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Sample records for ampicillin resistant escherichia

  1. Distribution and possible transmission of ampicillin- and nalidixic acid-resistant Escherichia coli within the broiler industry.

    Science.gov (United States)

    Bortolaia, Valeria; Bisgaard, Magne; Bojesen, Anders Miki

    2010-05-19

    This study was performed to determine the origin and transmission of beta-lactam- and (fluoro)quinolone-resistant Escherichia coli in healthy, untreated broiler flocks. We focused on the dynamics of bacteria resistant to critically important antimicrobials for public and veterinary health in view of the possible link between antimicrobial resistant bacteria in farm animals and humans. By processing faecal samples collected with the sock method in broiler parent and broiler flocks, E. coli resistant to ampicillin and nalidixic acid were frequently isolated, while resistance to ciprofloxacin was detected at a very low frequency, and resistance to cephalosporins was not detected. Similarly, resistance to ampicillin and nalidixic acid were the only phenotypes detected in a collection of clinical E. coli isolates associated with first-week-mortality in broiler parent chicks. Although antimicrobial resistant E. coli were genetically diverse by means of amplified fragment length polymorphism (AFLP) typing, indistinguishable isolates were present in different flocks, including isolates from broiler parent chicks, broiler parents and broilers. In the absence of apparent selective pressure, the genotypic heterogeneity that we describe is likely the consequence of multiple introductions of antimicrobial resistant bacteria into the production system. The confinement under which broilers are raised limits the possibilities of bacterial transmission among different flocks. Our findings are consistent with vertical transmission of ampicillin- and nalidixic acid-resistant E. coli through the broiler production system. The persistence of antimicrobial resistant E. coli in healthy, untreated chicken flocks emphasises the need of careful evaluation of therapeutic options at any level of the broiler production. PMID:19945232

  2. Cloning and expression in Escherichia coli of the Azospirillum brasilense Sp7 gene encoding ampicillin resistance.

    OpenAIRE

    Verreth, C; Cammue, B; Swinnen, P; Crombez, D; Michielsen, A; Michiels, K.; Gool, A. van; Vanderleyden, J.

    1989-01-01

    The Azospirillum brasilense ATCC 29145 gene coding for beta-lactamase was cloned in Escherichia coli. The gene was expressed in E. coli from its own promoter as a 30-kilodalton protein, conferring resistance to high levels of beta-lactam antibiotics. The DNA sequence containing the beta-lactamase gene was found to be highly amplified in the Azospirillum genome, scattered in the chromosomal as well as in the plasmidic DNA.

  3. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    The genetic background for beta-lactamase-mediated resistance to beta-lactam antibiotics was examined by PCR and sequencing in 160 ampicillin-resistant isolates (109 Escherichia coli and 51 Salmonella) obtained from healthy and diseased food animals in Denmark. Sequencing revealed three different...... variants of bla(TEM-1), of which bla(TEM-1b) was the most frequently detected (80 E. coli and 47 Salmonella), followed by bla(TEM-1a) (eight E. coli, one Salmonella) and bla(TEM-1c) (seven E. coli). A few isolates were found to express OXA, TEM-30, or PSE beta-lactamases. Mutations in the ampC promoter...... leading to increased production of the AmpC beta-lactamase were demonstrated in 11 cefoxitin-resistant or intermediate E. coli isolates. Nine of these isolates did not contain any bla(TEM) genes, whereas the remaining two did. No genes encoding SHV or extended-spectrum beta-lactamases were detected. Two...

  4. Genetic markers for detection of Escherichia coli K-12 harboring ampicillin-resistance plasmid from an industrial wastewater treatment effluent pond.

    Science.gov (United States)

    Simões, G A R; Xavier, M A S; Oliveira, D A; Menezes, E V; Magalhães, S S G; Gandra, J A C D; Xavier, A R E O

    2016-01-01

    Biotechnology industries that use recombinant DNA technology are potential sources for release of genetically modified organisms to the environment. Antibiotic-resistance marker genes are commonly used for recombinant bacteria selection. One example is the marker gene coding for β-lactamase (bla) in plasmids found in Escherichia coli K-12. The aim of this study was to provide an approach to develop a molecular method for genetic marker detection in E. coli K-12 harboring bla genes from an industrial wastewater treatment effluent pond (IWTEP). For the detection of bla and Achromobacter lyticus protease I (api) genes in samples from IWTEP, we employed multiplex polymerase chain reaction (PCR) using E. coli K-12 genetic marker detection primers, previously described in the literature, and primers designed in our laboratory. The microbiological screening method resulted in 22 bacterial colony-forming units isolated from three different IWTEP harvesting points. The multiplex PCR amplicons showed that five isolates were positive for the bla gene marker and negative for the E. coli K-12 and api genes. The 16S rRNA regions of positive microorganisms carrying the bla gene were genotyped by the MicroSeq®500 system. The bacteria found were Escherichia spp (3/5), Chromobacterium spp (1/5), and Aeromonas spp (1/5). None of the 22 isolated microorganisms presented the molecular pattern of E. coli K-12 harboring the bla gene. The presence of microorganisms positive for the bla gene and negative for E. coli K-12 harboring bla genes at IWTEP suggests that the ampicillin resistance found in the isolated bacteria could be from microorganisms other than the E. coli K-12 strain harboring plasmid. PMID:27323199

  5. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    variants of bla(TEM-1), of which bla(TEM-1b) was the most frequently detected (80 E. coli and 47 Salmonella), followed by bla(TEM-1a) (eight E. coli, one Salmonella) and bla(TEM-1c) (seven E. coli). A few isolates were found to express OXA, TEM-30, or PSE beta-lactamases. Mutations in the ampC promoter...... leading to increased production of the AmpC beta-lactamase were demonstrated in 11 cefoxitin-resistant or intermediate E. coli isolates. Nine of these isolates did not contain any bla(TEM) genes, whereas the remaining two did. No genes encoding SHV or extended-spectrum beta-lactamases were detected. Two...

  6. Distribution of phylogroups and co-resistance to antimicrobial agents in ampicillin resistant Escherichia coli isolated from healthy humans and from patients with bacteraemia

    DEFF Research Database (Denmark)

    Haugaard, A.; Hammerum, A. M.; Porsbo, Lone Jannok;

    resistance in faecal and blood isolates (F/B) was: tetracycline (48%/48%), gentamicin (0%/10%), ciprofloxacin (3%,13%), sulfonamide (68%/77%) and trimethoprim (39%/39%). Conclusion: B2 was the most prevalent phylogroup found both in faecal isolates collected from healthy humans and in blood isolates from...

