT=CCTCC AA 2021015T=LMG 32389T), Actinoplanes hotanensis sp. nov. (type strain TRM88002T=CCTCC AA 2021036T=LMG 32621T) and Actinoplanes aksuensis sp. nov. (type strain TRM88003T=CCTCC AA 2021037 T=LMG 32622T) are proposed.

Application of Sophora alopecuroides organic fertilizer changes the rhizosphere microbial community structure of melon plants and increases the fruit sugar content.

BACKGROUND: Sophora alopecuroides L. is a leguminous plant commonly found in northwest China. In Xinjiang, the fresh herb of S. alopecuroides is often applied as a green fertilizer to the rhizosphere of melon (Cucumis melo) plants at the end of their flowering period, to improve the taste of the fruits. However, the effects of S. alopecuroides-based fertilizers on the microbial community structure of soil and crop-root systems are unclear. In order to study the sweetening mechanism of the S. alopecuroides organic fertilizer, three different varieties of melon were selected. The untreated plants were used as the control (CK) group, and the plants treated with S. alopecuroides-based organic fertilizer were selected as the treatment (T) group. The physical and chemical properties, enzyme activities and microbial community structure of the rhizosphere samples were also determined, and a correlation analysis with the fruit sweetness index was conducted. RESULTS: Sugar content of group T was at least 40% higher than that of group CK. The increase in fruit sugar content positively correlated with the increase in the abundance of beneficial microorganisms, including Pseudomonas, Bacillus, Mycobacterium, Burkholderia, Streptomyces, Acinetobacter, Proteobacteria, Lysobacter, Actinomycetes, Penicillium and Aspergillus. CONCLUSION: Sophora alopecuroides organic fertilizer could alter the composition and function of bacterial and fungal communities and promote the growth of beneficial bacteria in the melon plant rhizosphere. Further, it could increase the content of soluble solids and sugar in the fruits to achieve a sweetening effect. This fertilizer can be applied as a fruit sweetener in melon cultivation, improving the sugar content of the fruit and consequently the sweetness. © 2022 Society of Chemical Industry.

Rhizobium alarense sp. nov. and Rhizobium halophilum sp. nov. isolated from the nodule and rhizosphere of Lotus japonicus.

Two strains (TRM95111T and TRM95001T) of Gram-stain-negative, aerobic, rod-shaped microbes were isolated from the nodule and rhizosphere of Lotus japonicus grown in the campus of Tarim University in Alar, Xinjiang, China. Strain TRM95111T and strain TRM95001T shared 93.1% 16S rRNA gene sequences similarity with each other and had 98.2 and 97.9% 16S rRNA gene sequence similarity to the closest species Rhizobium subbaraois JC85T and R. halotolerans AB21T by EzBioCloud blast, respectively. Phylogenetic analyses based on 16S rRNA gene sequences, housekeeping gene sequences and core-proteome average amino acid identity (cpAAI) showed that two strains belonged to the genus Rhizobium. The value of digital DNA-DNA hybridization (dDDH) between strain TRM95111T and the closest strain R. subbaraonis JC85T was 21.8%, respectively. The dDDH value between strain TRM95001T and the closest strains R. tarimense PL-41T was 27.1%. Whole-genome average nucleotide identity (ANI) values of the strain TRM95111T were 75.6-79.3% and strain TRM95001T were 79.2-83.8%, compared to their closely related strains. The G + C content values of strain TRM95111T and TRM95001T were 65.1 and 60.7 mol%, respectively. Two isolates contained predominant quinone of Q-10 and the major fatty acids was C18:1ω7c and they were sensitive to 1 µg of amikacin and kanamycin. The polar lipids of strain TRM95111T included unidentified aminophospho lipids (APL1-3), unidentified phospholipids (PL1-2), phosphatidylcholine (PC), unidentified lipids (L1-5) and phospholipids of unknown structure containing glucosamine (NPG), compared to the polar lipids of strain TRM95001T including unidentified aminophospho lipids (APL1-3), unidentified phospholipids (PL1-2), phosphatidylcholine (PC), unidentified lipids (L2-5), hydroxy phosphatidyl ethanolamine (OH-PE) and phospholipids of unknown structure containing glucosamine (NPG). Nodulation tests showed that two strains could induce nodules formation in L. japonicus. Based on the genomic, phenotypic and phylogenetic analyses, strain TRM95111T and strain TRM95001T are suggested to represent two new species of the genus Rhizobium, whose names are proposed as Rhizobium alarense sp. nov. and Rhizobium halophilum sp. nov. The type strains are TRM95111T (=CCTCC AB 2021116T =JCM34826T) and TRM950011T (=CCTCC AB 2021095T =JCM34967T), respectively.

