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Advances and mechanisms of traditional Chinese medicine and its active ingredients against antibiotic-resistant Escherichia coli infections 被引量:1
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作者 Shuo Yang Ping Su +2 位作者 Lu Li Shuang Liu Yi Wang 《Journal of Pharmaceutical Analysis》 2025年第2期375-388,共14页
In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challeng... In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challenge to this approach.In 2022,Escherichia coli,a Gram-negative bacterium renowned for its widespread pathogenicity and high virulence,emerged as the predominant pathogenic bacterium in China.The rapid emergence of antibiotic-resistant E.coli strains has rendered antibiotics insufficient to fight E.coli infections.Traditional Chinese medicine(TCM)has made remarkable contributions to the health of Chinese people for thousands of years,and its significant therapeutic effects have been proven in clinical practice.In this paper,we provide a comprehensive review of the advances and mechanisms of TCM and its active ingredients against antibiotic-resistant E.coli infections.First of all,this review introduces the classification,antibiotic resistance characteristics and mechanisms of E.coli.Then,the TCM formulas and extracts are listed along with their active ingredients against E.coli,including extraction solution,minimum inhibitory concentration(MIC),and the antibacterial mechanisms.In addition,there is growing evidence supporting the synergistic therapeutic strategy of combining TCM with antibiotics for the treatment of antibiotic-resistant E.coli infections,and we provide a summary of this evidence and its underlying mechanisms.In conclusion,we present a comprehensive review of TCM and highlight its potential and advantages in the prevention and treatment of E.coli infections.We hold the opinion that TCM will play an important role in global health,pharmaceutical development,and livestock farming in the future. 展开更多
关键词 Escherichia coli ANTIBIOTIC-RESISTANCE Traditional Chinese medicine Active ingredients Antibacterial mechanism
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Dietary supplementation of blend of organic acids and monoglycerides alleviated diarrhea and systemic inflammation of weaned pigs experimentally infected with enterotoxigenic Escherichia coli F18 被引量:1
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作者 Sangwoo Park Shuhan Sun +3 位作者 Supatirada Wongchanla Ying Chen Xunde Li Yanhong Liu 《Journal of Animal Science and Biotechnology》 2025年第3期1255-1268,共14页
Background The emergence of antibiotic resistant microorganisms associated with conventional swine production practices has increased interest in acid-based compounds having antimicrobial properties and other biologic... Background The emergence of antibiotic resistant microorganisms associated with conventional swine production practices has increased interest in acid-based compounds having antimicrobial properties and other biological functions as nutritional interventions.Despite the interest in organic acids and monoglycerides,few studies have examined the effects of the combination of these acid-based additives in weaned pigs under disease challenge conditions.Therefore,this study aimed to investigate the effects of dietary supplementation with blend of organic acids and/or medium-chain fatty acid monoglycerides on intestinal health and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli(ETEC)F18 at 4-week of age.Results Dietary supplementation of organic acids,monoglycerides,or both organic acids and monoglycerides(combination)reduced(P<0.05)the diarrhea frequency of ETEC F18-infected pigs throughout the experimental period(d−7 to 21 post-inoculation).This is consistent with the reduced(P<0.05)proportion ofβ-hemolytic coliforms in feces observed for the organic acid and combination treatments on d 10 post-inoculation.Supplementation of organic acids,monoglycerides,or combination also reduced(P<0.05)bacterial translocation in mesenteric lymph nodes on d 21 post-inoculation.Pigs fed with monoglycerides or combination had lower(P<0.05)white blood cells on d 5 post-inoculation,and pigs fed the combination also had lower(P<0.05)lymphocytes than pigs in control group.Monoglyceride supplementation increased(P<0.05)white blood cells and neutrophils compared with control group on d 14 post-inoculation.However,supplementation with organic acid blend,monoglyceride blend,or combination did not affect growth performance in this experiment.Conclusions Supplementation with monoglycerides or organic acids alone or in combination improves the detrimental effects of ETEC F18 infection in weaned pigs,as indicated by reduced diarrhea,fecal shedding ofβ-hemolytic coliforms,and bacterial translocation,and thus enhancing disease resistance.Monoglycerides reduced the inflammatory response during peak infection,but their immunomodulatory and possible synergistic effects with organic acids need to be further investigated. 展开更多
