|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Improvement of oxytetracycline production mediated via cooperation of resistance genes in Streptomyces rimosus显示文摘Increasing the self-resistance levels of Streptomyces is an effective strategy to improve the production of antibiotics.To increase the oxytetracycline(OTC) production in Streptomyces rimosus,we investigated the cooperative effect of three co-overexpressing OTC resistance genes:one gene encodes a ribosomal protection protein(otrA) and the other two express efflux proteins(otrB and otrC).Results indicated that combinational overexpression of otrA,otrB,and otrC(MKABC) exerted a synergetic effect.OTC production increased by 179%in the recombinant strain compared with that of the wild-type strain M4018.The resistance level to OTC was increased by approximately two-fold relative to the parental strain,thereby indicating that applying the cooperative effect of self-resistance genes is useful to improve OTC production.Furthermore,the previously identified cluster-situated activator OtcR was overexpressed in MKABC in constructing the recombinant strain MKRABC;such strain can produce OTC of approximately7.49 g L^((-1)),which represents an increase of 19%in comparison with that of the OtcR-overexpressing strain alone.Our work showed that the cooperative overexpression of self-resistance genes is a promising strategy to enhance the antibiotics production in Streptomyces. | Shouliang Yin Xuefeng Wang Mingxin Shi Fang Yuan Huizhuan Wang Xiaole Jia Fang Yuan Jinliang Sun Tiejun Liu Keqian Yang Yuxiu Zhang Keqiang Fan Zilong Li | 2017 | Science China(Life Sciences)2017，60，9： | 10 |
| 2 | Regulatory perspective of antibiotic biosynthesis in Streptomyces显示文摘Streptomycetes are Gram-positive bacteria with high GC DNA content. They produce the most abundant secondary metabolites including over two-thirds of the clinically used antibiotics of natural origin (Barka et al., 2016), for example,the important broad-spectrum antimicrobials oxytetracycline(OTC) and chlortetracycline, which are the tetracycline antibiotics。 | Hanzhi Yin Weishan Wang Keqiang Fan Zilong Li | 2019 | Science China(Life Sciences)2019，62，5： | 3 |
| 3 | Neural-Fuzzy-Based Adaptive Sliding Mode Automatic Steering Control of Vision-based Unmanned Electric Vehicles显示文摘This paper presents a novel neural-fuzzy-based adaptive sliding mode automatic steering control strategy to improve the driving performance of vision-based unmanned electric vehicles with time-varying and uncertain parameters.Primarily,the kinematic and dynamic models which accurately express the steering behaviors of vehicles are constructed,and in which the relationship between the look-ahead time and vehicle velocity is revealed.Then,in order to overcome the external disturbances,parametric uncertainties and time-varying features of vehicles,a neural-fuzzy-based adaptive sliding mode automatic steering controller is proposed to supervise the lateral dynamic behavior of unmanned electric vehicles,which includes an equivalent control law and an adaptive variable structure control law.In this novel automatic steering control system of vehicles,a neural network system is utilized for approximating the switching control gain of variable structure control law,and a fuzzy inference system is presented to adjust the thickness of boundary layer in real-time.The stability of closed-loop neural-fuzzy-based adaptive sliding mode automatic steering control system is proven using the Lyapunov theory.Finally,the results illustrate that the presented control scheme has the excellent properties in term of error convergence and robustness. | Jinghua Guo Keqiang Li Jingjing Fan Yugong Luo Jingyao Wang | 2021 | Chinese Journal of Mechanical Engineering2021，34，5： | 2 |
| 4 | Molecular and Clinical Characterization of a Novel SCN5A Mutation Associated With Atrioventricular Block and Dilated Cardiomyopathy显示文摘 | Junbo Ge Aijun Sun Vesa Paajanen Shijun Wang Chunxi Su Zhiyin Yang Ying Li Shaochun Wang Jianguo Jia Keqiang Wang Yunzeng Zou Lizhi Gao Kun Wang Zheng Fan | 2008 | Circulation: Arrhythmia and Electrophysiology2008，，2： | 1 |
| 5 | The N - terminal Octapeptide Acts as a Dimerization Inhibitor of SARS Coronavirus 3-C-like Proteinase 显示文摘 | Ping Wei Keqiang Fan Hao Chen eta/ | 2006 | Biochemical and Biophysical Research Communications2006，339，3： | 1 |
| 6 | Molecular and Clinical Characterization of a Novel SCN5A Mutation Associated With Atrioventricular Block and Dilated Cardiomyopathy显示文摘 | Junbo Ge Aijun Sun Vesa Paajanen Shijun Wang Chunxi Su Zhiyin Yang Ying Li Shaochun Wang Jianguo Jia Keqiang Wang Yunzeng Zou Lizhi Gao Kun Wang Zheng Fan | 2008 | Circulation: Arrhythmia and Electrophysiology2008，，2： | 1 |
