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Efficient Activity Enhancement of a Lipase from Sporisorium reilianum for the Synthesis of a Moxifloxacin Chiral Intermediate via Rational Design

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Engineering 2022年第12期19卷 207-216页

作者： Xue Cai Jiang-Wei Shen Yu qiang Jing Hua zhang-qi ma Zhi-qiang Liu Yu-Guo Zheng The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of TechnologyHangzhou 310014China Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and BioengineeringZhejiang University of TechnologyHangzhou 310014China

Lipase-catalyzed stereoselective resolution of cis-(±)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate(cis-(±)-1)is an attractive route for the synthesis of(S,S)-2,8-diazobicyclo[4.3.0]nonane,an important chiral intermediate of the fluoroquinolone antibiotic,*** our previous study,a lipase from Sporisorium reilianum(SRL)was identified to possess excellent thermostability and pH ***,the low enzymatic activity of the SRL is a challenge that must be addressed.A rational design was initially employed for SRL tailoring according to the engineered Candida antarctica lipase B(CALB),resulting in a beneficial variant called SRL-I194N/***,two key amino acid residues in loop 6,L145 and L154,which might modulate the lid conformation between open and closed,were identified.A tetra-site variant,SRL-I194N/V195L/L145V/L154G(V13),with a significantly enhanced activity of 87.8 U∙mg^(−1) was obtained;this value was 2195-fold higher than that of wild-type *** V13 was used to prepare optically pure(2S,3R)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate((2S,3R)-1),resolving 1 mol∙L^(−1) cis-(±)-1 with a conversion of 49.9%in 2 h and absolute stereoselectivity(E>200).Excellent stability with a half-life of 92.5 h was also observed at 50℃.Overall,the study findings reveal a lipase with high activity toward cis-(±)-1 at an industrial level and may offer a general strategy for enhancing the enzyme activity of other lipases and other classes of enzymes with a lid moiety.

关键词： Lipase Sporisorium reilianum Site-directed mutagenesis Molecular dynamics simulation Rational design Moxifloxacin

Open-vessel Synthesis of Poly-N-methoxyethylglycine

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Chemical Research in Chinese Universities 2024年第1期40卷 153-158页

作者： LIU Guojan ma Ke CHEN qi zhang Donghui LIU Runhui State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai200237P.R.China Key Laboratory for Ultrafine materials of Ministry of Education Frontiers Science Center for Materiobiology and Dynamic ChemistryShanghai Frontiers Science Center of Optogenetic Techniques for Cell MetabolismResearch Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237P.R.China School of Biotechnology East China University of Science and TechnologyShanghai200237P.R.China

Polypeptoids are widely used in biological applications owing to their diverse functions and proteolytic *** type of polypeptoids,poly-N-methoxyethylglycine(P-Nmeg),has been found to possess remarkable hydrophilicity and notable properties in terms of protein,cell,and bacterial ***,the currently known synthesis methods of P-Nmeg include solid-phase synthesis,which is time-consuming and difficult to scale up,and N-substituted N-carboxyanhydride(NNCA)ring-opening polymerization,whose monomers were difficult to *** this study,we used the chemical stable Nmeg N-phenoxycarbonyl(NPC)as the monomer,which was obtained without the use of highly toxic reactants,such as phosgene or phosphorus halide,to synthesize P-Nmeg under open-vessel *** adding BnNH_(2) as an initiator at 80℃,we can obtain controllable short chain length P-Nmeg with narrow dispersity.

关键词： Open-vessel Polypeptoid synthesis Poly-N-methoxyethylglycine Stable monomer Narrow dispersity

Electrical discharge and arc milling with automatic tracking of optimal flushing direction:A novel high-efficiency compound machining method

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Chinese Journal of Aeronautics 2024年第3期37卷 351-364页

作者： Xinlei WU Yonghong LIU Pengxin zhang Liang qi Dege LI Chi ma Renjie JI College of Mechanical and Electronic Engineering China University of Petroleum(East China)Qingdao 266580China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China

