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AMPA receptors (AMPARs) mediate the majority of excitatory transmission in the brain and enable the synaptic plasticity that underlies learning1. A diverse array of AMPAR signalling complexes are established by receptor auxiliary subunits, which associate with the AMPAR in various combinations to modulate trafficking, gating and synaptic strength2. However, their mechanisms of action are poorly understood. Here we determine cryo-electron microscopy structures of the heteromeric GluA1–GluA2 receptor assembled with both TARP-γ8 and CNIH2, the predominant AMPAR complex in the forebrain, in both resting and active states. Two TARP-γ8 and two CNIH2 subunits insert at distinct sites beneath the ligand-binding domains of the receptor, with site-specific lipids shaping each interaction and affecting the gating regulation of the AMPARs. Activation of the receptor leads to asymmetry between GluA1 and GluA2 along the ion conduction path and an outward expansion of the channel triggers counter-rotations of both auxiliary subunit pairs, promoting the active-state conformation. In addition, both TARP-γ8 and CNIH2 pivot towards the pore exit upon activation, extending their reach for cytoplasmic receptor elements. CNIH2 achieves this through its uniquely extended M2 helix, which has transformed this endoplasmic reticulum-export factor into a powerful AMPAR modulator that is capable of providing hippocampal pyramidal neurons with their integrative synaptic properties. Analyses of AMPA receptor–auxiliary subunit complexes provide insights into the gating and modulation of the AMPA receptor by TARP-γ8 and CNIH2.

Biliary-stent implantation has become an effective treatment for patients with malignant obstructive jaundice caused by hepatobiliary carcinoma. Stent restenosis due to tumor ingrowth is a common problem. In this study, we assessed a biodegradable form of magnesium (Mg) for its anticancer effect on hepatobiliary carcinoma, compared to the conventional stent material of titanium (Ti). The results showed that a Mg extract inhibited proliferation and induced apoptosis in human cholangiocarcinoma cells, while a Mg plate inhibited cell adhesion and destroyed the cytoskeleton in the process of biodegradation. In animal experiments with H22 tumor-bearing mice, Mg wires implanted in tumors exhibited an inhibitory effect on their growth compared with Ti wires. Fifteen days after implantation of metal wires, the mean tumor volume and weight in the Mg group were significantly smaller than in the Ti group. We observed the dynamic-degradation process of Mg wires in tumors and generation of H2 gas via soft X-ray photography and scanning electron microscopy. Histopathological analyses showed that apoptosis of tumor cells around Mg wires significantly increased, expression of carbonic anhydrase 9 significantly decreased, and the upstream protein hypoxia-inducible factor 1-alpha also decreased to some extent. Taken together, these results indicated that biodegradable Mg had antitumor properties both in vitro and in vivo, suggesting its potential application as a novel material for biodegradable biliary stents.

Three-dimensional (3D) Ag–ZnFe2O4-reduced graphene oxide (rGO) was successfully synthesized using a hydrothermal and photo-reduction method, and the morphological differences of the materials were observed. Their photocatalytic activity was evaluated by photocatalytic degradation of enrofloxacin (ENR) under visible-light irradiation. The results indicated that Ag–ZnFe2O4–rGO exhibited superior photocatalytic properties and good stability. In this research, the enhancement of photocatalytic performance is mainly attributed to the electron channelization ability of rGO, which traps the photoexcited electrons of ZnFe2O4 on its π framework, and reduces the electron–hole recombination rate. Moreover, the high surface area of 3D pompon mum flower-like ZnFe2O4 provides more reactive sites. In addition, free radical capture and ESR experiments as well as pathway analysis of degradation also confirmed that superoxide radicals (˙O2−) and photo-generated holes from Ag–ZnFe2O4–rGO were the main active species in the degradation progress of ENR.

