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In this work, granular cold-water soluble waxy corn starch (N-GCWS) and granular cold-water soluble porous waxy corn starch (P-GCWS) were prepared by waxy corn starch (WS) treated with alcohol-alkali. Starch morphologies, crystal structures, turbidity, cold water viscosity, freeze-thaw stability and oil absorption capacity of N-GCWS and P-GCWS starches were compared. The results showed porous waxy corn starch (PS) was easier to prepare P-GCWS starch than WS to prepare N-GCWS. SEM showed that PS and WS became dent-twisted and tended to flatten with the increase of CWS. After alcohol-alkali treatment, the X-ray diffraction pattern of PS and WS changed from A type to amorphous and pores were remained on the surface of P-GCWS starches granular. Turbidity, freeze-thaw stability, viscosity, oil absorption capacity of N-GCWS and P-GCWS starches was shown higher than that of WS and PS. The oil absorption capacity of P-GCWS was higher than that of N-GCWS. • Granular cold-water soluble porous starch was prepared from porous waxy corn starch. • PS was easier to prepare P-GCWS than WS prepared N-GCWS. • The surface area of P-GCWS was higher than that of N-GCWS. • The oil absorption capacity of P-GCWS was higher than that of N-GCWS. [ABSTRACT FROM AUTHOR]

Summary: Peroxisomal proliferation is highly stimulated during the biosynthesis of mycotoxins and plant infection by Fusarium graminearum. Currently, the functions of the peroxisome in these cellular processes are poorly understood. In this study, we applied genetic, cell biological and biochemical analyses to investigate the functions of the peroxisomes. We constructed targeted deletion of docking machinery components, including FgPex13, FgPex14 and the filamentous fungal specific peroxin FgPex33. Our results indicated that peroxisome dysfunction resulted in a shortage of acetyl‐CoA, the precursor of trichothecene biosynthesis, and subsequently decreased deoxynivalenol (DON) production. Deletion mutants of ΔFgPex13, ΔFgPex14 or ΔFgPex33 showed an increased accumulation of endogenous reactive oxygen species (ROS) and reduced phosphorylation of MAP (Mitogen‐Activated Protein) kinase FgMgv1. In addition, mutants of the docking peroxin exhibited increased sensitivity toward host oxidative bursts and cell wall integrity stress agents and reduced virulence on host plants. More importantly, we found for the first time that FgPex14 is required for pexophagy in F. graminearum. Overall, our study suggests that peroxisomes play critical roles in DON biosynthesis and virulence in F. graminearum. [ABSTRACT FROM AUTHOR]

A comparative experiment about the production of starch nanocrystals (SNCs) with/without glucoamylase enzymatic pretreatment by sulfate acid hydrolysis from waxy potato starch (WPS) was employed in the present study. The research focused on the enhancement of the preparation efficiency while improving the dispersion of SNCs at the same time. The enzymatic pretreatment resulted in the decrease of acid hydrolysis duration. The minimum size and best dispersibility of nanocrystals was obtained after 5 days of hydrolysis. X-ray diffraction confirmed the increase of crystallinity (from 33% to 50.8%) and the polymorphic transitions (B–A) for nanocrystals harvested at day 5. The structure of nanocrystals was characterized by FT-IR, which suggested the presence of sulfate ester on the surface of SNCs. Zeta potential and size distribution revealed the prominent stability and dispersibility of nanocrystals at pH 7.0. SEM and TEM revealed that SNCs had square shapes with particle sizes ranging from 50 to 100 nm. [ABSTRACT FROM AUTHOR]

Abstract: Waxy maize starch was treated by pullulanase debranching and retrogradation at room temperature to produce resistant starch (RS). Physicochemical properties, crystalline structure and in-vitro digestibility of starch samples with different RS content were investigated. Compared with native starch, apparent amylose content of RS products increased. Based on Gel Permeation Chromatography (GPC) the Molecular Weight Distribution (MWD) of resistant starches significantly changed. Scanning Electron Microscopy (SEM) showed that upon pullulanase debranching and retrogradation treatment the granular structure of native starch was destroyed and all RS samples exhibited irregular shaped fragments. Crystal structure of samples changed from A–type to a mixture of B and V–type. The crystallinity of resistant starch also improved as compared with native starch. Moreover, samples with higher resistant starch showed higher relative crystallinity. Differential Scanning Calorimetry (DSC) determination showed that To、Tp、Tc and ΔH all increased which was in agreement with RS content. The resistance of waxy maize starch with Pullulanase treatment to α-amylase digestibility also increased, while the in-vitro digestibility of products decreased. [Copyright &y& Elsevier]