  7. Emergence of ampicillin-resistant Enterococcus faecium in Danish hospitals

    DEFF Research Database (Denmark)

    Lester, Camilla H; Sandvang, Dorthe; Olsen, Stefan;

    2008-01-01

    BACKGROUND: Ampicillin-resistant Enterococcus faecium isolates are reported in increasing numbers in many European hospitals. The clonal complex 17 (CC17) characterized by ampicillin resistance has been associated with nosocomial E. faecium outbreaks and infections in five continents. The aim was...... to investigate how prevalent ampicillin resistance is in clinical E. faecium isolates from Denmark and to investigate their clonal affiliation, especially to CC17. METHODS: Microbiology data from 2002 through 2006 on E. faecium and Enterococcus faecalis blood isolates was received from Departments of...... Clinical Microbiology in 11 Danish counties. From January 2004 through December 2004, we collected 275 clinical enterococci from four of these departments. Multilocus sequence typing (MLST) and PFGE were performed on the 84 ampicillin-resistant E. faecium isolates from this collection. RESULTS: A 68...

  8. Ampicillin Resistance and Outcome Differences in Acute Antepartum Pyelonephritis

    Directory of Open Access Journals (Sweden)

    Laura G. Greer

    2008-01-01

    Full Text Available Objective. To measure the incidence of ampicillin-resistant uropathogens in acute antepartum pyelonephritis and to determine if patients with resistant organisms had different clinical outcomes. Study design. This was a secondary analysis of a prospective cohort study of pregnant women admitted with pyelonephritis, diagnosed by standard clinical and laboratory criteria. All patients received ampicillin and gentamicin. Results. We identified 440 cases of acute pyelonephritis. Seventy-two percent (316 cases had urine cultures with identification of organism and antibiotic sensitivities. Fifty-one percent of uropathogens were ampicillin resistant. The patients with ampicillin-resistant organisms were more likely to be older and multiparous. There were no significant differences in hospital course (length of stay, days of antibiotics, ECU admission, or readmission. Patients with ampicillin-resistant organisms did not have higher complication rates (anemia, renal dysfunction, respiratory insufficiency, or preterm birth. Conclusion. A majority of uropathogens were ampicillin resistant, but no differences in outcomes were observed in these patients.

  9. Extended-spectrum beta-lactamase production among ampicillin-resistant Escherichia coli strains from chicken in Enugu State, Nigeria Produção de beta-lactamase de espectro expandido por cepas de Escherichia coli resistentes a ampicilina isoladas de frango em Enugu State, Nigéria

    OpenAIRE

    Chah, K.F.; Oboegbulem, S. I.

    2007-01-01

    One hundred and seventy-two ampicillin-resistant E. coli strains isolated from commercial chickens in Enugu State, Nigeria, were screened for beta-lactamase production using the broth method with nitrocefin® as the chromogenic cephalosporin to detect enzyme production. Beta-lactamase producing strains were further examined for extended-spectrum beta-lactamase (ESBL) production using the Oxoid combination discs method. One hundred and seventy (98.8%) of the 172 ampicillin-resistant E. coli str...

  10. Inhibition of Ampicillin-resistance in Bacteria by Modified DNAzymes

    Institute of Scientific and Technical Information of China (English)

    CHEN Fei; LI Zhe; YANG Shuo; WANG Rui-jian; LIU Bin; SONG Yu-ming; SUN Yan-hong; HAO Dong-yun; NG Xlao-ping

    2008-01-01

    To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous β-lactamase,we designed three 10-23 DNAzymes(DZ1,Dz2,Dz3) targeting the coding region of β-lactamase mRNA and examined their inhibitory capabilities of the ampicillin-resistance of TEM-1 and TEM-3 bacteria,Dz1 was a traditional 10-23 DNAzyme,Dz2 was the mutant of Dz1 by addition of the protected nucleotide to each arm of the enzyme,and Dz3 was a mutant of DZ1 at antisense arms of which phosphorothioate modifications were made,Kinetic analysis,bacterial growth,and β-lactamase activity measurement showed that all the three DNAzymes worked efficiently in vitro and in vivo,A 9 hours bacterial growth inhibition test showed that the inhibition rates of TEM-1 bacteria by Dz1,Dz2,and Dz3 were 27%,50%,and 29%,respectively,In addition,the inhibition rates of TEM-3 bacteria by those three DNAzymes were found to be 49%,58%,and 45%,respectively,The current findings suggest that DNAzymes may become potential candidates of alternative inhibitors for bacteria drug-resistance.

  11. Extended-spectrum beta-lactamase production among ampicillin-resistant Escherichia coli strains from chicken in Enugu State, Nigeria Produção de beta-lactamase de espectro expandido por cepas de Escherichia coli resistentes a ampicilina isoladas de frango em Enugu State, Nigéria

    Directory of Open Access Journals (Sweden)

    K.F. Chah

    2007-12-01

    Full Text Available One hundred and seventy-two ampicillin-resistant E. coli strains isolated from commercial chickens in Enugu State, Nigeria, were screened for beta-lactamase production using the broth method with nitrocefin® as the chromogenic cephalosporin to detect enzyme production. Beta-lactamase producing strains were further examined for extended-spectrum beta-lactamase (ESBL production using the Oxoid combination discs method. One hundred and seventy (98.8% of the 172 ampicillin-resistant E. coli strains produced beta-lactamase enzyme. Sixteen (9.4% beta-lactamase producers were phenotypically confirmed to produce ESBLs. Six of the ESBL producing strains were only detected with ceftazidime versus ceftazidime/clavulanate combination while ten of the ESBL producers were detected with cefotaxime versus cefotaxime/clavulanate combination. Chicken may serve as a reservoir of ESBL-producing E. coli strains which could be transferred to man and other animals.Cento e setenta e duas cepas de Escherichia coli resistentes a ampicilina isoladas de frangos em Enugu State, Nigéria, foram avaliadas quanto à produção de beta-lactamase através do uso de método em caldo com nitrocefin® como indicador cromogênico da produção da enzima. Em seguida, as cepas produtoras de beta-lactamase foram examinadas quanto à produção de beta-lactamase de espectro expandido (ESBL através do método de discos combinados Oxoid. Entre as cepas de Escherichia coli resistentes a ampicilina, cento e setenta (98,8% produziram beta-lactamase. Testes fenotípicos indicaram que dezesseis (9,4% das cepas produtoras de beta-lactamase produziram ESBL. Seis cepas produtoras de ESBL foram detectadas apenas com a combinação ceftazidima versus cefotaxime/clavulanato, enquanto dez cepas produtoras de ESBL foram detectadas com a combinação cefotaxime versus cefotaxime/clavulanato. Frangos podem ser reservatório de cepas de E.coli produtoras de ESBL, que podem ser transferidos para o homem

