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| 1 | V2X Offloading and Resource Allocation in SDN-Assisted MEC-Based Vehicular Networks显示文摘As an important application scenario of 5G, the vehicular network has a huge amount of computing data, which brings challenges to the scarce network resources. Mobile edge computing(MEC) sinks cloud services to the edge of network, which reduces the delay jitter caused by remote cloud computing. Software-defined networking(SDN) is an emerging network paradigm with the features of logic centralized control and programmability. In this paper, we construct an SDN-assisted MEC network architecture for the vehicular network. By introducing SDN controller, the efficiency and flexibility of vehicular network are improved, and the network state can be perceived from the global perspective. To further reduce the system overhead, the problem of vehicle to everything(V2X) offloading and resource allocation is proposed, where the optimal offloading decision, transmission power control, subchannels assignment, and computing resource allocation scheme are given. The optimization problem is transformed into three stages because of the heterogeneity of the offloaded tasks and the NP-hard property of the problem. Firstly, the analytic hierarchy process is used to select initial offloading node, then stateless Q-learning is adopted to allocate transmission power, subchannels and computing resources. In addition, the offloading decision is modeled as a potential game, and the Nash equilibrium is proved by the potential function construction. Finally, the numerical results show that the proposed mechanism can effectively reduce the system overhead and achieve better results compared with others’ algorithms. | Haibo Zhang Zixin Wang Kaijian Liu | 2020 | China Communications2020，17，5： | 12 |
| 2 | MicroTom Metabolic Network: Rewiring Tomato Metabolic Regulatory Network throughout the Growth Cycle显示文摘Tomato(Solanum lycopersicum)is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research.Although many research efforts have focused on the analysis of metabolite differences between varieties and species,the dynamics of metabolic changes during the tomato growth cycle and the regulatory networks that underlie these changes are poorly understood.In this study,we integrated high-resolution spatio-temporal metabolome and transcriptome data to systematically explore the metabolic landscape across 20 major tomato tissues and growth stages.In the resulting MicroTom Metabolic Network,the 540 detected metabolites and their co-expressed genes could be divided into 10 distinct clusters based on their biological functions.Using this dataset,we constructed a global map of the major metabolic changes that occur throughout the tomato growth cycle and dissected the underlying regulatory network.In addition to verifying previously well-established regulatory networks for important metabolites,we identified novel transcription factors that regulate the biosynthesis of important secondary metabolites such as steroidal glycoalkaloids and flavonoids.Our findings provide insights into spatiotemporal changes in tomato metabolism and generate a valuable resource for the study of metabolic regulatory processes in model plants. | Yan Li Yang Chen Lu Zhou Shengjie You Heng Deng Ya Chen Saleh Alseekh Yong Yuan Rao Fu Zixin Zhang Dan Su Alisdair R.Fernie Mondher Bouzayen Tao Ma Mingchun Liu Yang Zhang | 2020 | Molecular Plant2020，13，8： | 10 |
| 3 | Qualitative analysis of chemical components in Lianhua Qingwen capsule by HPLC-Q Exactive-Orbitrap-MS coupled with GC-MS显示文摘The Lianhua Qingwen(LHQW) capsule is a popular traditional Chinese medicine for the treatment of viral respiratory diseases.In particular,it has been recently prescribed to treat infections caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).However,due to its complex composition,little attention has been directed toward the analysis of chemical constituents present in the LHQW capsule.This study presents a reliable and comprehensive approach to characterizing the chemical constituents present in LHQW by high-performance liquid chromatography-Q Exactive-Orbitrap mass spectrometry(HPLC-Q Exactive-Orbitrap-MS) coupled with gas chromatography-mass spectrometry(GC-MS).An automated library alignment method with a high mass accuracy(within 5 ppm) was