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White clover (Trifolium repens L.) belongs to the Fabaceae family legume and is cultivated in China for its medicinal properties and ornamental value. White clover is grown around the world for forage, turf , green manure and soil conservation purposes (Zhang el al. 2016). In October 2021, an investigation of a 1,000 m2 plant nursery in Lanzhou, China (36°06'N, 103°83'E) found that 80% of White clover plants were infected, and powdery mildew covered 95% of the leaf area. The disease had seriously destroyed the forage quality and reduced the ornamental value. Initially, thin, radial, irregular white colonies appeared on leaves and gradually spread to stems. The white colonies then expanded and thickened to cover upper surface of the leaf, and microscopic hyphae appeared on the bottom of the leaf. In severe cases, the infection resulted in dieback of the leaf. A small area of sporulating fungus was stripped off from the leaf surface with tape and mounted in sterile water for microscopic examination (Mukhtar et al. 2017). Conidiophores were cylindrical, consisting of a foot cell followed by three to four short cells, measuring 75 to 160 × 7 to 10 μm. Conidiophores had straight, cylindric foot cells ranging from 25 to 40 µm long. Singly produced conidia were hyaline and ranged in shape from oblong to cylindrical. Conidia lacked distinct fibrotic bodies and measured 30 to 45 × 15 to 25 μm in length. Long, unbranched germ tubes formed from the ends of the conidia and nipple-shaped appressoria developed on epiphytic mycelia. Based on these morphological characteristics, the pathogen was initially identified morphologically as Erysiphe polygoni (Braun and Cook 2012). To validate the identity, the internal transcribed spacer (ITS) region of the pathogen (SY77) rDNA was amplified by PCR and sequenced using the ITS1/ITS4 primers (White et al. 1990). The resulting sequences were registered to GenBank (GenBank Accession No.OM280998). The ITS sequence of the SY77 was 100% (640/640) identical to E. polygoni (LC009892) on Polygonum aviculare in the United Kingdom and 99% (638/640) identical to E. polygoni (MK685172) on Antigonon leptopus in Taiwan. MEGA 7.0 was used to conduct the neighbor-joining phylogenetic analysis using the ITS sequences from GenBank. The data indicated that the strain SY77 and E. polygoni clustered together on the same branch. Pathogenicity tests were conducted by gently pressing the infected leaves onto five healthy potted White clover plants, while five non-inoculated plants were used as controls (Michael et al. 2021). The plants were maintained in a growth chamber (25 ℃, 14 h light, and 10 h dark period, RH80%). After 10 days, the inoculated plants developed powdery mildew symptoms, whereas the control plants remained symptom-free. The fungus on the inoculated plants was re-isolated, re-identified, and confirmed as E. polygoni based on morphological observations and molecular identification. There is no previous report on E. polygoni causing powdery mildew on White clover in China. The powdery mildew caused by E. polygoni on Red clover has been reported in China and Bulgaria, respectively (Yuan el al.1991; Galina el al. 2017). To our knowledge, this is the first report of powdery mildew caused by E. polygoni on White clover in China. References: 1. Zheng, L., et al. 2018. Plant Dis. 102:628. 2. Mukhtar, G., et al. 2017. Plant Dis.101:1, 246. 3. Braun, U., and Cook, R. T. A. 2012. Taxonomic Manual of the Erysiphales (Powdery Mildews), CBS Biodiversity Series No.11. CBS, Utrecht. 4. Michael, R. F., et al. 2021.Plant Dis. First look.( doi.org/ 10.1094/PDIS-09-21-2060-PDN). 5. Yuan, Q. H., el al.1991. Pratacult Sci.05:59 (in Chinese). 6. Galina, N., et al, 2017. BIOTECHNOL Anim Husb.33.127.

