Bacillus licheniformis Jrh14-10 enhances alkaline tolerance in Arabidopsis thaliana by regulating crosstalk between ethylene and polyamine pathways.

Plant growth-promoting rhizobacteria (PGPR) are known for their role in ameliorating plant stress, including alkaline stress, yet the mechanisms involved are not fully understood. This study investigates the impact of various inoculum doses of Bacillus licheniformis Jrh14-10 on Arabidopsis growth under alkaline stress and explores the underlying mechanisms of tolerance enhancement. We found that all tested doses improved the growth of NaHCO3-treated seedlings, with 109 cfu/mL being the most effective. Transcriptome analysis indicated downregulation of ethylene-related genes and an upregulation of polyamine biosynthesis genes following Jrh14-10 treatment under alkaline conditions. Further qRT-PCR analysis confirmed the suppression of ethylene biosynthesis and signaling genes, alongside the activation of polyamine biosynthesis genes in NaHCO3-stressed seedlings treated with Jrh14-10. Genetic analysis showed that ethylene signaling-deficient mutants (etr1-3 and ein3-1) exhibited greater tolerance to NaHCO3 than the wild type, and the growth-promoting effect of Jrh14-10 was significantly diminished in these mutants. Additionally, Jrh14-10 was found unable to produce 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, indicating it does not reduce the ethylene precursor ACC in Arabidopsis. However, Jrh14-10 treatment increased the levels of polyamines (putrescine, spermidine, and spermine) in stressed seedlings, with spermidine particularly effective in reducing H2O2 levels and enhancing Fv/Fm under NaHCO3 stress. These findings reveal a novel mechanism of PGPR-induced alkaline tolerance, highlighting the crosstalk between ethylene and polyamine pathways, and suggest a strategic redirection of S-adenosylmethionine towards polyamine biosynthesis to combat alkaline stress.

Unravelling Species Diversity and Pathogenicity of Fusarium spp. Associated with Soybean Leaf and Root in Heilongjiang Province, China.

Soybean (Glycine max L.) holds significant global importance and is extensively cultivated in Heilongjiang Province, China. Soybean can be infected by Fusarium species, causing root rot, seed decay, stem rot, and leaf blight. In 2021 to 2022, a field survey of soybean diseases was carried out in 11 regions of Heilongjiang Province, and 186 soybean leaves with leaf blight symptoms and 123 soybean roots with root rot symptoms were collected. Unexpectedly, a considerable number of Fusarium isolates were obtained not only from root samples but also from leaf samples. A total of 584 Fusarium isolates (416 from leaves and 168 from roots) were obtained and identified as 18 Fusarium species based on morphological features and multilocus phylogenetic analyses with tef1 and rpb2 sequences. Fusarium graminearum and Fusarium sp. 1 in FOSC were the dominant species within soybean leaf and root samples, respectively. Pathogenicity tests were conducted for all Fusarium isolates on both soybean leaves and roots. Results showed that F. graminearum, F. ipomoeae, F. citri, F. compactum, F. flagelliforme, F. acuminatum, and F. sporotrichioides were pathogenic to both soybean leaves and roots. F. solani, F. avenaceum, F. pentaseptatum, F. serpentinum, F. annulatum, and Fusarium sp. 1 in FOSC were pathogenic to soybean roots, not to leaves. To our knowledge, this is the first study to thoroughly investigate soybean-associated Fusarium populations in leaves and roots in Heilongjiang Province.

Description of Jidongwangia harbinensis gen. nov. sp. nov.