  12. Susceptibilities of 200 penicillin-susceptible and -resistant pneumococci to piperacillin, piperacillin-tazobactam, ticarcillin, ticarcillin-clavulanate, ampicillin, ampicillin-sulbactam, ceftazidime, and ceftriaxone.

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    Pankuch, G A; Jacobs, M. R.; Appelbaum, P C

    1994-01-01

    MICs of eight beta-lactams (piperacillin, piperacillin-tazobactam, ticarcillin, ticarcillin-clavulanate, ampicillin, ampicillin-sulbactam, ceftazidime, and ceftriaxone) were determined by agar dilution against 64 penicillin-susceptible, 70 intermediately penicillin-resistant, and 66 fully penicillin-resistant pneumococci. The MICs of piperacillin with and without tazobactam for 90% of the susceptible, intermediately resistant, and resistant strains tested (MIC90s) were < or = 0.064, 2.0, and ...

  13. Staphylococcus aureus ampicillin-resistant from the odontological clinic environment.

    Science.gov (United States)

    Bernardo, Wagner Luis de Carvalho; Boriollo, Marcelo Fabiano Gomes; Gonçalves, Reginaldo Bruno; Höfling, José Francisco

    2005-01-01

    The aim of this research was to evaluate the prevalence of Staphylococcus spp. and S. aureus in the odontological clinic environment (air), their production of beta-lactamase and antibacterial susceptibility to the major antibiotics utilized in medical particle. During 12 months of samples collect were isolated 9775 CFU by MSA medium suggesting a high amount of Staphylococcus spp. in the clinic environment which can appear through aerosols. A total of 3149 colonies (32.2%) were suggestive of pathogenic staphylococci. Gram coloration, catalase test, colony-mallow growing on chromogenic medium, and coagulase test confirmed the identity of 44 (0.45%) S. aureus isolates. Of these, 35 isolates (79.5%) showed production of beta-lactamase by Cefinase discs and resistance to ampicillin, erythromycin (7 isolates) and tetracycline (1 isolate) suggesting the existence of multiresistant isolates. The evaluation of the oxacillin MIC by Etest assays showed susceptibility patterns suggesting the inexistence of the mecA gene in chromosomal DNA. These results point out to the need of a larger knowledge on the contamination means and propagation of this microorganism into the odontological clinic. PMID:15729470

  14. Clinical isolation and resistance patterns of and superinfection with 10 nosocomial pathogens after treatment with ceftriaxone versus ampicillin-sulbactam.

    Science.gov (United States)

    Carmeli, Y; Castro, J; Eliopoulos, G M; Samore, M H

    2001-01-01

    Isolation of pathogens from clinical cultures and their resistance patterns may be altered by antecedent antibiotic treatment. The objective of this study was to assess the influence of treatment with ceftriaxone versus that with ampicillin-sulbactam on recovery and superinfections with 10 nosocomial pathogens. The study was designed as a historical cohort study, using a propensity score to adjust for confounding by indication and multivariate survival analyses to adjust for other confounding. Two thousand four hundred forty-five patients were treated with ampicillin-sulbactam, and 1, 308 were treated with ceftriaxone. The study analyzed two outcomes: (i) recovery of pathogens from clinical cultures and (ii) microbiologically documented infections. Data were obtained from administrative, pharmacy, clinical, and laboratory databases and by chart extraction. Following treatment, new isolation of at least 1 of the 10 target pathogens occurred for 244 patients. After adjustment, more infections occurred in the ampicillin-sulbactam group (hazard ratio [HR], 1.55; P = 0.009). This was observed with all gram-negative rods combined (HR, 3.6; P ceftriaxone group (3.8% versus 5%; HR, 1.6; P = 0. 015). All the Escherichia coli and Klebsiella spp. isolates were susceptible to ceftriaxone, but half were resistant to ampicillin-sulbactam. The prevalence of oxacillin resistance among Staphylococcus aureus isolates was higher in the ceftriaxone group (63% versus 31%; odds ratio, 3.8; P = 0.08). Differences in the rates of superinfections and the likely causative organisms following treatment with ceftriaxone or ampicillin-sulbactam were evident. This may guide clinicians in empirical choices of antibiotics to treat superinfection. PMID:11120977

  15. The molecular changing mechanism of Ampicillin-Sulbactam resistant Staphylococcus aureus towards Methicillin resistant Staphylococcus aureus

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    Mieke Hemiawati Satari

    2005-12-01

    Full Text Available The aim of this study was to determine the molecular changing of S.aureus, which is resistant to Ampicillin-Sulbactam and then become resistant to Methicillin as a result of improper dosage. The study was conducted by isolating Ampicillin-Sulbactam resistant and Methicillin Resistant S.aureus (MRSA, afterwards an amplification process was performed by PCR (Polymerase Chain Reaction. to isolate the betalactamase enzyme regulator and PBP 2a genes. The result of this research showed that there were a deletion of few amino acids from the regulator gene, and a suspicion that the DNA sequence had been substituted from PBP 2 gene into PBP 2a (gen mec. This process had formed MRSA.

