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Journal of Integrative Agriculture 2023年第1期22卷 320-324页

作者： WANG Wen-jing WANG Yi-fu JIN Ya-jie SONG Wu-qiang LIN Jia-meng ZHANG Yan TONG Xin-ru TU Jian LI Rui-chao LI Tao Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research Institute of Pharmacy and PharmacologyUniversity of South ChinaHengyang 421001P.R.China Shanghai Veterinary Research Institute Chinese Academy of Agricultural SciencesShanghai 200241P.R.China Guilin Medical University Guilin 541199P.R.China Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses College of Veterinary MedicineYangzhou UniversityYangzhou 225009P.R.China

An extensively drug-resistant(XDR)escherichia coli strain 258E was isolated from an anal swab sample of a chicken farm of Anhui province in *** analyses indicated that the strain 258E harbors an incompatibility group N(IncN)plasmid pEC258-3,which co-produces bla_(CTX-M-3),bla_(KPC-2),bla_(TEM-1B),qnrS1,aac(6')-Ib-cr,dfrA14,arr-3,and aac(6')-*** genome arrangement analyses indicated that pEC258-3 is highly homologous with pCRKP-1-KPC discovered in Klebsiella pneumoniae from a ***,conjugation experiments proved that plasmid pEC258-3 can be transferred horizontally and may pose a significant potential threat in animals,community and hospital settings.

关键词： bla_(CTX-M-3) bla_(KPC-2) bla_(TEM-1B) IncN plasmid escherichia coli

Preparation of the Ag_2O_2-PbO_2 Modified Electrode and Its Application towards escherichia coli Fast Counting in Water

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Chinese Chemical Letters 2005年第5期16卷 635-638页

作者： JingGU WenZHANG YuFengYANG LeiZHENG ZiRongWU LiTongJIN DepartmentofChemistryEastChinaNormalUniversity Shanghai2000622 DepartmentofBiology EastChinaNormalUniversityShanghai200062

A novel nano crystalline Ag2O2-PbO2 film chemically modified electrode (CME) was prepared and the CME was characterized by X-ray diffractometer (XRD) and atomic force microscope (AFM). By chronoamperometry, the nano Ag2O2-PbO2 CME was used as bioelectro- chemical sensor to determine the population of escherichia coli (E. coli) in water. Compared with conventional methods, it is found that the technique we used is fast and convenient in counting E. coli.

关键词： Ag2O2-PbO2 modified platinum electrode escherichia coli fast counting.

Purification and application of C-terminally truncated hepatitis C virus El proteins expressed in escherichia coli

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World Journal of Gastroenterology 2005年第4期11卷 503-507页

作者： JingLiu Li-XinZhu Yu-YingKong Guang-DiLi YuanWang StateKeyLaboratoryofMolecularBiology InstituteofBiochemistryandCellBiologyShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesShanghai200031China

AIM: To explore the possibility of expressing hepatitis C virus (HCV) envelope protein 1 (E1) in escherichia coli(E, coli) and to test the purified recombinant E1 proteins for clinical and research applications. METHODS: C-terminally truncated E1 fragments were expressed in E, coli as hexa-histidine-tagged fusion proteins. The expression products were purified under denaturing conditions using immobilized-metal affinity chrbmatography. Purified E1 proteins were used to immunize rabbits. Rabbit anti-sera thus obtained were reacted with both E. coli- and mammalian cell-expressed E1 glycoproteins as detected by Western blot. RESULTS: Full-length E1 protein proved difficult to express in E. coli, C-terminally truncated E1 was successfully expressed in E. coli as hexa-histidine-tagged recombinant fusion protein and was purified under denaturing conditions on Ni2+-NTA agarose. Rabbit anti-sera raised against purified recombinant E1 specifically reacted with mammalian cell-expressed E1 giycoproteins in Western blot. Furthermore, E. coli-derived E1 protein was able to detect animal antibodies elicited by E1-based DNA immunization. CONCLUSION: These results demonstrate that the prokaryotically expressed E1 proteins share identical epitopes with eukaryotically expressed E1 glycoprotein. The E coli-derived E1 proteins and corresponding antisera can become useful tools in anti-HCV vaccine research.