The prosperity and development of tannery industry have brought about rapid economic growth. However, the tannery landfill without anti-seepage measures in the early stage has generated masses of environmental hazards owing to the lack of awareness in environmental protection. Therefore, it is imperative to pay much attention to the understanding of environmental hazards from tannery waste. In this study, solid samples and groundwater samples were collected from a tannery landfill to study the effect of the characteristic pollutants produced by tanning on chromium distribution with other coexisting substances. The results showed that significant correlations were demonstrated between multiple coexisting substances (total organic carbon, total petroleum hydrocarbons, total nitrogen, Cr, F, Ca, Cu and Pb), indicating the possible same source or they coming from the same tannery production stage. The weights of positive effects and negative effects of coexisting substances on total Cr distribution in the profile decreased in the order: total nitrogen > Cu > Ca > Pb > total organic carbon > F > SO42– > Cd, and Ni > Cl > Hg, respectively. Moreover, the simulation of Visual MINTEQ showed that the cations were mainly bound to Cr as CrO42−, while the anions were bound to Cr3+. This study provided a new perspective on the selection of remediation strategies for Cr-contaminated sites to avoid secondary environmental pollution caused by the release of coexisting heavy metals.

Sludge foaming has been a persistent ailment in worldwide municipal sewage treatment plants (MSTPs). In particular, this problem frequently occurs and lasts throughout the winter and spring season in the sub-plateau MSTPs. Aims to explore the causes of sludge foaming under sub-plateau circumstance, the correlation between the structural and functional changes in bacterial communities and sewage properties was conducted using Illumina high-throughput sequencing technology. The results from 16S rRNA gene sequencing shown that the relative abundances of Actinobacteria (39.5 % ± 4.8 %) and Firmicutes (10.5 % ± 1.0 %) in the foaming sludge were remarkably higher than that in the non-foaming sludge. The abundances of Candidatus Microthrix parvicella (29.8 % ± 6.9 %), Trichococcus (6.5 % ± 1.0 %), and Ornithinibacter (3.5 % ± 0.6 %) were increased after sludge foaming, and which are considered as the dominated foaming-causative bacterial assemblages by the linear discriminant analysis (LDA). Spearman’s correlation analysis and redundancy analysis (RDA) also agreed that lower temperature and dissolved oxygen (DO) levels, higher lipid and protein contents were significantly correlated with sludge foaming. In addition, the predictive functional profiling indicated that the enzymes and their coding genes of the bacterial communities are mainly involved in the fast proliferation and lipid metabolism, and which abundance are highly upregulated during foaming period. These results suggested that the sludge foaming was strongly linked to the Actinobacteria and Firmicutes communities and higher lipid and protein content in the sewage under sub-plateau circumstance. The findings might be important for developing operating strategies to maintain the desired microbial community pattern and improve the performance of MSTPs.

The tannery industry is an integral part of economic development in many developing countries, and the environmental pollution caused by the tannery industry cannot be ignored. In this study, soil and groundwater samples at different depths were collected from an abandoned tannery to investigate the temporal and spatial distribution of characteristic pollutants produced by tanning. The concentrations of Cr, Cl, F and NH4+–N in the soil from the sludge temporary storage area were higher than those from the liming and unhairing workshop, chrome tanning workshop, wastewater outlet, and around wastewater pond. The concentration of Cr(VI) in all sampling sites was below the detection limit. The main species of Cr in the groundwater were Cr(NH3)6Cl2+ and CrO42− based on the simulation of Visual MINTEQ. The saturation index was negative and changed with time indicating that Cr existed in the dissolved phase. The proportion of Cr(VI) to total Cr was negatively correlated with the saturation index in village 1 and village 3. The simulation results from Visual MODFLOW and MT3DMS showed that the migration of Cr, NH4+–N, Cl− and F− mainly occurred in the Quaternary system. The coverage of the pollution plume of pollutants in villages 1 and 3 was as follows: Cr > NH4+−N > Cl− > F−. Two decay rate calculation methods of pollutants with migration time and distance were put forward to provide a basis for the actual investigation of the pollution migration scope and time determination.