  16. Effect of Ampicillin, Streptomycin, Penicillin and Tetracycline on Metal Resistant and Non-Resistant Staphylococcus aureus

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    Dagmar Chudobova

    2014-03-01

    Full Text Available There is an arising and concerning issue in the field of bacterial resistance, which is confirmed by the number of deaths associated with drug-resistant bacterial infections. The aim of this study was to compare the effects of antibiotics on Staphylococcus aureus non-resistant strain and strains resistant to cadmium or lead ions. Metal resistant strains were created by the gradual addition of 2 mM solution of metal ions (cadmium or lead to the S. aureus culture. An increasing antimicrobial effect of ampicillin, streptomycin, penicillin and tetracycline (0, 10, 25, 50, 75, 150, 225 and 300 µM on the resistant strains was observed using a method of growth curves. A significant growth inhibition (compared to control of cadmium resistant cells was observed in the presence of all the four different antibiotics. On the other hand, the addition of streptomycin and ampicillin did not inhibit the growth of lead resistant strain. Other antibiotics were still toxic to the bacterial cells. Significant differences in the morphology of cell walls were indicated by changes in the cell shape. Our data show that the presence of metal ions in the urban environment may contribute to the development of bacterial strain resistance to other substances including antibiotics, which would have an impact on public health.

  17. Effect of Ampicillin, Streptomycin, Penicillin and Tetracycline on Metal Resistant and Non-Resistant Staphylococcus aureus

    Science.gov (United States)

    Chudobova, Dagmar; Dostalova, Simona; Blazkova, Iva; Michalek, Petr; Ruttkay-Nedecky, Branislav; Sklenar, Matej; Nejdl, Lukas; Kudr, Jiri; Gumulec, Jaromir; Tmejova, Katerina; Konecna, Marie; Vaculovicova, Marketa; Hynek, David; Masarik, Michal; Kynicky, Jindrich; Kizek, Rene; Adam, Vojtech

    2014-01-01

    There is an arising and concerning issue in the field of bacterial resistance, which is confirmed by the number of deaths associated with drug-resistant bacterial infections. The aim of this study was to compare the effects of antibiotics on Staphylococcus aureus non-resistant strain and strains resistant to cadmium or lead ions. Metal resistant strains were created by the gradual addition of 2 mM solution of metal ions (cadmium or lead) to the S. aureus culture. An increasing antimicrobial effect of ampicillin, streptomycin, penicillin and tetracycline (0, 10, 25, 50, 75, 150, 225 and 300 µM) on the resistant strains was observed using a method of growth curves. A significant growth inhibition (compared to control) of cadmium resistant cells was observed in the presence of all the four different antibiotics. On the other hand, the addition of streptomycin and ampicillin did not inhibit the growth of lead resistant strain. Other antibiotics were still toxic to the bacterial cells. Significant differences in the morphology of cell walls were indicated by changes in the cell shape. Our data show that the presence of metal ions in the urban environment may contribute to the development of bacterial strain resistance to other substances including antibiotics, which would have an impact on public health. PMID:24651395

  18. Association between Antimicrobial Consumption and Resistance in Escherichia coli▿

    OpenAIRE

    Bergman, Miika; Nyberg, Solja T; Huovinen, Pentti; Paakkari, Pirkko; Hakanen, Antti J.

    2008-01-01

    During a 9-year study period from 1997 through 2005, the association between antimicrobial resistance rates in Escherichia coli and outpatient antimicrobial consumption was investigated in 20 hospital districts in Finland. A total of 754,293 E. coli isolates, mainly from urine samples, were tested for antimicrobial resistance in 26 clinical microbiology laboratories. The following antimicrobials were studied: ampicillin, amoxicillin-clavulanate, cephalosporins, fluoroquinolones, trimethoprim,...

  19. Use of ampicillin-sulbactam for treatment of experimental meningitis caused by a beta-lactamase-producing strain of Escherichia coli K-1.

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    Guerra-Romero, L; Kennedy, S L; Fournier, M A; Tureen, J H; Täuber, M G

    1991-01-01

    We evaluated the pharmacokinetics and therapeutic efficacy of ampicillin combined with sulbactam in a rabbit model of meningitis due to a beta-lactamase-producing strain of Escherichia coli K-1. Ceftriaxone was used as a comparison drug. The MIC and MBC were 32 and greater than 64 micrograms/ml (ampicillin), greater than 256 and greater than 256 micrograms/ml (sulbactam), 2.0 and 4.0 micrograms/ml (ampicillin-sulbactam [2:1 ratio, ampicillin concentration]) and 0.125 and 0.25 micrograms/ml (c...

  20. Physical size of the donor locus and transmission of Haemophilus influenzae ampicillin resistance genes by deoxyribonucleic acid-mediated transformation

    International Nuclear Information System (INIS)

    The properties of donor deoxyribonucleic acid (DNA) from three clinical isolates and its ability to mediate the transformation of competent Rd strains to ampicillin resistance were examined. A quantitative technique for determining the resistance of individual Haemophilus influenzae cells to ampicillin was developed. When this technique was used, sensitive cells failed to tolerate levels of ampicillin greater than 0.1 to 0.2 μg/ml, whereas three resistant type b β-lactamase-producing strains could form colonies 1- to 3-μg/ml levels of the antibiotic. DNA extracted from the resistant strains elicited transformation of the auxotrophic genes in a multiply auxotrophic Rd strain. For two of the donors, transformation to ampicillin resistance occurred after the uptake of a single DNA molecule approximately 104-fold less frequently than transformation of auxotrophic loci and was not observed to occur at all with the third. The frequency of transformation to ampicillin resistance was two- to fivefold higher in strain BC200 (Okinaka and Barnhart, 1974), which was cured of a defective prophage. All three clinical ampicillin-resistant strains were poor recipients, but the presence of the ampicillin resistant genes in strain BC200 did not reduce its competence

  1. Efficacy of Ampicillin plus Arbekacin in Experimental Rabbit Endocarditis Caused by an Enterococcus faecalis Strain with High-Level Gentamicin Resistance

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    Kak, Vivek; Donabedian, Susan M.; Zervos, Marcus J.; Kariyama, Reiko; Kumon,Hiromi; Chow, Joseph W.

    2000-01-01

    Enterococcus faecalis LC40 is an ampicillin-susceptible clinical isolate with high-level gentamicin resistance due to the aac(6′)-Ie-aph(2")-Ia aminoglycoside resistance gene. The combination of ampicillin plus arbekacin reduced mean bacterial vegetation counts significantly more than ampicillin alone or ampicillin plus gentamicin in a rabbit model of aortic-valve endocarditis caused by E. faecalis LC40.