Halomonas jincaotanensis sp. nov., isolated from the Pamir Plateau degrading polycyclic aromatic hydrocarbon.

A Gram-strain-negative, rod-shaped, aerobic bacterium, designated strain TRM 85114T, was isolated from the Jincaotan wetland in the Pamir Plateau of China. This strain grew optimally at 30 °C and pH 6.0 in the presence of 3% (w/v) NaCl. Phylogenetic analysis of 16S rRNA gene sequences revealed that strain TRM 85114T was affiliated with the genus Halomonas, and shared high sequence similarity with Halomonas korlensis XK1T (97.3%) and Halomonas tibetensis pyc13T (96.4%). Strain TRM 85114T contained C16:0 and C19:0 cyclo ω8c as primary cellular fatty acids, Q-9 as predominate respiratory quinone, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phospholipids of unknown structure containing glucosamine, unidentified aminophospholipids, unidentified lipids and three unidentified phospholipids as the major polar lipids. The complete genome of TRM 85114T comprised 3,902 putative genes with a total of 4,126,476 bp and a G + C content of 61.6%. The average nucleotide identity and digital DNA-DNA hybridization values between strain TRM 85114T and related type Halomonas strains of H. korlensis XK1T, H. tibetensis pyc13T, Chromohalobacter salexigens DSM 6768T, and Halomonas urumqiensis BZ-SZ-XJ27T were 75.4-88.9% and 22.9-39.2%, respectively. Based on phenotypic, chemotaxonomic, and molecular features, strain TRM 85114T represents a novel species of the genus Halomonas, for which the name is proposed as Halomonas jincaotanensis sp. nov.. The type strain is TRM 85114T (CCTCC AB 2021006T = LMG 32311T). The amount of 1-naphthylamine degradation by strain TRM 85114T reached up to 32.0 mg/L in 14 days.

Streptomyces pimonensis sp. nov., isolated from the Taklimakan desert in Xinjiang, China.

A novel Streptomyces strain, designated TRM 75549T, was isolated from a sample of sand in Pimo reclamation area, Taklimakan desert, Xinjiang, North-West China. Phylogenetic analyses of the 16S rRNA gene sequences placed strain TRM75549T within the genus Streptomyces with the highest similarities to Streptomyces pilosus NBRC 12772T (98.7%). Nonetheless, average nucleotide identity (ANI) value and the digital DNA-DNA hybridization (dDDH) value between strain TRM75549T and S. pilosus NBRC 12772T were, respectively, 88.2% and 44.1%, and well below 95-96% and 70% cutoff point recommended for recognizing genomospecies, respectively. A multi-locus sequence analysis of five house-keeping genes (atpD, gyrB, recA, rpoB and trpB) and phylogenomic analysis also illustrated that strain TRM75549T should also be assigned to the genus Streptomyces. Strain TRM75549T contained MK-9 (H6) and MK-9 (H8) as predominant menaquinones. The diagnostic diamino acid of cell walls were identified as LL-diaminopimelic acid and meso-diaminopimelic. The whole-cell sugar pattern of strain TRM 75549T consisted of mannose and glucose. The major fatty acids (> 5%) were iso-C14:0, iso-C15:0, anteiso-C15:0, iso-C16:1H, iso-C16:0. The polar lipids were diphosphatidylglycerol, lysophosphatidylglycerol, phosphatidylethanolamine, phospholipids, phosphatidylglycerol, phosphatidylinositol, phosphatiylinositol mannosides and unidentified phospholipids. Strain TRM75549T could be differentiated from S. pilosus NBRC 12772T, based on physiological and biochemical characteristics. Thus, strain TRM75549T is representative of a novel species of the genus Streptomyces, for which the name Streptomyces pimonensis sp. nov. is proposed. The type strain is TRM75549T (= CCTCC AA 2020054T = LMG 32221T).

