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Coupled strategy based on regulator manipulation and medium optimization empowers the biosynthetic overproduction of lincomycin

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Synthetic and Systems Biotechnology 2024年第1期9卷 134-143页

作者： Xinlu Cai Wanlian Xu Yang Zheng Sendi Wu Rundong Zhao Nian Wang Yaqian Tang Meilan Ke Qianjin Kang Linquan Bai Buchang Zhang Hang Wu School of Life Sciences Institute of Physical Science and Information TechnologyAnhui UniversityHefei230601China State Key Laboratory of Microbial Metabolism Shanghai Jiao Tong UniversityShanghai200240China

The biosynthesis of bioactive secondary metabolites,specifically antibiotics,is of great scientific and economic *** control of antibiotic production typically involves different processes and molecular *** numerous efforts to improve antibiotic yields,joint engineering strategies for combining genetic manipulation with fermentation optimization remain *** A(Lin-A),a lincosamide antibiotic,is industrially fermented by Streptomyces ***,the leucine-responsive regulatory protein(Lrp)-type regulator SLCG_4846 was confirmed to directly inhibit the lincomycin biosynthesis,whereas indirectly controlled the transcription of SLCG_2919,the first reported repressor in *** of SLCG_4846 in the high-yield *** LA219X(LA219XΔ4846)increases the Lin-A production and deletion of SLCG_2919 in LA219XΔ4846 exhibits superimposed yield *** the effect of the double deletion on cellular primary metabolism of ***,Plackett-Burman design,steepest ascent and response surface methodologies were utilized and employed to optimize the seed medium of this double mutant in shake flask,and Lin-A yield using optimal seed medium was significantly increased over the *** strategies were performed in a 15-L *** maximal yield of Lin-A in LA219XΔ4846-2919 reached 6.56 g/L at 216 h,55.1%higher than that in LA219X at the parental cultivation(4.23 g/L).This study not only showcases the potential of this strategy to boost lincomycin production,but also could empower the development of high-performance actinomycetes for other antibiotics.

关键词： Streptomyces Transcription factor Genetic engineering Fermentation optimization Lincomycin

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pH-Responsive polymer boosts cytosolic siRNA release for retinal neovascularization therapy

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Acta Pharmaceutica Sinica B 2024年第2期14卷 781-794页

作者： Shuai Guo Chunhui Li Changrong Wang Xiaowen Cao Xinyue Liu Xing-Jie Liang Yuanyu Huang Yuhua Weng School of Medical Technology Advanced Research Institute of Multidisciplinary ScienceSchool of Life ScienceKey Laboratory of Molecular Medicine and BiotherapyKey Laboratory of Medical Molecule Science and Pharmaceutics EngineeringBeijing Institute of TechnologyBeijing 100081China School of Pharmacy Shandong New Drug Loading&Release Technology and Preparation Engineering LaboratoryBinzhou Medical UniversityYantai 264003China School of Ophthalmology and Optometry School of Biomedical EngineeringThe Eye HospitalWenzhou Medical UniversityWenzhou 325027China Chinese Academy of Sciences(CAS) Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology of ChinaBeijing 100190China

Small interfering RNA(siRNA)has a promising future in the treatment of ocular diseases due to its high efficiency,specificity,and low toxicity in inhibiting the expression of target genes and ***,due to the unique anatomical structure of the eye and various barriers,delivering nucleic acids to the retina remains a significant *** this study,we rationally design PACD,an A-B-C type non-viral vector copolymer composed of a hydrophilic PEG block(A),a siRNA binding block(B)and a pH-responsive block(C).PACDs can self-assemble into nanosized polymeric micelles that compact siRNAs into polyplexes through simple *** evaluating its pH-responsive activity,gene silencing efficiency in retinal cells,intraocular distribution,and anti-angiogenesis therapy in a mouse model of hypoxia-induced angiogenesis,we demonstrate the efficiency and safety of PACD in delivering siRNA in the *** are surprised to discover that,the PACD/siRNA polyplexes exhibit remarkable intracellular endosomal escape efficiency,excellent gene silencing,and inhibit retinal *** study provides design guidance for developing efficient nonviral ocular nucleic acid delivery systems.