| 7 | The functional differentiation of the post-PKS tailoring oxygenases contributed to the chemical diversities of atypical angucyclines显示文摘Angucyclines are one of the largest families of aromatic polyketides with various chemical structures and bioactivities.Decades of studies have made it easy for us to depict the picture of their early biosynthetic pathways.Two families of oxygenases,the FAD-dependent oxygenases and the ring opening oxygenases,contribute to the formation of some unique skeletons of atypical angucyclines.The FAD-dependent oxygenases involved in the biosynthetic gene clusters of typical angucyclines catalyze two hydroxylation reactions at C-12 and C-12b of prejadomycin,while their homolog JadH in jadomycin gene cluster catalyze the C-12 hydroxylation and 4a,12b-dehydration reactions of prejadomycin,which leads to the production of dehydrorabelomycin,a common intermediate during the biosynthesis of atypical angucyclines.Ring opening oxygenases of a unique family of oxygenases catalyze the oxidative CeC bond cleavage reaction of dehydrorabelomycin,followed by different rearrangement reactions,resulting in the formation of the various chemical skeletons of atypical angucyclines.These results suggested that the functional differentiation of these oxygenases could apparently enrich the sources of aromatic polyketides with greater structure diversities. | Keqiang Fan Qian Zhang | 2018 | Synthetic and Systems Biotechnology2018，3，4： | 1 |
| 8 | Development of a pyrF-based counterselectable system for targeted gene deletion in Streptomyces rimosus显示文摘Streptomyces produces many valuable and important biomolecules with clinical and pharmaceutical applications.The development of simple and highly efficient gene editing tools for genetic modification of Streptomyces is highly desirable.In this study,we developed a screening system for targeted gene knockout using a uracil auxotrophic host(ΔpyrF)resistant to the highly toxic uracil analog of 5-fluoroorotic acid(5-FOA)converted by PyrF,and a non-replicative vector pKC1132-pyrF carrying the complemented pyrF gene coding for orotidine-5'-phosphate decarboxylase.The pyrF gene acts as a positive selection and counterselection marker for recombinants during genetic modifications.Single-crossover homologous integration mutants were selected on minimal medium without uracil by reintroducing pyrF along with pKC1132-pyrF into the genome of the mutantΔpyrF at the targeted locus.Double-crossover recombinants were generated,from which the pyrF gene,plasmid backbone,and targeted gene were excised through homologous recombination exchange.These recombinants were rapidly screened by the counterselection agent,5-FOA.We demonstrated the feasibility and advantage of using this pyrF-based screening system through deleting the otcR gene,which encodes the cluster-situated regulator that directly activates oxytetracycline biosynthesis in Streptomyces rimosus M4018.This system provides a new genetic tool for investigating the genetic characteristics of Streptomyces species. | Yiying YANG Qingqing SUN Yang LIU Hanzhi YIN Wenping YANG Yang WANG Ying LIU Yuxian LI Shen PANG Wenxi LIU Qian ZHANG Fang YUAN Shiwen QIU Jiong LI XuefengWANG Keqiang FAN Weishan WANG Zilong LI Shouliang YIN | 2021 | Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2021，22，5： | 0 |
| 9 | Tetracycline natural products:discovery,biosynthesis and engineering显示文摘Tetracycline(TC)natural products possess a variety of remarkable bioactivities and diverse structures.They are an important and fertile source for developing novel drugs.As one of the most successful drug families,TC antibiotics have been in clinical use for over seven decades,and continue to make an important contribution to human health nowadays.To date,studies on TC natural products and their biosynthesis have revealed numerous novel biochemical mechanisms and regulatory elements,which facilitates the rational metabolic engineering studies for generating novel bioactive TC analogs and inspires the development of new synthetic biology tools.In this review,we provide a comprehensive overview on the discovery,biosynthesis,and engineering of the existing TC natural products.These analyses will be of great value for the discovery,design and development of novel TC drugs in the future. | WANG Haiyan WANG Ljun FAN Keqiang PAN Guohui | 2022 | Chinese Journal of Natural Medicines2022，20，10： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员