关键词 Acidifiers Antimicrobial agents DIARRHEA Enterotoxigenic Escherichia coli MONOGLYCERIDES Systemic immunity Weaned pigs
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Escherichia coli O157:H7的表面增强拉曼光谱检测方法建立
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作者 王盼雪 李岑 +2 位作者 李香 刘莹 李国梁 《食品与生物技术学报》 北大核心 2025年第6期97-105,共9页
【目的】提高大肠杆菌(Escherichia coli,E.coli)O157:H7检测的特异性和灵敏度。【方法】基于磁分离和信号放大策略,结合表面增强拉曼光谱(SERS)技术建立了一种特异性好、灵敏度高的E.coli O157:H7检测方法。以适配体为识别元件,联合磁... 【目的】提高大肠杆菌(Escherichia coli,E.coli)O157:H7检测的特异性和灵敏度。【方法】基于磁分离和信号放大策略,结合表面增强拉曼光谱(SERS)技术建立了一种特异性好、灵敏度高的E.coli O157:H7检测方法。以适配体为识别元件,联合磁珠和聚苯乙烯(PS)微球,分别构建分离探针MB@Apt和信号放大型拉曼标签4-MBN@PS@Apt。【结果】当E.coli O157:H7存在时,MB@Apt、4-MBN@PS@Apt与E.coli O157:H7可形成MB@Apt/E.coli O157:H7/4-MBN@PS@Apt“三明治”结构复合物,该复合物可借助外源磁场实现快速分离和富集;加入四氢呋喃(THF)后,拉曼标签上负载的低生物背景拉曼报告物4-MBN可被快速释放。4-MBN在1073.9 cm^(-1)处的相对拉曼强度与E.coli O157:H7浓度的对数值在1×10^(3)~1×10^(8) CFU/mL的线性关系良好,决定系数(R^(2))为0.98。该方法对E.coli O157:H7的检测限(LOD)为312 CFU/mL,在自来水和牛奶样本中的检测回收率为61.87%~135.55%,相对标准偏差(RSD)为0.27%~5.28%。【结论】该方法对E.coli O157:H7的检测灵敏度较高,为食源性致病菌的快速检测提供了新思路。 展开更多
关键词 Escherichia coli O157:H7 快速检测 表面增强拉曼光谱 聚苯乙烯微球 低生物背景
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Genome-scale metabolic network model-guided genetic modification of Escherichia coli for pyruvate accumulation
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作者 LI Xuefei GUO Chaohao +4 位作者 TONG Wenyue YANG Sen LIU Xiaoyun LI Jingchen KANG Ming 《微生物学报》 北大核心 2025年第10期4374-4391,共18页
[Objective]To construct an Escherichia coli mutant strain that accumulates pyruvate by genetic modification guided by the genome-scale metabolic network model.[Methods]Using a genome-scale metabolic network model as a... [Objective]To construct an Escherichia coli mutant strain that accumulates pyruvate by genetic modification guided by the genome-scale metabolic network model.[Methods]Using a genome-scale metabolic network model as a guide,we simulated pyruvate production of E.coli,screened key genes in metabolic pathways,and developed gene editing procedures accordingly.We knocked out the acetate kinase gene ackA,phosphate acetyltransferase gene pta,alcohol dehydrogenase adhE,glycogen synthase gene glgA,glycogen phosphorylase gene glgP,phosphoribosyl pyrophosphate(PRPP)synthase gene prs,ribose 1,5-bisphosphate phosphokinase gene phnN,and transporter encoding gene proP.Furthermore,we knocked in the transporter encoding gene ompC,flavonoid toxin gene fldA,and D-serine ammonia lyase gene dsdA.[Results]A shake flask process with the genetically edited mutant strain MG1655-6-2 under anaerobic conditions produced pyruvate at a titer of 10.46 g/L and a yield of 0.69 g/g.Metabolomic analysis revealed a significant increase in the pyruvate level in the fermentation broth,accompanied by notable decreases in the levels of certain related metabolic byproducts.Through 5 L fed-batch fermentation and an adaptive laboratory evolution,the strain finally achieved a pyruvate titer of 45.86 g/L.[Conclusion]This study illustrated the efficacy of a gene editing strategy predicted by a genome-scale metabolic network model in enhancing pyruvate accumulation in E.coli under anaerobic conditions and provided novel insights for microbial metabolic engineering. 展开更多
关键词 Escherichia coli PYRUVATE genome-scale metabolic network model CRISPR-Cas9 adaptive laboratory evolution
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Metagenomics reveals an increased proportion of an Escherichia colidominated enterotype in elderly Chinese people
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作者 Jinyou LI Yue WU +10 位作者 Yichen YANG Lufang CHEN Caihong HE Shixian ZHOU Shunmei HUANG Xia ZHANG Yuming WANG Qifeng GUI Haifeng LU Qin ZHANG Yunmei YANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第5期477-492,共16页