During our previous study, strain NEAU-J3T was classified as representing a novel genus 'Wangella' within the family Micromonosporaceae. Nevertheless, it is a great pity the name cannot be validated as the proposed genus name is illegitimate (Principle 2 of the ICNP). In this study, we describe Jidongwangia as a novel genus within the family Micromonosporaceae and a polyphasic approach was used to provide evidence to support the classification. The G+C content of the genomic DNA of the type strain is 71.6 %. Digital DNA-DNA hybridization and average nucleotide identity (ANI) values could be used to differentiate NEAU-J3T from its related type strains. The phenotypic, genetic and chemotaxonomic data also indicated that NEAU-J3T occupies a branch separated from those of known genera in the family Micromonosporaceae. Therefore, NEAU-J3T represents a novel species of a novel genus in the family Micromonosporaceae, for which the name Jidongwangia harbinensis gen. nov., sp. nov. is proposed. The type strain of Jidongwangia harbinensis is NEAU-J3T (= CGMCC 4.7039T = DSM 45747T).

Identification, Characterization, and Pathogenicity of Fungi Associated with Strawberry Fruit Rot in Shandong Province, China.

China is the largest strawberry producer and exporter worldwide and has been constantly challenged by fruit rot diseases in recent years. Symptoms of various diseases on strawberry fruits were observed in Huangqiyuan Base, an important strawberry-producing region in Shandong Province, and symptomatic samples were collected from January to April 2021 for follow-up studies. In the present study, 137 isolates were obtained and classified into nine species based on morphological characteristics and multilocus phylogenetic analysis (ITS, GAPDH, HIS3, RPB2, EF-1α, HSP60, G3PDH, and/or TUB2), namely, Botrytis cinerea, B. fabiopsis, Alternaria alternata, A. tenuissima, Fusarium proliferatum, F. graminearum, F. ipomoeae, F. incarnatum, and Colletotrichum siamense. Pathogenicity results suggested that all nine pathogenic species could induce fruits to exhibit symptoms similar to those naturally infected in fields. The symptoms around the inoculation points varied, including dense white mycelia caused by Botrytis spp., fading and depression caused by Fusarium spp., black-brown rot caused by Alternaria spp., and shrinkage and dehydration caused by Colletotrichum spp. Overall, B. cinerea was the dominant pathogen, accounting for 61.3% of the total isolates, and showed significantly higher virulence against strawberry fruits than other species. In addition, this is the first report to identify B. fabiopsis, A. alternata, A. tenuissima, F. proliferatum, F. graminearum, F. ipomoeae, and F. incarnatum as causal agents of strawberry fruit rot in Shandong Province, China.

Diversity and Pathogenicity of Fungi Associated with Fruit Rot of Winter Jujube in Shandong Province, China.

Winter jujube originated from China and had an extremely high nutritional value. In 2021, symptomatic winter jujube fruits were collected from eight locations in Zhanhua District of Binzhou City, Shandong Province. In total, 108 fungal isolates were obtained and grouped into 11 species based on morphological characteristics and multilocus phylogenetic analysis, including Nothophoma quercina (43.52%), Fusarium lateritium (20.37%), Alternaria alternata (12.03%), F. proliferatum (7.41%), F. graminearum (4.63%), Botryosphaeria dothidea (3.70%), Fusarium sp. (2.78%), A. tenuissima (2.78%), Diaporthe eres (1.85%), Nigrospora oryzae (0.93%), and Cercospora nicotianae (0.93%). All fungal isolates obtained in this study showed aggressiveness on detached winter jujube fruits except N. oryzae and C. nicotianae isolates, of which F. proliferatum was the most virulent, while A. alternata isolates, which have been considered the major pathogen of winter jujube fruit rot, showed a relatively low-level virulence in this study. Furthermore, D. eres, F. graminearum, F. lateritium, and an unclassified Fusarium species were first reported as causal agents of winter jujube fruit rot. The typical symptoms of winter jujube fruit rot observed in this study could be distinguished into two types. N. quercina, A. alternata, A. tenuissima, Fusarium sp., D. nobilis, and F. lateritium isolates caused reddish brown to dark gray lesions on the peel, while B. dothidea, F. graminearum, and F. proliferatum isolates caused peel and pulp decay, resulting in red to reddish brown and water-soaked lesions. In addition, haplotype analysis of N. quercina isolates obtained in this study and validly published articles showed that there were 11 haplotypes worldwide; the isolates obtained in the current study were grouped into three haplotypes (Hap 1, Hap 2, and Hap 11), and two of them (Hap 2 and Hap 11) were confirmed as new haplotypes.