  2. Antimicrobial Resistance of Escherichia fergusonii Isolated from Broiler Chickens.

    Science.gov (United States)

    Simmons, Karen; Islam, M Rashedul; Rempel, Heidi; Block, Glenn; Topp, Edward; Diarra, Moussa S

    2016-06-01

    The objective of this study was to investigate the antibiotic resistance of Escherichia fergusonii isolated from commercial broiler chicken farms. A total of 245 isolates from cloacal and cecal samples of 28- to 36-day-old chickens were collected from 32 farms. Isolates were identified using PCR, and their susceptibility to 16 antibiotics was determined by disk diffusion assay. All isolates were susceptible to meropenem, amikacin, and ciprofloxacin. The most common resistances were against ampicillin (75.1%), streptomycin (62.9%), and tetracycline (57.1%). Of the 184 ampicillin-resistant isolates, 127 were investigated using a DNA microarray carrying 75 probes for antibiotic resistance genetic determinants. Of these 127 isolates, the β-lactamase blaCMY2, blaTEM, blaACT, blaSHV, and blaCTX-M-15 genes were detected in 120 (94.5%), 31 (24.4%), 8 (6.3%), 6 (4.7%), and 4 (3.2%) isolates, respectively. Other detected genes included those conferring resistance to aminoglycosides (aadA1, strA, strB), trimethoprims (dfrV, dfrA1), tetracyclines (tetA, tetB, tetC, tetE), and sulfonamides (sul1, sul2). Class 1 integron was found in 35 (27.6%) of the ampicillin-resistant isolates. However, our data showed that the tested E. fergusonii did not carry any carbapenemase blaOXA genes. Pulsed-field gel electrophoresis revealed that the selected ampicillin-resistant E. fergusonii isolates were genetically diverse. The present study indicates that the monitoring of antimicrobial-resistant bacteria should include enteric bacteria such as E. fergusonii, which could be a reservoir of antibiotic resistance genes. The detection of isolates harboring extended-spectrum β-lactamase genes, particularly blaCTX-M-15, in this work suggests that further investigations on the occurrence of such genes in broilers are warranted. PMID:27296596

  3. Reversal of Ampicillin Resistance in MRSA via Inhibition of Penicillin-Binding Protein 2a by Acalypha wilkesiana

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    Carolina Santiago

    2014-01-01

    Full Text Available The inhibitory activity of a semipure fraction from the plant, Acalypha wilkesiana assigned as 9EA-FC-B, alone and in combination with ampicillin, was studied against methicillin-resistant Staphylococcus aureus (MRSA. In addition, effects of the combination treatment on PBP2a expression were investigated. Microdilution assay was used to determine the minimal inhibitory concentrations (MIC. Synergistic effects of 9EA-FC-B with ampicillin were determined using the fractional inhibitory concentration (FIC index and kinetic growth curve assay. Western blot experiments were carried out to study the PBP2a expression in treated MRSA cultures. The results showed a synergistic effect between ampicillin and 9EA-FC-B treatment with the lowest FIC index of 0.19 (synergism ≤ 0.5. The presence of 9EA-FC-B reduced the MIC of ampicillin from 50 to 1.56 μg mL−1. When ampicillin and 9EA-FC-B were combined at subinhibitory level, the kinetic growth curves were suppressed. The antibacterial effect of 9EA-FC-B and ampicillin was shown to be synergistic. The synergism is due the ability of 9EA-FC-B to suppress the activity of PBP2a, thus restoring the susceptibility of MRSA to ampicillin. Corilagin was postulated to be the constituent responsible for the synergistic activity showed by 9EA-FC-B.

  4. Antimicrobial resistance among Escherichia coli that cause childhood community-acquired urinary tract infections in Northern Italy

    OpenAIRE

    Caracciolo Alessandra; Bettinelli Alberto; Bonato Claudio; Isimbaldi Clementina; Tagliabue Alessandro; Longoni Laura; Bianchetti Mario G

    2011-01-01

    Abstracts Background Resistance rate of Escherichia coli against antimicrobials that are commonly prescribed in pediatric urinary tract infections is currently a matter of concern. Methods The antimicrobial susceptibility patterns of uropathogenic Escherichia coli strains to the common antibimcrobials ampicillin, cotrimoxazole, coamoxyclav, ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin were determined in 177 children aged from 2 to 36 months. They presented with their first symptom...

  5. Microarray Evaluation of Antimicrobial Resistance and Virulence of Escherichia coli Isolates from Portuguese Poultry

    OpenAIRE

    Nuno Mendonça; Rui Figueiredo; Catarina Mendes; Card, Roderick M.; Anjum, Muna F.; Gabriela Jorge da Silva

    2016-01-01

    The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70%) and ampicillin (63%). Extended-spectrum beta-lactamase (ESBL) phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA m...

  6. Antibiotic Resistance in Diarrheagenic Escherichia coli and Shigella Strains Isolated from Children in Hanoi, Vietnam

    OpenAIRE

    Nguyen, Trung Vu; Le Van, Phung; Le, Chinh Huy; Weintraub, Andrej

    2005-01-01

    The MICs for 162 diarrheagenic Escherichia coli strains and 28 Shigella strains were determined on the basis of NCCLS guidelines. More than 75% of the strains were resistant to ampicillin, chloramphenicol (53.6% of Shigella strains), and trimethoprim-sulfamethoxazole. Multiresistance was detected in 89.5% of E. coli strains and 78.6% of Shigella strains.

  7. Fleroxacin resistance in Escherichia coli.

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    Chapman, J S; Bertasso, A; Georgopapadakou, N H

    1989-01-01

    Spontaneous fleroxacin-resistant mutants of Escherichia coli K-12 were isolated at a frequency of 10(-10) to 10(-11) mutants per CFU plated. All mutants exhibited quinolone-resistant replicative DNA biosynthesis, and 4 of 11 mutants also had decreased amounts of OmpF or OmpC porin. None of the mutants had changes solely in porin proteins.