SPARC is a cysteine-rich acidic secreted protein. It is a non-collagen component of bone, which is widely distributed in humans and animals and plays an important role. SPARC has been found in a variety of human cancers (breast cancer, stomach cancer, ovarian cancer, etc.) and diabetes-related research. Especially the muscle and fat metabolism are closely related. In this study, we used a DNA pool to detect a new SNP site (g.12454T > C). A total of 616 samples of four breeds of Qinchuan cattle (QC, n=176), Xianan cattle (XN, n=160), Pinan cattle (PN, n=136) and Jiaxian cattle (JX, n=144) were analyzed and identified with ARMS-PCR. In addition, we correlated SNP with growth traits and showed significant correlation with growth traits such as rump length, hip width, and body length (p

Two new octa-coordinated ternary europium(III) complexes of the type [Eu(btfa)3(Br2-bpy)] (Eu-1) and [Eu(btfa)3(PhE2-bpy)] (Eu-2) (where btfa = 4,4,4-trifluoro-1-phenyl-1,3-butanedione, Br2-bpy = 5,5′-dibromo-2,2′-bipyridine, PhE2-bpy 5,5′-bis(phenylethynyl)-2,2′-bipyridine) together with a previously reported complex [Eu(btfa)3(bpy)] (Eu-3) have been synthesized. The complexes have been characterized by analytical and spectroscopic methods. The photophysical properties of the complexes have also been analyzed both experimentally and theoretically. The contribution of each ligand to the sensitized Eu(III) photoluminescence (PL) has been analyzed and is discussed. An energy transfer (ET) mechanism is proposed and discussed for the sensitized Eu(III) emission using experimental and theoretical data. The Eu(III) complex incorporating the parent bpy showed impressive performance as a double-emitting layer (EML) red organic light emitting diodes (R-OLEDs).

A novel Gram-stain-negative, strictly aerobic bacterium that has a rod-like shape with a single polar flagellum in the exponential phase of growth and a spherical or ovoid shape without a flagellum in the stationary phase was isolated from a mangrove wetland sediment sample collected at Beilun Estuary National Nature Reserve, Guangxi Province, PR China and designated strain ZS-4T. This strain grew optimally at pH 6.0–8.0, at a temperature of 37 °C and in the presence of 3–4 % (w/v) NaCl. Its polar lipid profile included phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid and two uncharacterized lipids. Ubiquinone 8 (Q-8) was the sole respiratory quinone and the cellular fatty acids were dominated by C17 : 1ω8c and C16 : 0. A phylogenetic analysis based on the 16S rRNA gene sequence showed that strain ZS-4T exhibited its highest similarities to the type strains Thalassotalea litorea HMF4135T (97.8 %) and Thalassotalea ponticola GJSW-36T (95.9 %). A whole genome-level comparison of strain ZS-4T with T. litorea MCCC 1K03283T revealed an average nucleotide identity value of 75.6 % and a calculated DNA–DNA hybridization value of 19.6 %. In addition, the genomic DNA G+C content of strain ZS-4T was 45.9 mol%. Thus, based on analyses of its morphology, physiology, fatty acid composition and 16S rRNA gene sequence, strain ZS-4T should be considered a novel species of the genus Thalassotalea , with the proposed name Thalassotalea mangrovi sp. nov. The type strain is ZS-4T (=KCTC 72399T=MCCC 1K03630T).

As a high-efficiency energy storage and conversion device, lithium-ion batteries have high energy density, and have received widespread attention due to their good cycle performance and high reliability. However, currently commercial lithium batteries usually use organic solutions containing various lithium salts as liquid electrolytes. In practical applications, liquid electrolytes have many shortcomings and shortcomings, such as poor chemical stability, flammability, and explosion. Therefore, the liquid electrolyte has a great safety hazard. The use of solid electrolyte ensures the safety of lithium-ion batteries, and has the advantages of high energy density, good cycle performance, long life, and wide electrochemical window, making the battery safer and more durable, with higher energy density and simple battery Structural design. Solid electrolytes mainly include inorganic solid electrolytes and organic polymer solid electrolytes. Although both inorganic solid electrolytes and polymer solid electrolytes have their own advantages, as far as the existing research work is concerned, whether it is an inorganic system or a polymer system, a single-system solid electrolyte can never achieve the full performance of an ideal solid electrolyte. The composite solid electrolyte composed of active or passive inorganic filler and polymer matrix is considered as a promising candidate electrolyte for all-solid-state lithium batteries. Among many polymer systems, PEO-based is considered to be the most ideal polymer substrate. In this review article, we first introduced the structure, properties, and preparation methods of PEO-based polymer electrolytes. Furthermore, the researches related to the modification of PEO-based polymer solid electrolytes in recent years are summarized. The contribution of polymer structural modification and the introduction of additives to the ionic conductivity, electrochemical stability and mechanical properties of PEO-based solid electrolytes is described. Examples of different composite solid electrolyte design concepts were extensively discussed, such as inorganic inert nanoparticles/PEO, oxide/PEO, and sulfide/PEO. Finally, the future development direction of composite solid electrolytes was prospected.