Function of Transcription Factors PoMYB12, PoMYB15, and PoMYB20 in Heat Stress and Growth of Pleurotus ostreatus.

MYB transcription factors (TFs) have been extensively studied in plant abiotic stress responses and growth and development. However, the role of MYB TFs in the heat stress response and growth and development of Pleurotus ostreatus remains unclear. To investigate the function of PoMYB12, PoMYB15, and PoMYB20 TFs in P. ostreatus, mutant strains of PoMYB12, PoMYB15, and PoMYB20 were generated using RNA interference (RNAi) and overexpression (OE) techniques. The results indicated that the mycelia of OE-PoMYB12, OE-PoMYB20, and RNAi-PoMYB15 mutant strains exhibited positive effects under heat stress at 32 °C, 36 °C, and 40 °C. Compared to wild-type strains, the OE-PoMYB12, OE-PoMYB20, and RNAi-PoMYB15 mutant strains promoted the growth and development of P. ostreatus. These mutant strains also facilitated the recovery of growth and development of P. ostreatus after 24 h of 36 °C heat stress. In conclusion, the expression of PoMYB12 and PoMYB20 supports the mycelium's response to heat stress and enhances the growth and development of P. ostreatus, whereas PoMYB15 produces the opposite effect.

Nucisporomicrobium flavum gen. nov., sp. nov., a new member of the family Micromonosporaceae isolated from saline-alkali soil.

A Gram-stain-positive, aerobic actinobacterium, designated strain NEAU-24T, was isolated from saline-alkali soil collected from Daqing City, Heilongjiang Province, PR China. Strain NEAU-24T was found to produce abundant substrate mycelia but no aerial hyphae. The substrate mycelia formed irregular pseudosporangia consisting of nuciform spores, and the surface of the spores was smooth. 16S rRNA gene sequence analysis showed that strain NEAU-24T clustered with Pseudosporangium ferrugineum 3-44-a(19)T, Couchioplanes caeruleus subsp. azureus DSM 44103T and C. caeruleus subsp. caeruleus DSM 43634T within the family Micromonosporaceae and was most closely related to P. ferrugineum 3-44-a(19)T (99.17 %). The strain contained meso-diaminopimelic acid as the cell-wall diamino acid and MK-9(H6) as the menaquinone. The whole cell sugar profile consisted of glucose, galactose, xylose and arabinose. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, phosphatidylinositol and an unidentified lipid. The major fatty acids were summarized as C16 : 0, C15 : 0, C17 : 0, iso-C16 : 0 and iso-C17 : 0. The low digital DNA-DNA hybridization and average nucleotide identity values could differentiate strain NEAU-24T from its related type strains. The phenotypic, genetic and chemotaxonomic data also indicated that strain NEAU-24T occupied a branch separated from those of known genera in the family Micromonosporaceae. In addition, genomic analysis confirmed that strain NEAU-24T had the potential to produce chitinase. Therefore, strain NEAU-24T represents a novel species of a new genus and species in the family Micromonosporaceae, for which the name Nucisporomicrobium flavum gen. nov., sp. nov. is proposed. The type strain of Nucisporomicrobium flavum is NEAU-24T (=CCTCC AA 2020016T=JCM 33973T).

First Report of Alternaria tenuissima Causing Leaf spot on Luffa cylindrica in China.