used for the rapid identification of compounds.A total of 104 compounds,consisting of alkaloids,flavonoids,phenols,phenolic acids,phenylpropanoids,quinones,terpenoids,and other phytochemicals,were successfully characterized.In addition,the fragmentation pathways and characteristic fragments of some representative compounds were elucidated.GC-MS analysis was conducted to characterize the volatile compounds present in LHQW.In total,17 compounds were putatively characterized by comparing the acquired data with that from the NIST library.The major constituent was menthol,and all the other compounds were terpenoids.This is the first comprehensive report on the identification of the major chemical constituents present in the LHQW capsule by HPLC-Q Exactive-Orbitrap-MS,coupled with GCMS,and the results of this study can be used for the quality control and standardization of LHQW capsules. | Shuai Fu Rongrong Cheng Zixin Deng Tiangang Liu | 2021 | Journal of Pharmaceutical Analysis2021，11，6： | 8 |
| 4 | Clinical features and the traditional Chinese medicine therapeutic characteristics of 293 COVID-19 inpatient cases显示文摘Coronavirus disease 2019 (COVID-19) is now pandemic worldwide and has heavily overloaded hospitals in Wuhan City, China during the time between late January and February. We reported the clinical features and therapeutic characteristics of moderate COVID-19 cases in Wuhan that were treated via the integration of traditional Chinese medicine (TCM) and Western medicine. We collected electronic medical record (EMR) data, which included the full clinical profiles of patients, from a designated TCM hospital in Wuhan. The structured data of symptoms and drugs from admission notes were obtained through an information extraction process. Other key clinical entities were also confirmed and normalized to obtain information on the diagnosis, clinical treatments, laboratory tests, and outcomes of the patients. A total of 293 COVID-19 inpatient cases, including 207 moderate and 86 (29.3%) severe cases, were included in our research. Among these cases, 238 were discharged, 31 were transferred, and 24 (all severe cases) died in the hospital. Our COVID-19 cases involved elderly patients with advanced ages (57 years on average) and high comorbidity rates (61%). Our results reconfirmed several well-recognized risk factors, such as age, gender (male), and comorbidities, as well as provided novel laboratory indications (e.g., cholesterol) and TCM-specific phenotype markers (e.g., dull tongue) that were relevant to COVID-19 infections and prognosis. In addition to antiviral/antibiotics and standard supportive therapies, TCM herbal prescriptions incorporating 290 distinct herbs were used in 273 (93%) cases. The cases that received TCM treatment had lower death rates than those that did not receive TCM treatment (17/273= 6.2% vs. 7/20= 35%, P = 0.0004 for all cases;17/77= 22% vs. 7/9= 77.7%, P = 0.002 for severe cases). The TCM herbal prescriptions used for the treatment of COVID-19 infections mainly consisted of Pericarpium Citri Reticulatae, Radix Scutellariae, Rhizoma Pinellia, and their combinations, which reflected the practical TCM principles (e.g., clearing heat and dampening phlegm). Lastly, 59% of the patients received treatment, including antiviral, antibiotics, and Chinese patent medicine, before admission. This situation might have some effects on symptoms, such as fever and dry cough. By using EMR data, we described the clinical features and therapeutic characteristics of 293 COVID-19 cases treated via the integration of TCM herbal prescriptions and Western medicine. Clinical manifestations and treatments before admission and in the hospital were investigated. Our results preliminarily showed the potential effectiveness of TCM herbal prescriptions and their regularities in COVID-19 treatment. | Zixin Shu Yana Zhou Kai Chang Jifen Liu Xiaojun Min Qing Zhang Jing Sun Yajuan Xiong Qunsheng Zou Qiguang Zheng Jinghui Ji Josiah Poon Baoyan Liu Xuezhong Zhou Xiaodong Li | 2020 | Frontiers of Medicine2020，14，6： | 7 |