Nortriterpenoids isolated from Walsura cochinchinensis have attracted much attention from both synthetic and medicinal chemists, yet only recently have efficient synthetic approaches to any members appeared. Shown here is that the common intermediate with a 6/6/5/6-fused tetracyclic ring nucleus can be converted to walsucochin family members. The first total syntheses of (±)-walsucochin A, (±)-walsucochinoids C-F, and their analogues were achieved in this work.

Microcystis aeruginosa can cause harmful algal blooms in freshwaters worldwide. It has already seriously affected human lives and prevented the use of water resources. Therefore, there is an urgent need to develop ecofriendly and effective methods to control and eliminate M. aeruginosa in aquatic environments. In this study, Halobacillus sp. strain H9, a bacterium that showed high M. aeruginosa flocculation activity, was isolated and selected to assess its potential for the removal of M. aeruginosa. The analyses of flocculation activity and mode indicated that the strain H9 induced M. aeruginosa flocculation by secreting active flocculating substance rather than by directly contacting algal cells. A 5% concentration of the H9 supernatant could efficiently flocculate M. aeruginosa cells with a density of up to 5 × 107 cells/mL. Dramatic increases in the zeta potential indicated that charge neutralization could be the mechanism of the flocculation process. The strain H9 flocculated M. aeruginosa with no damage to the algal cell membrane, and did not result in microcystin being released into the surrounding environment. The flocculated algal culture was less toxic to zebrafish larvae, suggesting an environmentally friendly benefit of the H9 supernatant. In addition to M. aeruginosa, the H9 strain was also able to flocculate two other species causing harmful algal blooms, Phaeocystis globose and Heterosigma akashiwo. Furthermore, the flocculation activity of the H9 supernatant was stable at different temperatures and over a wide pH range. These characteristics give the H9 strain great potential for mitigating the influences of harmful algal blooms.

Based on target DNA (tDNA)-mediated proximity binding to develop unique DNA assembly as output translator and enzyme-cleaved recycle for signal amplification, an electrochemical impedimetric biosensor is developed. The DNA assembly is constructed by the proximal ligation of tDNA with two affinity probes (A1 and A2) on Au-Fe3O4 magnetic microspheres as substrate previously conjugated with A1, DNA linker (L1) and DNA transduction probe (TP). This binding brings the domain C2* of A2 close to the formed dsDNA TP:L1, facilitating the displacement of TP by C2* (C2*:L1). Under the T7-powered catalysis, the cleavage reaction, C2* liberation and next displacement of TP are initiated and successively recycled. In response to a single-target binding event, hundreds of output TP are released and are recognizable to hairpin DNA (NH2-HP) modified in the electrode surface. After exonuclease III (ExoIII) catalyzing the cleavage recycle, the retained C-rich repeats are converted into stable i-motif configuration when decreasing pH, generating decreased electron transfer impedance (Ret) owing to increased electrostatic attraction to [Fe(CN)6]3−/4−. Thus, the impedimetric biosensor is highly specific and sensitive with a limit of detection of 31 fM. This strategy would be promising to open up a new analytical route for disease diagnosis and bioanalysis.

The heme‐copper oxidase superfamily comprises cytochrome c and ubiquinol oxidases. These enzymes catalyze the transfer of electrons from different electron donors onto molecular oxygen. A B‐family cytochrome c oxidase from the hyperthermophilic bacterium Aquifex aeolicus was discovered previously to be able to use both cytochrome c and naphthoquinol as electron donors. Its molecular mechanism as well as the evolutionary significance are yet unknown. Here we solved its 3.4 Å resolution electron cryo‐microscopic structure and discovered a novel dimeric structure mediated by subunit I (CoxA2) that would be essential for naphthoquinol binding and oxidation. The unique structural features in both proton and oxygen pathways suggest an evolutionary adaptation of this oxidase to its hyperthermophilic environment. Our results add a new conceptual understanding of structural variation of cytochrome c oxidases in different species., The 3.4 Å structure of cytochrome c oxidase from the hyperthermophilic bacterium Aquifex aeolicus (AaCcO) has been solved. The molecular mechanism that AaCcO uses involves both cytochrome c and quinol as electron donors through the native quinol molecules (NQs) bound at the dimeric interface.