In August 2020-2021, symptoms of leaf spot were observed in luffa (Luffa cylindrical) fields in Qingdao city, Shandong Province. In all the 10 fields investigated, leaf spot occurred. The incidence (% luffa plants with symptoms from a defined number of plants assessed) was 35 to 60%. Early symptoms of infected leaves were small and irregular chlorotic lesions which later became irregular brown spots. As the disease progressed, the lesions gradually spread from the edge to the center of leaves to the middle, and became dark brown. The enlarged spots coalesced and eventually led to the withering and death of the leaves. In order to isolate the pathogen, 30 symptomatic leaves were collected from different planting fields. Small pieces of leaf tissues (5×5 mm) were cut from the junction of healthy and diseased tissues, sanitized with 2% NaClO for 1 min, rinsed three times with sterile distilled water. The tissue samples were then placed on potato dextrose agar (PDA) amended with 50 mg/L streptomycin sulfate, and incubated at 28℃ for 5 days in the dark. Ten purified fungal isolates were obtained by single spore isolation method. Colonies of these fungal isolates on the PDA medium were initially grayish-white, and then turned olive green with abundant cotton-like aerial hyphae. On potato carrot agar (PCA) medium, these fungi produced light brown and solitary conidiophore with septum. Conidia were obclavate or ellipsoid, brown, with 1-5 transverse septa and 0-3 longitudinal septa, and measured 13.2 to 49.5 × 9.5 to 21.6 µm (n=50). The morphological characteristics of these isolates were consistent with that of Alternaria spp. (Simmons 2007). The representative isolate NEAU-SG-1 was selected for molecular identification. The internal transcribed spacer (ITS) region of ribosomal DNA, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1-α gene (TEF), histone 3 (HIS3), and RNA polymerase II second largest subunit (RPB2) were amplified using primer pairs ITS1/ITS4 (White et al. 1990), gpd1/gpd2 (Berbee et al. 1999), EF1-728F/EF1-986R (Carbone and Kohn 1999), H3-1a/H3-1b (Glass and Donaldson 1995), and RPB2-5F2/fRPB2-7cR (Sung et al. 2007), respectively. Sequences of these genes of isolate NEAU-SG-1 were deposited into GenBank database with the accession numbers of OL307719, OL415166, OL415169, OL415167, and OL415168. BLAST analysis of these sequences showed 99-100% homology with sequence homology with Alternaria tenuissima strains (ITS, MH824269; GAPDH, MK683783; TEF, MN056178; HIS3, MH824371; RPB2, LC621694). To fulfill Koch's postulates, ten surface disinfected 30-day-old luffa seedlings were inoculated by spraying conidia suspension (106 conidia/ml) of isolate NEAU-SG-1. The other ten surface disinfected seedlings inoculated with sterile distilled water served as the control group. After inoculation, each plant was covered with plastic bags for three days and cultured in greenhouse at 25℃. One week later, leaves inoculated with conidia suspension were observed with the same symptoms as described above, while the leaves of the control group were asymptomatic. Pathogenicity test was repeated twice. The Alternaria isolates were successfully re-isolated from those infected leaves and identified using the morphological and molecular methods described above. A. tenuissima has a wide host range in the world, and is the pathogen of leaf spot of many crops (Ma et al. 2021). To our knowledge, this is the first report of A. tenuissima causing leaf spot on luffa in China. This report will provide basic information for the diagnosis and prevention and control strategies of luffa leaf spot.

Alternaria spp. Associated with Leaf Blight of Maize in Heilongjiang Province, China.

Maize (Zea mays L.) is a major economic crop worldwide. Maize can be infected by Alternaria species causing leaf blight that can result in significant economic losses. In this study, 168 Alternaria isolates recovered from symptomatic maize leaves were identified based on morphological characteristics, pathogenicity, and multilocus sequence analyses of the genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the internal transcribed spacer of ribosomal DNA (rDNA ITS), the RNA polymerase II second largest subunit (RPB2), and histone3 (HIS3). Maize isolates grouped to four Alternaria species including Alternaria tenuissima, A. alternata, A. burnsii, and Alternaria sp. Notably, A. tenuissima (71.4%) was the most prevalent of the four isolated species, followed by A. alternata (21.5%), Alternaria sp. (4.1%), and A. burnsii (3.0%). Pathogenicity tests showed that all four Alternaria species could produce elliptic to nearly round, or strip, lesions on leaves of maize, gray-white to dry white in the lesion centers and reddish-brown at the edges. The average disease incidence (58.47%) and average disease index (63.55) of maize leaves inoculated with A. alternata were significantly higher than levels resulting from A. tenuissima (55.28% and 58.49), Alternaria sp. (55.34% and 58.75), and A. burnsii (56% and 55). Haplotype analyses indicated that there were 14 haplotypes of A. tenuissima and five haplotypes of A. alternata in Heilongjiang Province and suggested the occurrence of a population expansion. Results of the study showed that Alternaria species associated with maize leaf blight in Heilongjiang Province are more diverse than those that have been previously reported. This is the first report globally of A. tenuissima, A. burnsii, and an unclassified Alternaria species as causal agents of leaf blight on maize.