| 5 | Quantitative method for evaluating detailed volatility of wind power at multiple temporal-spatial scales显示文摘With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to evaluate the volatility of wind power only consider its overall characteristics, such as the standard deviation of wind power, the average of power variables, etc., while ignoring the detailed volatility of wind power, that is, the features of the frequency distribution of power variables. However, how to accurately describe the detailed volatility of wind power is the key foundation to reduce its adverse influences. To address this, a quantitative method for evaluating the detailed volatility of wind power at multiple temporal-spatial scales is proposed. First, the volatility indexes which can evaluate the detailed fluctuation characteristics of wind power are presented, including the upper confidence limit, lower confidence limit and confidence interval of power variables under the certain confidence level. Then, the actual wind power data from a location in northern China is used to illustrate the application of the proposed indexes at multiple temporal(year–season–month–day) and spatial scales(wind turbine–wind turbines–wind farm–wind farms) using the calculation time windows of 10 min, 30 min, 1 h, and 4 h. Finally, the relationships between wind power forecasting accuracy and its corresponding detailed volatility are analyzed to further verify the effectiveness of the proposed indexes. The results show that the proposed volatility indexes can effectively characterize the detailed fluctuations of wind power at multiple temporal-spatial scales. It is anticipated that the results of this study will serve as an important reference for the reserve capacity planning and optimization dispatch in the electric power system which with a high proportion of renewable energy. | Yongqian Liu Han Wang Shuang Han Jie Yan Li Li Zixin Chen | 2019 | Global Energy Interconnection2019，2，4： | 5 |
| 6 | Characterization of the positive SARP family regulator PieR for improving piericidin A1 production in Streptomyces piomogeues var.Hangzhouwanensis显示文摘Piericidin A1,a member ofɑ-pyridone antibiotic,exhibits various biological activities such as antimicrobial,antifungal,and antitumor properties and possesses potent respiration-inhibitory activity against insects due to its competitive binding capacity to mitochondrial complex I.The biosynthetic pathway of piericidin A1 has been reported in Streptomyces piomogeues var.Hangzhouwanensis,while the regulatory mechanism remains poorly understood.In this study,a Streptomyces antibiotic regulatory protein(SARP)family transcriptional regulator PieR was characterized.Genetic disruption and complementation manipulations revealed that PieR positively regulated the production of piericidin A1.Moreover,the overexpression of pieR contributed to the improvement of piericidin A1 productivity.The real-time quantitative PCR(RT-qPCR)was carried out and the data showed that pieR stimulated the transcription of all the biosynthesis-related genes for piericidin A1.In order to explore the regulatory mechanism,electrophoresis mobility shift assays(EMSA)and DNase I footprinting experiments have been conducted.A protected region covering 50 nucleotides within the upstream region of pieR was identified and two 5-nt direct repeat sequences(5′-CCGGA-3′)in the protected region were found.These findings,taken together,set stage for transcriptional control engineering in the view of optimizing piericidin A1 production and thus provide a viable potent route for the construction of strains with high productivity. | Yan Li Lingxin Kong Jufang Shen Qing Wang Qian Liu Weinan Yang Zixin Deng Delin You | 2019 | Synthetic and Systems Biotechnology2019，4，1： | 4 |
| 7 | Streptomyces avermitilis industrial strain as cell factory for Ivermectin B1a production显示文摘Ivermectin,a kind of valuable derivatives of Avermectin,is distinct from Avermectin due to the saturated bond at C22eC23 position.Combinatorial biosynthesis of Ivermectins based on Avermectins biosynthetic gene cluster(ave)has been achieved recently,while the establishment of an Ivermectin homogeneous component producing strain is challenging because of the limited compatibility between the native and heterologous polyketide synthase(PKS)domains.In this study,the PKS module 2 Dehydratase(DH)-Enoylreductase(ER)-Ketoreductase(KR)domain set of Meilingmycin,which is another naturally occurring homologue of Avermectin,was employed to substitute the DH-KR domains of Avermectins PKS module 2 to generate an Ivermectin biosynthetic gene cluster(ive).Ivermectins B1a and A1a were heterologously biosynthesized in a classic actinomyces host Streptomyces lividans.The Avermectin B1a high-producing strain S.avermitilis 3-115 was genetically engineered to give an artificial host cell and Ivermectin B1a single component was effectively produced with a production of 1.25±0.14 g/L. | Qian Deng Liqiongzi Xiao Yang Liu Lixin Zhang Zixin Deng Changming Zhao | 2019 | Synthetic and Systems Biotechnology2019，4，1： | 3 |