AMPA glutamate receptors (AMPARs) mediate the majority of excitatory transmission in the brain, and enable synaptic plasticity that underlies learning 1. A diverse array of AMPAR signaling complexes are established by receptor auxiliary subunits, associating in various combinations to modulate trafficking, gating and synaptic strength 2. However, their mechanisms of action are poorly understood. Here, we determine cryo-electron microscopy structures of the heteromeric GluA1/2 receptor assembled with both TARP-γ8 and CNIH2, the predominant AMPAR complex in the forebrain, in both resting and active states (at 3.2 and 3.7 Å, respectively). Consequential for gating regulation, two γ8 and two CNIH2 subunits lodge at distinct sites beneath the ligand-binding domains of the receptor tetramer, with site-specific lipids shaping each interaction. Activation leads to a stark asymmetry between GluA1 and GluA2 along the ion conduction path, and an outward expansion of the channel triggers counter-rotations of both auxiliary subunit pairs, that promotes the active-state conformation. In addition, both γ8 and CNIH2 pivot towards the pore exit on activation, extending their reach for cytoplasmic receptor elements. CNIH2 achieves this through its uniquely extended M2 helix, which has transformed this ER-export factor into a powerful positive AMPAR modulator, capable of providing hippocampal pyramidal neurons with their integrative synaptic properties.

Total syntheses of (±)-walsucochin B and (±)-walsucochinoids M and N have been achieved from farnesyl bromide. The key steps of the synthetic sequence are the titanocene-mediated radical cyclization and base-induced cycloaromatization for the rapid construction of the 6/6/5/6-fused tetracyclic skeleton. Importantly, a Cu-mediated remote C-H hydroxylation reaction has been developed to site-selectively install the oxygen function at the C-7 position of the target molecules, thus solving the biggest challenge for the synthesis of the compounds.

Mammalian mitochondrial inner membrane fusion is mediated by optic atrophy 1 (OPA1). Under physiological conditions, OPA1 undergoes proteolytic processing to form a membrane-anchored long isoform (L-OPA1) and a soluble short isoform (S-OPA1). A combination of L-OPA1 and S-OPA1 is essential for efficient membrane fusion; however, the relevant mechanism is not well understood. In this study, we investigate the cryo-electron microscopic structures of S-OPA1–coated liposomes in nucleotide-free and GTPγS-bound states. S-OPA1 exhibits a general dynamin-like structure and can assemble onto membranes in a helical array with a dimer building block. We reveal that hydrophobic residues in its extended membrane-binding domain are critical for its tubulation activity. The binding of GTPγS triggers a conformational change and results in a rearrangement of the helical lattice and tube expansion similar to that of S-Mgm1. These observations indicate that S-OPA1 adopts a dynamin-like power stroke membrane remodeling mechanism during mitochondrial inner membrane fusion.

The design of alumina-magnesia castables was optimized based on the action mechanism of raw materials. In this study, the effects of fine reactive alumina powders on the properties of alumina-magnesia castables with TiO2 additions were investigated. The phase composition and microstructure of castables with different contents of TiO2 and two fine reactive alumina powders were characterized by X-ray diffraction and scanning electron microscopy. The results of these studies showed that the Na2O/SiO2 ratio of reactive alumina affected on the phase evolution and properties of castables. The changes in the spinel and CA6 content and their solid solubility could account for the comprehensive effect of TiO2 and reactive alumina on the castables. The difference in the expansion of castables with 1 wt% TiO2 addition after calcination at 1350 °C was significant. The permanent linear changes and the apparent porosity of castables first increased and then decreased with increasing the calcination temperature. Castables containing reactive alumina with lower Na2O/SiO2 ratio had higher cold moduli of rupture.

Proximity binding-induced DNA assemblies possessing outstanding flexibility and diversity can provide great accessibility for output translation of amplifiable DNA probes or directly detectable signals. Based on a novel protein-responsive DNA assembly constructed via proximity binding-initiated rolling circle amplification (RCA), we present a sensitive and specific fluorescence resonance energy transfer (FRET) strategy for the immunoassay of mucin 1 (MUC1). The resultant RCA product containing numerous and continuous repeats as the tandem template accelerates the transduction of signal probes through the disassembly of triple-helix stem structure (THSS), achieving a significantly amplified FRET signal readout.