Analysis on the concentrations of Pb, Cu in the roots, stems, leaves of phragmites australis which grows on Lingang New City of Shanghai showed that both of Pb, Cu in roots were higher concentrations than that in stems and leaves; the absorption of Pb,Cu had obvious seasonal variation; in winter, the enrichment of Pb, Cu in phranmites autralis was occurred and the enrichment ability of Pb was higher than Cu

Bureau of Science and Technology of Xiamen Municipal Government, China [3502Z20091005]; National Natural Science Foundation of China [40925018]; State Oceanic Administration (SOA) Program [201105021, 201005015]

Rapamycin produced by Streptomyces hygroscopicus displays immunosuppressive, antifungal, anti-tumor, anti-inflammatory and neuro-regenerative properties. To enhance production of rapamycin, aveR, a stimulator in Streptomyces avermitilis, was integrated into the chromosome of S. hygroscopicus TYQ0915. This resulted in a 274.9% increase of rapamycin production in an exconjugant S. hygroscopicus AVH1124. Introduction of aveR acts pleiotropically by affecting growth and sporulation of S. hygroscopicus AVH1124, although aveR is verified to be a pathway-specific regulator in S. avermitilis. This study proved that introduction of a homologous regulatory gene from the same protein family enhanced rapamycin production.

N, N′ -(p-phenyl)-bis-(p-nitro)benzoylthiourea was synthesized and characterized by elemental analysis as well as IR and 1H NMR spectroscopy. The crystal structure of the title compound was determined by single crystal X-ray diffraction. It was crystallized in triclinic space group of P-1, a = 8.1084(12), b = 11.9185(13), c = 12.6061(15) A, α = 62.213(2)°, β = 71.266(2)°, γ = 88.014(3)°, Z = 1, V = 1011.0(2)A 3 . The intramolecular N-H · · · O hydrogen bonding interactions between the N-H and the oxygen atom of C═ O groups suport N, N′ -(p-phenyl)-bis-(p-nitro)benzoylthiourea framework. the solvent DMF molecules are accommodated in the framework by intermolecular N-H · · O hydrogen bonds between N-H and the oxygen atom of DMF in the title compound, which help to assemble into supramolecular structure.

Three new phytane-type diterpene-γ-lactone shaliuin I (2), shaliuin II (3) and shaliuin III (4) were isolated along with thirteen known compounds from twigs of Salix cheilophila omitted (Chinese name "Shaliu", Salicaceae). The structures of three new compounds have been established on the basis of spectroscopic methods and 2D NMR techniques.

Lycopodium japonicumThunb. has attracted great interests due to its rich alkaloids with significant anticancer activity. However, significant chemical differences often exist in a plant species from different geographic origins and affect its quality and bioactivities. Thus, it is urgent to reveal their chemical and biological distinctions at the molecular level. In this context, a comparative chemical analysis of LAs using HPLC-UV-ESI-MS/MS was firstly conducted and resulted in the detection of 46 LAs, 28 of which were identified, and a series of unique LAs markers, such as peaks2,9,10, and11, were further found to be characteristic LAs and selected as markers from four different origins for their quality control. In parallel, the comparative bioactivity assay revealed that the total LAs from Hubei province exhibited much higher inhibitory rate at 65.95% against HepG2 cells than those at 26.72%, 20.26%, and 33.62% for Kenya, Guangxi province, and Zhejiang province in China, respectively. To this end, significant chemical fingerprinting differences and discrepancies in bioactivity of LAs were explored firstly, which could provide valuable information for quality control and further activity studies on LAs from different sources and promote their better pharmaceutical applications in the future as well.