关键词： SiRNA Oculardeliverysystem Block polymer Endosomalescape Retinal neovascularization Blood-retinal barrier VEGFA Safety

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Theory and Method of Pulsed Ion Beam Single Crystal Silicon Reshaping Based on Controllable Time-varying Removal Function 7

Theory and Method of Pulsed Ion Beam Single Crystal Silicon ...

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7th Global Intelligent Industry Conference, GIIC 2024

作者： Liao, Rongjie Qiao, Tengduo Tian, Ziyao Wang, Yuyang Li, Guanlin Qiao, Dongyang Song, Ci Peng, Xing College of Intelligent Science and Technology National University of Defense Technology Hunan Changsha410073 China Hunan Provincial Key Laboratory of Ultra-Precision Machining Technology Hunan Changsha410073 China Laboratory of Science and Technology on Integrated Logistics Support Hunan Changsha410073 China

ISBN: (纸本)9781510682986

With the continuous improvement of optical performance requirements, weaponry, space observation, laser fusion, extreme ultraviolet lithography, and other fields of optical components of increasing precision requirements, the number of requirements is increasingly large, so the processing of optical components faces serious challenges. Pulsed Ion Beam Shaping is a non-contact optical component machining technology. Pulsed Ion Beam Shaping has the advantages of atomic-level machining accuracy and no edge effect. The ability of pulsed ion beam reshaping mainly depends on factors such as the stability of the removal function, the dynamic performance of the machine's motion axes, and the size of the removal function. At present, due to the difficulty of further improving the dynamic performance of the machine tool, a single beam diameter, and removal efficiency of the removal function for processing, trimming efficiency is not high, and can only be balanced according to the needs of trimming efficiency and accuracy. Thus, we proposed a pulsed ion beam reshaping processing method based on a controlled removal function to achieve the optimal beam diameter selected by the removal function according to the different reshaping face shapes, which improves the reshaping capability of the pulsed ion beam while reducing the additional material removal layer to ensure high processing efficiency. The main research on the shaping method based on the controlled time-varying removal function is carried out, the shaping model based on the controlled time-varying removal function and the residence time solution model are analyzed, the global optimization algorithm based on the error distribution of the surface shape and the removal function library, and the optimal combination of the removal function under the constraints is established, and the theory of the shaping of the controlled time-varying removal function is perfected, and the iterative genetic algorithms, variation and crosso

关键词： Extreme ultraviolet lithography

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Optimization Method of Scanning Strategy for Reactive Ion Beam Etching of Large Aperture Grating Elements 7

Optimization Method of Scanning Strategy for Reactive Ion Be...

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7th Global Intelligent Industry Conference, GIIC 2024

作者： Zhang, Bo Zhang, Longxiang Chang, Xuran Ma, Xunchang Zhang, Cheng Xiao, Wentong Shi, Feng Zhou, Gang Peng, Xing College of Intelligent Science and Technology National University of Defense Technology Hunan Changsha410073 China Hunan Provincial Key Laboratory of Ultra-Precision Machining Technology Hunan Changsha410073 China Laboratory of Science and Technology on Integrated Logistics Support Hunan Changsha410073 China

ISBN: (纸本)9781510682986

Large-scale two-dimensional gratings are typically produced using reactive ion beam scanning etching. However, this method is limited by uneven etching depth, which can negatively impact the performance of large-aperture gratings. To address this issue, we propose optimizing the scanning strategy during reactive etching to improve uniformity. Based on the specific beam distribution, we have established a row spacing calculation model using the convolution algorithm. In the actual reaction etching experiment, we found that a row spacing of only 16 mm resulted in a uniformity within the etching range of 600 mm that was better than 6%. This improvement enhances the diffraction uniformity of the grating. Simulation and experiment were used to verify the influence of row spacing on the uniformity of surface grooves during etching. This method was then used to significantly improve the uniformity of grating etching depth after processing. Therefore, the proposed optimization method of reactive etching scanning strategy has a good industrial application prospect for large-scale two-dimensional grating, wafer etching, and large-scale integrated circuit manufacturing. © 2024 SPIE.

