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Characterization of a LAL-type regulator NemR in nemadectin biosynthesis and its application for increasing nemadectin production in Streptomyces cyaneogriseus

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Science China(Life Sciences) 2019年第3期62卷 394-405页

作者： Chuang Li Hairong He Jiabin wang Hui Liu Haiyan wang Yajie Zhu xiangjing wang Yanyan Zhang Wensheng Xiang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences School of Life Science Northeast Agricultural University College of Food and Bioengineering Qiqihar University

Nemadectin, a macrocyclic lactone antibiotic, is produced by Streptomyces cyaneogriseus ssp. noncyanogenus. A methoxime derivative of nemadectin, moxdectin, has been widely used to control insect and helminth in animal health. Despite the importance of nemadectin, little attention has been paid to the regulation of nemadectin biosynthesis, which has hindered efforts to improve nemadectin production via genetic manipulation of regulatory genes. Here, we characterize the function of nemR, the cluster-situated regulatory gene encoding a LAL-family transcriptional regulator, in the nemadectin biosynthesis gene cluster of S. cyaneogriseus ssp. noncyanogenus NMWT1. NemR is shown to be essential for nemadectin production and found to directly activate the transcription of nemA1-1/A1-2/A2, nemC and nemA4/A3/E/D operons, but indirectly activate that of nemG and nemF. A highly conserved sequence 5′-TGGGGTGKATAGGGGGTA-3′(K=T/G) is verified to be essential for NemR ***, four novel targets of NemR, including genes encoding an SsgA-like protein(TU94_12730), a methylmalonyl-CoA mutase(TU94_19950), a thioesterase of oligomycin biosynthesis(TU94_22425) and a MFS family transporter(TU94_24835)are identified. Overexpression of nemR significantly increased nemadectin production by 79.9%, in comparison with NMWT1,suggesting that nemR plays an important role in the nemadectin biosynthesis.

关键词： nemadectin Streptomyces cyaneogriseus ssp.noncyanogenus nemR LAL overexpression

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Transcriptome-guided identification of a four-component system, SbrH1-R, that modulates milbemycin biosynthesis by influencing gene cluster expression, precursor supply, and antibiotic efflux

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Synthetic and Systems Biotechnology 2022年第2期7卷 705-717页

作者： Lan Ye Yanyan Zhang Shanshan Li Hairong He Guomin Ai xiangjing wang Wensheng Xiang School of Life Science Northeast Agricultural UniversityNo.59 Mucai StreetXiangfang DistrictHarbin150030China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijingChina College of Pharmacy Henan University of Chinese MedicineZhengzhou 450046HenanChina

Streptomyces can produce numerous antibiotics and many other bioactive ***,the molecular mechanisms of transcriptional regulators in control of antibiotic production by influencing the expression of biosynthetic gene clusters(BGCs)have been extensively ***,for regulators that affect both antibiotic production and cell growth,the way to influence antibiotic production may be diverse,but related studies are ***,based on time-course transcriptome analysis,a four-component system,SbrH1-R,consisting of the two-component system SbrKR(SBI_03479/3478)and two hypothetical proteins SbrH1(SBI_03481)and SbrH2(SBI_03480)potentially related with the biosynthesis of milbemycins was identified in Streptomyces bingchenggensis *** of sbrH1-R resulted in weakened cell growth but a 110%increase of milbemycin production compared with that in *** transcriptome analyses of the sbrH1-R mutant and BC-101-4 revealed that SbrH1-R not only indirectly represses milbemycin BGC expression,but also inhibits milbemycin production by modulating expression levels of genes related to precursor supply and antibiotic *** genetic experiments identified several new targets,including five precursor supply-associated reactions/pathways(e.g.,the reaction from pyruvate to acetyl-CoA,the reaction from acetyl-CoA to citrate,the fatty acidβ-oxidation process,and the branched chain amino acid and phenylalanine acid degradation pathways)and a milbemycin exporter system(MilEX2)that can be engineered for milbemycin *** results shed new light on the understanding of regulation of milbemycin biosynthesis and provide useful targets for future metabolic engineering of the native host to improve milbemycin production.

