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Redox tailoring enzymes play key roles in generating structural complexity and diversity in type II polyketides. In chartreusin biosynthesis, the early 13 C-labeling experiments and bioinformatic analysis suggest the unusual aglycone is originated from a tetracyclic anthracyclic polyketide. Here, we demonstrated that the carbon skeleton rearrangement from a linear anthracyclic polyketide to an angular pentacyclic biosynthetic intermediate requires two redox enzymes. The flavin-dependent monooxygenase ChaZ catalyses a Baeyer-Villiger oxidation on resomycin C to form a seven-membered lactone. Subsequently, a ketoreductase ChaE rearranges the carbon skeleton and affords the α-pyrone containing pentacyclic intermediate in an NADPH-dependent manner via tandem reactions including the reduction of the lactone carbonyl group, Aldol-type reaction, followed by a spontaneous γ-lactone ring formation, oxidation and aromatization. Our work reveals an unprecedented function of a ketoreductase that contributes to generate structural complexity of aromatic polyketide.

Atomically ordered intermetallic nanoparticles are promising for catalytic applications but are difficult to produce because the high-temperature annealing required for atom ordering inevitably accelerates metal sintering that leads to larger crystallites. We prepared platinum intermetallics with an average particle size of5 nanometers on porous sulfur-doped carbon supports, on which the strong interaction between platinum and sulfur suppresses metal sintering up to 1000°C. We synthesized intermetallic libraries of small nanoparticles consisting of 46 combinations of platinum with 16 other metal elements and used them to study the dependence of electrocatalytic oxygen-reduction reaction activity on alloy composition and platinum skin strain. The intermetallic libraries are highly mass efficient in proton-exchange-membrane fuel cells and could achieve high activities of 1.3 to 1.8 amperes per milligram of platinum at 0.9 volts.

Chemical study of the insect-derived bacterium, Streptomyces sp. NA4286, led to the discovery of four new polyketides, murayaquinones B-E (1–4), together with a known compound, murayaquinone (5). The structures of new compounds (1–4) were determined by extensive analysis of their NMR and HRESIMS data. The absolute configuration of (+)-1 and (−)-1 was assigned through comparison of experimental and calculated ECD spectra. Murayaquinone D (3) exhibited potent cytotoxic activities against six human cancer cell lines with IC50 values ranging from 1.03 to 9.99 μM.

Six novel aromatic polyketide dimers, bialternacins A-F (1-6), were isolated from a plant endophytic Alternaria sp. The structures of compounds 1-6 were elucidated on the basis of extensive spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism analysis. Compounds 1, 2, 5, and 6 were characterized as four pairs of racemic mixtures. Compound (+)-5 was demonstrated to show acetylcholinesterase inhibitory activity with an IC50 value of 15.5 μM. A putative biosynthetic pathway for these compounds was proposed.

The development of high-performance non-platinum group metal (non-PGM) catalysts for the oxygen reduction reaction (ORR) is still of significance in promoting the commercialization of proton exchange membrane fuel cells (PEMFCs). In this work, a “hierarchically porous carbon (HPC)-supporting” approach was developed to synthesize highly ORR active Fe–phenanthroline (Fe–phen) derived Fe–Nx–C catalysts. Compared to commercial carbon black supports, utilizing HPCs as carbon supports can not only prevent the formation of inactive iron nanoparticles during pyrolysis but also optimize the porous morphology of the catalysts, which eventually increases the amount of reactant-accessible and atomically dispersed Fe–Nx active sites. The prepared catalyst therefore exhibits a remarkable ORR activity in both half-cells (half-wave potential of 0.80 V in 0.5 M H2SO4) and H2–air PEMFCs (442 mA cm−2 at a working voltage of 0.6 V), making it among the best non-PGM catalysts for PEMFCs.

Genome mining of an indolocarbazole-type gene cluster from a marine-derived Nocardiopsis flavescens NA01583 strain led to the discovery of three new indolocarbazole alkaloids (1-3). Heterologous expression of the intact loo gene cluster in a surrogate host Streptomyces lividans K4-114 led to the successful production of 3. Notably, compound 1 showed potent cytotoxic activities toward eight cancer cell lines with IC50 values ranging from 41 to 283 nM.