关键词： HCV envelope protein 1 Recombinant Fusion Proteins escherichia coli

In vitro biofilm formation in ESBL producing escherichia coli isolates from cage birds

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Asian Pacific Journal of Tropical Medicine 2016年第11期9卷 1047-1052页

作者： Ebru Sebnem Yilmaz Nur Ceyhan Guvensen Mustafa Kemal University Faculty of Art and SciencesBiology Department Mugla Suki Kocman University Faculty of SciencesBiology Department

Objective:To determine biofilm and hydrophobicity formation ratios in extended spectrum beta lactamases(ESBL) synthesizing escherichia coli isolates which were isolated from feces samples of 150 cage bird species randomly taken from pet shops in Hatay province,***:In vitro biofilm production of 4 ESBL positive isolates were performed by Congo Red Agar(CRA),Standard Tube(ST) and Microtitre Plate(MP) methods while their hydrophobicity were examined by bacterial adhesion to hydrocarbon(BATH) ***:In the examined isolates,while biofilm production was found to be negative by CRA method,highest biofilm producing strain,among 4 bacteria was determined to be A42 by ST and MP *** Scanning Electron Microscopy(SEM) also displayed these confirmed *** hydrophobicity values of strains were determined to be between 22.45%and 26.42%.Conclusions:As a result,biofilm formation in cage bird feces originated ESBL positive escherichia coli isolates was performed for the first time in *** order to present the relation between pathogenicity and biofilm production in animal originated ESBL positive isolates,further studies are required.

关键词： escherichia coli Extended spectrum beta lactamases Biofilm formation Hydrophobicity Cage birds

Preclinical and clinical evidence of the association of colibactinproducing escherichia coli with anxiety and depression in colon cancer

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World Journal of Gastroenterology 2024年第21期30卷 2817-2826页

作者： Fabien Rondepierre Maëva Meynier Johan Gagniere Vincent Deneuvy Anissa Deneuvy Gwenaelle Roche Elodie Baudu Bruno Pereira Richard Bonnet Nicolas Barnich Frédéric Antonio Carvalho Denis Pezet Mathilde Bonnet Isabelle Jalenques Service de Psychiatrie de l’Adulte A et Psychologie Médicale CHU Clermont-FerrandClermont-Ferrand 63000France M2iSH UMR 1071INSERMUniversity of Clermont AuvergneINRAE USC 1382Clermont-Ferrand 63001France NeuroDol UMR 1107INSERMUniversity of Clermont AuvergneClermont-Ferrand 63001France Department of Digestive Surgery CHU de Clermont-FerrandClermont-Ferrand 63001France Biostatistics Unit Department of Clinical Research and InnovationCHU Clermont-FerrandClermont-Ferrand 63000France Department of Bacteriology CHU de Clermont-FerrandClermont-Ferrand 63001France UniversitéClermont Auvergne INPCNRSClermont Auvergne Institut PascalClermont-Ferrand 63000France

BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly *** gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin-producing escherichia coli(CoPEC).AIM To evaluate the association between CoPEC prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical *** Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric *** were compared according to the CoPEC *** parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC *** behavior was assessed using the Elevated Plus Maze test,the Forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without CoPEC *** result was confirmed in C57BL6/J wildtype mice and in a CRC susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a CoPEC *** This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.

关键词： Colorectal cancer colibactin escherichia coli colibactin-producing escherichia coli Inflammation Anxiety Depression Behavior

Engineering escherichia coli to improve tryptophan production via genetic manipulation of precursor and cofactor pathways

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Synthetic and Systems Biotechnology 2020年第3期5卷 200-205页

作者： Zhu Li Dongqin Ding Huiying Wang Linxia Liu Huan Fang Tao Chen Dawei Zhang Key Laboratory of Systems Bioengineering of the Ministry of Education School of Chemical Engineering and TechnologySynBio Research PlatformCollaborative Innovation Centre of Chemical Science and EngineeringTianjin UniversityTianjin300072China Key Laboratory of Systems Microbial Biotechnology Chinese Academy of SciencesTianjin300308China Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin300308China University of Chinese Academy of Sciences Beijing100049China