| 8 | Mesozoic–Cenozoic Tectonic Evolution and Uplift in Pamir:Application of Fission Track Thermochronology显示文摘The Pamir Plateau can be divided into three secondary tectonic units from north to south:the North,the Middle and the South Pamir Blocks.The North Pamir Block belonged to the southern margin of Tarim-Karakum,thermochronological study of the Pamir structural intersection indicates that accretion of the Middle Pamir Block to the Eurasian Continental Margin and its subduction and collision with the North Pamir Block occurred in the Middle–Late Jurassic.Due to the Neo-Tethys closure in the Early Cretaceous,the South Pamir Block began to collide with the accretion(the Middle Pamir Block)of the Eurasian Continental Margin.Affected by the collision and continuous convergence between the Indian Plate and the Eurasian Plate since the Cenozoic,Pamir is in a multi-stage differential uplift process.During 56.1–48.5 Ma,North Pamir took the lead in uplifting,that is,the first rapid uplift in the Pamir region began there.The continuous compression and contraction of the Indian and Eurasian plates during 22.0–15.1 Ma forced the Pamir tectonic syntaxis to begin its overall uplift,i.e.Pamir began to enter the second rapid uplift stage in the Early Oligocene,which lasted until the Middle Miocene.During 14.6–8.5Ma,South Pamir was in a rapid uplift stage,while North Pamir was in a relatively stable state,showing asymmetry of tectonic deformation in the Pamir region in space.Since 6.5 Ma,Pamir began to rapidly uplift again. | FAN Baocheng LIU Mingyi HE Zixin MENG Guanglu WU Huanhuan LI Lu | 2021 | Acta Geologica Sinica(English Edition)2021，95，3： | 3 |
| 9 | Analysis and prediction of loudspeaker large-signal symptoms显示文摘Nonlinear lumped-parameter force factor Bl(x), stiffness Kms(x) and inductance Le(x) of electrodynamic loudspeakers change frequency responses and generate some nonlinear effects for large stimulus: harmonic and intermodulation distortion, DC component in diaphragm displacement, instability of vibration and jumping effects. By modeling the nonlinear system under large-signal conditions, relationship between the nonlinear parameters and large-signal behavior can be revealed and help to provide guidance to diagnose loudspeakers. Agreement between the measured and predicted responses of a real loudspeaker validates the modeling and enables new methods for loudspeaker diagnosis. | HENG Wei SHEN Yong XIA Jie FENG ZiXin LIU YunFeng | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，7： | 3 |
| 10 | Puromycin A, B and C, cryptic nucleosides identified from Streptomyces alboniger NRRL B-1832 by PPtase-based activation显示文摘Natural product discovery is pivot for drug development,however,this endeavor is often challenged by the wide inactivation or silence of natural products biosynthetic pathways.We recently developed a highly efficient approach to activate cryptic/silenced biosynthetic pathways through augmentation of the phosphopantetheinylation of carrier proteins.By applying this approach in the Streptomyces alboniger NRRL B-1832,we herein identified three cryptic nucleosides products,including one known puromycin A and two new derivatives(puromycin B and C).The biosynthesis of these products doesn't require the involvement of carrier protein,indicating the phosphopantetheinyl transferase(PPtase)indeed plays a fundamental regulatory role in metabolites biosynthesis.These results demonstrate that the PPtasebased approach have a much broader effective scope than the previously assumed carrier proteininvolving pathways,which will benefit future natural products discovery and biosynthetic studies. | Xiaoli Yan Benyin Zhang Wenya Tian Qi Dai Xiaoqin Zheng Ke Hu Xinxin Liu Zixin Deng Xudong Qu | 2018 | Synthetic and Systems Biotechnology2018，3，1： | 3 |