During the translation cycle, a cognate deacylated tRNA can only move together with the codon into the E site. We here present the first structure of a cognate tRNA bound to the ribosomal E site resulting from translocation by EF-G, in which an entire L1 stalk (L1 protein and L1 rRNA) interacts with E-site tRNA (E-tRNA), representing an authentic ribosome elongation complex. Our results revealed that the Watson-Crick base pairing is formed at the first and second codon-anticodon positions in the E site in the ribosome elongation complex, whereas the codon-anticodon interaction in the third position is indirect. Analysis of the observed conformations of mRNA and E-tRNA suggests that the ribosome intrinsically has the potential to form codon-anticodon interaction in the E site, independently of the mRNA configuration. We also present a detailed description of the biologically relevant position of the entire L1 stalk and its interacting cognate E-tRNA, which provides a better understanding of the structural basis for translation elongation. Furthermore, to gain insight into translocation, we report the positioning of protein L6 contacting EF-G, as well as the conformational change of the C-terminal tail of protein S13 in the decoding center. [ABSTRACT FROM AUTHOR]

A new macrocyclic dinuclear Zn(II) complex, [Zn2(OAc)L] · ClO4 (H2L was obtained by condensation between 3,3′-(ethane-1,2-diylbis(benzylazanediyl))bis(methylene)bis(2-hydroxy-5-methylbenzaldehyde) and aniline (1 : 2 molar ratio)), was synthesized and characterized by spectroscopy, elemental analysis, and single-crystal X-ray diffraction. The interactions of the complex with DNA have been measured by UV spectroscopy and viscosity experiment. The interaction of the complex with calf thymus DNA has a binding constant of 1.18 × 104 mol−1 L. Phosphate hydrolysis of the complex was investigated using bis(4-nitrophenyl)phosphate as the substrate. The observed first-order rate constant is 4.23 × 10−5  s−1. [ABSTRACT FROM AUTHOR]

The optically pure 3-hydroxy-3′,4′-methylenedioxy flavone-6-carboxylic acid was obtained through the chalcone route. The structure of 3-hydroxy-3′,4′-methylenedioxy flavone-6-carboxylic acid was first elucidated by single crystal X-ray analysis: triclinic, space group, triclinic ( P-1) with a = 8.1379(13) Å, b = 8.9831(14) Å, c = 13.198(2) Å, α = 88.413(2)°, β = 74.908(2)°, γ = 72.987(2)°. V = 889.5(2) Å3, Z = 2. The structure was solved by direct methods and refined to a final R = 0.0413 for 1630 reflections with I > 2 σ( I). The crystal structure is stabilized by O–H···O and C–H···O hydrogen bondings and π–π stacking interactions. The titled compound, 3-hydroxy-3′,4′-methylenedioxy flavone-6-carboxylic acid dimethylformamide solvate, was linked to one-dimensional molecular ribbons via intermolecular O–H···O and C–H···O hydrogen bondings.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: A novel polymeric complex NaCo(o-pba)3(H2O)3 (o-Hpba=2-(1-oxo-1H-2,3-dihydroisoindol-2-yl)benzonic acid) based on racemic N-arylphthalimidine ligand has been prepared and characterized by elemental analysis, spectroscopic and X-ray crystallography methods. In the compound, each Co(II) cation is coordinated by six O atoms from three carboxyl groups of o-pba− and three water molecules in fac-MA3B3 model forming a chiral tripodal Co(o-pba)3(H2O)3 − anion-complex, enantiomeric pairs of which are alternately arranged in head-to-head and tail-to-tail orientations giving rise to a meso-one-dimensional chain-like structure. The compound exhibits high stability and unusual triple-peak luminescence in DMSO solution at room temperature. [Copyright &y& Elsevier]