Streptomyces griseicoloratus sp. nov., isolated from soil in cotton fields in Xinjiang, China.

A novel bacterium of the genus Streptomyces, designated TRM S81-3T, was isolated from soil in cotton fields of Xinjiang, China. Comparative 16S rRNA gene sequence analysis indicated that strain TRM S81-3T is most closely related to Streptomyces viridiviolaceus NBRC 13359T (98.9% sequence similarity); however, the average nucleotide identity (ANI) between strains TRM S81-3T and S. viridiviolaceus NBRC 13359T is relatively low (91.6%). Strain TRM S81-3T possesses LL-diaminopimelic acid as the diagnostic cell-wall diamino acid, MK-9(H4), MK-9(H6), and MK-9(H10) as the major menaquinones, and polar lipids including diphosphatidylglycerol (DPG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylmethyl ethanolamine (PME), phosphotidylinositolone (PI), phospholipid of unknown structure containing glucosamine (NPG), and two unidentified phospholipids (PLs).The major fatty acids are iso-C16:0, anteiso-C15:0, anteiso-C17:1 ω9c, anteiso-C17:0, iso-C15:0, and C14:0. The genomic DNA G + C content is 72.1%. Based on the evidence from this polyphasic study, strain TRM S81-3T represents a novel species of Streptomyces, for which the name Streptomyces grisecoloratus is proposed. The type strain is TRM S81-3T (= CCTCC AA 2020002T = LMG 31942T).

Sporosarcina jiandibaonis sp. nov., isolated from saline soil.

A Gram-stain-positive, aerobic, motile, rod-shaped bacterium, designated strain LAM9210T, was isolated from a saline soil sample collected from Lingxian County, Shandong Province, PR China. Analysis of the 16S rRNA gene sequence of the isolate revealed highest sequence similarities to the type strain of Sporosarcina pasteurii NCIMB 8841T (97.6 % sequence similarity). The genomic G+C content was 40.4 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain LAM9210T and the type strain of the most closely related species S. pasteurii NCIMB 8841T were 73.6 and 20.6 %, respectively. Strain LAM9210T was found to grow at 10-40 °C (optimum, 30 °C), at pH 6.0-10.0 (optimum, pH 9.0) and with 0-6 % (w/v) NaCl (optimum, 0.5 %), respectively. The major fatty acids were anteiso-C15 : 0 and iso-C14 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and one unidentified phospholipid. Menaquinone-7 was detected as the predorminant respiratory quinone. Strain LAM9210T contained glycine, lysine, alanine and glutamic acid as the diagnostic amino acids in the cell-wall peptidoglycan. On the basis of phenotypic, phylogenetic and genotypic data, strain LAM9210T is considered to represent a novel species of the genus Sporosarcina, for which the name Sporosarcina jiandibaonis sp. nov. is proposed. The type strain is LAM9210T (=CGMCC 1.18607T=GDMCC 1.2002T=JCM 32514T).

Streptomyces gossypiisoli sp. nov., isolated from cotton soil in Xinjiang, PR China.

A novel actinobacterium, designated TRM 44567T, was isolated from cotton soil in Xinjiang Uygur Autonomous Region, northwest PR China. Growth occurred at 16-45 °C, pH 5.0-9.0, and 0-7 % (w/v) NaCl, with optimum growth at 37 °C, pH 7.0-8.0 and 1 % (w/v) NaCl, respectively. Comparative 16S rRNA gene sequence analysis indicated that strain TRM 44567T was phylogenetically most closely related to Streptomyces chromofuscus NBRC 12851T (98.48 % sequence similarity); however, the average nucleotide identity between strain TRM 44567T and S. chromofuscus NBRC 12851T was only 83.77 %. Strain TRM 44567T possessed ll-diaminopimelic acid as the diagnostic cell-wall diamino acid. The predominant menaquinones were MK-9(H10), MK-9(H6) and MK-9(H4). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol and phosphatidylinositol mannoside. The major fatty acids were iso-C16 : 0, C16 : 0, anteiso-C15 : 0, anteiso-C17 : 0, iso-C14 : 0 and iso-C15 : 0. The genomic DNA G+C content was 70.8 mol%. Strain TRM 44567T represents a novel species of the genus Streptomyces, for which the name Streptomyces gossypiisoli sp. nov. is proposed. The type strain is TRM 44567T (=KCTC 39957 T=CCTCC AA 2017011T).