The semihydrogenation of phenylacetylene to styrene represents an important process for optimizing the polystyrene production and also a model reaction for the evaluation of selective hydrogenation catalysts. Although the alloying strategy and surface engineering for noble metal (particularly for Pd) catalysts can effectively inhibit the overhydrogenation of styrene, the selectivity of phenylacetylene semihydrogenation to styrene is generally below 95% near the full conversion. Here, we demonstrate the electronic modulation of Pd-based bimetallic nanocluster catalysts based on the strong metal-support interactions for improving the catalytic selectivity for phenylacetylene semihydrogenation. A series of Pd-M (M = Fe, Co, Ni, Cu, Ga) bimetallic nanoclusters of ∼2 nm are immobilized on mesoporous sulfur-doped carbon (meso_S-C) supports, which exhibit a high selectivity of >97% for the semihydrogenation of phenylacetylene to styrene. The strong interaction between metal and the meso_S-C supports enables the modulation of electronic structure of the bimetallic nanoparticles and thus leads to the selectivity enhancement for the phenylacetylene semihydrogenation.

BackgroundQuantitativereal-time reverse transcriptase polymerase chain reaction is the common method to quantify relative gene expression. Normalizating using reliable genes is critical in correctly interpreting expression data from qRT-PCR.Euscaphis konishiiis a medicinal plant with a long history in China, which has various chemical compounds in fruit. However, there is no report describing the selection of reference genes in fruit development ofEuscaphis konishii.MethodsWe selected eight candidate reference genes based on RNA-seq database analysis, and ranked expression stability using statistical algorithms GeNorm, NormFinder, BestKeeper and ReFinder. Finally, The nine genes related to the anthocyanin synthesis pathway of Euscaphis konishii were used to verify the suitability of reference gene.ResultsThe results showed that the stability of EkUBC23, EkCYP38 and EkGAPDH2 was better, and the low expression reference genes (EkUBC23 and EkCYP38) were favourable for quantifying low expression target genes, while the high expression reference gene (EkGAPDH2) was beneficial for quantifying high expression genes. In this study, we present the suitable reference genes for fruit development of Euscaphis konishii based on transcriptome data, our study will contribute to further studies in molecular biology and gene function onEuscaphis konishiiand other closely related species.

Oxidative rearrangements play key roles in introducing structural complexity and biological activities of natural products biosynthesized by type II polyketide synthases (PKSs). Chartreusin (1) is a potent antitumor polyketide that contains a unique rearranged pentacyclic aromatic bilactone aglycone derived from a type II PKS. Herein, we report an unprecedented dioxygenase, ChaP, that catalyzes the final α-pyrone ring formation in 1 biosynthesis using flavin-activated oxygen as an oxidant. The X-ray crystal structures of ChaP and two homologues, docking studies, and site-directed mutagenesis provided insights into the molecular basis of the oxidative rearrangement that involves two successive C-C bond cleavage steps followed by lactonization. ChaP is the first example of a dioxygenase that requires a flavin-activated oxygen as a substrate despite lacking flavin binding sites, and represents a new class in the vicinal oxygen chelate enzyme superfamily.

A novel alkaloid, chartrenoline (1), featuring an unusual 6/6/5/5-tetracyclic nucleus, was isolated from a marine Streptomyces chartreusis NA02069. The structure of 1 including its absolute configurations was established by extensive analyses of its high resolution mass, NMR and single-crystal X-ray diffraction data. A plausible biosynthetic pathway for chartrenoline (1) is proposed.

The upregulation of proprotein convertase subtilisin/kexin type 9 (PCSK9) was reported to be involved in regulating the levels of inflammatory markers and apoptosis in macrophages. This study aims to investigate the function and regulation of PCSK9 in myocardial ischaemia. The results of our study showed dramatically increased expression of PCSK9 induced by hypoxia/reoxygenation (H/R) stress rather than by apoptosis in primary murine cardiomyocytes and HL-1 cells. Moreover, PCSK9 promoted H/R-induced pro-inflammatory cytokine release from macrophages, while silencing of PCSK9 inhibited the expression of the pro-inflammatory cytokines TNF-α, IL-6 and IL-1β. Additionally, PCSK9 facilitated the release of pro-inflammatory cytokines from macrophages under H/R conditions, which decreased cardiomyocyte viability and promoted apoptosis of cardiomyocytes. For the underlying mechanisms, we identified PCSK9-induced NF-κB activation as being involved in the cardiomyocyte apoptosis, which was blocked by the NF-κB inhibitor BAY 11-7082. Collectively, this study provides new insights into the therapeutic possibility of regulating PCSK9 in cardiomyocytes for the treatment of ischaemic cardiomyopathy.