Whipping capabilities are the most important indices of dairy aerated emulsions for their use in cakes, desserts and toppings. However, poor whipping capabilities may occur because of included soft fats. Monoglycerides, namely glyceryl monostearate (GMS), glycerol monooleate (GMO) and glycerin monolaurate (GMLa), are the suggested improvers in controlling whipping process through changing partial coalescence behaviours of fat globules. Effects of the three monoglycerides on two crucial whipping factors, that is, fat crystallisation and interfacial properties, were analysed in the present study. It is found that low levels of monoglycerides (<0.25%) showed little effects on the development of partial coalescence, while positive performance was observed in those formulated with increased concentrations ranging from 0.50 to 0.75%. In comparison with GMO, monoglycerides with saturated species significantly improved density and ordering of fat crystal networks and reduced interfacial protein concentrations, contributing to the development of partial coalescence and bubble structures during whipping. Rheology analyses further strongly supported that GMS and GMLa strengthened fat crystal network structure, thereby improving shaping property and heat resistance of foam. The results provided a theoretical basis for improving whipping capabilities of aerated emulsions. [ABSTRACT FROM AUTHOR]

The influence of excessive lithium on the crystal structure, morphology, and electrochemical properties of Fe-deficient Li x FePO 4 ( x = 1.00, 1.02, 1.04, 1.05) cathode material was investigated using co-precipitation and the carbon thermal method. The X-ray diffraction pattern and Rietveld refinement results show that excessive Li + combines with the phosphate group to form Li 3 PO 4 rather than occupying the Fe site to form antisite pairs. Benefitting from the intrinsic ion conductivity of lithium phosphate, the lithium diffusion coefficient of Li x FePO 4 increases. However, the charge transfer impedance (Rct) also increases with increasing Li content due to the presence of Li 3 PO 4 , a nonconductive phase that can block the electric transfer channel. The biphasic Li x FePO 4 ( x = 1.02) compound shows the best performance. This work suggests an effective and easy way to improve the electrochemical performance by adding excessive Li, which leads to the formation of Li 3 PO 4 . [ABSTRACT FROM AUTHOR]

A new dinuclear europium cluster (Eu-cluster) is synthesized and the exact structure is determined by single-crystal X-ray diffraction. The formula of the Eu-cluster is determined to be [Eu 2 (4-Msal) 6 (phen) 2 (H 2 O) 2 ] (4-Msal = 4-methylsalicylic acid, phen = phenanthroline), it crystallizes in the triclinic space group P -1, with a = 9.1193(8) Å, b = 13.0855(10) Å, c = 14.0981(9) Å, α = 103.159(6)°, β = 94.192(6)°, γ = 100.632(7)°, V = 1598.3(2) Å 3 and Z = 1. Further investigation reveals that the Eu-cluster is a highly sensitive and selective methylmercury (CH 3 Hg + ) sensor. To the best of our knowledge, this is the first CH 3 Hg + sensor based on lanthanide clusters/complexes. The responsive behavior shows the sensing has excellent linearity in 1.4–3.8 μg L −1 μM. The LOD for sensing CH 3 Hg + is 0.8 μg L −1 , which meets the standard of Chinese environmental quality standard for agricultural and industrial water. Interestingly, study also reveals the sensor is applicable in real water sensing. [ABSTRACT FROM AUTHOR]

We synthesized LiNi 0.5 Mn 1.5 O 4 with the Fd-3m space group by using oxalate co-precipitation. The structure and morphology, electrochemical properties of the obtained LiNi 0.5 Mn 1.5 O 4 was investigated by XRD, SEM, galvanostatic charge/discharge testing and electrochemical impedance spectroscopy, respectively. Li/Ni antisite defects appeared in the disordered LiNi 0.5 Mn 1.5 O 4 . Using Rietveld refinement, we found that the second phase generated was Ni 6 MnO 8 rather than Li x Ni 1− x O. During the phase transformation, if sufficient Ni 6 MnO 8 was produced, the spinel structure could not sustain more Li in the original crystal lattice, which generated an unstable structure in which excess Li existed in Li 2 MnO 3 . Due to the high capacity of Li 2 MnO 3 , the capacity of spinel LiNi 0.5 Mn 1.5 O 4 with Li 2 MnO 3 is expected to further improve. [ABSTRACT FROM AUTHOR]