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-LD23T 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-LD23T (=CCTCC AA 2019029T=DSM 109824T). In addition, strain NEAU-LD23T 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-LD23T significantly inhibited mycelial growth of B. cinerea. To preliminarily explore the antifungal mechanisms, the genome of strain NEAU-LD23T 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.

Microbacterium stercoris sp. nov., an indole acetic acid-producing actinobacterium isolated from cow dung.

A novel growth-promoting and indole acetic acid-producing strain, designated NEAU-LLBT, was isolated from cow dung collected from Shangzhi, Heilongjiang Province, PR China. Cells of strain NEAU-LLBT were Gram-stain-positive, non-motile, aerobic and non-spore-forming. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain NEAU-LLBT belonged to the genus Microbacterium. Strain NEAU-LLBT had high 16S rRNA sequence similarities of 98.81 and 98.41 % to Microbacterium paludicola DSM 16915T and Microbacterium marinilacus DSM 18904T, and less than 98 % to other members of the genus Microbacterium. Chemotaxonomic characteristics showed that MK-11 and MK-12 were detected as the predominant menaquinones. The peptidoglycan contained glutamic acid, aspartic acid, glycine, ornithine and a small amount of alanine, with ornithine as the diagnostic diamino acid. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The major fatty acids were identified as anteiso-C15 : 0, iso-C16 : 0 and iso-C17 : 0. The genomic DNA G+C content of strain NEAU-LLBT was 70.2 mol%. In addition, the average nucleotide identity values between strain NEAU-LLBT and its reference strains, M. paludicola DSM 16915T, M. marinilacus DSM 18904T and M. album SYSU D8007T, were found to be 81.1, 79.4 and 78.7 %, respectively, and the level of digital DNA-DNA hybridization between them were 23.8, 22.6 and 21.8 %, respectively. Based on the phenotypic, phylogenetic and genotypic data, strain NEAU-LLBT is considered to represent a novel species of the genus Microbacterium, for which the name Microbacterium stercoris sp. nov is proposed, with NEAU-LLBT (=CCTCC AA 2018028T=JCM 32660T) as the type strain.

Microbispora sitophila sp. nov., a novel actinobacterium isolated from rhizosphere soil of wheat (Triticum aestivum L.).

A novel actinobacterium, designated strain NEAU-D428T, was isolated from rhizosphere soil of wheat and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the strain coincided with members of the genus Microbispora. The 16S rRNA gene sequence analysis showed that the isolate was most closely related to Microbispora bryophytorum NEAU-TX2-2T (99.2 %). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the strain clustered with Microbispora clausenae CLES2T (99.1 %), but formed a separate subclade in the phylogenomic tree within the genus Microbispora. The menaquinones were identified as MK-9(H4), MK-9(H2) and MK-9(H0). The phospholipid profile was found to consist of diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, ninhydrin-positive glycophospholipid, phosphatidylinositol and phosphatidylinositol mannoside. The major fatty acids were identified as iso-C16 : 0, C16 : 0, 10-methyl C17 : 0 and C18 : 0. Digital DNA-DNA hybridization and average nucleotide identity values between strain NEAU-D428T and M. bryophytorum NEAU-TX2-2T, Microbispora camponoti 2C-HV3T, M. clausenae CLES2T, 'Microbispora cellulosiformans' Gxj-6T and Microbispora fusca NEAU-HEGS1-5T were 47.6 and 92.2 %, 47.5 and 92.2 %, 55.9 and 94.0 %, 33.1 and 86.8 %, and 33.6 and 87.1 %, respectively. These results and some physiological and biochemical properties demonstrated that the strain could be distinguished from its closest relatives. Therefore, it is proposed that strain NEAU-D428T should be classified as representative of a novel species of the genus Microbispora, for which the name Microbispora sitophila sp. nov. is proposed. The type strain is NEAU-D428T (=CGMCC 4.7523T=DSM 109822T).