Microbacterium karelineae sp. nov. isolated from a halophyte plant in the Taklamakan desert.

A bacterial strain, designated TRM 80801T, was isolated from the Karelinea in Taklamakan desert, Xinjiang Uygur Autonomous Region, north-west China. Cells were Gram-stain-positive, aerobic, non-motile, short rods. Strain TRM 80801T grew at 4-50 °C, with optimum growth at 28 °C, and grew at pH 6.0-11.0 and 1-15 % (w/v) NaCl. Phylogenetic analyses of the 16S rRNA gene sequences placed strain TRM 80801T within the genus Microbacterium with the highest similarities to Microbacterium suaedae YZYP 306T (98.97 %) and Microbacterium indicum BBH6T (98.17 %), respectively. The DNA G+C content of TRM 80801T is 69.38 mol%. The cell-wall peptidoglycan contained the amino acids ornithine, glutamic acid, glycine and alanine, the diagnostic diamino acid was ornithine. The acyl type of the peptidoglycan was glycolyl. Whole-cell sugars were ribose, mannose, glucose, rhamnose and galactose. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The predominant menaquinones were MK-10, MK-11 and MK-12. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol. The whole-genome average nucleotide identity (ANI) value between strain TRM 80801T and Microbacterium suaedae YZYP 306T is 70.2 %. On the basis of the evidence presented in this study, strain TRM 80801T is representative of a novel species in the genus Microbacterium, for which the name Microbacterium karelineae sp. nov. is proposed. The type strain is TRM 80801T (=CCTCC AB 2019248T=KCTC 49357T).

Streptomyces polyasparticus sp. nov. isolated from cotton field soil by a medium applied with polyaspartic acid.

A novel Streptomyces strain (TRM66268-LWLT) was isolated from cotton field soil by a medium supplied with polyaspartic acid (PASP) at Alar, Xinjiang, Northwest PR China, and characterized using a polyphasic taxonomic approach. The strain was found to degrade PASP, and grow well on the medium to take PASP as the sole carbon source. The TRM66268-LWLT fermentation broth was applied to the surface of PASP, and there were pores on the surface of PASP after a period of time. The strain was observed to be Gram-stain-positive and to form greyish-white aerial mycelia that differentiated into straight spore chains with round spores. The whole-cell sugar pattern of TRM 66268-LWLT consisted of ribose, mannose and arabinose, and the principal phospholipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside, phosphatidylinositol and two undetermined polar lipids. The predominant menaquinones were MK-7, MK-7(H4), MK-9(H8), MK-10(H6). The diagnostic cell wall amino acid was identified as LL-diaminopimelic acid. The G+C content of strain TRM66268-LWLT was 70.11 mol%. The average nucleotide identity value between strain TRM66268-LWLT and the phylogenetically related strain Streptomyces indicus IH32-1T was calculated to be 85.49%. The digital DNA-DNA hybridization value between them was 30.40%. A multilocus sequence analysis of five house-keeping genes (atpD, gyrB, rpoB, recA and trpB) also illustrated that strain TRM66268-LWLT should be assigned to the genus Streptomyces. On the basis of evidence from polyphasic study, strain TRM66268-LWLT is designated as representing a novel species of the genus Streptomyces, for which the name Streptomyces polyasparticus sp. nov. is proposed. The type strain is TRM66268-LWLT (CCTCC AA 2020003T = LMG32106T).

Streptomyces albicerus sp. nov., a novel actinomycete isolated from the sediments of the Tailan River in Xinjiang, China.