The present study was designed to determine the taxonomic diversity and metabolic activity of the actinomycetes community, including 13 traditional medicinal plants collected in Sichuan province, China, using multiple approaches such as morphological and molecular identification methods, bioactivity assays, and PCR screening for genes involved in antibiotics biosynthesis. 119 endophytic actinomycetes were recovered; 80 representative strains were chosen for 16S rRNA gene partial sequence analyses, with 66 of them being affiliated to genus Streptomyces and the remaining 14 strains being rare actinomycetes. Antimicrobial tests showed that 12 (15%) of the 80 endophytic actinomycetes displayed inhibitory effects against at least one indicator pathogens, which were all assigned to the genus Streptomyces. In addition, 87.5% and 58.8% of the isolates showed anticancer and anti-diabetic activities, respectively. Meanwhile, the anticancer activities of the isolates negatively correlated with their anti-diabetic activities. Based on the results of PCR screening, five genes, PKS-I, PKS-II, NRPS, ANSA, and oxyB, were detected in 55.0%, 58.8%, 90.0%, 18.8% and 8.8% of the 80 actinomycetes, respectively. In conclusion, the PCR screening method employed in the present study was conducive for screening and selection of potential actinomycetes and predicting potential secondary metabolites, which could overcome the limitations of traditional activity screening models.

Nocardia, Rhodococcus and Streptomyces, all members of the actinomycetes family, are Gram-positive eubacteria with high G+C content and able to form mycelium. We report here a newly identified plasmid pXT107 of Nocardia sp. 107, one of the smallest circular plasmids found in Nocardia. The complete nucleotide sequence of pXT107 consisted of 4335 bp with 65% G+C content, and encoded one replication extragenic palindromic (Rep) and six hypothetical proteins. The Rep, double-strand origin and single-strand origin of pXT107 resembled those of typical rolling-circle-replication plasmids, such as pNI100 of Nocardia, pRE8424 of Rhodococcus and pIJ101 of Streptomyces. The Escherichia coli-Nocardia shuttle plasmid pHAQ22, containing the rep gene of pXT107, is able to propagate in Nocardia but not in Streptomyces.

A new cyclohexanone derivative, methyl 5α,6α-epoxy-1-hydroxy-2-methoxy-4-oxocyclohexanacetate, along with five known cyclohexanones were isolated from the aerial parts of Senecio argunensis. Their structures were elucidated on the basis of spectroscopic methods, including IR, EI-MS, HR-ESIMS, 1D NMR and 2D NMR.

An investigation was conducted on the phytoplankton' s community composition, abundance, and their relations with environmental factors in Beixi of Jiulongjiang River, Fujian Province in February (dry season), May (wet season), and October (normal season), 2011. A total of 107 phytoplankton species were identified, belonging to 64 genera and 7 phyla. The dominant species changed with seasons. Campylomonas marssoni and Cyclotella meneghiniana dominated in dry season, Scenedesmus quadricauda and Crucigenia tetrapedia dominated in wet season, and Merismopedia tenuissima dominated in normal season. The phytoplankton's abundance was the highest in dry season (averaged 154.77 x 10(4) cells x L(-1)), followed by in normal season (76.40 x 10(4) cells x L(-1)), and in wet season (45.40 x 10(4) cells x L(-1)). The abundance in dry and normal seasons was significantly positively correlated with water ammonium nitrogen concentration (P0.05) , while that in wet season was significantly positively correlated with water temperature (P0.01). Canonical correspondence analysis (CCA) showed that water temperature was the most important factor affecting the phytoplankton's community structure, and dissolved phosphorous concentration also played important role for the community structure. The CCA ordination plots could well display the phytoplankton' s community structure and its relationships with environmental factors.