关键词： Milbemycins Streptomyces bingchenggensis SbrH1-R Precursor supply Milbemycin exporter Overproduction

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Hydrogen Production with High Evolution Rate and High Yield by Immobilized Cells of Hydrogen-producing Bacteria Strain B49 in a Column Reactor

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High Technology Letters 2002年第4期8卷 21-25页

作者：任南琪 wang xiangjing Xiang Wensheng Lin Ming Li Jianzheng Guo Wanqian School of Municipal & Environmental Engineering Harbin Institute of Technology Harbin 150090 P.R China Research Center of Life Science and Biotechnology Northeast Agricultural University Harbin 150030 P.R China

To improve the hydrogen evolution rate in continuous hydrogen production of a fermentative hydrogen-producing bacteria strain B49 (AF481148 in EMBL), 4% immobilized cells by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate in a column reactor obtain hydrogen yield of 2.31 mol H2/mol glucose and hydrogen evolution rate of 1435.4 ml/L culture·h respectively at medium retention time of 2 h with a medium containing l0 g glucose/L. As the cell density in gel beads is increased to 8%, hydrogen yield and hydrogen evolution rate for l0 g glucose/L are 2.34 mol H2/mol glucose and 2912.4 ml/L culture · h respectively at medium retention time of 1 h, and for molasses wastewater COD of 7505.9 mg/L hydrogen production potential of 205.6 ml/g COD and hydrogen evolution rate of 2057.7 ml/L culture·h at hydraulic retention time of 0.75 h are observed. In the continuous culture pH value keeps around 3.9 by self regulation.

关键词： hydrogen-producing bacteria strain B49,immobilized cells,continuous hydrogen production

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CMOS-compatible neuromorphic devices for neuromorphic perception and computing: a review

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International Journal of Extreme Manufacturing 2023年第4期5卷 292-312页

作者： Yixin Zhu Huiwu Mao Ying Zhu xiangjing wang Chuanyu Fu Shuo Ke Changjin Wan Qing Wan School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023People’s Republic of China Yongjiang Lab Ningbo 315201People’s Republic of China School of Micro-Nano Electronics Hangzhou Global Scientific and Technological Innovation CentreZhejiang University38 Zheda RoadHangzhou 310027People’s Republic of China

Neuromorphic computing is a brain-inspired computing paradigm that aims to construct efficient,low-power,and adaptive computing systems by emulating the information processing mechanisms of biological neural *** the core of neuromorphic computing are neuromorphic devices that mimic the functions and dynamics of neurons and synapses,enabling the hardware implementation of artificial neural *** types of neuromorphic devices have been proposed based on different physical mechanisms such as resistive switching devices and electric-double-layer *** devices have demonstrated a range of neuromorphic functions such as multistate storage,spike-timing-dependent plasticity,dynamic filtering,*** achieve high performance neuromorphic computing systems,it is essential to fabricate neuromorphic devices compatible with the complementary metal oxide semiconductor(CMOS)manufacturing *** improves the device’s reliability and stability and is favorable for achieving neuromorphic chips with higher integration density and low power *** review summarizes CMOS-compatible neuromorphic devices and discusses their emulation of synaptic and neuronal functions as well as their applications in neuromorphic perception and *** highlight challenges and opportunities for further development of CMOS-compatible neuromorphic devices and systems.