The arc milling method has the advantages of high machining efficiency and low cost and is independent of the strength and hardness of machined ***,frequent electrode back-offs and the risk of workpiece burning may occur if erosion products are not removed *** this study,it was found that the flushing method of the working medium had a significant impact on the machining performance of arc *** on this,a novel highefficiency compound machining method of electrical discharge and arc milling with automatic tracking of the optimal flushing direction was *** automatic tracking optimizer for external working medium injection was designed to determine the optimal external flushing direction according to the feed *** influence of flushing methods,working mediums,and machining parameters on the machining efficiency,tool electrode wear rate,machining error,and surface integrity of titanium alloys were *** results indicated that better machining performance and environmental friendliness were achieved using the compound flushing method of outer compressed air and inner deionized ***,the automatic tracking flushing method in the opposite direction of the feed direction showed superior results compared to other *** material removal rate with the opposite direction injection could be increased up to 1.62 times that of the same direction,and the relative electrode wear rate could be reduced by 14.76%.This novel method has broad application prospects for machining parts with difficult-to-cut materials in aerospace and military industries.

关键词： Arc milling Dielectric Difficult-to-cut materials Electric discharge machining Erosion material removal rate

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Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China mathematics 2024年第1期67卷 211-236页

作者： qi Lü Bowen ma School of mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy

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Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： Yong qi Shufen zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic *** can produce one or more temporary shapes through nanoscale deformation,memorizing current *** can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural *** porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and ***,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and *** primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface *** aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of ***,perspectives on future research directions and applications are also *** is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Two ABCI family transporters,OsABCI15 and OsABCI16,are involved in grain-filling in rice

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Journal of Genetics and Genomics 2024年第5期51卷 492-506页

作者： Bin ma Xiubiao Cao Xiaoyuan Li Zhong Bian qi-qi zhang Zijun Fang Jiyun Liu Qun Li qiaoquan Liu Lin zhang Zuhua He Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Zhongshan Biological Breeding Laboratory/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology Agricultural College of Yangzhou UniversityYangzhouJiangsu 225009China Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Jiangsu Key Laboratory of Crop Genetics and PhysiologyYangzhou UniversityYangzhouJiangsu 225009China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology&EcologyChinese Academy of SciencesShanghai 200032China Institute of Biotechnology Hangzhou Academy of Agricultural SciencesHangzhouZhejiang 310024China Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education Yangzhou UniversityYangzhouJiangsu 225009China

Seed development is critical for plant reproduction and crop yield,with panicle seed-setting rate,grain-filling,and grain weight being key seed characteristics for yield ***,few genes are known to regulate grain ***,we identify two adenosine triphosphate(ATP)-binding cassette(ABC)I-type transporter genes,OsABCI15 and OsABCI16,involved in rice *** genes are highly expressed in developing seeds,and their proteins are localized to the plasma membrane and ***,knockout of OsABCI15 and OsABCI16 results in a significant reduction in seed-setting rate,caused predominantly by the severe empty pericarp phenotype,which differs from the previously reported low seed-setting phenotype resulting from failed *** analysis indicates that OsABCI15 and OsABCI16 participate in ion homeostasis and likely export ions between filial tissues and maternal tissues during grain ***,overexpression of OsABCI15 and OsABCI16 enhances the seed-setting rate and grain yield in transgenic plants and decreases ion accumulation in brown ***,the OsABCI15/16 orthologues in maize exhibit a similar role in kernel development,as demonstrated by their disruption in transgenic ***,ourﬁndings reveal the important roles of two ABC transporters in cereal grain filling,highlighting their value in crop yield improvement.