A novel actinomycete, designated TRM68295T, was isolated from the sediments of the Tailan River, Xinjiang, northwest China. The study of the polyphasic approach showed that the characteristics of the strain were consistent with the genus Streptomyces. Phylogenetic analysis indicated that the strain had a high sequence similarity with Streptomyces phaeochromogenes ATCC 3338T (97.9%). The diagnostic diamino acid of cell walls was identified as LL-diaminopimelic acid. The whole cell sugars were identified as ribose, xylose, glucose and galactose. The major fatty acids were iso-C14:0, iso-C15:0, anteiso-C15:0, iso-C16:0, C16:1ω9c, C16:0 and anteiso-C17:0. The major menaquinones were MK-9 (H10), MK-9 (H6) and MK-9 (H2). The polar lipids were composed of diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI) and phosphatidylinositol mannoside (PIM). The G+C content in the draft genome sequence of the strain was identified as 70.0 mol%. The average nucleotide identity (ANI) between strains TRM68295T and S. phaeochromogenes ATCC 3338T was 88.1%. Digital DNA-DNA hybridization (dDDH) value between strain TRM68295T and S. phaeochromogenes ATCC 3338T was 40.7%. The multilocus sequence analysis of five house-keeping genes (atpD, gyrB, recA, rpoB, and trpB) indicated that the MLSA distances between the strain and similar species were greater than the threshold of 0.007. Based on the above studies, strain TRM68295T is considered as a novel species of the genus Streptomyces, for which the name Streptomyces albicerus sp. nov. is proposed. The type strain is TRM68295T (= CCTCC AA 2018085T = KCTC 49272T).

Streptomyces arboris sp. nov., isolated from Populus euphratica wetland soil.

A novel actinobacterial strain (TRM 68085T) was isolated from soil of Populus euphratica wetland. A polyphasic approach was used to study the taxonomy of TRM 68085T and the results showed a range of phylogenetic and chemotaxonomic properties consistent with those of the genus Streptomyces. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain TRM 68085T showed the highest similarity value to Streptomyces capitiformicae 1H-SSA4T (98.6 %), and phylogenetically clustered with Streptomyces kanasensis ZX01T(97.5 %) and Streptomyces ipomoeae NBRC 13050T (97.4 %). The genomic DNA G+C content of strain TRM 68085T based on the genome sequence was 71.4 mol%. The levels of DNA-DNA relatedness between the genome of the isolate and its nearest phylogenetic neighbours, S. capitiformicae 1H-SSA4T, S. kanasensis ZX01T and S. ipomoeae NBRC 13050T, were 19.2±0.4, 21.8±0.5 and 19.3±0.6 %, respectively. Chemotaxonomic data revealed that strain TRM 68085T possessed MK-9(H6) and MK-9(H8) as the predominant menaquinones. ll-Diaminopimelic acid and a small amount of meso-diaminopimelic acid were the diagnostic diamino acids. Ribose, xylose, glucose and galactose were the whole-cell sugars. The major cellular fatty acids were C16 : 0 (25.4 %) and iso-C16 : 0 (18.3 %). On the basis of these genotypic and phenotypic data, it is concluded that strain TRM 68085T represents a novel species of the genus Streptomyces, for which the name Streptomyces arboris sp. nov. is proposed. The type strain is TRM 68085T (=CCTCC AA2019031T=LMG 31492T).

Streptomyces lycii sp. nov., an endogenous actinomycete isolated from Lycium ruthenicum.

A novel endogenous actinobacteria strain, designated TRM 66187T, was isolated from Lycium ruthenicum sampled at Alar, Xinjiang, Northwest PR China, and characterized using a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences affiliated strain TRM 66187T with the genus Streptomyces. The whole-cell sugar pattern of TRM 66187T consisted of galactose, glucose and ribose. The predominant menaquinones were MK-9(H4) and MK-9(H6). Major cellular fatty acids were iso-C14:0, iso-C15:0, anteiso-C15:0 and anteiso-C16:0. The detected polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and two unidentified polar lipids. The G+C content of strain TRM 66187T was 71.8 mol%. Results of phylogenetic analysis showed that strain TRM 66187T had 98.48% 16S rRNA gene sequence similarity to the closest described species Streptomyces qinglanensis DSM 42035T. The average nucleotide identity value between strain TRM 66187T and the closest related strain Streptomyces qinglanensis DSM 42035T was calculated to be 77.2%. The digital DNA-DNA hybridization value between them was 22.4%. Multilocus sequence analyses based on five housekeeping genes (atpD, gyrB, recA, rpoB and trpB) also indicated that strain TRM 66187T should be assigned to the genus Streptomyces. On the basis of evidence from this polyphasic study, strain TRM 66187T should be designated as representing a novel species of the genus Streptomyces, for which the name Streptomyces lycii sp. nov. is proposed. The type strain is TRM 66187T (=LMG 31493T=CCTCC AA 2018094T).