GRP78, a member of the ER stress protein family, can relocate to the surface of cancer cells, playing key roles in promoting cell proliferation and metastasis. GRP78 consists of two major functional domains: the ATPase and protein/peptide-binding domains. The protein/peptide-binding domain of cell-surface GRP78 has served as a novel functional receptor for delivering cytotoxic agents (e.g., a apoptosis-inducing peptide or taxol) across the cell membrane. Here, we report our study on the ATPase domain of GRP78 (GRP78ATPase), whose potential as a transmembrane delivery system of cytotoxic agents (e.g., ATP-based nucleotide triphosphate analogs) remains unexploited. As the binding of ligands (ATP analogs) to a receptor (GRP78ATPase) is a pre-requisite for internalization, we determined the binding affinities and modes of GRP78ATPase for ADP, ATP and several ATP analogs using surface plasmon resonance and x-ray crystallography. The tested ATP analogs contain one of the following modifications: the nitrogen at the adenine ring 7-position to a carbon atom (7-deazaATP), the oxygen at the β-γ bridge position to a carbon atom (AMPPCP), or the removal of the 2’-OH group (2’-deoxyATP). We found that 7-deazaATP displays an affinity and a binding mode that resemble those of ATP regardless of magnesium ion (Mg++) concentration, suggesting that GRP78 is tolerant to modifications at the 7-position. By comparison, AMPPCP’s binding affinity was lower than ATP and Mg++-dependent, as the removal of Mg++ nearly abolished binding to GRP78ATPase. The AMPPCP-Mg++ structure showed evidence for the critical role of Mg++ in AMPPCP binding affinity, suggesting that while GRP78 is sensitive to modifications at the β-γ bridge position, these can be tolerated in the presence of Mg++. Furthermore, 2’-deoxyATP’s binding affinity was significantly lower than those for all other nucleotides tested, even in the presence of Mg++. The 2’-deoxyATP structure showed the conformation of the bound nucleotide flipped out of the active site, explaining the low affinity binding to GRP78 and suggesting that the 2’-OH group is essential for the high affinity binding to GRP78. Together, our results demonstrate that GRP78ATPase possesses nucleotide specificity more relaxed than previously anticipated and can tolerate certain modifications to the nucleobase 7-position and, to a lesser extent, the β-γ bridging atom, thereby providing a possible atomic mechanism underlying the transmembrane transport of the ATP analogs. [ABSTRACT FROM AUTHOR]

Highlights: [•] This paper described the preparation and full characterization of a new phthalimidin derivative. [•] The compound exhibits blue–green emission with peaks at 354.5 and 486.5nm. [•] Second harmonic generation (SHG) property was investigated at the first time for this kind of compound. [•] The compound has moderate antibacterial and antifungi activities. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two pairs of rac- and meso-diastereomers were successfully separated. [•] Photolysis of (CMe2)(C9H7)(η 5-C9H6)Re(CO)3 (1) yielded the novel product (CMe2)[(η 5-C9H6)(η 2-C9H7)]Re(CO)2 (3). [•] Molecular structures of all compounds were determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-situ biochemical modification with xanthan gum addition was carried out. • Tieguanyin oolong tea residue hydrolysate was used as the fermentation substrate. • The bacterial cellulose yield increased by 260.8% with 0.6% xanthan gum addition. • Bacterial cellulose and xanthan gum were combined by the modification. • The performance of bacterial cellulose was promoted due to the modified structure. The effect of in-situ biochemical modification on the synthesis, structure, and function of xanthan gum based bacterial cellulose generated from Tieguanyin oolong tea residue hydrolysate was evaluated for the first time. This modification could overcome the inhibitory effect of the hydrolysate and the bacterial cellulose yield with 0.6% xanthan gum addition increased by 260.8% compared with that without xanthan gum addition. Bacterial cellulose and xanthan gum were combined by the in-situ modification and the alteration of fermentation medium rheological properties by xanthan gum addition might be beneficial for their combination. The average diameter of the bacterial cellulose microfibrils was increased by the modification, and it had a great influence on the crystalline structure of the bacterial cellulose. Additionally, both the water absorption and texture properties of the bacterial cellulose was strengthened by the modification. Overall, this modification showed great potential for efficient and effective xanthan gum based bacterial cellulose production. [ABSTRACT FROM AUTHOR]