Replacement of the native promoter of theglobal regulator LaeA-like gene of Daldinia eschscholzii by a strong gpdA promoter led to the generation of two novel cyclopentenone metabolites, named dalestones A and B, whose structures were assigned by a combination of spectroscopic analysis, modified Mosher's reaction, and electronic circular dichroism (ECD). Dalestones A and B inhibit the gene expression of TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.

A proteomic method combining two-dimensional polyacrylamide gel electrophoresis and tandem mass spectrometry was used to compare the hemolymph expression profiles of a beta-cypermethrin-resistant Blattella germanica L. strain (R) and a susceptible strain (S) after 24 h of beta-cypermethrin induction. The results showed that there were 42 differentially expressed proteins after induction of the R strain: 4 proteins were upregulated and 38 proteins were downregulated. One hundred one hemolymph proteins were differentially expressed after induction of the S strain: 53 proteins were upregulated and 48 proteins were downregulated. The identified proteins were mainly classified into the following categories: energy metabolism proteins such as arginine kinase and triose phosphate isomerase, detoxification-related proteins such as glutathione S-transferases (GSTs), signal molecule-regulated proteins such as nitric oxide synthase (NOS), and other proteins such as kinetic-related proteins and gene expression-related proteins. Several proteins show significant differences in response to short-term stress and long-term adaptation, and differential expression of these proteins reflects an overall change in cellular structure and metabolism associated with resistance to pyrethroid insecticides. In summary, our research has improved the understanding of the molecular mechanisms of beta-cypermethrin resistance in German cockroaches, which will facilitate the development of rational methods to improve the management of this pest.

The genus Monascus includes several species of fungi valued across Asia for their culinary uses and diverse medicinal properties. In this study, we evaluated the applicability of random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) markers in characterizing the genetic diversity in 41 Monascus strains collected from various regions of Fujian Province, the leading producer of Monascus in China.; Results: Seven screened ISSR primers generated 56 polymorphic bands, of which 93.33% were polymorphic. The genetic similarity coefficients (GSC) of the strains ranged from 0.50 to 1.00. Comparative sequence analysis using seven screened RAPD primers amplified a total of 49 polymorphic bands, of which 81.67% were polymorphic; GSC values ranged from 0.62 to 1.00.; Conclusion: Correlation analysis revealed a significant positive correlation in genetic distances assessed using above two markers, which indicated they were suitable for Monascus species characterization. ISSR markers were more suitable for the classification and determination of Monascus species, while RAPD markers appear to be preferable for analyzing the differences among strains within the same species. Our study revealed that Monascus possesses rich genetic diversity, and that the genetic relationships among the selected strains were, to a very limited extent, correlated to their geographical variation. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

Comparative studies for TiO2-passivated Al0.25Ga0.75N/GaN heterostructure FETs (HFETs) and TiO2-dielectric MOS-HFETs using nonvacuum ultrasonic spray pyrolysis deposition technique are made. Optimum device performances are obtained by tuning the layer thickness of TiO2 to 20 nm. High relative permittivity ( $k$ ) of 53.6 and thin effective oxide thickness of 1.45 nm are also obtained. Pulse-IV, Hooge coefficient ( $\alpha _{H}$ ), Transmission Electron Microscopy, and atomic force microscope have been performed to characterize the interface, atomic composition, and surface flatness of the TiO2 oxide. Superior improvements for the present TiO2-dielectric MOS-HFET/TiO2-passivated HFETs are obtained, including 47.6%/23.8% in two-terminal gate–drain breakdown voltage (BV $_{\rm GD})$ , 111%/22.2% in two-terminal gate-drain turn-ON voltage ( $V_{\mathrm{{\scriptscriptstyle ON}}})$ , 47.9%/39.4% in ON-state breakdown (BV $_{\rm DS})$ , 12.2%/10.2% in drain–source current density ( $I_{\rm DS})$ at $V_{\rm GS} = 0$ V ( $I_{\rm DSS0})$ , 27.2%/11.7% in maximum $I_{\rm DS}$ ( $I_{\rm DS, max})$ , 3/1-order enhancement in on/off current ratio ( $I_{\mathrm{{\scriptscriptstyle ON}}} / I_{\mathrm{{\scriptscriptstyle OFF}}})$ , 58.8%/17.6% in gate-voltage swing linearity, 25.1%/13.2% in unity-gain cutoff frequency ( $f_{T})$ , 40.6%/24.7% in maximum oscillation frequency ( $f_{\max })$ , and 33.8%/15.6% in power-added efficiency with respect to a Schottky-gated HFET fabricated on the identical epitaxial structure. The present MOS-HFET has also shown stable electrical performances when the ambient temperature is varied from 300 to 450 K.