  8. Association between antimicrobial consumption and resistance in Escherichia coli.

    Science.gov (United States)

    Bergman, Miika; Nyberg, Solja T; Huovinen, Pentti; Paakkari, Pirkko; Hakanen, Antti J

    2009-03-01

    During a 9-year study period from 1997 through 2005, the association between antimicrobial resistance rates in Escherichia coli and outpatient antimicrobial consumption was investigated in 20 hospital districts in Finland. A total of 754,293 E. coli isolates, mainly from urine samples, were tested for antimicrobial resistance in 26 clinical microbiology laboratories. The following antimicrobials were studied: ampicillin, amoxicillin-clavulanate, cephalosporins, fluoroquinolones, trimethoprim, trimethoprim-sulfamethoxazole, pivmecillinam, and nitrofurantoin. We applied a protocol used in earlier studies in which the level of antimicrobial consumption over 1 year was compared with the level of resistance in the next year. Statistically significant associations were found for nitrofurantoin use versus nitrofurantoin resistance (P < 0.0001), cephalosporin use versus nitrofurantoin resistance (P = 0.0293), amoxicillin use versus fluoroquinolone resistance (P = 0.0031), and fluoroquinolone use versus ampicillin resistance (P = 0.0046). Interestingly, we found only a few associations between resistance and antimicrobial consumption. The majority of the associations studied were not significant, including the association between fluoroquinolone use and fluoroquinolone resistance. PMID:19104012

  9. Radiation sensitivity of Salmonella isolates relative to resistance to ampicillin, chloramphenicol or gentamicin

    International Nuclear Information System (INIS)

    Antibiotic resistance of inoculated bacteria is a commonly used selective marker. Bacteria resistant to the antibiotic nalidixic acid have been shown to have an increased sensitivity to irradiation. The purpose of this research was to screen a collection of Salmonella isolates for antibiotic resistance and determine the association, if any, of antibiotic resistance with radiation sensitivity. Twenty-four clinical isolates of Salmonella were screened for native resistance to multiple concentrations of ampicillin (Amp), chloramphenicol (Chl), or gentamicin (Gm). Test concentrations were chosen based on established clinical minimum inhibitory concentration (MIC) levels, and isolates were classified as either sensitive or resistant based on their ability to grow at or above the MIC. Salmonella cultures were grown overnight at (37 oC) in antibiotic-amended tryptic soy broth (TSB). Native resistance to Gm was observed with each of the 24 isolates (100%). Eight isolates (33%) were shown to be resistant to Amp, while seven isolates (29%) were shown to be resistant to Chl. In separate experiments, Salmonella cultures were grown overnight (37 oC) in TSB, centrifuged, and the cell pellets were re-suspended in phosphate buffer. The samples were then gamma irradiated at doses up to 1.0 kGy. The D 10 values (the ionizing radiation dose required to reduce the viable number of microorganisms by 90%) were determined for the 24 isolates and they ranged from 0.181 to 0.359 kGy. No correlation was found between the D 10 value of the isolate and its sensitivity or resistance to each of the three antibiotics. Resistance to Amp or Chl is suggested as appropriate resistance marker for Salmonella test strains to be used in studies of irradiation

  10. Use of ampicillin-sulbactam for treatment of experimental meningitis caused by a beta-lactamase-producing strain of Escherichia coli K-1.

    Science.gov (United States)

    Guerra-Romero, L; Kennedy, S L; Fournier, M A; Tureen, J H; Täuber, M G

    1991-10-01

    We evaluated the pharmacokinetics and therapeutic efficacy of ampicillin combined with sulbactam in a rabbit model of meningitis due to a beta-lactamase-producing strain of Escherichia coli K-1. Ceftriaxone was used as a comparison drug. The MIC and MBC were 32 and greater than 64 micrograms/ml (ampicillin), greater than 256 and greater than 256 micrograms/ml (sulbactam), 2.0 and 4.0 micrograms/ml (ampicillin-sulbactam [2:1 ratio, ampicillin concentration]) and 0.125 and 0.25 micrograms/ml (ceftriaxone). All antibiotics were given by intravenous bolus injection in a number of dosing regimens. Ampicillin and sulbactam achieved high concentrations in cerebrospinal fluid (CSF) with higher dose regimens, but only moderate bactericidal activity compared with that of ceftriaxone was obtained. CSF bacterial titers were reduced by 0.6 +/- 0.3 log10 CFU/ml/h with the highest ampicillin-sulbactam dose used (500 and 500 mg/kg of body weight, two doses). This was similar to the bactericidal activity achieved by low-dose ceftriaxone (10 mg/kg), while a higher ceftriaxone dose (100 mg/kg) produced a significant increase in bactericidal activity (1.1 +/- 0.4 log10 CFU/ml/h). It appears that ampicillin-sulbactam, despite favorable CSF pharmacokinetics in animals with meningitis, may be of limited value in the treatment of difficult-to-treat beta-lactamase-producing bacteria, against which the combination shows only moderate in vitro activity. PMID:1759824

  11. Ampicillin-resistant Enterococcus faecium clonal complex 17 is widespread in healthy dogs: anthropozoonosis or zooanthroponosis?

    DEFF Research Database (Denmark)

    Damborg, Peter Panduro; Williams, Nicola J; Willems, Rob;

    2008-01-01

    Objectives: An increase in nosocomial infections caused by ampicillin-resistant Enterococcus faecium (AREfm) has been recently observed in some European countries. Based on multilocus sequence typing (MLST), most hospital AREfm isolates belong to one distinct genogroup, clonal complex 17 (CC17). In...

  12. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014)

    OpenAIRE

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-01-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin...

  13. Role of Nutrient Limitation and Stationary-Phase Existence in Klebsiella pneumoniae Biofilm Resistance to Ampicillin and Ciprofloxacin

    OpenAIRE

    Anderl, Jeff N.; Zahller, Jeff; Roe, Frank; Stewart, Philip S.

    2003-01-01

    Biofilms formed by Klebsiella pneumoniae resisted killing during prolonged exposure to ampicillin or ciprofloxacin even though these agents have been shown to penetrate bacterial aggregates. Bacteria dispersed from biofilms into medium quickly regained most of their susceptibility. Experiments with free-floating bacteria showed that stationary-phase bacteria were protected from killing by either antibiotic, especially when the test was performed in medium lacking carbon and nitrogen sources. ...

  14. Clinical Isolation and Resistance Patterns of and Superinfection with 10 Nosocomial Pathogens after Treatment with Ceftriaxone versus Ampicillin-Sulbactam

    OpenAIRE

    Carmeli, Yehuda; Castro, Julio; Eliopoulos, George M.; Samore, Matthew H.

    2001-01-01

    Isolation of pathogens from clinical cultures and their resistance patterns may be altered by antecedent antibiotic treatment. The objective of this study was to assess the influence of treatment with ceftriaxone versus that with ampicillin-sulbactam on recovery and superinfections with 10 nosocomial pathogens. The study was designed as a historical cohort study, using a propensity score to adjust for confounding by indication and multivariate survival analyses to adjust for other confounding...