A new tris β-diketonate europium(III) complex [Eu(btfa)3Py-Im] (Eu-1) (4,4,4-trifluoro-1-phenyl-1,3-butanedione (btfa) and 2-(2-pyridyl)benzimidazole (Py-Im)] has been synthesized and structurally characterized. A single crystal X-ray diffraction analysis shows that Eu-1 is octacoordinated and the coordination sphere is composed of a EuO6N2 core with a trigonal dodecahedral (D2d) geometry. The photophysical properties of Eu-1 were analysed in detail and with the help of the experimental PL data and theoretical modelling, energy transfer rates were calculated, and an energy transfer mechanism is proposed for Eu-1. The complex has been used as the emitting layer (EML) to fabricate organic light emitting diodes (OLEDs). Eight OLEDs, of which four single-EML and four double-EML with varying doping concentration, were fabricated via a thermal evaporation method using Eu-1 as the EML. Under the optimum conditions a highly monochromatic bright red emission (CIEx,y = 0.640, 0.311) with brightness (B) = 896 cd/m2, current efficiency (ηc) = 2.26 cd/A, power efficiency (ηp) = 1.92 lm/W and external quantum efficiency (EQE) = 1.6% at very low Vturn-on = 3.4 V was obtained.

Glyphosate and glufosinate ammonium are the main herbicides used to control weeds in no-tillage agricultural fields in China. However, their leaching risk to groundwater and ecological risk to aquatic organisms remain unclear. From the agricultural basins among 10 provinces of China, glyphosate, its main metabolite aminomethylphosphonic acid (AMPA), and glufosinate ammonium were detected in 1.01%, 0.86%, 0% of 694 groundwater samples with the maximum concentrations of 2.09, 5.13, and

A programmed dual-functional DNA tweezer (DFDT) as a signaling molecule is reported for the simultaneous and recognizable fluorescence detection of microRNA 21 (miRNA 21) and mucin 1 (MUC1). This unique DFDT is assembled from two Au-NP-attached central strands (C1 and C2) and an arm strand (A) dually ended by fluorophores Cy3 and Cy5, which are spatially separated from Au NP in the originally opened state. Through the competitive affinity interaction between targets and their complementary and aptamer sequences tethered in two recognition strands (R1 and R2), miRNA 21 and MUC1 are respectively converted into two dependently displaced fuel strands (F1 and F2). The next hybridization with two pairs of unpaired segments overhung in open DFDT leads to its conformational closure, resulting in the approach of Cy3 and Cy5 to Au NP. On the basis of the nanometal surface energy transfer scheme, the fluorescence emission of Cy3 or Cy5 is cooperatively quenched by Au NPs attached in C1 and C2. The significant variation of fluorescence intensity enables one-step, cost-effective, and specific quantization of miRNA 21 and MUC1 with high sensitivity down to 32 fM and 2.6 fg·mL-1 (8.5 pM), respectively. The novel DFDT-based assay route of multiplex analytes is promising and has the potential for rapid and reliable diagnosis and treatment of cancer-related diseases.

Mammalian mitochondrial inner membrane fusion is mediated by OPA1(optic atrophy 1). Under physiological condition, OPA1 undergoes proteolytic processing to form a membrane-anchored long isoform (L-OPA1) and a soluble short isoform (S-OPA1). A combination of L-OPA1 and S-OPA1 are required for membrane fusion, however, the relevant mechanism is not well understood. In this study, we investigate the cryo-EM structures of S-OPA1 coated liposome at nucleotide-free and GTPγS bound states. S-OPA1 exhibits a general structure of dynamin family. It can assemble onto membrane in a helical array with a building block of dimer and thus induce membrane tubulation. A predicted amphipathic helix is discovered to mediate the tubulation activity of S-OPA1. The binding of GTPγS triggers a conformational rotation between GTPase domain and stalk region, resulting the rearrangement of helical lattice and tube expansion. This observation is opposite to the behavior of other dynamin proteins, suggesting a unique role of S-OPA1 in the fusion of mitochondrial inner membrane. SIGNIFICANCE STATEMENT Mitochondria are highly dynamic cellular organelles that constitute a remarkably dynamic network. Such dynamic network is vital to keep homeostasis of cellular metabolism and it is balanced by fission and fusion events. Having the double membrane, the fusion of mitochondria becomes more complicated in comparison with other cellular mono-membrane organelles. The inner membrane fusion is driven by OPA1 that needs to be pre-processed to long and short forms while the molecular mechanism is largely unknown. This work well characterizes the biochemical property of the short form of OPA1, and reveals how it interacts with membrane and how its conformation responds to nucleotide binding. This work gives a further insight into mitochondrial inner membrane fusion mechanism.