Gut microbial communities are likely remodeled in tandem with accumulated physiological decline during aging,yet there is limited understanding of gut microbiome variation in advanced age.Here,we performed a metagenom... Gut microbial communities are likely remodeled in tandem with accumulated physiological decline during aging,yet there is limited understanding of gut microbiome variation in advanced age.Here,we performed a metagenomics-based enterotype analysis in a geographically homogeneous cohort of 367 enrolled Chinese individuals between the ages of 60 and 94 years,with the goal of characterizing the gut microbiome of elderly individuals and identifying factors linked to enterotype variations.In addition to two adult-like enterotypes dominated by Bacteroides(ET-Bacteroides)and Prevotella(ET-Prevotella),we identified a novel enterotype dominated by Escherichia(ET-Escherichia),whose prevalence increased in advanced age.Our data demonstrated that age explained more of the variance in the gut microbiome than previously identified factors such as type 2 diabetes mellitus(T2DM)or diet.We characterized the distinct taxonomic and functional profiles of ET-Escherichia,and found the strongest cohesion and highest robustness of the microbial co-occurrence network in this enterotype,as well as the lowest species diversity.In addition,we carried out a series of correlation analyses and co-abundance network analyses,which showed that several factors were likely linked to the overabundance of Escherichia members,including advanced age,vegetable intake,and fruit intake.Overall,our data revealed an enterotype variation characterized by Escherichia enrichment in the elderly population.Considering the different age distribution of each enterotype,these findings provide new insights into the changes that occur in the gut microbiome with age and highlight the importance of microbiome-based stratification of elderly individuals. 展开更多
关键词 Gut microbiome Aging Elderly population Escherichia-dominated enterotype Enterotype Escherichia coli
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Effects of monoglyceride blend on systemic and intestinal immune responses,and gut health of weaned pigs experimentally infected with a pathogenic Escherichia coli
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作者 Sangwoo Park Shuhan Sun +5 位作者 Lauren Kovanda Adebayo O.Sokale Adriana Barri Kwangwook Kim Xunde Li Yanhong Liu 《Journal of Animal Science and Biotechnology》 2025年第1期345-363,共19页
Background Monoglycerides have emerged as a promising alternative to conventional practices due to their biolog-ical activities,including antimicrobial properties.However,few studies have assessed the efficacy of mono... Background Monoglycerides have emerged as a promising alternative to conventional practices due to their biolog-ical activities,including antimicrobial properties.However,few studies have assessed the efficacy of monoglyceride blend on weaned pigs and their impacts on performance,immune response,and gut health using a disease chal-lenge model.Therefore,this study aimed to investigate the effects of dietary monoglycerides of short-and medium-chain fatty acids on the immunity and gut health of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli F18.Results Pigs supplemented with high-dose zinc oxide(ZNO)had greater(P<0.05)growth performance than other treatments,but no difference was observed in average daily feed intake between ZNO and monoglycerides groups during the post-challenge period.Pigs in ZNO and antibiotic groups had lower(P<0.05)severity of diarrhea than control,but the severity of diarrhea was not different between antibiotic and monoglycerides groups.Pigs fed with monoglycerides or ZNO had lower(P<0.05)serum haptoglobin on d 2 or 5 post-inoculation than control.Pigs in ZNO had greater(P<0.05)goblet cell numbers per villus,villus area and height,and villus height:crypt depth ratio(VH:CD)in duodenum on d 5 post-inoculation than pigs in other treatments.Pigs supplemented with monoglyc-erides,ZNO,or antibiotics had reduced(P<0.05)ileal crypt depth compared with control on d 5 post-inoculation,contributing to the increase(P=0.06)in VH:CD.Consistently,pigs in ZNO expressed the lowest(P<0.05)TNFa,IL6,IL10,IL12,IL1A,IL1B,and PTGS2 in ileal mucosa on d 5 post-inoculation,and no difference was observed in the expres-sion of those genes between ZNO and monoglycerides.Supplementation of ZNO and antibiotic had significant impacts on metabolic pathways in the serum compared with control,particularly on carbohydrate and amino acid metabolism,while limited impacts on serum metabolites were observed in monoglycerides group when compared with control.Conclusions The results suggest that supplementation of monoglyceride blend may enhance disease resist-ance of weaned pigs by alleviating the severity of diarrhea and mitigating intestinal and systemic inflammation,although the effectiveness may not be comparable to high-dose zinc oxide. 展开更多