| 11 | In vitro reconstitution guide for targeted synthetic metabolism of chemicals, nutraceuticals and drug precursors显示文摘With the developments in metabolic engineering and the emergence of synthetic biology,many breakthroughs in medicinal,biological and chemical products as well as biofuels have been achieved in recent decades.As an important barrier to traditional metabolic engineering,however,the identification of ratelimiting step(s)for the improvement of specific cellular functions is often difficult.Meanwhile,in the case of synthetic biology,more and more BioBricks could be constructed for targeted purposes,but the optimized assembly or engineering of these components for high-efficiency cell factories is still a challenge.Owing to the lack of steady-state kinetic data for overall flux,balancing many multistep biosynthetic pathways is time-consuming and needs vast resources of labor and materials.A strategy called targeted engineering is proposed in an effort to solve this problem.Briefly,a targeted biosynthetic pathway is to be reconstituted in vitro and then the contribution of cofactors,substrates and each enzyme will be analyzed systematically.Next is in vivo engineering or de novo pathway assembly with the guidance of information gained from in vitro assays.To demonstrate its practical application,biosynthesis pathways for the production of important products,e.g.chemicals,nutraceuticals and drug precursors,have been engineered in Escherichia coli and Saccharomyces cerevisiae.These cases can be regarded as concept proofs indicating targeted engineering might help to create high-efficiency cell factories based upon constructed biological components. | Gao-Yi Tan Faying Zhu Zixin Deng Tiangang Liu | 2016 | Synthetic and Systems Biotechnology2016，1，1： | 3 |
| 12 | The Role of Biochar to Enhance Anaerobic Digestion: A Review显示文摘Biochar,one of the products of thermochemical conversion of biomass,possesses specific physiochemical properties such as conductivity,pore adsorption,surface functional groups,and cation exchange capacity.Anaerobic digestion(AD)as a classical bio-wastes conversion technology,suffers from inhibitions,process instability,and methanogenic inefficiency which limit its efficiency.With the advantages of pH buffering,functional microbes enrichment,inhibitors alleviating,and direct interspecies electron transfer(DIET)accelerating,biochar suggests a promising application as additives for AD.Herein,this paper reviewed the noting physicochemical properties of biochar,and discussed its roles and related mechanisms in AD.Further,this paper highlighted the advantages and drawbacks,and pointed out the corresponding challenges and prospects for future research and application of biochar amending AD. | Shuai Tang Zixin Wang Zhidan Liu Yuanhui Zhang Buchun Si | 2020 | Journal of Renewable Materials2020，8，9： | 2 |
| 13 | Nonlinear behavior of electrodynamic loudspeaker suspension at low frequencies显示文摘The suspension of electrodynamic loudspeakers includes a surround of the cone and a spider, and it is characterized by the mechanic stiffness in the lumped-parameter model. By solving the nonlinear differential equation of motion which considers the nonlinearity of suspension at low frequencies numerically and measuring different kinds of surrounds and spiders, the nonlinear behavior of suspension is theoretically and experimentally studied. Since the nonlinear stiffness of spiders and surrounds can be measured and fitted respectively before assembled into loudspeakers, which spider works best with which surround is studied. The performance of loudspeakers such as harmonic distortion based on the nonlinear parameters can be predicted. | FENG ZiXin SHEN Yong HENG Wei LIU YunFeng | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，7： | 2 |
| 14 | Revolution of vitamin E production by starting from microbial fermented farnesene to isophytol显示文摘Vitamin E is one of the most widely used vitamins.In the classical commercial synthesis of vitamin E(a-tocopherol),the chemical synthesis of isophytol is the key technical barrier.Here,we establish a new process for isophytol synthesis from microbial fermented farnesene.To achieve an efficient pathway for farnesene production,Saccharomyces cerevisiae was selected as the host strain.First,b-farnesene synthase genes from different sources were screened,and through protein engineering and system metabolic engineering. | Ziling Ye Bin Shi Yanglei Huang Tian Ma Zilei Xiang Ben Hu Zhaolin Kuang Man Huang Xiaoying Lin Zhu Tian Zixin Deng Kun Shen Tiangang Liu | 2022 | The Innovation2022，3，3： | 2 |