关键词： neuromorphic computing neuromorphic devices CMOS-compatible resistive switching device transistor

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Cytochrome P450 Monooxygenase Immobilization as a Model of Herbicide Metabolism in vitro

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High Technology Letters 2004年第2期10卷 9-12页

作者：向文胜 wang xiangjing Ju Xiulian Ren Tianrui Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 P.R.China Research Center of Life Science and Biotechnology Northeast Agricultural University Harbin 150030 P.R.China Research Center of Life Science and Biotechnology Northeast Agricultural University Harbin 150030 P.R.China Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 P.R.China

To investigate herbicide metabolism in vitro by cytochrome P450 with stable enzymatic activity, cytochrome P450 is immobilized in silk fibroin. The enzymatic activity of immobilized cytochrome P450 is maintained above 80% after repeated batch experiments for 10 times. Moreover, the enzymatic activity of immobilized cytochrome P450 is kept as relatively high as 73.8% after storage for two months at 4℃. In addition, immobilization can improve the temperature and pH stability of cytochrome P450. Immobilized cytochrome P450 has the similar affinity Km values for herbicide chlorsulfuron and triasulfuron as the free cytochrome P450. In the case of chlorosulfuron, affinity Km value is 53μmol/L for free cytochrome P450, and 63μmol/L for immobilized cytochrome P450, respectively. In the case of triasulfuron affinity, Km value is 36μmol/L for free cytochrome P450, and 44μmol/L for immobilized cytochrome P450, respectivily. Immobilized cytochrome P450 will be convenient, rapid, stable and continuous for herbicide metabolism in micro-bioreactor in vitro.

关键词：细胞色素 P450 单氧酶除草剂新陈代谢固定作用

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Improvement of Ramoplanin Production by Mutation and Medium Optimization

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Journal of Northeast Agricultural University(English Edition) 2008年第1期15卷 18-22页

作者： WU Xiangjin wang xiangjing SHI Yingzi XIANG Wensheng BAI Hua College of Life Sciences Northeast Agricultural University Harbin 150030 China Zhejiang Hisun Pharmaceutical Co. Ltd. Taizhou 318000 Zhejiang China

The aim of this work was to develop a mutation and selection procedure to select the high-yield strain, and this strain could alleviate the inhibition in the biosynthesis of ramoplanin caused by L-leucine. In this experiment, the strain Actinoplanes sp. C6-78-14 that produced 384.8 mg of total productivity per liter was isolated. Its ramoplanin productivity was 4.13-fold higher than that of the parent strain A ctinoplanes sp. C2-9-45. The subculture experiments showed that the hereditary character of C6-78-14 was stable. Subsequent media studies with strain Actinoplanes sp. C6-78-14 showed that adding 0.001% FeSO4· 7H2O, 0.001% CoCl2· 6H2O and 0.001% CuSO4· 5H2O to fermentation medium respectively could enhance the ramoplanin production, and the production of each group was increased by 10%, 15% and 20% compared with the control group.

关键词： ramoplanin 4-aza-leucine mutation fermentation

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星载大气主要温室气体监测仪杂光模拟分析

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红外与激光工程 2015年第2期44卷 616-619页

作者：李双裘桢炜王相京中国科学院安徽光学精密机械研究所光学遥感中心中国科学院通用光学定标与表征技术重点实验室安徽合肥230031

杂散光分析是提高信噪比,保证测量精度的关键手段之一。依据星载大气主要温室气体监测仪光学系统结构及其工作特点,设计了仪器的外遮光罩和前置望远系统的遮光筒。建立仪器的三维实体模型,利用Tracepro软件对仪器氧气通道（758~768 nm... 详细信息

杂散光分析是提高信噪比,保证测量精度的关键手段之一。依据星载大气主要温室气体监测仪光学系统结构及其工作特点,设计了仪器的外遮光罩和前置望远系统的遮光筒。建立仪器的三维实体模型,利用Tracepro软件对仪器氧气通道（758~768 nm）的杂散光进行了分析,给出系统杂散光点源透射比（PST,Point Source Transmittance）曲线,PST在30°离轴角小于5×10-7。依据PST拟合曲线,通过积分计算得到杂散光系数小于4%。结果表明：杂散光抑制措施效果明显,杂散光水平达到了设计指标要求。

关键词：空间外差光谱仪杂散光遮光罩点源透射比

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Improvement of spergualin production by mutation and medium optimization