关键词 DIARRHEA Enterotoxigenic Escherichia coli Gut health MONOGLYCERIDES Systemic immunity Weaned pigs
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Investigating the antibiofilm activity of Terebinthinae oleum 30C,200C,and 1M against urinary tract infections-causing Escherichia coli
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作者 Sibin Ramabhadran Anandavally Murugan Muthum Perumal Vel amrita Ganesan 《Infectious Diseases Research》 2025年第3期16-22,共7页
Background:Urinary tract infections(UTIs),primarily caused by uropathogenic Escherichia coli(UPEC),are a significant global health concern.The complications arise from antibiotic resistance and biofilm formation,which... Background:Urinary tract infections(UTIs),primarily caused by uropathogenic Escherichia coli(UPEC),are a significant global health concern.The complications arise from antibiotic resistance and biofilm formation,which reduce the effectiveness of conventional treatments.This study aims to evaluate the antibiofilm activity of the homeopathic medicine Terebinthinae oleum in potencies 30C,200C,and 1M against UTI-causing E.coli,and to compare its effectiveness with the standard antibiotic Gentamycin.Methods:An in-vitro biofilm model was employed.E.coli biofilms were cultivated in microtiter plates and treated with Terebinthinae oleum(30C,200C,1M)and Gentamycin.Biofilm biomass was assessed through crystal violet staining,and optical density(OD)was measured using an ELISA microplate reader.Results:Among the tested potencies,Terebinthinae oleum 30C showed the most prominent inhibitory activity on E.coli biofilms.The inhibition percentage was compared with Gentamycin as a control.Terebinthinae oleum 30C demonstrated 41.88%inhibition of biofilm biomass,while Gentamycin exhibited up to 78.98%inhibition.Higher potencies of Terebinthinae oleum(200C and 1M)showed reduced activity(30.15%and 24.81%,respectively).Conclusion:Terebinthinae oleum,especially at 30C potency,exhibits measurable antibiofilm activity against E.coli,although less effective than Gentamycin.These findings support its use as a complementary therapy in managing biofilm-associated UTIs,justifying further clinical and immunological research. 展开更多
关键词 urinary tract infection Escherichia coli Terebinthinae oleum biofilm HOMOEOPATHY GENTAMYCIN crystal violet antibiofilm activity
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The Role of the Quorum Sensing Signaling Pathway in Clinical Drug Resistance of Escherichia coli:A Review and Outlook
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作者 Chaolian Yang Bin Hu Chen Li 《Journal of Clinical and Nursing Research》 2025年第10期147-156,共10页
Quorum sensing(QS)represents a mechanism through which bacteria engage in communication via chemical signals,a phenomenon prevalent across diverse bacterial species.Recent investigations have elucidated that QS signal... Quorum sensing(QS)represents a mechanism through which bacteria engage in communication via chemical signals,a phenomenon prevalent across diverse bacterial species.Recent investigations have elucidated that QS signaling pathways are pivotal in governing bacterial physiological processes,collective behaviors,and the emergence of drug resistance.Escherichia coli(E.coli),a prominent pathogenic bacterium,is increasingly exhibiting severe drug resistance issues,posing substantial hurdles for clinical interventions.Presently,a burgeoning body of research is exploring the connection between QS signaling pathways and the drug resistance mechanisms in E.coli,unveiling the coordinating function of QS within bacterial communities and its influence on antibiotic resistance.Despite some research advancements,the precise mechanisms underlying the QS signaling pathway remain ambiguous,and its potential applications are somewhat constrained.This article endeavors to systematically review the research progress concerning the QS signaling pathway in the context of clinical drug resistance mechanisms in E.coli,delving into its potential clinical applications and future research avenues,with the aim of offering novel insights and strategies to counteract drug resistance. 展开更多
关键词 Antibiotic resistance BIOFILM Escherichia coli Quorum sensing QS inhibitors
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Effects of dietary Lactobacillus postbiotics and bacitracin on the modulation of mucosaassociated microbiota and pattern recognition receptors affecting immunocompetence of jejunal mucosa in pigs challenged with enterotoxigenic F18^(+)Escherichia coli