| 15 | SynBioEcoli: a comprehensive metabolism network of engineered E. coil in three dimensional visualization显示文摘设计 E 的一个全面新陈代谢网络。coli 在系统生物学是很重要的, metabolomics 学习。许多工具集中于二维的空格在新陈代谢的网络显示小径。然而,三维的可视化的用法可以帮助更好理解新陈代谢、规章的网络的复杂拓扑学。方法我们手工地从文学的大量试验性的数据(包括的小径,反应和代谢物) 与设计 E 的不同类型联系了的 curated。coli 然后利用了三维的可视化的一种新奇技术开发一个全面新陈代谢的网络命名 SynBioEcoli。结果 SynBioEoli 包含 740 条 biosynthetic 小径, 3,889 新陈代谢的反应, 2,255 化学药品手工地从与设计 E 的不同类型联系的大约 11,000 份新陈代谢出版物加重 curated。coli。而且, SynBioEcoli 与各种各样的信息科学技术集成。结论 SynBioEcoli 能被认为是设计 E 的全面 knowledgebase。coli 并且代表下一代细胞的新陈代谢网络可视化技术。它能经由浏览器被存取(例如 Google 铬) 支持 WebGL,在 http://www.rxnfinder.org/synbioecoli/ 。 | Weizhong Tu Shaozhen Ding Ling Wu Zhe Deng Hui Zhu Xiaotong Xu Chen Lin Chaonan Ye Minlu Han Mengna Zhao Juan Liu Zixin Deng Junni Chen Dong-Qing Wei Qian-Nan Hu | 2017 | Frontiers of Electrical and Electronic Engineering in China2017，5，1： | 2 |
| 16 | CmBES1 is a regulator of boundary formation in chrysanthemum ray florets显示文摘Chrysanthemum(Chrysanthemum morifolium)is an ideal model species for studying petal morphogenesis because of the diversity in the flower form across varieties;however,the molecular mechanisms underlying petal development are poorly understood.Here,we show that the brassinosteroid transcription factor BRI1-EMS-SUPPRESSOR 1(CmBES1)in chrysanthemum(C.morifolium cv.Jinba)is important for organ boundary formation because it represses organ boundary identity genes.Chrysanthemum plants overexpressing CmBES1 displayed increased fusion of the outermost ray florets due to the loss of differentiation of the two dorsal petals,which developed simultaneously with the ventral petals.RNA-seq analysis of the overexpression lines revealed potential genes and pathways involved in petal development,such as CUP-SHAPED COTYLEDON(CUC2),CYCLOIDEA 4(CYC4),genes encoding MADS-box transcription factors and homeodomain-leucine zippers(HD-Zips)and auxin pathway-related genes.This study characterizes the role of CmBES1 in ray floret development by its modulation of flower development and boundary identity genes in chrysanthemum. | Peilei Cheng Yanan Liu Yiman Yang Hong Chen Hua Cheng Qian Hu Zixin Zhang Jiaojiao Gao Jiaxin Zhang Lian Ding Weimin Fang Sumei Chen Fadi Chen Jiafu Jiang | 2020 | Horticulture Research2020，7，1： | 2 |
| 17 | The over-expression of a chrysanthemum gene encoding an RNA polymerase II CTD phosphatase-like 1 enzyme enhances tolerance to heat stress显示文摘The enzyme RNAPII CTD phosphatase-like 1 is known as a transcriptional regulator of the plant response to various abiotic stresses.Here,the isolation of CmCPL1,a chrysanthemum(Chrysanthemum morifolium)gene encoding this enzyme is described.Its predicted 955 residue gene product includes the FCPH catalytic domain,two double-stranded RNA binding motifs,and a nuclear localization signal.A sub-cellular localization assay confirmed that CmCPL1 was expressed in the nucleus.CmCPL1 transcription was shown to be significantly inducible by heat stress.The over-expression and knockdown of CmCPL1,respectively,increased and diminished the tolerance of chrysanthemum to heat stress,which maybe dependent on the regulation of CmCPL1 and on the expression of downstream heat stress-responsive genes. | Yuying Qi Yanan Liu Zixin Zhang Jiaojiao Gao Zhiyong Guan Weimin Fang Sumei Chen Fadi Chen Jiafu Jiang | 2018 | Horticulture Research2018，5，1： | 2 |
| 18 | Development of Streptomyces sp. FR-008 as an emerging chassis显示文摘Microbial-derived natural products are important in both the pharmaceutical industry and academic research.As the metabolic potential of original producer especially Streptomyces is often limited by slow growth rate,complicated cultivation profile,and unfeasible genetic manipulation,so exploring a Streptomyces as a super industrial chassis is valuable and urgent.Streptomyces sp.FR-008 is a fast-growing microorganism and can also produce a considerable amount of macrolide candicidin via modular polyketide synthase.In this study,we evaluated Streptomyces sp.FR-008 as a potential industrial-production chassis.First,PacBio sequencing and transcriptome analyses indicated that the Streptomyces sp.FR-008 genome size is 7.26 Mb,which represents one of the smallest of currently sequenced Streptomyces genomes.In addition,we simplified the conjugation procedure without heat-shock and