We prepared a series of amino-functionalized organic-inorganic hybrid silica materials by post-modification (SBA-15-N) and one-pot (SS-0.5h-N) methods with different molar rate of APTES/SS (0.1:1, 0.2:1, 0.3:1, 0.5:1), and then took salicylaldehyde and epichlorohydrin as bridges, modified diisobutylamine on the hybrid silica to obtain the adsorbents containing tertiary amine groups. It was found that the combined use of organic and inorganic precursors (one-pot) destroys the ordered mesoporous structure, but the organic units distributed more homogeneously which conducive to the progress of adsorption. For the samples prepared by one-pot, the adsorption capacity increased dramatically when the molar rate of APTES/SS is 0.3:1 (SS-0.5h-0.3N-DIBA, 221.37 mg g−1), and the adsorption behavior obeys the Langmuir model. The adsorption mechanism could be electrostatic attraction and chelation effect between ReO4− and nitrogenous group which demonstrated by FT-IR and XPS. In addition, the SS-0.5h-0.3N-DIBA could effectively separate Re(VII) from coexisting metal ions (Cu(II), Zn(II), Mn(II)) at pH

Amino-functionalized mesoporous materials based different mesoporous silica were prepared for the recovery of Mo(VI) from Re(VII)-containing solutions. The adsorption materials were characterized by SEM, HRTEM, TGA, XRD, N2 adsorption–desorption isotherms and Elemental analysis. The optimum type (SS5-1h-5.5@95) of mesoporous silica was determined by anchoring of mesoporous silica substrate with 3-aminopropyltriethoxysilane (APTES) via conventional methods and partitioned cooperative self-assembly process (PCSA process). Adsorption experimental data showed that the SS5-1h-5.5@95-APTES had a high affinity for Mo(VI) from Re(VII), and the maximum adsorption capacity was evaluated as 194.32 mg g− 1 in case of pH 1. Moreover, adsorption behavior, adsorption isotherm, adsorption kinetics and thermodynamics of Mo(VI) on the SS5-1h-5.5@95-APTES were studied, and adsorption mechanism was confirmed by FT-IR, Raman spectra and XPS analysis. The excellent affinity and selectivity make the SS5-1h-5.5@95-APTES become a potential material for recovery Mo(VI) from Re(VII) solution.

Sulfitobacter porphyrae ZFX1, isolated from surface seawater of the East China Sea during a Prorocentrum donghaiense bloom recession, exhibits high algicidal activity against P. donghaiense. To evaluate the algicidal effect of ZFX1, the algicidal mode and stability were investigated. The results showed that ZFX1 indirectly attacked algae by secreting algicidal compounds, and the algicidal activity of the ZFX1 supernatant was insensitive to different temperatures, light intensities and pH values (pH 3–12). To explore the algicidal mechanism of the ZFX1 supernatant, its effects on the morphological and ultrastructural alterations, photosynthetic capacity, reactive oxygen species (ROS) and antioxidative system of P. donghaiense were investigated. Scanning and transmission electron microscopy revealed that the ZFX1 supernatant destroyed the algal cell membrane structure and caused intracellular leakage. The decrease in the chlorophyll a content and the marked declines in both the photosynthetic efficiency (Fv/Fm) and the electron transport rate (rETR) indicated that the ZFX1 supernatant could damage the photosynthetic system of P. donghaiense. The excessive production of ROS in algal cells demonstrated the oxidative damage triggered by the ZFX1 supernatant. Although the antioxidant defense system of P. donghaiense was activated to scavenge excessive ROS, lipid oxidation occurred. The fatty acid composition profile indicated that the ZFX1 supernatant markedly increased the contents of two saturated fatty acids and a monounsaturated fatty acid and decreased the proportion of two polyunsaturated fatty acids, which resulted in lipids with a lower degree of unsaturation (DU). The decline in the DU decreased the lipid fluidity and rigidified the membrane system, and these effects destroyed the function of the membrane system and ultimately resulted in algal cell death. Therefore, ZFX1 probably plays a key role in mitigating P. donghaiense bloom by inducing lipid oxidation, decreasing the DU of lipids and ultimately destroying the membrane systems of algal cells.