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作者 Marcos Elias Duarte Zixiao Deng Sung Woo Kim 《Journal of Animal Science and Biotechnology》 2025年第1期282-299,共18页
Background Enterotoxigenic Escherichia coli(E.coli)is a threat to humans and animals that causes intestinal dis-orders.Antimicrobial resistance has urged alternatives,including Lactobacillus postbiotics,to mitigate th... Background Enterotoxigenic Escherichia coli(E.coli)is a threat to humans and animals that causes intestinal dis-orders.Antimicrobial resistance has urged alternatives,including Lactobacillus postbiotics,to mitigate the effects of enterotoxigenic E.coli.Methods Forty-eight newly weaned pigs were allotted to NC:no challenge/no supplement;PC:F18^(+)E.coli chal-lenge/no supplement;ATB:F18^(+)E.coli challenge/bacitracin;and LPB:F18^(+)E.coli challenge/postbiotics and fed diets for 28 d.On d 7,pigs were orally inoculated withF18^(+)E.coli.At d 28,the mucosa-associated microbiota,immune and oxidative stress status,intestinal morphology,the gene expression of pattern recognition receptors(PRR),and intestinal barrier function were measured.Data were analyzed using the MIXED procedure in SAS 9.4.Results PC increased(P<0.05)Helicobacter mastomyrinus whereas reduced(P<0.05)Prevotella copri and P.ster-corea compared to NC.The LPB increased(P<0.05)P.stercorea and Dialister succinatiphilus compared with PC.The ATB increased(P<0.05)Propionibacterium acnes,Corynebacterium glutamicum,and Sphingomonas pseudosanguinis compared to PC.The PC tended to reduce(P=0.054)PGLYRP4 and increased(P<0.05)TLR4,CD14,MDA,and crypt cell proliferation compared with NC.The ATB reduced(P<0.05)NOD1 compared with PC.The LPB increased(P<0.05)PGLYRP4,and interferon-γand reduced(P<0.05)NOD1 compared with PC.The ATB and LPB reduced(P<0.05)TNF-αand MDA compared with PC.Conclusions TheF18^(+)E.coli challenge compromised intestinal health.Bacitracin increased beneficial bacteria show-ing a trend towards increasing the intestinal barrier function,possibly by reducing the expression of PRR genes.Lac-tobacillus postbiotics enhanced the immunocompetence of nursery pigs by increasing the expression of interferon-γand PGLYRP4,and by reducing TLR4,NOD1,and CD14. 展开更多
关键词 Escherichia coli IMMUNOCOMPETENCE Intestinal health Pattern recognition receptors PIGS
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Evaluation of antimicrobial resistance and virulence characteristics in Escherichia coli and Proteus mirabilis isolates from dead Crested Ibis embryos at the artificial breeding base
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作者 Gang Shu Lu Qu +9 位作者 Weiyi Yang Ziqin Lin Hanqian Dong Danqin Li Haiqiong Yang Wei Zhang Haohuan Li Funeng Xu Hualin Fu Juchun Lin 《Avian Research》 2025年第2期275-283,共9页
Bacterial infections of avian embryos can lead to an increase in embryo mortality,and the proliferation of antimicrobial-resistant bacteria aggravates the situation.A low hatching rate also poses a challenge to the po... Bacterial infections of avian embryos can lead to an increase in embryo mortality,and the proliferation of antimicrobial-resistant bacteria aggravates the situation.A low hatching rate also poses a challenge to the population of artificially bred Crested Ibises(Nipponia nippon).This study aims to determine the potential association between bacterial infection and the death of Crested Ibis embryos,and whether there is convergence between antimicrobial resistance and virulence in strain.In this study,13 Escherichia coli and 12 Proteus mirabilis isolates were recovered from dead Crested Ibis embryos.The pathogenicity examination confirmed the pathogenicity of all isolates,and multiple virulence genes detected by PCR-sequencing demonstrated the presence of irp2 and iuc D(100%),fim C and iss(92.31%)in E.coli,and uca A(58.33%)in P.mirabilis.Antimicrobial susceptibility test demonstrated that isolates were mainly resistant to amoxicillin(E.coli:76.92%,P.mirabilis:91.67%),cefazolin(E.coli:76.92%,P.mirabilis:91.67%),oxytetracycline(E.coli:92.31%,P.mirabilis:75.00%)and sulfamethoxazole-trimethoprim(E.coli:53.85%,P.mirabilis:33.33%),and more than 30%of isolates showed multidrug-resistance(MDR).Further analyses detected extended-spectrumβ-lactamase(ESBL)genes,of which blaTEM-1(E.coli:100%,P.mirabilis:100%)had the highest frequency,followed by the blaCTX-M-55(E.coli:92.31%,P.mirabilis:50%),blaCTX-M-14(E.coli:76.92%,P.mirabilis:33.33%),blaCTX-M-65(E.coli:15.38%,P.mirabilis:16.67%),and all isolates were negative for blaSHV and blaOXA.Pearson's correlation analysis showed a positive correlation between the presence ofβ-lactam resistance and ESBL genes,while mainly negative correlations were observed between the presence of ESBL genes and virulence genes.Furthermore,the conjugation experiment and PFGE revealed that the isolates were primarily polyclonal,and there was horizontal transfer of resistance or virulence genes by plasmids.Based on the results,E.coli and P.mirabilis were responsible for embryonic mortality of the ibises in this study.The co-presence and co-transfer of ESBL genes and virulence genes can pose a potential threat to the health of the Crested Ibis,and measures such as prudent use of antimicrobials,and constant surveillance of resistance and pathogenicity,must be implemented at the Crested Ibis breeding base. 展开更多