A 3-year pot experiment with 8-year continuously cropped greenhouse cucumber soil was conducted to study the effects of different cultivation systems on the soil quality, soil nematode quantity, and crop yields. The third year' s data were taken into analysis. Comparing with traditional cultivation system (two seasons planting cucumber with fallowing in summer) , planting leafy vegetable and garlic in summer increased the yields of the two crops and the soil microbial biomass carbon content, total microbial population, and sucrase activity, decreased the amounts of soil nematode and root-knot nematode, and maintained a relative high Shannon-Weaver index. Planting crown daisy, garlic, and spinach in summer increased soil sucrase activity by 8.9%, 89.5%, and 36.9%, and the planting of crown daisy and garlic also increased the Shannon-Weaver index by 7.7% and 9.4%, respectively. All the results suggested that catching crop and rotation had definite restoration effects on the soil quality under continuously cropping of cucumber, and the effects of planting crown daisy and garlic were more significant.

Community detection is an important methodology for understanding the intrinsic structure and function of a real-world network. In this paper, we propose an effective and efficient algorithm, called Dominant Label Propagation Algorithm (Abbreviated as DLPA), to detect communities in complex networks. The algorithm simulates a special voting process to detect overlapping and non-overlapping community structure in complex networks simultaneously. Our algorithm is very efficient, since its computational complexity is almost linear to the number of edges in the network. Experimental results on both real-world and synthetic networks show that our algorithm also possesses high accuracies on detecting community structure in networks.

Nocardia, Rhodococcus and Streptomyces, all members of the actinomycetes family, are Gram-positive eubacteria with high G+C content and able to form mycelium. We report here a newly identified plasmid pXT107 of Nocardia sp. 107, one of the smallest circular plasmids found in Nocardia. The complete nucleotide sequence of pXT107 consisted of 4335 bp with 65% G+C content, and encoded one replication extragenic palindromic (Rep) and six hypothetical proteins. The Rep, double-strand origin and single-strand origin of pXT107 resembled those of typical rolling-circle-replication plasmids, such as pNI100 of Nocardia, pRE8424 of Rhodococcus and pIJ101 of Streptomyces. The Escherichia coli-Nocardia shuttle plasmid pHAQ22, containing the rep gene of pXT107, is able to propagate in Nocardia but not in Streptomyces.

A gene replacement/disruption system of Amycolatopsis mediterranei U32 was developed based on the established electroporation conditions as well as appropriate selective markers. Through two-step selection, ahbas gene in U32 was replaced by a promoterless alpha-amylase gene constructed on the plasmid pDK110 of E. coli. The first single-crossover and the second double-crossover frequencies were approximately 0.5%-0.7% and 2%, respectively. Denaturation of the plasmid pDK110 increased the integration frequency about 7-10 folds, while electric shock treatment of the single-crossover recombinants increased the frequency of second crossover recombination about 5 folds. Employing denatured DNA fragments containing an apramycin-resistance gene flanked with regions of the respective genes, One-step disruption of rifO and amrA genes of U32 was also achieved with an efficiency of 30-50 transformants per microgram of DNA.

The title compound, [Ag(C(7)H(4)ClO(2))(C(6)H(8)N(2))(2)], is a mononuclear silver(I) complex. The Ag(I) atom is three-coordinated by two pyridine N atoms from two 5-methyl-pyridin-2-ylamine ligands and by one O atom of a 4-chloro-benzoate ligand, forming a distorted T-shaped coordination. In the crystal structure, the mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains running along the b axis.

In the title complex, [Zn(C(3)H(3)O(2))(C(27)H(27)N(7))](ClO(4))·C(3)H(7)NO·1.5CH(4)O, the Zn(II) ion is five-coordinated by four N atoms from a tris-(1-methyl-benzimidazol-2-ylmeth-yl)amine (Mentb) ligand and one O atom from an acrylate ligand in a distorted trigonal-bipyramidal geometry with approximate mol-ecular C(3) symmetry. The atoms of the acrylate ligand are disordered over two sites, with approximate occupancies of 0.84 and 0.16. In addition, a methanol solvent mol-ecule is disordered over two sites with equal occupancies. In the crystal structure, the full-occupancy methanol is linked to a dimethyl-formamide mol-ecule by an inter-molecular O-H⋯O hydrogen bond.