Vanadium oxide (VOx) is a promising candidate as a material for smart windows, and 0.7 wt% Nb-doped SrTiO3 (NSTO) is frequently used in electrodes for electro-optic devices. Here, we demonstrate that a rectifying VOx/Nb: SrTiO3 heterojunction has a photovoltaic response. It can be used in thermochromic photovoltaic modulating devices. The crystalline structure and electrical characteristics of VOx thin film deposited on NSTO were investigated. It was found that an asymmetric hysteresis current between increasing and decreasing voltages occurs at 80, 300 and 360 K. The photovoltaic effect was observed under irradiation by a pulsed laser. [ABSTRACT FROM AUTHOR]

A new Cu(II) complex with flavonoxylacetate ligand was synthesized and characterized. The structure of the complex was determined by X-ray single crystal diffraction technique. In the crystal structure, flavonoxylacetate coordinates Cu(II) ion in bidentate mode resulting in a chelating pentagonal coordination structure. Central Cu(II) has an elongated octahedral coordination showing a strong Jahn-Teller effect. The stability of the crystal structure was investigated by thermal gravimetric analyses. The loss of coordination water in crystals occurs above 150 °C. Fluorescence spectra are affected by pH value and coordination metal ion as well as the substitution pattern of the carboxymethoxy on the flavone skeleton. Furthermore, the fluorescence quenched in the Cu(II) complex recovered with increase of S2- ion concentration. [ABSTRACT FROM AUTHOR]

Hydroalkoxylation is a useful and efficient reaction which generates C–O bond and produces cyclic ethers, the common structural elements of natural products. The dedicative enzyme which can catalyze enantioselective hydroalkoxylation named PhnH was recently identified in the herqueinone biosynthetic gene from Penicillium herquei. It catalyzes addition of a phenol to the terminal olefin on substrate to produce a dihydrobenzofuran. Here, the crystal structure of PhnH is reported and the putative substrate-binding pocket is illustrated. Through docking experiment, possible substrate-binding poses are displayed and the catalytic mechanism is therefore proposed. Our findings form the basis for further studies of enantioselective hydroalkoxylation enzymes. • Crystal structure of PhnH was solved. • PhnH catalyzes intramolecular enatioselective hydroalkoxylation. • Substrate-binding mode and catalytic mechanism of PhnH are proposed. [ABSTRACT FROM AUTHOR]

• Synthesis of strobilurin derivatives containing oxime ether phenyl ring or dihydrobenzofuran moiety. • The strobilurin derivatives exhibited certain degree of fungicidal and insecticidal activities. • The potential mechanism of fungicidal activity of novel strobilurins was analyzed by molecular docking. Two sets of strobilurin derivatives containing oxime ether phenyl ring or dihydrobenzofuran moiety were designed, synthesized and evaluated for their fungicidal and insecticidal activities. The structures of the target compounds were determined by 1H NMR, 13C NMR and elemental analysis, and the crystal structure of compound 3a was further determined by X-ray diffraction analysis. Some of the title compounds exhibited certain degree of fungicidal and insecticidal activities at the concentration of 500 mg/L. The control effects of compounds 1, 4a and 8 against Erysipe graminis and 1, 3a, 4a and 8 against Puccinia sorghi were all above 90%, which were close to the level of trifloxystrobin. The lethal rates of compounds 5a and 6a against Mythimna separata reached 100%, similar to that of positive control chlorantraniliprole, and the lethal rates of compounds 1, 2 and 8 against Aphis fabae were 100%, 100% and 98.6%, respectively, numerical equivalent to that of imidacloprid. Furthermore, molecular docking showed the potential mechanism for fungicidal activities of these compounds, and DFT calculation indicated that the frontier molecular orbitals and van der Waals surface electrostatic potentials could be related to insecticidal activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Luminescence mechanism of self-activated phosphor Ca 0.75 Sr 0.2 Mg 1.05 Si 2 O 6 (CSMS) originating from oxygen vacancy defects has been deeply investigated by regulating synthesis temperature. The results demonstrate that the luminescence comes from three different oxygen defects in the crystal structure. For Ce3+ doped CSMS (ICSD#68180), two concentration quenching phenomena can be observed at x = 0.03 and 0.12 as the result of the formation of new substance CaMgSi 2 O 6 (ICSD#17043), which leads to the actual concentration of Ce3+in CSMS (ICSD#68180) is far less than the doping concentration since part of Ce3+ ions enter CaMgSi 2 O 6 (ICSD#17043). The emission spectra of CSMS: x Ce3+ shifts from 388 nm to 405 nm with increasing Ce3+ content, which mainly should be due to the 5d energy center of Ce3+ shifting down and the crystal field split. Graphical abstracts fx1 [ABSTRACT FROM AUTHOR]