  15. RESISTANCE PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGHE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-02-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests.65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics asfeed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials.

  16. ANTIMICROBIAL RESISTANT PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-12-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests. 65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics as feed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials

  17. Ampicillin Injection

    Science.gov (United States)

    ... injection is in a class of medications called penicillins. It works by killing bacteria.Antibiotics such as ... and pharmacist if you are allergic to ampicillin; penicillins; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin (Ancef, ...

  18. Prevalence of antimicrobial resistance and resistance genes in faecal Escherichia coli isolates recovered from healthy pets.

    Science.gov (United States)

    Costa, Daniela; Poeta, Patricia; Sáenz, Yolanda; Coelho, Ana Cláudia; Matos, Manuela; Vinué, Laura; Rodrigues, Jorge; Torres, Carmen

    2008-02-01

    Faecal samples of healthy dogs (n=39) and cats (n=36) obtained in Northern Portugal were seeded on Levine agar plates, and two Escherichia coli isolates per sample were recovered (78 of dogs and 66 of cats). The susceptibility to 16 antimicrobial agents was tested in this series of 144 E. coli isolates. Almost 20% of them showed tetracycline resistance and 12 and 15% presented ampicillin or streptomycin resistance, respectively. The percentage of resistance to the other antimicrobial agents was in all cases below 4%, and no resistant isolates were detected for ceftazidime, imipenem, cefoxitin or amikacin. Two isolates (from one dog) showed cefotaxime-resistance and harboured both the CTX-M-1 and OXA-30 beta-lactamases. A bla(TEM) gene was detected in 12 of 17 ampicillin-resistant isolates, the aac(3)-II gene in the three gentamicin-resistant isolates, aadA in 7 of 22 streptomycin-resistant isolates, and tet(A) and/or tet(B) gene in all 28 tetracycline-resistant isolates. The gene encoding class 1 integrase was detected in six E. coli isolates, including the four trimethoprim-sulfamethoxazole-resistant isolates and those two harbouring CTX-M-1 and OXA-30 beta-lactamases; different gene cassette arrangements were identified: dfrA1+aadA1 (two isolates), dfrA12+orfF+aadA2 (two isolates) and bla(OXA30)+aadA1 (two isolates). One amino acid change in GyrA protein (Ser83Leu or Asp87Tyr) was detected in four nalidixic acid-resistant and ciprofloxacin-susceptible isolates and two amino acid changes in GyrA (Ser83Leu+Asp87Asn) and one in ParC (Ser80Ile) were identified in one nalidixic acid- and ciprofloxacin-resistant isolate. Faecal E. coli isolates of healthy pets could be a reservoir of antimicrobial resistance genes. PMID:17870255

  19. In vitro and in vivo synergism between amoxicillin and clavulanic acid against ampicillin-resistant Haemophilus influenzae type b.

    OpenAIRE

    Yogev, R; Melick, C; Kabat, W J

    1981-01-01

    Eight strans of ampicillin-resistant beta-lactamase-producing Haemophilus influenzae type b were studied in vitro for synergy between amoxicillin and clavulanic acid. The minimal inhibitory concentrations for amoxicillin alone were 6.25 to 12.5 microgram/ml, and for clavulanic acid alone they were 12.5 to 25 microgram/ml. However, seven of eight strains were inhibited by a combination of 0.36 microgram of amoxicillin and 0.36 microgram of clavulanic acid per ml. Infant rat models of bacteremi...

  20. Heterogeneity among Virulence and Antimicrobial Resistance Gene Profiles of Extraintestinal Escherichia coli Isolates of Animal and Human Origin

    OpenAIRE

    Maynard, Christine; Bekal, Sadjia; Sanschagrin, François; Levesque, Roger C.; Brousseau, Roland; Masson, Luke; Larivière, Serge; Harel, Josée

    2004-01-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) isolates collected from different infected animals and from human patients with extraintestinal infections in 2001 were characterized for their phenotypic and genotypic antimicrobial resistance profiles, genotypes, and key virulence factors. Among the 10 antimicrobial agents tested, resistance to ampicillin, tetracycline, and sulfonamides was most frequent. Multiresistant strains were found in both the animal and the human groups of isolates...

  1. Profiling of antimicrobial resistance and plasmid replicon types in β-lactamase producing Escherichia coli isolated from Korean beef cattle

    OpenAIRE

    Shin, Seung Won; Jung, Myunghwan; Shin, Min-Kyung; Yoo, Han Sang

    2015-01-01

    In this study, 78 isolates of Escherichia coli isolated from Korean beef cattle farms were investigated for the production of extended-spectrum β-lactamase (ESBL) and/or AmpC β-lactamase. In the disc diffusion test with ampicillin, amoxicillin, cephalothin, ceftiofur, cefotaxime, ceftazidime, and cefoxitin, 38.5% of the isolates showed resistance to all of ampicillin, amoxicillin, and cephalothin. The double disc synergy method revealed that none of the isolates produced ESBL or AmpC β-lactam...

  2. Antimicrobial resistance in community and nosocomial Escherichia coli urinary tract isolates, London 2005 – 2006

    Directory of Open Access Journals (Sweden)

    Wareham David W

    2008-06-01

    Full Text Available Abstract Background Escherichia coli is the commonest cause of community and nosocomial urinary tract infection (UTI. Antibiotic treatment is usually empirical relying on susceptibility data from local surveillance studies. We therefore set out to determine levels of resistance to 8 commonly used antimicrobial agents amongst all urinary isolates obtained over a 12 month period. Methods Antimicrobial susceptibility to ampicillin, amoxicillin/clavulanate, cefalexin, ciprofloxacin, gentamicin, nitrofurantoin, trimethoprim and cefpodoxime was determined for 11,865 E. coli urinary isolates obtained from community and hospitalised patients in East London. Results Nitrofurantoin was the most active agent (94% susceptible, followed by gentamicin and cefpodoxime. High rates of resistance to ampicillin (55% and trimethoprim (40%, often in combination were observed in both sets of isolates. Although isolates exhibiting resistance to multiple drug classes were rare, resistance to cefpodoxime, indicative of Extended spectrum β-lactamase production, was observed in 5.7% of community and 21.6% of nosocomial isolates. Conclusion With the exception of nitrofurantoin, resistance to agents commonly used as empirical oral treatments for UTI was extremely high. Levels of resistance to trimethoprim and ampicillin render them unsuitable for empirical use. Continued surveillance and investigation of other oral agents for treatment of UTI in the community is required.

