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Staphylococcus haemolyticus (S. haemolyticus) is the second most commonly isolated coagulase-negative staphylococcus (CoNS) in patients with hospital-acquired infections. It can produce phenol-soluble modulin (PSM) toxins and form biofilms. Compared with the wealth of information on Staphylococcus aureus and Staphylococcus epidermidis, very little is known about S. haemolyticus. There is an urgent need to find an effective preparation to combat the harm caused by S. haemolyticus infection. Chinese herbs have been utilized to cure inflammation and infectious diseases and have a long history of anticancer function in China. Here, we modified fusaric acid characterized from the metabolites of Gibberella intermedia, an endophyte previously isolated from Polygonum capitatum. This study shows that fusaric acid analogs (qy17 and qy20) have strong antibacterial activity against S. haemolyticus. In addition, crystal violet analyses and scanning electron microscopy observations demonstrated that qy17 inhibited biofilm formation and disrupted mature biofilms of S. haemolyticus in a dose-dependent manner. Additionally, it reduced the number of live bacteria inside the biofilm. Furthermore, the antibiofilm function of qy17 was achieved by downregulating transcription factors (sigB), transpeptidase genes (srtA), and bacterial surface proteins (ebp, fbp) and upregulating biofilm-related genes and the density-sensing system (agrB). To further elucidate the bacteriostatic mechanism, transcriptomic analysis was carried out. The following antibacterial mechanisms were uncovered: (i) the inhibition of heat shock (clpB, groES, groL, grpE, dnaK, dnaJ)-, oxidative stress (aphC)- and biotin response (bioB)-related gene expression, which resulted in S. haemolyticus being unable to compensate for various stress conditions, thereby affecting bacterial growth; and (ii) a reduction in the expression of PSM-beta (PSMβ1, PSMβ2, PSMβ3) toxin- and Clp protease (clpP, clpX)-related genes. These findings could have major implications for the treatment of diseases caused by S. haemolyticus infections. Our research reveals for the first time that fusaric acid derivatives inhibit the expression of biofilm formation-related effector and virulence genes of S. haemolyticus. These findings provide new potential drug candidates for hospital-acquired infections caused by S. haemolyticus.

In May 2017, the Innovative Integration and Demonstration of Green and Efficient Agricultural Technology in Danjiangkou Water Conservation Area, belonging to the Cooperative Innovation Project of Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences, was officially launched. The aim of the cooperative project was to tackle problems in green and efficient agricultural production, planting and breeding coupling, ecological cycling, non-point source pollution control, and multi-functional rural ecosystem construction. In accordance with the ideas of single technology standardization, composite technology integration, and systematic technology systematization, the cooperative project innovatively integrated 10 key technologies that refer to the utilization of biodiversity, adjustment of agricultural planting structure, green and efficient production of main agricultural products in the whole industrial chain, new pattern of planting and breeding cycle, highly effective ecological facility agriculture, and rural domestic pollutant control in Danjiangkou. We have summarized and provided a comprehensive technical solution for green and efficient agriculture in a water conservation area, which can be copied and extended experience and used as a demonstration model for similar areas. The achievements of this project will provide effective scientific and technological support for water quality and safety in the South-to-North Water Diversion, promote green development of agriculture, increase farmer income, and alleviate poverty in water conservation areas.

To clarify the ecological adaptability of the invasive plant Flaveria bidentis to heavy metal-contaminated habitats, we simulated habitats with different concentrations of cadmium(Cd)by pot experiments, and the plasticity of responses of growth, and physiological and ecological characteristics as well as heavy metal enrichment characteristics in response to the environmental stress were studied. Additionally, the tolerance mechanisms of plant were further explored. The results showed that high concentration heavy metal treatment(8 mg·kg-1)significantly inhibited the growth and biomass of Flaveria bidentis, both of which showed a decreasing trend with the increase of Cd concentration; The content of malondialdehyde(MDA)and the fluorescence intensity of DCF increased gradually with the increase of Cd concentration, which indicated the active oxygen content increased. Under low(2 mg·kg-1)and medium(4 mg·kg-1)concentrations of cadmium, the Flaveria bidentis reduced its active oxygen content by increasing superoxide dismutase(SOD), peroxidase(POD)and catalase (CAT)activities. However, the activities of antioxidant enzymes decreased under the high concentration(8 mg·kg-1)treatment; The content of Cd in the tissues of Flaveria bidentis showed the rule of root > leaf > stem. With the increase of Cd concentration, the content of heavy metals in the tissues increased gradually, and the Cd concentration and transfer coefficient in the roots and aboveground parts increased first and then decreased. Under heavy metal stress, the phenotypic plasticity index(PPI)of root biomass, leaf biomass and heavy metal enrichment of Flaveria bidentis was higher(>0.5),which indicated that Flaveria bidentis may accumulate nutrients mainly through root and leaf biomass processes, and regulate the enrichment and transfer of heavy metals in the body to adapt to heavy metal polluted habitats.