A series of color-tunable NaBa1−zSrzB9O15:Ce3+,Mn2+ phosphors were synthesized by a high temperature solid state method. Luminescence property, energy transfer, thermal stability and cation substitution were investigated in detail. Due to energy transfer, NaBaB9O15:Ce3+,Mn2+ presents violet to green luminescence and manifest a broad excitation range from 200 to 350 nm. The energy transfer mechanism of Ce3+–Mn2+ is identified as a dipole–dipole interaction. NaBa1−zSrzB9O15:Ce3+,Mn2+ displays both Ce3+ violet and Mn2+ green and orange emissions under ultraviolet excitation. It is observed that Sr2+ partial substitution for Ba2+ could adjust the ratio of Mn2+ emission intensity in different cation sites, which results from preferred sites’ occupation with modification of the crystal structure. Furthermore, increase in temperature can enhance the energy transfer from Ce3+ to Mn2+, which enhances the Mn2+ emission intensity sharply. The highly thermal-sensitive property of NaBa1−zSrzB9O15:Ce3+,Mn2+ makes it feasible for its potential application in luminescent ratiometric thermometers with wide temperature range. [ABSTRACT FROM AUTHOR]

Abstract: Historically, paper is the medium to write information. Here, the concept of writing is expanded from the addition of mass (i.e., ink) onto a static polysaccharide medium (i.e., paper), to the addition of electrical energy to a dynamically reconfigurable polysaccharide medium. Specifically, a dual‐responsive interpenetrating polysaccharide network is used as a dynamic medium. Electrical writing is achieved using an electrode pen to locally perform the cathodic electrolysis reactions that generate high‐pH regions that neutralize the interpenetrating chitosan chains and induce their self‐assembly into crystalline regions. Surprisingly, the gradients in structure induced by cathodic writing are stable even after the pH gradient has dissipated. Molecular modeling indicates that this stability results from structure‐induced changes in chitosan's pKa. Various experimental approaches demonstrate that the changes in structure generated by cathodic writing alter the medium's mechanical, chemical, and biological properties. Importantly, the structure and information imparted into the film is reversible allowing the medium to be erased and new information to be written. Broadly, this work demonstrates the use of top‐down electrical inputs to induce bottom‐up structural changes in a biopolymer‐based medium and these structural changes fundamentally alter how this medium interacts chemically and biologically with its environment. [ABSTRACT FROM AUTHOR]

Graphical abstract Three series of Ln-CPs based on 1,3-adamantanediacetic acid are synthesized and the structure variation is analyzed. The luminescence of Eu- and Tb-CPs is studied. Highlights • Three series (3D, 2D and 1D) of Ln-CPs single crystals were obtained. • The structure variation was analyzed. • The luminescence of Ln-CPs was investigated. Abstract We report the synthesis of 3D Ln-CPs [Tb 2 (ADA) 3 ] n (1a , H 2 ADA = 1,3-adamantanediacetic Acid), 2D Ln-CPs [Ln 2 (ADA) 3 (dmp) 2 ] n ·2EtOH·H 2 O, (Ln3+ = Eu3+, 2a ; Gd3+, 2b ; Tb3+, 2c ; dmp = 4,7-dimethyl-1,10-phenanthroline), and 1D Ln-CPs [Ln(ADA)(HADA)(H 2 O)] n (Ln3+ = Eu3+, 3a ; Gd3+, 3b ; Tb3+, 3c), by introducing the ligand H 2 ADA. The Ln-CPs are characterized by single-crystal X-ray diffraction, PXRD, TGA, elemental analysis and FT-IR. Structure variation is analyzed and suggestions are given for obtaining different types of structures. Luminescence spectra, lifetimes and quantum yields (QYs) are investigated. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEN) is a mycotoxin which causes huge economic losses in the food and animal feed industries. The lactonase ZHD101 from Clonostachys rosea, which catalyzes the hydrolytic degradation of ZEN, is the only known ZEN-detoxifying enzyme. Here, a protein homologous to ZHD101, denoted CbZHD, from Cladophialophora batiana was expressed and characterized. Sequence alignment indicates that CbZHD possesses the same catalytic triad and ZEN-interacting residues as found in ZHD101. CbZHD exhibits optimal enzyme activity at 35°C and pH 8, and is sensitive to heat treatment. The crystal structure of apo CbZHD was determined to 1.75 Å resolution. The active-site compositions of CbZHD and ZHD101 were analyzed. [ABSTRACT FROM AUTHOR]