关键词 Dead embryo Escherichia coli Nipponia nippon Proteus mirabilis Resistance ESBL gene Virulence gene
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Comparative Analysis of Golden Gate and ClassicalCloning Techniques in E.coli:A Study in Molecular Cloning Efficiency
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作者 Ziyao Liu 《Asia Pacific Journal of Clinical Medical Research》 2025年第2期29-38,共10页
Molecular cloning remains a cornerstone technique in genetic engineering and synthetic biology.In this study,we conducted a systematic comparative analysis between the classical cloning method and the Golden Gate asse... Molecular cloning remains a cornerstone technique in genetic engineering and synthetic biology.In this study,we conducted a systematic comparative analysis between the classical cloning method and the Golden Gate assembly technique,utilizing Escherichia coli as the model organism.Through polymerase chain reaction(PCR)amplification,restriction enzyme digestion,ligation,transformation,and Sanger sequencing,we assessed the operational efficiency and cloning fidelity of both strategies.Our results demonstrated that Golden Gate assembly,leveraging type IIS restriction enzymes and simultaneous ligation,significantly enhanced cloning efficiency and precision,particularly for seamless multi-fragment assembly.In contrast,the classical cloning approach maintained certain advantages in simplicity and robustness for specific experimental conditions.Challenges encountered during transformation and sequencing highlighted the critical impact of technical accuracy on experimental outcomes.This study underscores the importance of selecting appropriate cloning methodologies tailored to experimental objectives and laboratory capabilities,providing a foundation for optimized molecular cloning workflows in future synthetic biology and biotechnology applications. 展开更多
关键词 Golden Gate Assembly Classical Cloning Escherichia coli Molecular Cloning DNA Assembly Recombinant DNA Technology Transformation Effi ciency Synthetic Biology
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Characterization and genomics analysis of phage PGX1 against multidrug-resistant enterotoxigenic E.coli with in vivo and in vitro efficacy assessment
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作者 Dayue Hu Ping Qian +5 位作者 Dongyang Gao Xinxin Li Linkang Wang Hongyue Ji Shuang Wang Xiangmin Li 《Animal Diseases》 2025年第1期85-100,共16页
Enterotoxigenic E.coli is one of the bacterial pathogens contributing to the global resistance crisis in public health and animal husbandry.The problem of antibiotic resistance is becoming more and more serious,and ph... Enterotoxigenic E.coli is one of the bacterial pathogens contributing to the global resistance crisis in public health and animal husbandry.The problem of antibiotic resistance is becoming more and more serious,and phage is con-sidered one of the potential alternatives to antibiotics that could be utilized to treat bacterial infections.Our study isolated and identified a lytic phage PGX1 against multidrug-resistant enterotoxigenic E.coli EC6 strain from sew-age.The phage lysis profile revealed that PGX1 exhibited a lytic effect on multidrug-resistant enterotoxigenic E.coli strains of serotype O60.Through phage whole genome sequencing and bioinformatics analysis,PGX1 was found to be the class Caudoviricetes,family Autographiviridae,genus Teseptimavirus.The length of the PGX1 genome is about 37,009 bp,containing 54 open reading frames(ORFs).Notably,phage PGX1 lacks any lysogenic-related genes or virulence genes.Furthermore,phage PGX1 demonstrates strong adaptability,tolerance,and stability in various pH(pH4-10)and temperatures(4–40°C).The in vivo and in vitro tests demonstrated that phage PGX1 significantly removes and inhibits the formation of multidrug-resistant EC6 biofilm and effectively controls the Galleria mel-lonella larvae and enterotoxigenic E.coli EC6 during mice infection.In conclusion,the above findings demonstrated that phage PGX1 may be a novel antimicrobial agent to control multidrug-resistant E.coli infections. 展开更多
