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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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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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The virulence regulator AbsR in avian pathogenic Escherichia coli has pleiotropic effects on bacterial physiology
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作者 Dongfang Zhao Haobo Zhang +4 位作者 Xinyang Zhang Fengwei Jiang Yijing Li Wentong Cai Ganwu Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期649-668,共20页
Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic E.coli(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and blood.MprA(microcin producti... Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic E.coli(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and blood.MprA(microcin production regulation,locus A,herein renamed AbsR,a blood survival regulator),a member of the MarR(multiple antibiotic resistance regulator)transcriptional regulator family,governs the expression of capsule biosynthetic genes in human ExPEC and represents a promising druggable target for antimicrobials.However,a deep understanding of the AbsR regulatory mechanism as well as its regulon is lacking.In this study,we present a systems-level analysis of the APEC AbsR regulon using ChIP-Seq(chromatin immunoprecipitation sequencing)and RNA-Seq(RNA sequencing)methods.We found that AbsR directly regulates 99 genes and indirectly regulates 667 genes.Furthermore,we showed that:1)AbsR contributes to antiphagocytotic effects by macrophages and virulence in a mouse model for systemic infection by directly activating the capsular gene cluster;2)AbsR positively impacts biofilm formation via direct regulation of the T2SS(type II secretion system)but plays a marginal role in virulence;and 3)AbsR directly upregulates the acid tolerance signaling system EvgAS to withstand acid stress but is dispensable in ExPEC virulence.Finally,our data indicate that the role of AbsR in virulence gene regulation is relatively conserved in ExPEC strains.Altogether,this study provides a comprehensive analysis of the AbsR regulon and regulatory mechanism,and our data suggest that AbsR likely influences virulence primarily through the control of capsule production.Interestingly,we found that AbsR severely represses the expression of the type I-F CRISPR(clustered regularly interspaced short palindromic repeats)-Cas(CRISPR associated)systems,which could have implications in CRISPR biology and application. 展开更多
关键词 avian pathogenic Escherichia coli(APEC) extraintestinal pathogenic Escherichia coli(ExPEC) AbsR RNA-SEQ CHIP-SEQ gene regulation
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Oleanolic acid improved intestinal immune function by activating and potentiating bile acids receptor signaling in E. coli-challenged piglets 被引量:3
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作者 Chenyu Xue Hongpeng Jia +8 位作者 Rujing Cao Wenjie Cai Weichen Hong Jianing Tu Songtao Wang Qianzhi Jiang Chongpeng Bi Anshan Shan Na Dong 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2137-2155,共19页
Background Infection with pathogenic bacteria during nonantibiotic breeding is one of the main causes of animal intestinal diseases.Oleanolic acid(OA)is a pentacyclic triterpene that is ubiquitous in plants.Our previo... Background Infection with pathogenic bacteria during nonantibiotic breeding is one of the main causes of animal intestinal diseases.Oleanolic acid(OA)is a pentacyclic triterpene that is ubiquitous in plants.Our previous work demonstrated the protective effect of OA on intestinal health,but the underlying molecular mechanisms remain unclear.This study investigated whether dietary supplementation with OA can prevent diarrhea and intestinal immune dysregulation caused by enterotoxigenic Escherichia coli(ETEC)in piglets.The key molecular role of bile acid receptor signaling in this process has also been explored.Results Our results demonstrated that OA supplementation alleviated the disturbance of bile acid metabolism in ETEC-infected piglets(P<0.05).OA supplementation stabilized the composition of the bile acid pool in piglets by regulating the enterohepatic circulation of bile acids and significantly increased the contents of UDCA and CDCA in the ileum and cecum(P<0.05).This may also explain why OA can maintain the stability of the intestinal microbiota structure in ETEC-challenged piglets.In addition,as a natural ligand of bile acid receptors,OA can reduce the severity of intestinal inflammation and enhance the strength of intestinal epithelial cell antimicrobial programs through the bile acid receptors TGR5 and FXR(P<0.05).Specifically,OA inhibited NF-κB-mediated intestinal inflammation by directly activating TGR5 and its downstream c AMP-PKA-CREB signaling pathway(P<0.05).Furthermore,OA enhanced CDCA-mediated MEK-ERK signaling in intestinal epithelial cells by upregulating the expression of FXR(P<0.05),thereby upregulating the expression of endogenous defense molecules in intestinal epithelial cells.Conclusions In conclusion,our findings suggest that OA-mediated regulation of bile acid metabolism plays an important role in the innate immune response,which provides a new diet-based intervention for intestinal diseases caused by pathogenic bacterial infections in piglets. 展开更多