In this work, waxy maize starch nanocrystals were prepared by mixed acid of sulfuric acid and hydrochloric acid for the first time. Physicochemical properties, crystalline structure, and particle size of starch nanocrystals prepared by mixed acid (HSNC) were measured. The results showed that there was no difference in particle morphology, group structure, and surface elements of HSNC and starch nanocrystals prepared by sulfuric acid (SNC), which was a conventional preparation method. The yield of HSNC was lower than that of SNC. However, the preparation time of HSNC was greatly shortened to 1 h which is only 0.83 % of the time (5 d) to prepare SNC by the sulfuric acid, and HSNC showed higher relative crystallinity and smaller size than those of SNC. In addition, when the ratio of sulfuric acid and hydrochloric acid to provide H ion concentration was 1:1 to hydrolyze starch for >1 h, the crystal pattern of HSNC would be changed to V-typed, while the crystal pattern of SNC was still A-typed. Thus, this work provided efficient method for preparing starch nanocrystals is provided, which can replace sulfuric acid hydrolysis to prepare SNC. • Mixed acid were used to prepare starch nanocrystals (HSNC) in 1 h • Starch nanocrystals prepared by mixed acid shortened than conventional preparation • HSNC prepared by mixed acid had higher relative crystallinity and smaller size • The crystal pattern of HSNC prepared >1 h would change to V-typed [ABSTRACT FROM AUTHOR]

The article discusses the crystal structure of 4-acetamidophenyl nicotinate, whose chemical formulae is C14H12N2O3. Topics discussed, include its physical properties, chemical formula, chemical structure, and its atomic coordinates and displacement parameters.

Eukaryotic 1,4-β-endoglucanases (EC 3.2.1.4) have shown great potentials in many commercial applications because they effectively catalyze hydrolysis of cellulose, the main component of the plant cell wall. Here we expressed a glycoside hydrolase family (GH) 5 1,4-β-endoglucanase from Aspergillus niger (AnCel5A) in Pichia pastoris , which exhibits outstanding pH and heat stability. In order to further investigate the molecular mechanism of AnCel5A, apo-form and cellotetraose (CTT) complex enzyme crystal structures were solved to high resolution. AnCel5A folds into a typical (β/α) 8 -TIM barrel architecture, resembling other GH5 members. In the substrate binding cavity, CTT is found to bind to −4 – −1 subsites, and several polyethylene glycol molecules are found in positive subsites. In addition, several unique N -glycosylation motifs that may contribute to protein higher stability were observed from crystal structures. These results are of great importance for understanding the molecular mechanism of AnCel5A, and also provide guidance for further applications of the enzyme. [ABSTRACT FROM AUTHOR]

Ganoderma lucidum is a saprotrophic white-rot fungus which contains a rich set of cellulolytic enzymes. Here, we screened an array of potential 1,4-β-endoglucanases from G. lucidum based on the gene annotation library and found that one candidate gene, GlCel5A, exhibits CMC-hydrolyzing activity. The recombinant GlCel5A protein expressed in Pichia pastoris is able to hydrolyze CMC and β-glucan but not xylan and mannan. The enzyme exhibits optimal activity at 60 °C and pH 3–4, and retained 50% activity at 80 and 90 °C for at least 15 and 10 min. The crystal structure of GlCel5A and its complex with cellobiose, solved at 2.7 and 2.86 Å resolution, shows a classical (β/α) 8 TIM-barrel fold as seen in other members of glycoside hydrolase family 5. The complex structure contains a cellobiose molecule in the +1 and +2 subsites, and reveals the interactions with the positive sites of the enzyme. Collectively, the present work provides the first comprehensive characterization of an endoglucanase from G. lucidum that possesses properties for industrial applications, and strongly encourages further studying in the cellulolytic enzyme system of G. lucidum . [ABSTRACT FROM AUTHOR]

