Abstract:Cotton Verticillium wilt is the most serious disease affecting cotton cultivation, which could cause a significant decrease in cotton yield or even complete crop failure. Cotton Verticillium wilt is caused by the filamentous fungus Verticillium dahliae. The traditional chemical control affects public health and brings about environmental pollution, and the continuous usage has induced the drug resistance of Verticillium dahliae. Therefore, it is urgent to develop environmental friendly and sustainable development control strategies against cotton Verticillium wilt. Biological control has become a good choice to prevent cotton Verticillium wilt. Based on the analysis of the recent research progress, this review discussed the screening, mechanism of action and field application of biocontrol microbial strains against cotton Verticillium wilt, and summarized the research progress of biocontrol microorganisms inhibiting the growth of pathogen through various mechanisms such as competition, antibiotic action, and inducing plant defense response. Although the application prospects of biocontrol microorganisms are expected, they still face challenges such as environmental adaptability, stability, and usage costs of these biocontrol microorganisms. To further improve the practicality of biocontrol microbial strains in agricultural production, future research should focus on genetic improvement of biocontrol microorganisms, development, and application of the microbial agents and so on.

Abstract:Abstract: [Objective] The aim was to study the action mechanism of analogues BF2-A/B of the antimicrobial peptide BuforinⅡ with Escherichia coli (E.coli) genomic DNA. [Methods] The abruption and binding action of peptides to DNA were investigated by agarose electrophoresis and gel retardation assay, respectively. The change of DNA structure after binding with peptides was researched by circular dichroism spectra. The competitive intercalation of peptides and ethidium bromide (EB) into DNA, and the influence of phosphate anion to the interaction between peptides and DNA were analyzed by fluorescence spectra. [Results] BF2-A/B didn’t breakdown the genomic DNA, but they bond to DNA. Both peptides made the two-helical structure of DNA loose, and impaired the accumulation amongst base pairs. BF2-A/B could weaken the fluorescence intensity of EB-DNA complex, which appeared to inhibit the intercalation of EB into DNA. However, the addition of phosphate anion impaired the fluorescent quenching of peptides to DNA-EB complex. [Conclusion] The initial step of peptides binding to DNA was the adhesion of basic amino acid on phosphate group depended on electrostatic attraction. Then the peptides inserted the groove of DNA duplex. The direct intercalation involving phenylalanine and nucleic acid bases participate in the peptides-DNA interaction. The stronger binding affinity of BF2-B than BF2-A attributed to more positive charge and powerful ability of intercalation into groove and base pair of DNA.

Abstract:Abstract: Co-culturing Bacillus megaterium and Ketogulonigenium vulgare is widely applied to 2-keto-gulonic acid production． For optimizing the process，numerous researchers studied on the symbiotic molecular mechanism of the coculture process． The research was promoted greatly owing to omics technologies，bioinformatics，high throughput technologies and physiology． Recently，the proteomic，metabolomic，comparative genomics and transcriptomics were performed to the research． These omics data provided us the interaction network of the artificial ecosystem in multilevel．Combining with the physiological validation based on the high throughput method，we can elucidate the molecular mechanism in detail，which will facilitate us to develop strategies for metabolic engineering． The paper reviewed the recent developments of symbiotic molecular mechanism research in this co-culture process and its applications． In addition，we propose the future research needs.

Abstract:[Objective] To investigate the action mechanism of scorpion venom peptide Ctry2459 against Candida albicans. [Methods] The broth microdilution and plate count methods were used to determine the minimum inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of Ctry2459 against C. albicans. Time-kill curves were drawn based on the plate count method. In addition, we evaluated the influence of Ctry2459 on the integrity of the cell membrane of C. albicans by propidium iodide (PI) absorption experiment. DNA gel retardation assay was conducted to investigate the binding effect between Ctry2459 and nucleic acid. Also, we measured the effects of Ctry2459 on the reactive oxygen species (ROS) level, mitochondrial membrane potential, and apoptosis/necrosis induction of C. albicans by flow cytometry assays. [Results] The MIC and MFC of Ctry2459 against C. albicans were 25 μg/mL and 50 μg/mL, respectively. Ctry2459 killed C. albicans in a time- and concentration-dependent manner and mainly through membrane disruption, and it could also induce C. albicans necrosis via a ROS-dependent pathway. [Conclusion] Ctry2459 had the potential for the development of anti-C. albicans drugs.

Abstract:In the field of wastewater treatment, algae-bacteria/fungi symbiosis can efficiently remove nitrogen and phosphorus, reduce greenhouse gas emissions, and recycle biomass after sewage treatment. Thus, researchers have shown increasing interests in the mechanisms and applications of algae-bacteria/fungi symbiosis in sewage treatment. There are few articles summarizing the interaction mechanisms of different algae-bacteria/fungi symbiotic systems in sewage treatment. In this review, we introduced the research progress on algae-bacteria/fungi symbiosis, especially the interaction mechanisms and effects, in sewage treatment from the following three aspects:algae-bacteria, algae-fungi, and mixed algae-mixed bacteria. Nutrient exchange is the basis of algae-bacteria/fungi symbiosis in sewage treatment. The molecules involved in signal transduction, such as quorum sensing molecules, can change the behavior and growth of algae or bacteria by activating gene expression or physiological activities. Fungal-assisted bio-flocculation has an immobilization effect on algae. Finally, we proposed the future research directions from the perspectives of mechanism, large-scale application, and biomass recycle.