Streptosporangium jiaoheense sp. nov. and Streptosporangium taraxaci sp. nov., actinobacteria isolated from soil and dandelion root (Taraxacum mongolicum Hand.-Mazz.).

Two novel actinobacteria, designated strains NEAU-Jh1-4T and NEAU-Wp2-0T, were isolated from muddy soil collected from a riverbank in Jiaohe and a dandelion root collected from Harbin, respectively. A polyphasic study was carried out to establish the taxonomic positions of these two strains. The phylogenetic analysis based on the 16S rRNA gene sequences of strains NEAU-Jh1-4T and NEAU-Wp2-0T indicated that strain NEAU-Jh1-4T clustered with Streptosporangium nanhuense NEAU-NH11T (99.32 % 16S rRNA gene sequence similarity), Streptosporangium purpuratum CY-15110T (98.30 %) and Streptosporangium yunnanense CY-11007T (97.95 %) and strain NEAU-Wp2-0T clustered with 'Streptosporangium sonchi ' NEAU-QS7 (99.39 %), 'Streptosporangium kronopolitis' NEAU-ML10 (99.26 %), 'Streptosporangium shengliense' NEAU-GH7 (98.85 %) and Streptosporangium longisporum DSM 43180T (98.69 %). Moreover, morphological and chemotaxonomic properties of the two isolates also confirmed their affiliation to the genus Streptosporangium. However, the low level of DNA-DNA hybridization and some phenotypic characteristics allowed the isolates to be differentiated from the most closely related species. Therefore, it is proposed that strains NEAU-Jh1-4T and NEAU-Wp2-0T represent two novel species of the genus Streptosporangium, for which the name Streptosporangium jiaoheense sp. nov. and Streptosporangium taraxaci sp. nov. are proposed. The type strains are NEAU-Jh1-4T (=CGMCC 4.7213T=JCM 30348T) and NEAU-Wp2-0T (=CGMCC 4.7217T=JCM 30349T), respectively.

Streptomyces polygonati sp. nov., an endophytic actinomycete isolated from a root of Polygonatum odoratum (Mill.).

A novel actinomycete, designated strain NEAU-G9T, was isolated from the root of Polygonatum odoratum (Mill.) collected from Harbin, Heilongjiang province, north China, and was characterized using a polyphasic approach. Key morphological and chemotaxonomic properties confirmed the affiliation of strain NEAU-G9T to the genus Streptomyces. Strain NEAU-G9T contained ll-diaminopimelic acid as the diamino acid. The predominant menaquinones were MK-9(H8), MK-9(H6) and MK-9(H4). The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The predominant fatty acids were iso-C16 : 0, anteiso-C15 : 0 and C16 : 0.16S rRNA gene sequence similarity studies showed that strain NEAU-G9T belongs to the genus Streptomyces and exhibits the highest sequence similarity to Streptomyces yanglinensis JCM 13275T (97.75 %). However, phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain NEAU-G9T is most closely related to Streptomyces misakiensis JCM 4062T (97.12 % sequence similarity). A combination of DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-G9T can be clearly distinguished from S. yanglinensis JCM 13275T and S. misakiensis JCM 4062T. Consequently, strain NEAU-G9T represents a novel species of the genus Streptomyces, for which the name Streptomyces polygonati sp. nov. is proposed. The type strain is NEAU-G9T ( = CGMCC 4.7237T = DSM 100521T).