Optimizing the supply of biosynthetic precursors and cofactors is usually an effective metabolic strategy to improve the production of target ***,the combination of optimizing precursor synthesis and balancing cofactor metabolism was adopted to improve tryptophan production in escherichia ***,glutamine synthesis was improved by expressing heterologous glutamine synthetase from Bacillus subtilis and Bacillus megaterium in the engineered escherichia coli strain KW001,resulting in the best candidate strain *** icd and gdhA were overexpressed in TS-1,which led to the accumulation of 1.060 g/L ***,one more copy of prs was introduced on the chromosome to increase the flux of 5-phospho-α-D-ribose 1-diphosphate followed by the expression of mutated serA and thrA to increase the precursor supply of serine,resulting in the accumulation of 1.380 g/L ***,to maintain cofactor balance,sthA and pntAB,encoding transhydrogenase,were *** sufficient amounts of precursors and balanced cofactors,the engineered strain could produce 1.710 g/L tryptophan after 48 h of shake-flask fermentation,which was 2.76-times higher than the titer of the parent *** together,our results demonstrate that the combination of optimizing precursor supply and regulating cofactor metabolism is an effective approach for high-level production of *** strategies could be applied to the production of other amino acids or related derivatives.

关键词： escherichia coli Tryptophan Metabolic precursors Cofactor supply

Chemical analysis and in vitro antimicrobial effects and mechanism of action of Trachyspermum copticum essential oil against escherichia coli

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Asian Pacific Journal of Tropical Medicine 2017年第7期10卷 726-732页

作者： Wei Huang Jian-Qing Wang Hai-Yan Song Qian Zhang Guang-Fa Liu Tianjin University of Science & Technology China Packaging Research&Test Center

Objective: To find a natural plant essential oil (EO) with excellent antimicrobial effect on food-borne bacteria and to explore the mechanism of its antimicrobial function against escherichia colt (E. cal). Methods: The antimicrobial activity of seven EOs against Gramnegative E. coli ATCC 8739 and Gram-positive Staphylococcus aureus ATCC 6538 was investigated using agar disk diffusion method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each EO was determined using the broth dilution method. The chemical composition of the Trachyspermum copticum (T. copticum) EO was analyzed using gas chromatography mass spectrometry (GC/MS). In order to explore the mechanism of the antimicrobial action, 1 MIC and 2 MIC of T. copticum. EO was added to a suspension of E. coli, the growth curve and the scanning electron microscopy (SEM) analysis of E. coli, and the release of cell constituents and protein and potassium ions from the bacterial cell were measured. Results: The T. optician EO had the best antimicrobial activity against the test bacteria, and 10 compounds accounting for 94.57% of the total oil were identified, with the major components being thymol (46.22%), p-cymene (19.03%), and y-terpinene (22.41%). The addition of I MIC T. copticum. EO significantly inhibited the growth of E. coli and increased the release of cell constituents and protein and potassium ions from the bacterial cells. Scanning electron micrographs showed that T. copticum EO caused most of the E. co/i cell membranes to collapse and rupture, leading to cell death. Conclusions: These results indicate that T. copticum EO is a good natural antimicrobial agent for food-borne pathogens.

关键词： Essential oil Trachyspermum copticum Antimicrobial activity GC/MS escherichia coli Mechanism

Rotula aquatica Lour. inhibits growth and biofilm formation of clinically isolated uropathogenic escherichia coli

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Asian Pacific Journal of Tropical Biomedicine 2020年第12期10卷 547-554页

作者： A.Vysakh Sebastian Jose Midhun Ninan Jisha Kuriakose Jayesh V.Vijeesh Mathew Jyothis MS Latha School of Biosciences Mahatma Gandhi UniversityPriyadarshini HillsKottayamKeralaIndia

Objective:To evaluate the anti-bacterial and anti-biofilm activity of ethyl acetate fraction of Rotula aquatica Lour.(EFRA)against clinically isolated uropathogenic escherichia ***:In vitro antibacterial and anti-biofilm studies were *** antimicrobial activity of EFRA was assayed by the well diffusion *** minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of the active fraction were determined by Resazurin *** time-kill kinetic assay,acridine orange-ethidium bromide staining,propidium iodide uptake assay,and scanning electron microscopic(SEM)analysis were done to evaluate the efficacy of EFRA in killing uropathogenic escherichia *** anti-biofilm activity was determined by 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2 H-tetrazolium-bromide(MTT)assay and specific biofilm formation ***:The well diffusion assay of EFRA showed a very clear zone of inhibition against escherichia coli *** MIC and MBC of EFRA were 2.5 mg/m L and 5 mg/m L,*** time-kill kinetic assay,fluorescence microscopic analysis,propidium iodide uptake assay,and SEM analysis displayed the effect of EFRA in killing the *** MTT assay and specific biofilm formation assay showed that EFRA prevented the formation of ***:The results of the present study confirm that EFRA could prevent bacterial growth and inhibit its biofilm formation.