关键词： Reactive ion etching

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Separation of chitin from shrimp shells enabled by transition metal salt aqueous solution and ionic liquid

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Chinese Journal of Chemical Engineering 2023年第1期53卷 133-141页

作者： Mi Feng Bin He Xinyan Chen Junli Xu Xingmei Lu Cai Jia Jian Sun Key Laboratory of Molecular Medicine and Biotherapy Ministry of Industry and Information TechnologySchool of Life SciencesBeijing Institute of TechnologyBeijing 100081China Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering Ministry of Industry and Information TechnologyAdvanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing 100081China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsState Key Laboratory of Biochemical EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical and Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Chitin is a widely used important industrial polymer mainly from shrimp shells, but its commercial preparation is under the great challenge of serious pollution due to the requirement of HCl and Na ***, we demonstrated that high purity chitin can be obtained from waste shrimp shells(WSSs) by cascade separation with transition metal salt aqueous solution and ionic liquid(IL). Firstly, calcium carbonate of WSSs was effectively removed in the metal salt aqueous solution driven by the ion exchange interaction. Subsequently, 1-butyl-3-methylimidazolium chloride([Bmim]Cl) had bifunctional abilities to remove residual protein and introduced metal salts simultaneously by hydrogen bonding and coordination interactions. The key experimental factors affecting the separation process were systematically studied, including the type of metal salts, temperature, and [Bmim]Cl loading. After sequential treatment with a 20%(mass) Ni SO4aqueous solution at 130 ℃ and [Bmim]Cl at 150 ℃, the purity of a-chitin can be up to 96.5%(mass) that meets commercial requirements. The use of metal salts with higher coordination ability makes the preparation of chitin no longer depend on the commonly acid-base reaction, which is conducive to the preservation of chitin structure.

关键词： Chitin Ionic liquids Transition metal salts Separation Sustainability

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MOF-derived La/ZnO–TiO2 composite with enhanced photocatalytic ability for degradation of tetracycline

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Progress in Natural science:Materials International 2023年第4期33卷 544-550页

作者： Lin Zhang Jun Chen Lai-Bo Song Jun-Jie Pan Qing Luo School of Physical and Healthy Education Jiangxi Science and Technology Normal University School of Chemistry and Environmental Engineering Wuhan Institute of Technology Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics-Hubei Bioinformatics&Molecular Imaging Key Laboratory Department of Biomedical Engineering College of Life Science and Technology Huazhong University of Science and Technology Chemical Biology Center Lishui Institute of Agriculture and Forestry Sciences College of Materials Xiamen University

Developing effective and stable photocatalysts for organic pollutants degradation are still a big challenge in practical water treatment now. In this work, La doped ZnO–TiO2composite（La/ZnO–TiO2） were successfully fabricated by using PVP modified ZIF-8/TiO2as template via the absorption and pyrolysis routes. All as-fabricated materials were analyzed by XRD, SEM, TEM, BET, XPS, UV–vis absorption spectra and ESR spectra. PVP modified ZIF-8/TiO2was fully transferred into ZnO–TiO2after being pyrolyzed at high temperature under air *** doping of La can make ZnO–TiO2exhibiting red-shifted, which is attributed to the capture of photo-generated electrons by La, leading to the effective separation between photo-generated electrons and holes. Furthermore,the photocatalytic performance of all as-fabricated materials were explored by degradation of tetracycline（TC）solution under UV light irradiation. La/ZnO–TiO2exhibits excellent stability. And the photocatalytic degradation rate of La/ZnO–TiO2is 99.2%, which is even higher than ZnO（87.4%）, ZnO–TiO2（87.4%）, P25（TiO2）(92.7%).More than that, the effect of catalyst's dose, effect of TC concentration and effect of pH for TC degradation have been well explored. The excellent photocatalytic performance of La/ZnO–TiO2makes it possible to be applied for degradation of organic pollutants in practice.