An environmentally-friendly and fast analytical method for the stereoselective determination of etoxazole was developed and then applied to estimate stereoselective bioaccumulation and elimination in zebrafish using SFC-MS/MS. Optimal enantioseparation conditions were determined using a Chiralpak IG-3 column and CO2/MeOH mobile phase (80/20, v/v), at 3.0 mL/min within 1 min, 30°Me and 18 MPa. A modified QuEChERS method was developed for zebrafish sample pretreatment, and mean recoveries were 88.43–110.12% with relative standard deviations ranging from 0.32 to 5.34%. The enantioselectives of etoxazole enantiomers in zebrafish during uptake and depuration phases were evaluated. Significant enantioselective bioaccumulation was observed, with preferential accumulation of (−)-R-etoxazole compared to its antipode, during uptake at both low and high exposure concentrations. The toxic effects of etoxazole on zebrafish were further explored, and activities of antioxidant enzymes were determined in liver of zebrafish. Significant changes were observed in the SOD and GST activities and in the MDA levels, which indicated the occurrence of oxidative stress in liver of zebrafish. The toxic effects exhibited time- and dose-dependent properties. These results can facilitate the accurate risk evaluation of etoxazole and provide basic knowledge for further study of biotoxicity mechanisms.

Prorocentrum donghaiense blooms occur frequently in the Yangtze River estuary and the adjacent East China Sea. These blooms have damaged marine ecosystems and caused enormous economic losses over the past 2 decades. Thus, highly efficient, low-cost, ecofriendly approaches must be developed to control P. donghaiense blooms. In this study, a bacterial strain (strain Y42) was identified as Paracoccus sp. and was used to lyse P. donghaiense. The supernatant of the strain Y42 culture was able to lyse P. donghaiense, and the algicidal activity of this Y42 supernatant was stable with different temperatures and durations of light exposure and over a wide pH range. In addition to P. donghaiense, Y42 showed high algicidal activity against Alexandrium minutum, Scrippsiella trochoidea, and Skeletonema costatum, suggesting that it targets primarily Pyrrophyta. To clarify the algicidal effects of Y42, we assessed algal lysis and determined the chlorophyll a contents, photosynthetic activity, and malondialdehyde contents of P. donghaiense after exposure to the Y42 supernatant. Scanning electron microscopy and transmission electron microscopy analyses showed that the Y42 supernatant disrupted membrane integrity and caused algal cell breakage at the megacytic zone. Photosynthetic pigment loss and significant declines in both photosynthetic efficiency and the electron transport rate indicated that the Y42 supernatant damaged the photosynthetic system of P. donghaiense. Malondialdehyde overproduction indicated that the Y42 supernatant caused lipid peroxidation and oxidative damage to membrane systems in the algal cell, ultimately leading to death. The findings of this study reveal the potential of Y42 to remove algal cells from P. donghaiense blooms. IMPORTANCE P. donghaiense is one of the most common dinoflagellate species that form harmful algal blooms, which frequently cause serious ecological pollution and pose health hazards to humans and other animals. Screening for bacteria with high algicidal activity against P. donghaiense and studying their algicidal processes and characteristics will contribute to an understanding of their algicidal effects and provide a theoretical basis for preventing algal blooms and reducing their harm to the environment. This study reports the algicidal activity and characteristics of Paracoccus against P. donghaiense. The stability of the algicidal activity of Paracoccus in different environments (including different temperature, pH, and sunlight conditions) indicates its potential for use in the control of P. donghaiense blooms.

Three polymeric manganese(II) complexes [ Mn ( H 2 O ) 2 ( NTA ) ] ∞ 2 1 , [ Mn ( H 2 O ) 2 ( TNA ) ] ∞ 2 2 and [ Mn ( H 2 O ) 3 ( FNA ) ] ∞ 1 3 (HNTA = 2-nitroterephthalic acid; HTNA = 3-nitrophthalic acid; HFNA = 4-nitrophthalic acid), were synthesized and characterized. Compounds 1, 2 and 3 are assembled into 3D supramolecular network via O–H⋯O hydrogen bonds interactions. The Variable-temperature (2–300 K) magnetic susceptibility measurements of 1–3 show overall antiferromagnetic interactions between the high-spin Mn(II) (S = 5/2) ions. Results about i.r. spectra, thermal and elemental analyses are presented.