关键词 Enterotoxigenic E.coli Multidrug-resistant bacteria Phage PGX1
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提高碱性磷酸酶在E.coli胞内表达的可溶性及活性 被引量:2
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作者 杨丹燕 林陈水 《浙江工业大学学报》 CAS 北大核心 2009年第4期372-375,共4页
以E.coliDH5α基因组为模板PCR扩增得到无信号肽的碱性磷酸酶基因片段,与胞内融合表达型T载体连接得到重组质粒,转化表达宿主E.coliBL21(DE3)和E.coliorigami(DE3),经0.1 mM IPTG诱导表达,超声破碎细胞后,SDS-PAGE分析可溶性,融合蛋白在... 以E.coliDH5α基因组为模板PCR扩增得到无信号肽的碱性磷酸酶基因片段,与胞内融合表达型T载体连接得到重组质粒,转化表达宿主E.coliBL21(DE3)和E.coliorigami(DE3),经0.1 mM IPTG诱导表达,超声破碎细胞后,SDS-PAGE分析可溶性,融合蛋白在E.coliorigami(DE3)中的可溶蛋白含量比E.coliBL21(DE3)中高.融合蛋白的可溶部分经Ni2+螯合亲和纯化,纯化后E.coliorigami(DE3)中蛋白活性比E.coliBL21(DE3)中明显提高,达到1 614.3U/mg蛋白. 展开更多
关键词 碱性磷酸酶 E.coli BL21(DE3) E.coliorigami(DE3) 可溶性 活性
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Evaluation of media for simultaneous enumeration of total coliform and Escherichia coli in drinking water supplies by membrane filtration techniques 被引量:1
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作者 WANG Dunling FIESSEL Wanda 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第3期273-277,共5页
This study evaluated three different dehydrated media for simultaneous detection and enumeration of total coliform (TC) and Escherichia coil in drinking water samples with a standard membrane filtration procedure. T... This study evaluated three different dehydrated media for simultaneous detection and enumeration of total coliform (TC) and Escherichia coil in drinking water samples with a standard membrane filtration procedure. The experiment indicated that the differential coliform agar (DCA) medium was the most effective among the tested media in enumerating TC and E. coil, without the need for extensive accompanying confirmation tests. The results for DCA medium were highly reproducible for both TC and E. coil with standard deviation of 6.0 and 6.1, respectively. A high agreement (82%) was found between DCA and m-Endo media on 152 drinking water samples in terms of TC positive. The DCA medium also reduced concealment of background bacteria. 展开更多
关键词 drinking water differential coliform agar (DCA) total coliform (TC) E. coli membrane filtration (MF)
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Preclinical and clinical evidence of the association of colibactinproducing Escherichia coli with anxiety and depression in colon cancer 被引量:1
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作者 Fabien Rondepierre Maëva Meynier +11 位作者 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 《World Journal of Gastroenterology》 SCIE CAS 2024年第21期2817-2826,共10页
BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin... BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The 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 approaches.METHODS Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric interview.Results were compared according to the CoPEC colonization.In parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC strain.Their 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 did.This 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 strain.CONCLUSION This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties. 展开更多
关键词 Colorectal cancer colibactin Escherichia coli colibactin-producing Escherichia coli Inflammation ANXIETY DEPRESSION Behavior
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Sterilization Effects of Bacterial Inhibitor on Escherichia coli in Cattle Manure Compost 被引量:20
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作者 敖日格乐 王纯洁 +4 位作者 于俊娥 斯木吉德 吴美云 程佳 陈昆 《Agricultural Science & Technology》 CAS 2008年第6期154-156,共3页
[Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis fo... [Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis for cattle manure harmless treatment.[Method] Both experimental groups supplemented with 2.0% bacterial inhibitor and control groups without bacterial inhibitor were cultured under different temperatures(20,30,37,50,60 ℃)to determine the optimal composing temperature.Under 30 ℃,different bacterial inhibitor doses(0,2.0%,2.5%,3.0%)were added into the compost to obtain the optimal bacterial inhibitor addition dose.[Result] 30,50 and 60 ℃ were ideal temperatures for sterilization of E.coli.Under 30 ℃,E.coli couldn't be detected in 2.5% dose group and 3.0% dose group after culture for 48 h,demonstrating no less than 2.5% bacterial inhibitor should be added.[Conclusion] It has an important significance to enhance the sterilization effects on E.coli by adding CaCN2 into cattle manure compost especially in winter. 展开更多