关键词： La/ZnO–TiO2 Red-shifted Effective separation Photocatalytic performance Tetracycline

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Comparative study on landslide susceptibility mapping based on different ratios of training samples and testing samples by using RF and FR-RF models

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Natural Hazards Research 2024年第1期4卷 62-74页

作者： Xu, Ke Zhao, Zhou Chen, Wei Ma, Jianquan Liu, Fei Zhang, Yihao Ren, Zijun College of Geology and Environment Xi'an University of Science and Technology Shaanxi Xi'an 710054 China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi'an University of Science and Technology Shaanxi Xi'an 710054 China

Evaluation of landslide susceptibility is essential to planning of land and space utilization. For this purpose, the paper presents a case study from Fugu County, Shaanxi Province, China. Firstly, the geological environment and current state of landslides in Fugu County were investigated. Then, slope, aspect, terrain relief, curvature, lithology, land type, and normalized difference vegetation index (NDVI) were considered as the landslide susceptibility condition factors, and the correlation between these carried out by using Multicollinearity Analysis method. Next, landslide and non-landslide samples were divided into training samples and testing samples according to the sample ratios of 8/2, 7/3, 6/4, and 5/5, respectively. The landslide susceptibility mapping was carried out by using Random Forest (RF) model and Frequency Ratio coupled with Random Forest (FR-RF) model, respectively. Lastly, the landslide density (LD), landslide frequency ratio (LFR), the area under the curve (AUC) of the receiver operator, and other indicators were used to validate the rationality, accuracy, and performance of the landslide susceptibility maps produced from different models and ratios. The results indicated that all maps are reasonable, except the map when ratio is 5/5. For each map, regardless of ratios, the LD and LFR are the greatest in the zones classed as having a very high susceptibility, followed by those with a high, moderate, low, and very low classes. In the Random Forest (RF) model, when the training test set is not at the same time its in the area of extremely high sensitivity of LD and the size of the FR value respectively 7/3 (201.026) > 8/2 (154.440) > 6/4 (93.696) >5/5 (136.364) and 7/3 (4.806) > 8/2 (3.692) > 6/4 (3.260) > 5/5 (2.240);in the Frequency Ratio coupled with Random Forest (FR-RF) model, Inall the training test sets the size of the proportion of LD and FR value respectively 7/3 (145.693) > 6/4 (127.151) > 5/5 (122.857) > 8/2 (113.263) a

关键词： Comparative study FR-RF model Landslide susceptibility RF model Sample ratio

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Recent progresses of exosome-liposome fusions in drug delivery

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Chinese Chemical Letters 2024年第2期35卷 107-117页

作者： Lulu Zheng Bo Hu Deyao Zhao Wenjing Liu Qing Liu Yuanyu Huang Shaobo Ruan School of Life Science Advanced Research Institute of Multidisciplinary ScienceSchool of Medical TechnologyKey Laboratory of Molecular Medicine and BiotherapyKey Laboratory of Medical Molecule Science and Pharmaceutics EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Radiation Oncology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000China Beijing Key Laboratory of Drug Resistance Tuberculosis Research Beijing Tuberculosis and Thoracic Tumor Research Instituteand Beijing Chest HospitalCapital Medical UniversityBeijing 101149China

Exosomes are membrane-bound nanoscale extracellular vesicles,which produced by almost all *** to the excellent biocompatibility,long circulation time as well as low immunogenicity,exosomes as naturally-derived drug delivery carriers have experienced explosive growth over the past ***,issues such as insufficient loading efficiency,heterogeneous delivery efficiency,uncontrollable targeting ability,and low production limit their wide ***,the emerging exosome-liposome fusion strategy has become a potential approach to solve such ***,this review mainly focuses on the currently developed exosome-liposome fusion strategy and their application in drug delivery as well as disease *** review aims to shed light on the advantages of fusion strategy in drug delivery and provides a better understanding for more rational *** current challenge and future perspective regarding their clinical translation and application will also be discussed.