Two new alkaloids, strepchazolins A (1) and B (2), together with a previously reported compound, streptazolin (3), were isolated from a marine actinomycete, Streptomyces chartreusis NA02069, collected in the Coast of Hainan Island, China. The structures of new compounds were determined by extensive NMR, mass spectroscopic and X-ray crystallographic analysis, as well as modified Mosher’s method. Compound 1 showed weak anti-Bacillus subtilis activity with the MIC value of 64.0 μM, and weak inhibitory activity against acetylcholinesterase (AChE) in vitro with IC50 value of 50.6 μM, while its diastereoisomer, Compound 2, is almost inactive.

Calcium plays a significant role in intracellular signaling. Calcineurin B-like proteins (CBLs) and their target proteins, CBL-interacting protein kinases (CIPKs) have emerged a calcium network responsing to stresses in plants. In this study, we cloned a CIPK gene,SpCIPK8, from the halophyte plantSesuvium portulacastrumandL. Bioinformation analysis showed that the cDNA ofSpCIPK8was 1344 bp and encoded 447 amino acids with a molecular weight of 50.72 KD and an isoelectric point of 7.19. One transmembrane domain exists in this hydrophilic protein. Phylogenetic analysis showed that SpCIPK8 was similar with AtCIPK8 inArabidopsis.The expression level ofSpCIPK8in stems was three times higher than that in roots and the level in leaves was two times higher than that in roots.

A full-length sequence coding for a betaine aldehyde dehydrogenase gene from S. portulacastrum was cloned into expression vector pGEX-4T-1, and named pGEX-4T-SpBADH. The GST-SpBADH fusion protein was expressed and the expression conditions were optimized. Through the research on optimization of expression the concentration of IPTG, concentration of bacterium, induction time and temperature and so on, the results showed, the expression of GST-SpBADH increased accompany with the induction time. The expression level of GST-SpBADH fusion protein reached the highest for 5 h cultured and for OD600 is about 0.6 at 37°C, 0.2 mmol/L IPTG can effectively induce the expression of GST-SpBADH in Escherichia coli expression system.

High-k TiO 2 -dielectric Al 0.25 Ga 0.75 N/GaN metal-oxide-semiconductor high-electron mobility transistors (MOS-HEMTs) grown on Si substrates by using nonvacuum ultrasonic spray pyrolysis deposition technique are reported for the first time. The effective oxide thickness is 1.45 nm with layer thickness/dielectric constant of 20 nm/53.6. Pulse I-V and low-frequency noise spectra (1/f) are conducted to characterize the interface property. The gate leakage current I GD is decreased by three orders at V GD = -50 V as compared with a reference Schottky-gate device. Superior device characteristics are achieved for the present MOS-HEMT (Schottky-gate HEMT) for the gate dimensions of 1 μm × 100 μm including drain-source current density I DS at V GS = 0 V (I DSS0 ) of 384 (342) mA/mm, maximum I DS (I DS , max ) of 650 (511) mA/mm, maximum extrinsic transconductance (g m , max ) of 107 (110) mS/mm, two-terminal gate-drain breakdown voltage (BVGD) of -155 (-105) V, turn-ON voltage (VON) of 3.8 (1.8) V, ON-state breakdown (BVDS) of 139 (94) V, gate-voltage swing of 2.7 (1.7) V, and ON/OFF current ratio (I ON /I OFF ) of 4.5 x 10 5 (3.5 x 10 2 ).

