Fungal community structure analysis of peanut pod rot in soil in Hebei Province,China

In recent years,peanut yield and quality are more seriously affected by pod rot disease in China.However,managing this disease has proven challenging due to the wide host range of its pathogens.In this study,four soil samples were collected from fields with pod rot disease in Hebei Province,and 454 pyrosequencing was used to analyze the fungal communities structure within them.All 38490 ITS high-quality sequences were grouped into 1203 operational taxonomic units,the fungal community diversity of four soil samples was evaluated and compared using Shannon index and Simpson index.The results showed that members of Ascomycota were dominant,followed by Basidiomycota.According to the BLAST results at the species level,Guehomyces had the highest abundance,accounting for about 7.27%,followed by Alternaria,Fusarium,and Davidiella.The relative abundance of Fusarium oxysporum isolated from rotting peanuts in soil with peanut rot was higher than that in the control,indicating that Fusarium oxysporum might be one of the main pathogenic fungus of peanut rot in this area.This study delved into the broader fungal community associated with peanut pod rot,providing a theoretical foundation for preventing and treating this disease in agriculture.

Evaluation of SRAP markers efficiency in genetic diversity of Aspergillus flavus from peanut-cropped soils in China

In order to evaluation the efficiency of SRAP markers on genetic diversity of Aspergillus flavus,we screened out 17sets of primer pairs which could produce clear and reproducible SRAP bands from 150 SRAP primer pairs.The size of SRAP fragments ranged from 120 to 2100 bp.Primer pair Me10/Em9 produced the maximum number of polymorphic bands(12 bands),while Me8/Em13 produced the fewest number of polymorphic bands(only 1).Through analysis genetic diversity ability of different sets of primer pairs,the set of 12 primer pairs was selected for SRAP genetic marker of A.flavus.Cluster analysis was performed based on the genetic similarity coefficients,which ranged from 0.53 to 0.89.A dendrogram assembled using the unweighted pair-group method with arithmetic averages grouped A.flavus samples into 5 main clusters.The results suggested that SRAP marker is a useful molecular technology for the diversity of A.flavus from peanut soils in China.

Developmental toxicity of TCBPA on the nervous and cardiovascular systems of zebrafish (Danio rerio): A combination of transcriptomic and metabolomics

Tetrachlorobisphenol A(TCBPA),a widely used halogenated flame retardant,is frequently detected in environmental compartments and human samples.However,unknown developmental toxicity and mechanisms limit the entire understanding of its effects.In this study,zebrafish(Danio rerio)embryos were exposed to various concentrations of TCBPA while a combination of transcriptomics,behavioral and biochemical analyzes as well as metabolomics were applied to decipher its toxic effects and the potential mechanisms.We found that TCBPA could interfere with nervous and cardiovascular development through focal adhesion and extracellular matrix-receptor(ECM-receptor)interaction pathways through transcriptomic analysis.Behavioral and biochemical analysis results indicated abnormal swimming behavior of zebrafish larvae.Morphological observations revealed that TCBPA could cause the loss of head blood vessels.Metabolomic analysis showed that arginine-related metabolic pathways were one of the main pathways leading to TCBPA developmental toxicity.Our study demonstrated that by using omics,TCBPA was shown to have neurological and cardiovascular developmental toxicity and the underlying mechanisms were uncovered and major pathways identified.

Inhalable oridonin-loaded poly(lactic-co-glycolic)acid large porous microparticles for in situ treatment of primary non-small cell lung cancer