关键词 BACTERIAL INHIBITOR Cattle MANURE COMPOSTING ESCHERICHIA coli
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一种实用的基于化学发光和磁性纳米颗粒的E.coli O157:H7免疫鉴定方法 被引量:12
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作者 李智洋 何磊 +5 位作者 何农跃 史智扬 汪华 李松 刘洪娜 戴亚斌 《化学学报》 SCIE CAS CSCD 北大核心 2010年第3期251-256,共6页
化学发光磁酶免疫已经被应用于检测病原体,但是由于针对相应病原体的抗体筛选和修饰等的步骤耗时费力,不适于对多种病原体进行筛查.制备了兔抗大肠杆菌(E.coli)O157:H7的免疫磁性纳米颗粒,富集病原菌后与鼠抗E.coli O157:H7的单克隆抗... 化学发光磁酶免疫已经被应用于检测病原体,但是由于针对相应病原体的抗体筛选和修饰等的步骤耗时费力,不适于对多种病原体进行筛查.制备了兔抗大肠杆菌(E.coli)O157:H7的免疫磁性纳米颗粒,富集病原菌后与鼠抗E.coli O157:H7的单克隆抗体形成双抗夹心,采用碱性磷酸酶标记的马抗鼠IgG与单抗结合,加入碱性磷酸酶的化学发光底物试剂3-(2'-螺旋金刚烷)-4-甲氧基-4-(3''-羟基)苯-1,2-二氧杂环丁烷磷酸检测化学发光.实验研究了底物缓冲液、碱性磷酸酶浓度对化学发光强度的影响,比较了NaBH4和甘氨酸对免疫磁珠剩余活性醛基的封闭效果以及本方法检测E.coli O157:H7的特异性和敏感性.结果表明,碱性磷酸酶与底物在c缓冲液中反应的化学发光强度最高,碱性磷酸酶浓度决定了化学发光的强度和持续时间,NaBH4对活性醛基的封闭效果优于甘氨酸,以D群宋内氏志贺氏菌、B群福氏志贺氏菌、鼠伤寒沙门氏菌、金黄色葡萄球菌和霍乱弧菌及E.coli Top10f'为对照的比较实验显示,该检测方法具有良好的特异性,以1mL的菌液为检测体积时对E.coli O157:H7的检测灵敏度为103cell/mL,整个方法的检测时间约为3h.该方法适用于对多样本进行筛查. 展开更多
关键词 E.coli O157:H7 酶联免疫检测法 化学发光 磁性纳米颗粒
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口服益生菌Escherichia coli Nissle 1917调控断奶仔猪空肠黏膜屏障功能的机理研究 被引量:6
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作者 唐志如 邓欢 +2 位作者 孙卫忠 张小龙 张翥 《畜牧兽医学报》 CAS CSCD 北大核心 2014年第1期78-86,共9页
旨在探讨口服益生菌Escherichia coli(E.coli)Nissle 1917调控病原菌E.coli Abbottstown攻毒或未攻毒21d断奶仔猪肠道屏障功能的机理。将20头21d断奶仔猪((6.35±0.38)kg)随机分为4组:(1)饲喂基础日粮的对照组(CON);(2)正试期口服E.... 旨在探讨口服益生菌Escherichia coli(E.coli)Nissle 1917调控病原菌E.coli Abbottstown攻毒或未攻毒21d断奶仔猪肠道屏障功能的机理。将20头21d断奶仔猪((6.35±0.38)kg)随机分为4组:(1)饲喂基础日粮的对照组(CON);(2)正试期口服E.coli Nissle 1917组(EcN);(3)预试期E.coli Abbottstown攻毒组(EcA);(4)预试期E.coli Abbottstown攻毒和正试期口服E.coli Nissle 1917组(EcN+EcA)。每个处理5个重复,每个重复1头仔猪。试验分为3d预试期和21d正试期。预试期EcA和EcN+EcA组的断奶仔猪接种5×10~9E.coli Abbottstown。正试期EcN和EcN+EcA组仔猪每天每头口服1×10~10E.coli Nissle 1917。试验结果表明,未攻毒的断奶仔猪中,与CON相比,口服1×10~10E.coli Nissle 1917能显著改善生长性能(P<0.05),降低腹泻率,提高oCcludin蛋白水平(P<0.05),显著降低空肠黏膜calprotectin蛋白水平(P<0.05),显著下调空肠黏膜蛋白激酶R(Protein kinase R,PKR)、toll样受体-2(Toll-like receptor-2,TLR-2)和真核起始因子-5A(eukaryotic initiation factor-5A,eIF-5A)mRNA的相对表达丰度(P<0.05),上调空肠黏膜内皮生长因子(Endothelial growth factor,EGF)、肝细胞生长因子(Hepatocyte growth factor,HGF)、胰岛素样生长因子(Insulin-like growth factor,IGF-I)、三叶肽因子-3(trefoil peptide factor-3,TFF-3)mRNA的相对表达丰度(P<0.05);在E.coli Abbottstown攻毒的断奶仔猪中,与EcA组相比,口服1×10~10E.coli Nissle 1917能显著改善生长性能(P<0.05),降低腹泻率,降低血清二胺氧化酶(DAO)活性(P<0.05)和一氧化氮(NO)含量(P<0.05),下调空肠黏膜PKR、eIF-5A和TLR-2 mRNA相对表达丰度(P<0.05),显著降低空肠黏膜calprotectin蛋白水平和淋巴细胞数量(P<0.05),显著提高空肠黏膜oCcludin蛋白水平(P<0.05),上调空肠黏膜IGF-I、HGF、TFF-3和EGF mRNA相对表达丰度(P<0.05)。本试验结果提示,口服1×10~10E.coli Nissle 1917能降低病原大肠杆菌攻毒或未攻毒21日龄断奶仔猪空肠黏膜屏障功能的损伤。 展开更多
关键词 益生菌 ESCHERICHIA coli Nissle 1917 仔猪 肠道屏障 OCCLUDIN CALPROTECTIN
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重组E.coli工程菌高密度培养生产人源型胶原蛋白 被引量:68
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作者 范代娣 段明瑞 +4 位作者 米钰 宋纪蓉 惠俊峰 王德伟 王国柱 《化工学报》 EI CAS CSCD 北大核心 2002年第7期752-754,共3页
Several technical parameters were studied during the fermentation of recombinant E.coli for the production of collagen-like biopolymer.The effects of dissolved oxygen as well as glucose concentration on fermentation w... Several technical parameters were studied during the fermentation of recombinant E.coli for the production of collagen-like biopolymer.The effects of dissolved oxygen as well as glucose concentration on fermentation were observed.The OD 600 value could reach 98 when dissolved oxygen was controlled at 50% and glucose around 1%.The production of human-like collagen with a yield of 29.4% was obtained. 展开更多
关键词 重组E.coli工程菌 高密度发酵 类人胶原蛋白 培养工艺 发酵
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乳酸链球菌素与大黄联合作用对牛源致病性Escherichia coli O_(78)的抑菌作用 被引量:9
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作者 张燕 敖日格乐 +3 位作者 王纯洁 姜晶 赵称赫 曹晓波 《中国农业大学学报》 CAS CSCD 北大核心 2016年第7期92-97,共6页
为研究乳酸链球菌素(nisin)和大黄联合药效对牛源致病性大肠杆菌的抑菌作用,通过二倍稀释法测定nisin、大黄、抗生素及联合用药的最小抑菌浓度(MIC);微板法测定各药物MIC剂量下致病性大肠秆菌的生长曲线、碱性磷酸酶(AKP)以及总蛋白含... 为研究乳酸链球菌素(nisin)和大黄联合药效对牛源致病性大肠杆菌的抑菌作用,通过二倍稀释法测定nisin、大黄、抗生素及联合用药的最小抑菌浓度(MIC);微板法测定各药物MIC剂量下致病性大肠秆菌的生长曲线、碱性磷酸酶(AKP)以及总蛋白含量。结果表明:1)nisin单独使用对Escherichia coli O_(78)无抑菌效果;大黄单独使用时MIC为62.5mg/mL,抗生素的MIC为0.016mg/mL,nisin和大黄联合使用MIC分别为0.333和10.417mg/mL。2)大黄和nisin联合药效,能够有效抑制E.coli O_(78)的生长,缩短对数期,效果优于大黄组(P<0.05),仅次于抗生素组(P<0.05)。3)nisin和大黄联合使用对E.coli O_(78)的细胞壁和细胞膜有很强的破坏性,导致AKP和菌体总蛋白指数的升高,效果显著优于抗生素、大黄(P<0.05)。由此可见,大黄和nisin联合作用E.coli O_(78)时,杀菌效果高于抗生素、大黄,抑菌效果高于大黄,但低于抗生素。 展开更多
关键词 乳酸链球菌素 大黄 联合作用 抑菌机理 E.coli O78 最小抑菌浓度
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