Implementation of green construction is a concrete manifestation of the concept of sustainable development in the construction phase. The key measures for green construction technology are energy saving, material saving, water saving and land saving during construction,as well as protecting environment and guaranteeing professional health. The comprehensive technologies for green construction in staff housing project of Xi'an Railway Bureau are introduced, as well as management measures, the measure of protecting the environment and resource conservation measures are described in detail. These measures may have some reference on promotion of green construction.

Using computational fluid dynamics (CFD) software Fluent, numerical simulation for unsteady flow around the vertical axis wind turbine (VAWT) was performed, which was based on the UDF controlled sliding meshes method. And SST k-ω turbulent model and SIMPLE algorithm were used to solve the unsteady incompressible N-S equation. Velocity magnitude profile, pressure, the blade force and the torque had been obtained by doing this. The result shows this method can effectively simulate the unsteady flow field performance of the variable-pitch vertical axis wind turbine, and it provides a new method for variable-pitch vertical axis wind turbine’s simulations.

The genus Monascus includes several species of fungi valued across Asia for their culinary uses and diverse medicinal properties. In this study, we evaluated the applicability of random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) markers in characterizing the genetic diversity in 41 Monascus strains collected from various regions of Fujian Province, the leading producer of Monascus in China.Seven screened ISSR primers generated 56 polymorphic bands, of which 93.33% were polymorphic. The genetic similarity coefficients (GSC) of the strains ranged from 0.50 to 1.00. Comparative sequence analysis using seven screened RAPD primers amplified a total of 49 polymorphic bands, of which 81.67% were polymorphic; GSC values ranged from 0.62 to 1.00.Correlation analysis revealed a significant positive correlation in genetic distances assessed using above two markers, which indicated they were suitable for Monascus species characterization. ISSR markers were more suitable for the classification and determination of Monascus species, while RAPD markers appear to be preferable for analyzing the differences among strains within the same species. Our study revealed that Monascus possesses rich genetic diversity, and that the genetic relationships among the selected strains were, to a very limited extent, correlated to their geographical variation. © 2016 Society of Chemical Industry.

A synchronous optical code-division multiple access system with balanced encoder instead of on-off-keying (OOK) encoder is proposed. In the system, the multi-user interference is maintained constant during a frame, and the receiver estimates the interference frame by frame instead of bit by bit. The data rate of the proposed system is no longer severely limited by the electronic processing time in estimating the interference, and the structure of the proposed receiver is simpler than those in OOK systems. In the receiver, both linear and non-linear threshold estimators are introduced. Numerical results show that the proposed system has smaller bit error rate than OOK systems, especially when the number of training bits is increased.

To determine the family member's depression status and its influencing factors in the patient with mental disorder caused by cerebral trauma.The self-designed information questionnaire and self-rating depression scale (SDS) were used to investigate 245 family members' depression conditions. On the basis of SDS score index, all cases were divided into depression group and non-depression group. The data were analyzed by the univariate analysis and multiple factors regression analysis.In the 245 family members, 117 family members had different degrees of depressive symptoms including 68 with mild depression, 42 with moderate depression, and 7 with severe depression. In the multiple factors regression analysis, genetic relationship, personality characteristics and payment method were the main influencing factors of the depression status.Much attention should be paid to the family member's depression condition of the patient with mental disorder caused by cerebral trauma through specific psychological intervention.

Study on the application of WAIS-RC short forms and adult intelligence disability scale in mental impairment assessment.Mental impairment assessment cases between July 2009 and March 2011 in judicial appraisal institute of Taizhou University were collected. Assessment results obtained with the WAIS-RC short forms and adult intelligence disability scale were compared with the experts assessing conclusions and analyzed using SPSS 11.5 software.Assessment results with the two scales did not fully comply with the expert's conclusions, with reliability coefficient were 0.785 and 0.940 respectively, correlation coefficient were 0.850 and 0.922 respectively.The intelligence assessment was influenced by many factors. When the appraised individuals had nerve dysfunction and mild intelligence disability or mental disorders, the two scales should be used together. When the appraised individuals had moderate intelligence disability or mental disorders, adult intelligence disability scale had advantage.

In the title compound, C16H14N4O, there are intermolecular N—H...N hydrogen bonds which may be effective in stabilizing the crystal. The title compound is an important medicament and is used in the synthesis of antitumour drugs.