pre-germination treatments but with high conjugation efficiency,suggesting it is inherently capable of accepting heterologous DNA.In addition,a series of promoters selected from literatures was assessed based on GusA activity in Streptomyces sp.FR-008.Compared with the common used promoter ermE*-p,the strength of these promoters comprise a library with a constitutive range of 60e860%,thus providing the useful regulatory elements for future genetic engineering purpose.In order to minimum the genome,we also target deleted three endogenous polyketide synthase(PKS)gene clusters to generate a mutant LQ3.LQ3 is thus an“updated”version of Streptomyces sp.FR-008,producing fewer secondary metabolites profiles than Streptomyces sp.FR-008.We believe this work could facilitate further development of Streptomyces sp.FR-008 for use in biotechnological applications. | Qian Liu Liping Xiao Yuanjie Zhou Kunhua Deng Gaoyi Tan Yichao Han Xinhua Liu Zixin Deng Tiangang Liu | 2016 | Synthetic and Systems Biotechnology2016，1，3： | 2 |
| 19 | High proportion strontium-doped micro-arc oxidation coatings enhance early osseointegration of titanium in osteoporosis by anti-oxidative stress pathway显示文摘The excessive accumulation of reactive oxygen species(ROS)under osteoporosis precipitates a microenvironment with high levels of oxidative stress(OS).This could significantly interfere with the bioactivity of conventional titanium implants,impeding their early osseointegration with bone.We have prepared a series of strontium(Sr)-doped titanium implants via micro-arc oxidation(MAO)to verify their efficacy and differences in osteoinduction capabilities under normal and osteoporotic(high OS levels)conditions.Apart from the chemical composition,all groups exhibited similar physicochemical properties(morphology,roughness,crystal structure,and wettability).Among the groups,the low Sr group(Sr25%)was more conducive to osteogenesis under normal conditions.In contrast,by increasing the catalase(CAT)/superoxide dismutase(SOD)activity and decreasing ROS levels,the high Sr-doped samples(Sr75% and Sr100%)were superior to Sr25% in inducing osteogenic differentiation of MC3T3-E1 cells and the M2 phenotype polarization of RAW264.7 cells,thus enhancing early osseointegration.Furthermore,the results of both in vitro cell co-culture and in vivo studies also showed that the high Sr-doped samples(especially Sr100%)had positive effects on osteoimmunomodulation under the OS microenvironment.Ultimately,the collated findings indicated that the high proportion Sr-doped MAO coatings were more favorable for osteoporosis patients in implant restorations. | Xinkun Shen Kai Fang Kendrick Hii Ru Yie Zixin Zhou Yiding Shen Shuyi Wu Yue Zhu Zhennan Deng Pingping Ma Jianfeng Ma Jinsong Liu | 2022 | Bioactive Materials2022，7，4： | 2 |
| 20 | Increasing the heterologous production of spinosad in Streptomyces albus J1074 by regulating biosynthesis of its polyketide skeleton显示文摘Spinosyns are natural broad-spectrum biological insecticides with a double glycosylated polyketide structure that are produced by aerobic fermentation of the actinomycete,Saccharopolyspora spinosa.However,their large-scale overproduction is hindered by poorly understood bottlenecks in optimizing the original strain,and poor adaptability of the heterologous strain to the production of spinosyn.In this study,we genetically engineered heterologous spinosyn-producer Streptomyces albus J1074 and optimized the fermentation to improve the production of spinosad(spinosyn A and spinosyn D)based on our previous work.We systematically investigated the result of overexpressing polyketide synthase genes(spnA,B,C,D,E)using a constitutive promoter on the spinosad titer in S.albus J1074.The supply of polyketide synthase precursors was then increased to further improve spinosad production.Finally,increasing or replacing the carbon source of the culture medium resulted in a final spinosad titer of~70 mg/L,which is the highest titer of spinosad achieved in heterologous Streptomyces species.This research provides useful strategies for efficient heterologous production of natural products. | Ziheng An Hui Tao Yong Wang Bingqing Xia Yang Zou Shuai Fu Fang Fang Xiao Sun Renqiong Huang Yao Xia Zixin Deng Ran Liu Tiangang Liu | 2021 | Synthetic and Systems Biotechnology2021，6，4： | 1 |
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