Solution assembly of heterocyclic disulfide ligand, 4-ppds {4-ppds = bis[4-(pyridin-4-yl)pyrimidinyl]disulfide}, with Cu(OAc)2 and ZnI2 resulted in two 1D (one-dimensional) coordination polymers 1 and 2, which were well characterized by infrared spectroscopy, elemental analysis, powder X-ray diffraction, single-crystal X-ray diffraction, diffuse-reflectance UV/Vis as well as photoluminescence spectroscopy. Single crystal X-ray crystallography discloses that 1 shows an achiral zigzag chain structure built up by alternate linking of paddlewheel Cu2(OAc)4 dicopper unit and 4-ppds ligand with opposite configurations, whereas 2 exhibits a helical chain structure constructed by alternate linkage of tetrahedral zinc atom and 4-ppds ligand with the same chirality ( P- or M-configuration). It is supposed that the flexible coordination environment around the tetrahedral ZnII ion might be beneficial to homochiral arrangement of 4-ppds ligand. [ABSTRACT FROM AUTHOR]

SelaginpulvilinsA–D (1–4), four new phenolswith an unprecedented 9,9-diphenyl-1-(phenylethynyl)-9H-fluorene skeleton, together with four known selaginellins(5–8) were isolated from Selaginella pulvinata. Their structures were elucidatedby spectroscopic analysis and chemical correlation. The structureof 1was confirmed by single-crystal X-ray diffraction.Compounds 1–8exhibited remarkableinhibitory activities (IC50values in the range of 0.11–5.13μM) against phosphodiesterase-4 (PDE4), a drug target for thetreatment of asthma and chronic obstructive pulmonary disease. [ABSTRACT FROM AUTHOR]

Two cobalt(II) complexes [Co(QCT)2]·Cl·1.5H2O (1) (QCT = quinoline-2-carboxaldehyde thiosemicarbazone) and [Co(QCMT)(CH3OH)Cl2] (2) (QCMT = quinoline-2-carboxaldehydeN4-methyl-thiosemicarbazone) have been synthesized and structurally characterized. Complex1crystallizes in a triclinic system with space groupP–1 and complex2crystallizes in a monoclinic system with space groupP2(1)/n. In both complexes the cobalt(II) center is six coordinated with distorted octahedral geometry. The interactions of two complexes with CT-DNA were investigated by electronic absorption spectra, circular dichroism (CD) spectra and fluorescence spectra. Results suggest that the complexes bind to DNAviagroove binding mode, and complex2has stronger binding ability than complex1. Thein vitrocytotoxicity has been tested against the human lung adenocarcinoma cell line A-549, cisplatin-resistant cell line A-549/CDDP, and human breast adenocarcinoma cell line MCF-7. Complex2is more cytotoxic than complex1, and both of them show higher cytotoxicity than the parent ligands alone. Compared with cisplatin, the two cobalt(II) complexes are more active against A-549/CDDP and MCF-7 cell lines at most experimental concentrations. Notably, although complex 2 is found to be less effective than cisplatin against the parent cell line A-549, it is much more effective than cisplatin against the resistant cell A-549/CDDP. [ABSTRACT FROM PUBLISHER]

A series of Na 1-z K z Ba 1-y Sr y B 9 O 15 :Eu2+ were synthesized by the high temperature solid state method. H 3 BO 3 excess makes it easier for Eu2+ to enter Na+ site, and the single-phase "blue + green" double emission band can be observed, which is proved by thermoluminescence and the change of crystal structure. Moreover, there exists an intense energy transfer from the blue-emitting center to the green-emitting center, which is proved by the decay curve. The occupation of Eu2+ can be tuned by the introduction of Sr2+ and K+ in NaBaB 9 O 15. Further, the highly thermal-sensitive property of NaBaB 9 O 15 : 1%Eu2+ makes it feasible for its potential application in luminescent ratiometric thermometers with wide temperature range. In addition, the disorder degree of matrix cations increases with the incorporation of K+, which improves the thermal stability. Image 1 • Eu2+ can enter into Na+ site with the excessive H 3 BO 3 and muti-band emission is achieved. • Sr2+/K+ can adjust the occupied radio of Eu2+ in Ba2+ and Na+ site. • K+ can improve the thermal stability of NBB:Eu2+ due to the disorder degree of matrix cations. • NBB:1%Eu2+ could be a versatile solid-state probe. [ABSTRACT FROM AUTHOR]