关键词： ABC transporters Rice Grain filling Ion homeostasis Grain yield

Host plant traits play a crucial role in shaping the composition of epiphytic microbiota in the arid desert,Northwest China

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Journal of Arid Land 2024年第5期16卷 699-724页

作者： zhang Jun zhang Yuanming zhang qi State Key Laboratory of Desert and Oasis Ecology Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Biodiversity Conservation and Application in Arid Lands Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Xinjiang Field Scientific Observation Research Station of Tianshan Wild Fruit Forest Ecosystem Yili Botanical GardenXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China College of Life Sciences Shihezi UniversityShihezi 832003China

Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and ***,the impact of host characteristics on shaping phyllosphere microbial communities of plants with different life forms remains *** high-throughput sequencing technology,this study analyzed the diversity and community composition of phyllosphere epiphytic microorganisms(e.g.,bacteria and fungi)of various plant life forms in the hinterland of the Gurbantunggut Desert,Northwest *** annotation of prokaryotic taxa(FAPROTAX)and fungi function guild(FUNGuild)were employed to assess the ecological functions of microorganisms and to investigate the role of stochastic and deterministic processes in shaping phyllosphere microbial *** showed a diverse array of phyllosphere epiphytic microorganisms in the desert plants,with Proteobacteria,Cyanobacteria,and Actinobacteriota dominating bacterial community,while Ascomycota and Basidiomycota were prevalent in fungal *** across different plant life forms highlighted distinct microbial communities,indicating strong filtering effects by plant *** prediction identified intracellular parasites(accounting for 27.44%of bacterial community abundance),chemoheterotrophy(10.12%),and phototrophy(17.41%)as the main functions of epiphytic bacteria on leaves of different life form *** prediction indicated that phyllosphere epiphytic fungi primarily served as Saprotrophs(81.77%),Pathotrophs(17.41%),and Symbiotrophs(0.82%).Co-occurrence network analysis demonstrated a predominance of positive correlations among different microbial ***-Crick dissimilarity index analysis revealed that deterministic processes predominantly influenced phyllosphere bacterial and fungal community *** partitioning analysis and random forest modeling suggested that pla

关键词： phyllosphere epiphytic bacteria phyllosphere epiphytic fungi community structure community diversity functional diversity plant life form plant functional traits

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Dammarane-type triterpenoids from Gynostemma longipes and their protective activities on hypoxia-induced injury in PC12 cells

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Chinese Journal of Natural Medicines 2024年第5期22卷 466-480页

作者： LIANG Haizhen CHEN Xiaojuan LI qi zhang Mengmeng LU Pengxin zhang Jie SONG Juan zhang Tao GUO Baolin ma Baiping Department of Pharmaceutical Sciences Beijing Institute of Radiation MedicineBeijing 100850China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China AnKang Chia Tai Pharmaceutical Co. Ltd.Shaanxi 725000China

Sixteen new dammarane-type triterpenoid saponins(1-16)featuring diverse structural variations in the side chain at C-17,along with twenty-one known analogues(17-37),have been isolated from the rhizomes of Gynostemma longipes ***,a plant renowned for its medicinal and edible *** structural elucidation of these compounds was accomplished through comprehensive analyses of 1D and 2D NMR and HRMS spectroscopic data,supplemented by comparison with previously reported *** assays on the isolates for their protective effects against hypoxia-induced damage in pheochromocytoma cells(PC12 cells)revealed that nine saponins exhibited significant anti-hypoxic *** investigation into the anti-hypoxia mechanisms of the representative saponins demonstrated that compounds 22 and 36 markedly reduced the levels of hypoxia-induced ***,these compounds were found to decrease the release of lactate dehydrogenase(LDH)and malondialdehyde(MDA),while increasing the activity of superoxide dismutase(SOD),thereby indicating that the saponins could mitigate hypoxia-induced injuries by ameliorating apoptosis and oxidative *** findings offer substantial evidence for the future utilization and development of ***,identifying dammarane-type triterpenoid saponins as its active anti-hypoxic constituents.

关键词： Gynostemma longipes Dammarane-type saponins Anti-hypoxia effect Apoptosis

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 13-23页

作者： Yue Yang Ze Fu qi zhang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science&TechnologyNanjing 210094China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresCollege of Engineering and Applied SciencesKey Laboratory of Intelligent Optical Sensing and Manipulation(Ministry of Education)Jiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

Oily wastewater from ocean oil spills endangers marine ecosystems and human health. Therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bottom-layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bottom “bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. Therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 W/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. This work provides a green and cost-effective path for the separation of oil-water mixtures.

关键词： Oily wastewater Carbonized wood Salinity gradient Electricity generation Solar irradiation