In order to provide a theoretical basis for ecological management model in an orchard, we investigated the characteristics of soil microbial community composition under cover crop treatments in a kiwifruit orchard in the water source conservation area of Danjiangkou. We used the phospholipid fatty acid(PLFA)method to analyze the effects of different treatments(T1:Cover crop left on soil after cutting; T2:Cover crop and removed after cutting; CK:Clean tillage)on soil microbial community structure. The results showed that the total PLFAs, microbial biomass carbon, and nitrogen of cover crop treatments(T1 and T2)were significantly higher than that of CK(P

Farmland management measures can have a significant impact on the carbon cycle of farmland ecosystems, which can affect soil fertility, agricultural production, and food security, and more broadly, climate change and environmental health. In this paper, the effects of different farmland management measures(fertilization methods, planting systems, and farming models)on soil organic carbon, greenhouse gas emissions, and soil microorganisms were reviewed. The increase in soil organic carbon was fastest when organic and inorganic fertilizer were applied. Moreover, there was a threshold effect between the amount of fertilizer applied and the soil carbon inventory. The application of organic fertilizer increased the CO2 emissions flux in the soil, and the application of phosphorus and potassium fertilizers reduced the globe warming potential of farmland soil more than nitrogen fertilizer. Increasing the application ratio of organic fertilizer to phosphate fertilizer was beneficial, leading to an increase in microbial richness in the soil and accumulation of microbial biomass carbon. Planting structure and planting density both affected the carbon storage of farmland soil, and planting structure had a significant impact on greenhouse gas emissions in farmland ecosystems. Compared with traditional monoculture planting, crop rotation and intercropping could effectively reduce the greenhouse gas emissions of farmland. At the same time, crop rotation was more conducive to increasing soil microbial diversity than continuous cropping. Conservation tillage improved the efficiency of farmland soil carbon, reduced greenhouse gas emissions, and had a positive impact on microbial activity, diversity, community structure, and carbon source utilization. Finally, we summarized the application of international mainstream carbon models to farmland ecosystems, and present future development prospects.

As one of the epigenetic modifications, DNA methylation has become ubiquitous in plant genome DNA. It not only plays an important role in rapid adaptation to new environments but also participates in the process of plant growth and organ differentiation. In this study, we constructed an optimized MSAP system to analyze the methylation variation characteristics of different organs at different developmental stages of the same organs of Flaveria bidentis. The results showed that the organ-specific MSAP system amplified 536 bands by using 13 pairs of primers, in which the primer EhHM7 made the greatest contribution to epigenetic diversity, and the percentage of polymorphism was 92.45%. The developmental stage-specific MSAP system amplified 407 bands by using 14 pairs of primers, in which EcHM1 had the greatest contribution to epigenetic diversity, and the percentage of polymorphism was 80.56%. The results of varying themethylation type showed that there were significant differences in methylation levels among the different organs (roots, stems, and leaves)at different developmental stages of the same organs (old leaves and young leaves), among the three methylation variants of hemi-methylation, full methylation, and overall methylation, the methylation rate of the stem tissue was the highest, reaching 30.28%, 19.37% and 49.66%, respectively.The full-methylated and overall methylated rate of the old leaf tissue were significantly higher than those of the young leaf tissue, reaching 33.29% and 52.77%, respectively.The principal component analysis showed that the individual distribution of leaves of Flaveria bidentis were more intensive than that of roots and stem organs, and the young leaves were denser than the old leaves, which indicated that there were larger differences between individual roots and stems. This individual difference was greater than that of the leaves of Flaveria bidentis, and the individual difference of old leaves were greater than that of young leaves, which could not be ignored during sample collection. Therefore, during the studies on the invasiveness of Flaveria bidentis by using epigenetic methods, it is necessary to formulate a scientific sampling plan and consider plant organ and growth stage specificity as important factors.

The addition of temozolomide (TMZ) to radiotherapy (RT) improves survival of patients with glioblastoma (GBM). However, TMZ + RT causes excess toxicity in patients. In this study, we prepared angiopep-2 (A2) modified lipid-poly (hypoxic radiosensitized polyprodrug) nanoparticles for TMZ delivery (A2-P(MIs)25/TMZ) to achieve synergistic effects against glioma. This A2-P(MIs)25/TMZ display highly promising advantages: (1) a hydrophobic P-(MIs)25 core where poorly water-soluble TMZ can be encapsulated; (2) nitro groups of the hydrophobic P-(MIs)25 core that are converted into hydrophilic amino groups (P(NH2s)25) under low oxygen conditions to mimic the oxygen-increased sensitization to RT; (3) a lipid monolayer at the interface of the core and the shell to modify the A2 (a specific ligand for low-density lipoprotein receptor-related protein-1 (LRP-1), which are expressed in the blood-brain barrier (BBB) and human glioma cells), thereby enhancing the drug encapsulation efficiency in glioma. These nanoparticles appear as a promising and robust nanoplatforms for TMZ and hypoxic cell radiosensitization delivery.