Non-small cell lung cancer(NSCLC) accounts for about 85% of all lung cancers. Traditional chemotherapy for this disease leads to serious side effects. Here we prepared an inhalable oridonin-loaded poly(lactic-co-glycolic)acid(PLGA) large porous microparticle(LPMP) for in situ treatment of NSCLC with the emulsion/solvent evaporation/freeze-drying method. The LPMPs were smooth spheres with many internal pores. Despite a geometric diameter of 10 mm, the aerodynamic diameter of the spheres was only 2.72 mm, leading to highly efficient lung deposition. In vitro studies showed that most of oridonin was released after 1 h, whereas the alveolar macrophage uptake of LPMPs occurred after 8 h, so that most of oridonin would enter the surroundings without undergoing phagocytosis. Rat primary NSCLC models were built and administered with saline, oridonin powder, gemcitabine, and oridonin-loaded LPMPs via airway, respectively. The LPMPs showed strong anticancer effects. Oridonin showed strong angiogenesis inhibition and apoptosis. Relevant mechanisms are thought to include oridonin-induced mitochondrial dysfunction accompanied by low mitochondrial membrane potentials, downregulation of BCL-2 expressions, upregulation of expressions of BAX, caspase-3 and caspase-9. The oridonin-loaded PLGALPMPs showed high anti-NSCLC effects after pulmonary delivery. In conclusion, LPMPs are promising dry powder inhalations for in situ treatment of lung cancer.

Metabolic engineering of Escherichia coli for efficient ectoine production

Ectoine is a high-value stabilizer and protective agent with various applications in enzyme industry,cosmetics,and biomedi-cine.In this study,rational engineering strategies have been implemented in Escherichia coli to efficiently produce ectoine.First,the synthetic pathway of ectoine was constructed in E.coli MG1655 by introducing an artificial thermal switch system harboring the ectABC cluster from Halomonas elongate,and the resulting strain produced 1.95 g/L ectoine.Second,crr encoding the glucose-specific enzyme II domain A of phosphotransferase system and iclR encoding the glyoxylate shunt transcriptional repressor were deleted in E.coli for enhancing the oxaloacetate supply,leading to the increasement of the ectoine titer to 9.09 g/L.Third,thrA encoding the bifunctional aspartokinase/homoserine dehydrogenase was removed from the genome to weaken the competitive pathway;simultaneously,an endogenous feedback-resistant lysC was overexpressed to complement the enzymatic activity deficiency of the aspartate kinase,leading to 30.36%increase of ectoine titer.Next,the expression of phosphoenolpyruvate carboxylase was modulated with varying gradient strength promoters to accelerate the biosynthesis efficiency of ectoine.Finally,aspDH encoding aspartate dehydrogenase from Pseudomonas aeruginosa PAO1 was overexpressed to further improve the biosynthesis of ectoine.The final strain MWZ003/pFT28-ectABC-EclysC^(*)-aspDH-ppc3 produced 30.37 g/L ectoine after 36-h fed-batch fermentation with a yield of 0.132 g/g glucose and a productivity of 0.844 g/(L h).

The Brassicaceae-specific secreted peptides,STMPs,function in plant growth and pathogen defense

Low molecular weight secreted peptides have recently been shown to affect multiple aspects of plant growth,development,and defense responses.Here,we performed stepwise BLAST filtering to identify unannotated peptides from the Arabidopsis thaliana protein database and uncovered a novel secreted peptide family,secreted transmembrane peptides(STMPs).These low molecular weight peptides,which consist of an N-terminal signal peptide and a transmembrane domain,were primarily localized to extracellular compartments but were also detected in the endomembrane system of the secretory pathway,including the endoplasmic reticulum and Golgi.Comprehensive bioinformatics analysis identified 10 STMP family members that are specific to the Brassicaceae family.Brassicaceae plants showed dramatically inhibited root growth uponexposure to chemically synthesized STMP1 and STMP2.Arabidopsis overexpressing STMP1,2,4,6,or 10 exhibited severely arrested growth,suggesting that STMPs are involved in regulating plant growth and development.In addition,in vitro bioassays demonstrated that STMP1,STMP2,and STMP10 have antibacterial effects against Pseudomonas syringae pv.tomato DC3000,Ralstonia solanacearum,Bacillus subtilis,and Agrobacterium tumefaciens,demonstrating that STMPs are antimicrobial peptides.These findings suggest that STMP family members play important roles in various developmental events and pathogen defense responses in Brassicaceae plants.