Promicromonospora alba sp. nov., an actinomycete isolated from the cuticle of Camponotus japonicas Mayr.

A novel actinomycete, designated strain 1C-HV12T, was isolated from the cuticle of Camponotus japonicas Mayr and characterized using a polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the organism should be assigned to the genus Promicromonospora and that it forms a monophyletic clade with the closest relatives Promicromonospora umidemergens JCM 17975T(99.17 % 16S rRNA gene sequence similarity), Promicromonospora vindobonensis V45T (98.88 %) and Promicromonospora iranensis HM 792T (98.85 %). Moreover, morphological and chemotaxonomic properties of strain 1C-HV12T also confirmed the affiliation of the isolate to the genus Promicromonospora. The peptidoglycan hydrolysates contained alanine, glutamic acid and lysine, and whole-cell sugars were galactose, glucose, rhamnose and ribose. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified phosphoglycolipid, an unidentified phospholipid and an unidentified glycolipid. The major menaquinones were MK-9(H4) and MK-9(H2). The predominant cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0 and anteiso-C17 : 0. The DNA G+C content was 71.6 mol%. However, the low level of DNA-DNA relatedness and some phenotypic characteristics allowed the isolate to be differentiated from closely related species. Therefore, it is concluded that strain 1C-HV12T represents a novel species of the genus Promicromonospora, for which the name Promicromonospora alba sp. nov. is proposed. The type strain is 1C-HV12T ( = CGMCC 4.7283T = DSM 100490T).

Microbispora camponoti sp. nov., a novel actinomycete isolated from the cuticle of Camponotus japonicus Mayr.

A novel actinomycete, designated strain 2C-HV3(T), was isolated from the cuticle of Camponotus japonicus Mayr collected from Harbin, Heilongjiang province, north China and characterised using a polyphasic approach. The 16S rRNA gene sequence of strain 2C-HV3(T) showed that it has high sequence similarities with Microbispora bryophytorum NEAU-TX2-2(T) (99.9 %), Microbispora amethystogenes JCM 3021(T) (98.9 %) and Microbispora rosea subsp. rosea JCM 3006(T) (98.6 %). Phylogenetic analysis based on 16S rRNA and gyrB gene sequences demonstrated that strain 2C-HV3(T) clusters with M. bryophytorum NEAU-TX2-2(T) using two tree-making algorithms. Moreover, key morphological and chemotaxonomic properties also confirmed the affiliation of strain 2C-HV3(T) to the genus Microbispora. Longitudinal paired spores were observed to be born on short sporophores branching from the aerial hyphae. The cell wall was found to contain meso-diaminopimelic acid as the diagnostic diamino acid; madurose was found in the whole cell hydrolysate. The polar lipid profile was found to consist of diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositolmannoside, ninhydrin-positive glycophospholipids, an unidentified phospholipid and an unidentified glycolipid. The predominant menaquinones were identified as MK-9(H2) and MK-9(H4). The major fatty acids were identified as 10-methyl C17:0 and iso-C16:0. However, a combination of DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain 2C-HV3(T) can be distinguished from its closely related relatives. Consequently, it is proposed that strain 2C-HV3(T) represents a new species of the genus Microbispora, for which the name Microbispora camponoti sp. nov. is proposed. The type strain is 2C-HV3(T) (=CGMCC 4.7281(T) = DSM 100527(T)).

Streptomyces formicae sp. nov., a novel actinomycete isolated from the head of Camponotus japonicus Mayr.