关键词： Rotula aquatica escherichia coli Urinary tract infections Anti-bacterial activity

Improvement of lycopene biosynthesis in waaC and waaF mutants of escherichia coli by integrant expression of crtEBI gene and deletion of aceE and gdhA

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Systems Microbiology and Biomanufacturing 2023年第4期3卷 739-749页

作者： Xiaoqing Hu Mao Cui Xiaoyuan Wang State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China International Joint Laboratory on Food Safety Jiangnan UniversityWuxi 214122China

As a bright red carotenoid pigment found in tomatoes and other red fruits,lycopene was efficiently produced by escherichia coli transformed with the genes involving in lycopene *** previous work showed that ***ΔwaaC andΔwaaF with higher permeability of outer membrane were better chassis for lycopene ***,further work needed to improve lycopene synthesis in the aforementioned *** the current study,the exogenous crtEBI genes from *** 14067 were first integrated into the chromosome ofΔwaaC andΔ*** toΔwaaC/pWSK29-crtEBI andΔwaaF/pWSK29-crtEBI(4.19 and 4.20 mg/g lycopene respectively),ΔwaaC lacZ::crtEBI(CWC01)andΔwaaF lacZ::crtEBI(CWF01)produced higher lycopene levels at 16.14 mg/g and 15.81 mg/g,***,the individual and combinational deletion of aceE and gdhA was conducted in CWC01 and CWF01,*** double knock-out strains CWC04 and CWF04 showed the improved yield at 19.65 mg/g and 22.24 mg/g,***,the four genes involving in MEP pathway(dxs,dxr,ispA and idi)were further *** highest lycopene yield was achieved at 25.82 mg/g by CWF04/pACYC184-dxs^(E289G)-dxr^(K37N,K217N)-*** current study showed that ***ΔwaaC andΔwaaF were optimal chassis for ambitious metabolic modification to produce lycopene.

关键词： Lycopene escherichia coli waaC waaF

Total Alkaloids from Sophora Alopecuroides *** Susceptibility of Extended-Spectrum β-Lactamases Producing escherichia coli Isolates to Cefotaxime and Ceftazidime

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Chinese Journal of Integrative Medicine 2013年第12期19卷 945-952页

作者：周学章贾芳刘晓明杨聪赵莉王玉炯 Key Laboratory of the Ministry of Education for the Conservation and Utilization of Special Biological Resources of Western China College of Life ScienceNingxia University

Objective： To evaluate the antimicrobial activity of total alkaloids extracted from Sophorea alopecuroides L. （TASA） against clinical isolated extended-spectrum beta-lactamases （ESBLs） producing escherichia coil （E.. coil） strains. Methods： The antibacterial activity of TASA either itself or in combination with cefotaxime （CTX） or ceftazidime （CAZ） was investigated by using the microbroth dilution method and phenotypic confirmatory disk diffusion test against three clinical isolated ESBLs-producing E. coil strains; the interactions of TASA and C＇I＇X or CAZ were ascertained by evaluating the fractional inhibitory concentration index （FICI）. Results： The antibacterial activity of either TASA itself or in combination with C＇IX or CAZ was found. The minimum inhibitory concentration （MICs） of TASA against the ESBLs producing isolates was 12.5 mg/mL. In the combinations with a sub-inhibitory concentration of TASA, a synergistic effect on CTX and CAZ against the ESBLs producing isolates was observed. Similarly, the isolates exposed to lower dose of TASA yielded an increased susceptibility to CTX and CAZ by 8-16 folds determined by microdilution assay. Moreover, enzymatic detection of ESBLs demonstrated that TASA induced reversal resistance to CTX and CAZ partially by a mechanism of inhibition of ESBLs activity in these isolates. Additionally, in the tested isolates following the exposure of TASA, molecular analysis verified the SHV-type beta-lactamase encoding ESBL gene in these isolates, and no mutation was introduced into the ESBL gene. Conclusions： These results suggest that TASA could be used as a source of natural compound with pharmacological activity of reversal resistance to antimicrobial agent. These findings also indicated that the application of the TASA in combination with antibiotics might prove useful in the control and treatment of infectious diseases caused by the ESBLs producing enterobacteriaceae.

关键词： total alkaloids Sophorea alopecuroides L. extended spectrum β-1actamases antibiotic resistance escherichia coli