Streptomyces tailanensis sp. nov., an actinomycete isolated from riverside silt.

A novel actinobacterium, designated TRM68348T, was isolated from the silt collected from the Tailan River in Xinjiang Province, north-west China. The strain was aerobic and Gram-stain-positive. The aerial mycelium was densely straight or tortuous, with a few branches of hyphae and no spores. The whole-cell sugar pattern of strain TRM68348T consisted of ribose and glucose. The diagnostic diamino was ll-diaminopimelic acid. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannose and an unidentified phospholipid. The predominant menaquinones were MK-9 (H10), MK-9 (H6) and MK-9 (H2). The major fatty acids (>5 %) were iso-C14 : 0, iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, C16 : 0 and summed feature 6. The G+C content of the genomic DNA was 69.93 mol%. Phylogenetic analysis showed that strain TRM68348T shared 16S rRNA gene sequence similarity of 98.14 % to the closest described species Streptomyces capitiformicae 1H-SSA4T. Strain TRM68348T had a relatively low DNA-DNA relatedness value with S. capitiformicae 1H-SSA4T as determined by calculating the average nucleotide identity value (92.78 %). Strain TRM68348T could also be differentiated from S. capitiformicae 1H-SSA4T based on morphological and physiological characteristics. On the basis of the evidence from this polyphasic study, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces tailanensis sp. nov. is proposed. The type strain is TRM68348T (=CCTCC AA 2018086T=KCTC 49274T).

Actinokineospora pegani sp. nov., an endophytic actinomycete isolated from the surface-sterilized root of Peganum harmala L.

A novel Gram-positive, aerobic and motile endophytic actinomycete, designated TRM 65233T, was isolated from the root of Peganum harmala L. collected from Xinjiang Uygur Autonomous Region of China. The isolate had white aerial mycelium and brown substrate mycelium on Gause's synthetic agar. Growth occurred at 10-40 °C, pH 6-9 with NaCl concentration of 0-6 % (w/v). Strain TRM 65233T contained meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The whole-cell hydrolysates included glucose and galactose as the major whole-cell sugars. The menaquinones were MK-9 (H4) and MK-7. The major cellular fatty acids were iso-C16 : 0, iso-C15 : 0 and anteiso-C17 : 0. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phospholipids, phosphatidylinositol and one unidentified lipid. Strain TRM 65233T showed the highest 16S rRNA gene sequence similarity to Actinokineospora cianjurensis BTCC B-558T (98.13 %), Actinokineospora auranticolor IFO 16518T (98.06 %), Actinokineospora spheciospongiae EG49T (97.99 %), Actinokineospora baliensis ID03-0561T (97.97 %), Actinokineospora mzabensis PAL84T (97.95 %) and Actinokineospora bangkokensis 44EHWT (97.06 %). The isolate was distinguished from these phylogenetically related strains by digital DNA-DNA hybridization and average nucleotide identity analyses and by a range of physiological and biochemical characteristics. The G+C content of the genomic DNA was 72.6 mol%. On the basis of polyphasic taxonomic data, strain TRM 65233T represents a novel species of the genus Actinokineospora, for which the name Actinokineospora pegani sp. nov. is proposed. The type strain is TRM 65233T (KCTC 49342=CCTCC AA 2019050).

Streptomyces apocyni sp. nov., an endogenous actinomycete isolated from Apocynum venetum.