关键词 Bile acid receptors Enterotoxigenic Escherichia coli Intestinal innate immunity Oleanolic acid
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Antibacterial mechanism of kojic acid and tea polyphenols against Escherichia coli O157:H7 through transcriptomic analysis 被引量:3
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作者 Yilin Lin Ruifei Wang +4 位作者 Xiaoqing Li Keren Agyekumwaa Addo Meimei Fang Yehui Zhang Yigang Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期736-747,共12页
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag... Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry. 展开更多
关键词 Kojic acid Tea polyphenols Antibacterial mechanism Escherichia coli O157:H7 RNA-SEQ
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重组体pET-28a-alkB/E.coli降解页岩油泥石油烃的功能研究
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作者 李雪菲 句泽林 +3 位作者 齐婷婷 郑乾璐 李喜梅 余丽芸 《山东化工》 CAS 2024年第19期239-243,共5页
为了降解页岩油泥中的石油烃,构建基因工程菌,表达石油烃降解关键酶以提高油泥的降解效果。以Pseudomonas qingdaonensis基因组为模板扩增alkB基因,连接至载体pET-28a,转化至E.coli BL21(DE3)中,SDS-PAGE和Western-blot鉴定表达的外源... 为了降解页岩油泥中的石油烃,构建基因工程菌,表达石油烃降解关键酶以提高油泥的降解效果。以Pseudomonas qingdaonensis基因组为模板扩增alkB基因,连接至载体pET-28a,转化至E.coli BL21(DE3)中,SDS-PAGE和Western-blot鉴定表达的外源蛋白。pET-28a-alkB/E.coli处理原油和页岩油泥,采用气相色谱法评估降解效果。发现alkB基因在大肠杆菌中能表达外源蛋白,且14 d原油及页岩油泥的降解率分别为47.5%和47.1%,表明重组体pET-28a-alkB/E.coli具备降解页岩油泥石油烃的功能。 展开更多
关键词 烷烃单加氧酶alkB 生物降解 E.coli BL21(DE3) 页岩油污泥 气相色谱法
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Exploring the modulatory role of bovine lactoferrin on the microbiome and the immune response in healthy and Shiga toxin‑producing E.coli challenged weaned piglets
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作者 Matthias Dierick Ruben Ongena +2 位作者 Daisy Vanrompay Bert Devriendt Eric Cox 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1278-1291,共14页
Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have con... Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses. 展开更多
关键词 E.coli Immune modulation LACTOFERRIN MICROBIOME
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Impact of an oligosaccharide-based polymer on the metabolic profiles and microbial ecology of weanling pigs experimentally infected with a pathogenic E.coli
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作者 Kwangwook Kim Cynthia Jinno +4 位作者 Xunde Li David Bravo Eric Cox Peng Ji Yanhong Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期749-764,共16页
Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to ... Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to carbadox.The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic.The relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q<0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 PI.Conclusions The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is needed.However,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer. 展开更多
关键词 CARBADOX Colon microbiota Enterotoxigenic E.coli F18 Metabolomics Oligosaccharide-based polymer Weaned pigs
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重组E.coli宿主中质粒DNA拷贝数qPCR检测方法的建立及验证
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作者 王魁 殷吉祥 +3 位作者 程之铭 郭冰峰 郝一楠 潘若文 《中国生物制品学杂志》 CAS CSCD 2024年第10期1263-1267,1274,共6页
目的建立重组E.coli宿主中质粒DNA(pDNA)拷贝数的qPCR检测方法,并进行验证,以期为mRNA疫苗研发提供可靠的检测方法。方法根据E.coli Top10基因组DNA序列设计用于qPCR扩增的引物及探针,并优化引物浓度。提取重组E.coli/pUC57-HA的全DNA(... 目的建立重组E.coli宿主中质粒DNA(pDNA)拷贝数的qPCR检测方法,并进行验证,以期为mRNA疫苗研发提供可靠的检测方法。方法根据E.coli Top10基因组DNA序列设计用于qPCR扩增的引物及探针,并优化引物浓度。提取重组E.coli/pUC57-HA的全DNA(宿主DNA+pDNA),以其为模板,建立pDNA拷贝数的qPCR检测方法,并验证方法的线性范围、特异性及重复性。将重组E.coli/pUC57-HA于37℃培养24 h,每2 h取样,采用建立的方法检测pDNA拷贝数。结果确定最佳引物(F/R)浓度均为0.5μmol/L。重组E.coli/pUC57-HA全DNA在10~1~10~5倍稀释范围内,与Ct呈良好的线性关系,R^(2)均=1.00;E.coli/pUC57-HA及E.coli Top10的扩增结果为阳性,阴性对照(ddH_(2)O)未见扩增曲线;3次重复检测重组E.coli/pUC57-HA的pDNA拷贝数CV<5%。E.coli/pUC57-HA培养0~6 h期间pDNA拷贝数呈平稳趋势,6~12 h期间呈下降趋势,12~16 h期间呈增长趋势,16~24 h又趋于平稳。结论建立的qPCR法具有良好的特异性及重复性,可用于重组E.coli宿主中pDNA拷贝数的检测,有效监测菌株培养过程中pDNA含量变化。 展开更多
关键词 E.coli 质粒DNA拷贝数 qPCR mRNA疫苗
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