During a screening for novel and biotechnologically useful actinobacteria in insects, a novel actinomycete with antifungal activity, designated strain 1H-GS9(T), was isolated from the head of a Camponotus japonicus Mayr ant, which were collected from Northeast Agricultural University (Harbin, Heilongjiang, China). Strain 1H-GS9(T) was characterised using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of members of the genus Streptomyces. 16S rRNA gene sequence similarity studies showed that strain 1H-GS9(T) belongs to the genus Streptomyces with high sequence similarities to Streptomyces scopuliridis DSM 41917(T) (98.8 %) and Streptomyces mauvecolor JCM 5002(T) (98.6 %). However, phylogenetic analysis based on the 16S rRNA gene sequence indicated that it forms a monophyletic clade with Streptomyces kurssanovii JCM 4388(T) (98.6 %), Streptomyces xantholiticus JCM 4282(T) (98.6 %) and Streptomyces peucetius JCM 9920(T) (98.5 %). Thus, a combination of DNA-DNA hybridization experiments and phenotypic tests were carried out between strain 1H-GS9(T) and the above-mentioned five strains, which further clarified their relatedness and demonstrated that strain 1H-GS9(T) could be distinguished from these strains. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces formicae sp. nov. is proposed. The type strain is 1H-GS9(T) (=CGMCC 4.7277(T) = DSM 100524(T)).

Streptomonospora halotolerans sp. nov., an actinomycete isolated from soil.

A novel actinomycete, designated strain NEAU-Jh2-17(T), was isolated from muddy soil collected from a riverbank in Jilin Province, northern China, and characterized using a polyphasic approach. The 16S rRNA gene sequence of strain NEAU-Jh2-17(T) showed highest similarity to those of Streptomonospora nanhaiensis 12A09(T) (99.26%), Nocardiopsis rosea YIM 90094(T) (97.31%), Streptomonospora halophila YIM 91355(T )(97.24%) and Streptomonospora arabica S186(T) (97.02%). Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strain NEAU-Jh2-17(T) fell within a cluster consisting of the type strains of species of the genus Streptomonospora and formed a stable clade with S. nanhaiensis 12A09(T) in trees generated with two algorithms. Key morphological and chemotaxonomic properties also confirmed the affiliation of strain NEAU-Jh2-17(T) to the genus Streptomonospora. The cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid and whole-cell hydrolysates contained glucose, ribose and galactose. The polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI), phosphatidylinositol mannoside (PIM), two unknown phospholipids (PLs) and two unknown glycolipids (GLs). The predominant menaquinones were MK-10(H2), MK-10(H8), MK-10(H6) and MK-10(H4). Major fatty acids were C18 : 0 10-methyl, anteiso-C17 : 0, C16 : 0 10-methyl, iso-C15 : 0, C17 : 0 10-methyl and C18 : 0. The DNA G+C content was 71.82 mol%. However, a combination of DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-Jh2-17(T) could be distinguished from its closely related relatives. Therefore, strain NEAU-Jh2-17(T) is considered to represent a novel species of the genus Streptomonospora, for which the name Streptomonospora halotolerans sp. nov. is proposed. The type strain is NEAU-Jh2-17(T) ( = CGMCC 4.7218(T) = JCM 30347(T)).

Streptomyces tyrosinilyticus sp. nov., a novel actinomycete isolated from river sediment.

A novel actinomycete, designated strain NEAU-Jh3-20(T), was isolated from river sediment collected from South river in Jilin Province, north China and characterized using a polyphasic approach. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain NEAU-Jh3-20(T) should be assigned to the genus Streptomyces and forms a distinct branch with its closest neighbour Streptomyces vitaminophilus DSM 41686(T)(97.09%). Moreover, key morphological and chemotaxonomic properties also confirmed the affiliation of strain NEAU-Jh3-20(T) to the genus Streptomyces. The cell wall contained ll-diaminopimelic acid and the whole-cell hydrolysates were glucose and ribose. The phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides and an unidentified phospholipid. The predominant menaquinones were MK-9(H8) and MK-9(H6). The major fatty acids were C16 : 0, C18 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The DNA G+C content was 72.2 mol%. A combination of DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-Jh3-20(T) could be distinguished from its closest phylogenetic relative. Therefore, it is proposed that strain NEAU-Jh3-20(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces tyrosinilyticus sp. nov. is proposed. The type strain is NEAU-Jh3-20(T) ( = CGMCC 4.7201(T)= DSM 42170(T)).