A novel actinomycete, designated strain TRM 66233T, was isolated from Apocynum venetum L. collected from the Xinjiang Uygur Autonomous Region of China and characterized using a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences affiliated strain TRM 66233T with the genus Streptomyces. Strain TRM 66233T showed a high similarity value to Streptomyces bikiniensis NRRL B-1049T (98.07 %) based on the 16S rRNA gene phylogenetic tree. The whole-cell sugar pattern of TRM 66233T consisted of glucose, galactose, mannose and ribose. The predominant menaquinones were MK-9(H2), MK-9(H6), MK-9(H8) and MK-9(H10). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and four unidentified lipids. The major fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, C16 : 0 and iso-C17 : 0. The G+C content of the DNA was 70.35 mol%. The DNA-DNA relatedness and average nucleotide identity values as well as evolutionary distances based on multilocus (atpD, gyrB, recA, rpoB and trpB) sequences between strain TRM 66233T and closely related type strains were significantly lower than the recommended threshold values. The whole-genome average nucleotide identity and digital DNA-DNA hybridization values between strain TRM 66233T and S. bikiniensis NRRL B-1049T were 78.86 and 23.2 %, respectively. On the basis of evidence from this polyphasic study, strain TRM 66233T should represent a novel species of the genus Streptomyces, for which the name Streptomyces apocyni sp. nov. is proposed. The type strain is TRM 66233T (=CCTCC AA 2019056T=LMG 31559T).

Streptomyces roseicoloratus sp. nov., isolated from cotton soil.

A novel bacterium, designated TRM 44457T, belonging to the genus Streptomyces, was isolated from soil sampled in cotton fields in Xinjiang, PR China. Comparative 16S rRNA gene sequence analysis indicated that strain TRM 44457T was phylogenetically most closely related to Streptomyces laurentii LMG 19959T (99.38 % sequence similarity); however, strain TRM 44457T had a relatively low DNA-DNA relatedness value with S. laurentii LMG 19959T as determined by calculating the average nucleotide identity value (84.42 %). Strain TRM 44457T possessed ll-diaminopimelic acid as the diagnostic cell-wall diamino acid, MK-9 (H6) and MK-9 (H10) as the major menaquinone. The polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphotidylinositol, phosphatidylinositol mannosides and an unidentified phospholipid. The major fatty acids were anteiso-C15:0, iso-C16:0, anteiso-C17:0, iso-C15:0, C16:0, iso-C17:0, cyclo-C17:0 and anteiso-C17:1ω9c. The genomic DNA G+C content was 72.6 mol%. Based on the evidence from this polyphasic study, strain TRM 44457T represents a novel species of the Streptomyces, for which the name Streptomyces roseicoloratus is proposed. The type strain is TRM 44457T (=KCTC 39904T=CCTCC AA 2016040T).

Streptomyces taklimakanensis sp. nov., an actinomycete isolated from the Taklimakan desert.

A novel Streptomyces strain, designated TRM43335T, was isolated from the Taklimakan desert in Alar City, Xinjiang, north-west China. The strain was found to exhibit an inhibitory effect on biofilm formation by Candida albicans and Staphylococcus epidermidis. A polyphasic approach was used to determine its taxonomic status. The strain was observed to form abundant aerial mycelium, occasionally twisted and which differentiated into spiral spore chains. Spores of TRM43335T were observed to be oval-shaped, with a smooth surface. Strain TRM43335T was found to grow optimally at 37 °C, pH 8 and in the presence of 1% (w/v) NaCl. The major sugars were identified as ribose, xylose, glucose, mannose and galactose, and the principal phospholipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannoside and phosphatidylinositol. The diagnostic cell wall amino acid was identified as LL-diaminopimelic acid. The predominant menaquinone was found to be MK-9(H6). The major cellular fatty acids were identified as iso-C16:1 H, anteiso-C15:0, iso-C16:0, anteiso-C17:0, anteiso-C17:1 w9c and iso-C15:0. Analysis of the 16S rRNA sequence showed that strain TRM43335T exhibits high sequence similarity to Streptomyces desertarenae SYSU D8023T 98.69%. A multilocus sequence analysis of five house-keeping genes (atpD, gyrB, rpoB, recA and trpB) also illustrated that strain TRM43335T should be assigned to the genus Streptomyces. The DNA G + C content of the strain was determined to be 72.8 mol%. The average nucleotide identity relatedness between strain TRM43335T and the phylogenetically related strain S. desertarenae SYSU D8023T was found to be 89.23%, and the in silico DNA-DNA hybridization value to be 36.70%. Therefore, it is concluded that strain TRM43335T represents a novel species of the genus Streptomyces, for which the name Streptomyces taklimakanensis sp. nov is proposed. The type strain is TRM43335T (CCTCC AA 2018052 T = KCTC 49254 T).