In recent years, Microcystis aeruginosa blooms have occurred throughout the world, causing huge economic losses and destroying aquatic ecosystems. It is necessary to develop effective and ecofriendly methods to control M. aeruginosa blooms. Here, we report a high algicidal activity of prodigiosin (PG) against M. aeruginosa as well as the algicidal mechanism. PG showed high algicidal activity against M. aeruginosa, with a 50% lethal dose (LD50) of 5.87 μg/mL in 72 h. A combination of methods, including propidium iodide and Annexin V-fluorescein staining assays and light and electron microscopy indicated the existence of two modes of cell death with features similar to those in eukaryotic programmed cell death: necrotic-like and apoptotic-like. Biochemical and physiological analyses showed that PG generates reactive oxygen species (ROS), which induce lipid peroxidation, damage the membrane system and destroy the function of the photosystem. A proteomics analysis revealed that many proteins were differentially expressed in response to PG stress and that most of these proteins were involved in important metabolic processes, which may trigger necrotic-like or apoptotic-like cell death. The present study sheds light on the multiple toxicity mechanisms of PG on M. aeruginosa and its potential for controlling the occurrence of M. aeruginosa blooms in lakes.

Lithium chloride (LiCl) has been reported to possess antiviral activity against several viruses. In the current study, we assessed the antiviral activity effect of LiCl on ALV-J infection in CEF cells by using real-time PCR, Western blot analysis, IFA and p27 ELISA analysis. Our results showed that both viral RNA copy number and protein level decreased significantly in a dose and time dependent manner. Time-course analysis revealed that the antiviral effect was more pronounced when CEFs were treated at the post infection stage rather than at early absorption or pre-absorption stages. Further experiments demonstrated that LiCl did not affect virus attachment or entry, but rather affected early virus replication. We also found that inhibition of viral replication after LiCl treatment was associated with reduced mRNA levels of pro-inflammatory cytokines. These results demonstrate that LiCl effectively blocked ALV-J replication in CEF cells and may be used as an antiviral agent against ALV-J.

Graphical abstract, Recent revolution of cryo-electron microscopy has opened a new door to solve high-resolution structures of macromolecule complexes without crystallization while how to efficiently obtain homogenous macromolecule complex sample is therefore becoming a bottleneck. Here we report SmartBac, an easy and versatile system for constructing large-sized transfer plasmids used to generate recombinant baculoviruses that express large multiprotein complexes in insect cells. The SmartBac system integrates the univector plasmid-fusion system, Gibson assembly method and polyprotein strategy to construct the final transfer plasmid. The fluorescent proteins are designed co-expressed with the target to monitor transfection and expression efficiencies. A scheme of screening an optimal tagged subunit for efficient purification is provided. Six large multiprotein complexes including the human exocyst complex and dynactin complex were successfully expressed and purified, suggesting a great potential of SmartBac system for its wide application in the future.

This paper proposes a new PCD (polycrystalline diamond) wheel with porous skeleton structure realized by removing the cobalt binder from PCD by EDM (electrodischarge machining), and investigates the grinding characteristics of the wheel. The pores are made successfully on PCD by adopting appropriate EDM conditions. The efficiency of making the pores is found to be higher, when the size of the diamond grains in the PCD material is small, and jumping motion to the copper electrode is not given during the EDM. A porous PCD grinding wheel made by this method using a rotating circular PCD (grain size of 10'm) disc of 20mm diameter has a good skeleton structure with sufficient projections on the wheel surface. A satisfactory grinding characteristics with a surface finish of Ra=0.02'm in grinding on a tungsten carbide work is achieved.

Phenol,as one of the main constituents of biomass tar, was used to gasify for hydrogen in this paper. It was studied that the influences of the reaction temperature, steam / biomass (S / B), load and the preparationof the catalyst on the hydrogen yield, gasification efficiency and hydrogen concentration. In the experiment, the catalyst loading material is porous ceramic foam. The results indicate that the S/B molar ratio of 2,the temperature of 1073 K and the load of 8% provide favorable operating conditions for steam reforming of phenol so as to get the highest hydrogen yield,gasification efficiency and hydrogen concentration. And it was easier to produce hydrogen when catalyst was calcinated for 1hour at 973K and the porosity is 20ppi.