关键词： Exosome Liposome Membrane fusion Drug delivery Disease treatment

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Recent advances on decomplexation mechanisms of heavy metal complexes in persulfate-based advanced oxidation processes

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Chinese Chemical Letters 2024年第6期35卷 146-154页

作者： Shili Wang Mamitiana Roger Razanajatovo Xuedong Du Shunli Wan Xin He Qiuming Peng Qingrui Zhang State Key Laboratory of Metastable Materials Science and Technology Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource ReuseYanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Agroecological Safetye Key Laboratory Hebei University of Environmental EngineeringQinhuangdao 066102China College of Life&Environment Sciences Huangshan UniversityHuangshan 245041China

In some industrial wastewater,heavy metals combine with organic complexing agents to form heavy metal complexes(HMCs).These HMCs can be difficult to decompose and remove through conventional techniques due to their higher stability than free heavy metal *** recent years,persulfate based advanced oxidation processes(PS-based AOPs)have been recognized as a viable technique for HMCs ***,a comprehensive and in-depth understanding of the relevant HMCs decomplexation mechanisms in PS-based AOPs is still *** review delineates the current progress of HMCs decomplexation in PS-based *** discuss the distinctions between the two widely used oxidant types in PS-based AOPs ***,we summarize and highlight the decomplexation mechanisms based on electron and energy transfer,and degradation pathways of *** also emphasize the effects of environmental water constituents,namely p H,inorganic ions,and natural organic matter(NOM),on HMCs ***,we identify the existing challenges and perspectives that will steer the direction of advancing PS-based AOPs to remove HMCs.

关键词： Heavy metal complexes Persulfate Advanced oxidation processes Decomplexation mechanisms Electron and energy transfer

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Single-cell transcriptomes provide insights into expansion of glial cells in Bombyx mori

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Insect science 2024年第4期31卷 1041-1054页

作者： Xiaojing Liu Zhongjie Zhang Bo Hu Kai Chen Ye Yu Hui Xiang Anjiang Tan Jiangsu Key Laboratory of Sericultural Biology and Biotechnology School of BiotechnologyJiangsu University of Science and TechnologyZhenjiangJiangsu ProvinceChina Key Laboratory of Silkworm and Mulberry Genetic Improvement Ministry of Agriculture and Rural AffairsThe Sericultural Research InstituteChinese Academy of Agricultural SciencesZhenjiangJiangsu ProvinceChina Guangzhou Key Laboratory of Insect Development Regulation and Application Research Institute of Insect Science and Technology and School of Life SciencesSouth China Normal UniversityGuangzhouChina

The diversity of cell types in the brain and how these change during different developmental stages,remains largely *** life cycle of insects is short and goes through 4 distinct stages including embryonic,larval,pupal,and adult *** postembryonic life,the larval brain transforms into a mature adult version after *** silkworm,Bombyx mori,is a lepidopteran model ***,we characterized the brain cell repertoire of larval and adult *** by obtaining 50708 single-cell *** and 12 cell clusters from larval and adult brains were assigned based on marker genes,*** cell types include Kenyon cells,optic lobe cells,monoaminergic neurons,surface glia,and astrocyte *** further assessed the cell type compositions of larval and adult *** found that the transition from larva to adult resulted in great expansion of glial *** glial cell accounted for 49.8%of adult midbrain *** to flies and ants,the mushroom body kenyon cell is insufficient in ***,which accounts for 5.4%and 3.6%in larval and adult brains,*** of neuropeptide expression showed that the abundance and specificity of expression varied among individual ***,we found that ion transport peptide was specifically expressed in glial cells of larval and adult *** cell atlas dataset provides an important resource to explore cell diversity,neural circuits and genetic profiles.

关键词： brain neuropeptide silkworm single-cell transcriptome

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