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Journal of Northeast Agricultural University(English Edition) 2007年第4期14卷 310-313页

作者： SHI Yingzi MA Guangpeng WU Xiangjin JIANG Ling wang xiangjing BAI Hua College of Life Sciences Northeast Agricultural University Harbin 150030 China China Rural Technology Development Center Beijing 100862 China Zhejiang Hisun Pharmaceutical Co. Ltd. Taizhou 318000 Zhejiang China

In order to screen a high-yield spergualin-production strain and an optimal fermentation medium, large numbers of isolates were selected after ultraviolet （UV） mutation and self-tolerant mutation of Bacillus laterosporus A7. A high-yield strain A-94-7 was obtained and the spergualin productivity was 4. 1-fold of the parent strain. The genetic stability of the high-yield strain Bacillus laterosporus A-94-7 was very good. Aider fermentation medium optimization, Bacillus laterosporus A-94-7 was able to produce 380 mg· L^-1 The spergualin productivity in Bacillus laterosporus A7 was increased 4.75-fold by mutation and medium optimization.

关键词： spergualin Bacillus laterosporus self-tolerant mutation medium optimization

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组合型生态浮床中各生物单元对污染物去除的贡献及净化机理

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土木建筑与环境工程 2012年第4期34卷 136-141页

作者：王国芳汪祥静吴磊李先宁东南大学能源与环境学院南京210096 东南大学环境医学工程教育部重点实验室南京210096

对组合型生态浮床中水生植物单元(空心菜)、水生动物单元(滤食性贝类三角帆蚌)、微生物强化单元(人工介质)进行组合配置,分析不同生物单元的污染物去除贡献率,试验结果表明,组合型生态浮床中人工介质单元对TN、TP、CODMn去除的贡献率分... 详细信息

对组合型生态浮床中水生植物单元(空心菜)、水生动物单元(滤食性贝类三角帆蚌)、微生物强化单元(人工介质)进行组合配置,分析不同生物单元的污染物去除贡献率,试验结果表明,组合型生态浮床中人工介质单元对TN、TP、CODMn去除的贡献率分别为48.5%、46.7%、49.9%,均高于水生植物和水生动物单元,人工介质富集的微生物是氮磷等污染物的净化主体,而水生动物单元对Chl-a的去除贡献率达到了79.1%,表明水生动物单元的污染物去除途径主要为三角帆蚌对藻类等颗粒性有机物的滤食。通过三角帆蚌的滤食及排氨作用促进了颗粒有机物的可溶化和无机化,为组合型生态浮床中人工介质上微生物增殖以及植物的吸收提供了有利的基质条件,从而促进了浮床的污染物净化效能。

关键词：生态浮床三角帆蚌人工介质贡献率净化强化机理

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超低功耗尖峰视锥感受器及其颜色感知应用

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科学通报 2023年第35期68卷 4751-4753页

作者：王祥静万昌锦万青南京大学电子科学与工程学院南京210023

传统机器视觉依赖于CMOS/CCD图像传感器获取视觉信息,并依赖于冯·诺依曼架构的计算机处理这些信息.这种信息获取模式是由人工创建的同步计时和控制信号进行驱动和控制的,这些人工创建的信号与视觉信息的来源及其动态没有任何关联性,因... 详细信息

传统机器视觉依赖于CMOS/CCD图像传感器获取视觉信息,并依赖于冯·诺依曼架构的计算机处理这些信息.这种信息获取模式是由人工创建的同步计时和控制信号进行驱动和控制的,这些人工创建的信号与视觉信息的来源及其动态没有任何关联性,因而包含大量的低特征密度的信息.而生物系统中视觉的形成是由视网膜上的光感受器接收光强和颜色信息,并将其转化为尖峰电位传入视神经且送至大脑的视觉皮层进行感知处理[1].

关键词：颜色信息机器视觉超低功耗 CCD图像传感器冯·诺依曼控制信号视觉信息光感受器

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