  3. Characterization of Hospital-Associated Lineages of Ampicillin-Resistant Enterococcus faecium from Clinical Cases in Dogs and Humans

    Directory of Open Access Journals (Sweden)

    MarieArchambault

    2013-08-01

    Full Text Available Ampicillin-resistant Enterococcus faecium (ARE has rapidly emerged worldwide and is one of the most important nosocomial pathogens. However, very few reports are available on ARE isolates from canine clinical cases. The objective of this study was to characterize ARE strains of canine clinical origin from a veterinary teaching hospital in Canada and to compare them with human strains. Ten ARE strains from dogs and humans were characterized by multilocus sequence typing (MLST, pulsed field gel electrophoresis (PFGE, antibiotic susceptibility and biofilm activities, presence of rep-families, CRISPR-cas and putative virulence genes. All ARE strains (n = 10 were resistant to ciprofloxacin and lincomycin. Resistances to tetracycline (n = 6, macrolides (n = 6, and to high concentrations of gentamicin, kanamycin and streptomycin (n = 5 were also observed. Canine ARE isolates were found to be susceptible to vancomycin whereas resistance to this antibiotic was observed in human strains. Ampicillin resistance was linked to PBP5 showing mutations at 25 amino acid positions. Fluoroquinolone resistance was attributable to ParC, GyrA, and GyrB mutations. Data demonstrated that all canine ARE were acm (collagen binding protein-positive and that most harbored the efaAfm gene, encoding for a cell wall adhesin. Biofilm formation was observed in two human strains but not in canine strains. Two to five rep-families were observed per strain but no CRISPR sequences were found. A total of six STs (1, 18, 65, 202, 205, and 803 were found with one belonging to a new ST (ST803. These STs were identical or closely related to human hospital-associated lineages. This report describes for the first time the characterization of canine ARE hospital-associated strains in Canada and also supports the importance of prudent antibiotic use in veterinary medicine to avoid zoonotic spread of canine ARE.

  4. Characterization of hospital-associated lineages of ampicillin-resistant Enterococcus faecium from clinical cases in dogs and humans.

    Science.gov (United States)

    Tremblay, Cindy-Love; Charlebois, Audrey; Masson, Luke; Archambault, Marie

    2013-01-01

    Ampicillin-resistant Enterococcus faecium (ARE) has rapidly emerged worldwide and is one of the most important nosocomial pathogens. However, very few reports are available on ARE isolates from canine clinical cases. The objective of this study was to characterize ARE strains of canine clinical origin from a veterinary teaching hospital in Canada and to compare them with human strains. Ten ARE strains from dogs and humans were characterized by multilocus sequence typing (MLST), pulsed field gel electrophoresis (PFGE), antibiotic susceptibility and biofilm activities, presence of rep-families, CRISPR-cas and putative virulence genes. All ARE strains (n = 10) were resistant to ciprofloxacin and lincomycin. Resistances to tetracycline (n = 6), macrolides (n = 6), and to high concentrations of gentamicin, kanamycin and streptomycin (n = 5) were also observed. Canine ARE isolates were found to be susceptible to vancomycin whereas resistance to this antibiotic was observed in human strains. Ampicillin resistance was linked to PBP5 showing mutations at 25 amino acid positions. Fluoroquinolone resistance was attributable to ParC, GyrA, and GyrB mutations. Data demonstrated that all canine ARE were acm (collagen binding protein)-positive and that most harbored the efaAfm gene, encoding for a cell wall adhesin. Biofilm formation was observed in two human strains but not in canine strains. Two to five rep-families were observed per strain but no CRISPR sequences were found. A total of six STs (1, 18, 65, 202, 205, and 803) were found with one belonging to a new ST (ST803). These STs were identical or closely related to human hospital-associated lineages. This report describes for the first time the characterization of canine ARE hospital-associated strains in Canada and also supports the importance of prudent antibiotic use in veterinary medicine to avoid zoonotic spread of canine ARE. PMID:23986753

  5. Evaluation of Eight Different Cephalosporins for Detection of Cephalosporin Resistance in Salmonella enterica and Escherichia coli

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Hasman, Henrik; Veldman, K; Mevius, D

    2010-01-01

    This study evaluates the efficacy of eight different cephalosporins for detection of cephalosporin resistance mediated by extended spectrum beta-lactamases (ESBL) and plasmidic AmpC beta-lactamases in Salmonella and Escherichia coli. A total of 138 E. coli and 86 Salmonella isolates with known beta...... cephalosporin-susceptible, 56 ESBL isolates and 19 isolates with plasmidic AmpC, as well as 10 ampC hyper-producing E. coli. The minimum inhibitory concentration distributions and zone inhibitions varied with the tested compound. Ampicillin-resistant isolates showed reduced susceptibility to the cephalosporins...... compared to ampicillin-susceptible isolates. Cefoperazone, cefquinome, and cefuroxime were not useful in detecting isolates with ESBL or plasmidic AmpC. The best substances for detection were cefotaxime, cefpodoxime, and ceftriaxone, whereas ceftazidime and ceftiofur were not as efficient. Ceftriaxone may...

  6. Antibiotic Resistance of Escherichia Coli Isolated From Poultry and Poultry Environment of Bangladesh

    Directory of Open Access Journals (Sweden)

    Muhammad A. Akond

    2009-01-01

    Full Text Available Problem statement: Increased emergence in microbial resistance to antibiotics is a growing problem in Bangladesh, a tropical country with a large agrarian population having limited medical facilities. Wide spread use of antimicrobials in poultry farming here is a concern of multi-drug microbial resistance development that can potentially be transmitted to human pathogens even from non-pathogenic carrier strains. Attempt was made to assess drug susceptibility in Escherichia coli from poultry sources of Bangladesh. Approach: Eighty selected strains isolated from poultry sources were thoroughly characterized by standard cultural and biochemical tests followed by final identification using latex agglutination test of polyvalent anti-sera, from which 50 were tested for susceptibility to 13 antibiotics following disk diffusion method. Results: 145 (58%, out of total 250, were found positive for E. coli. 52-88% of tested E. coli strains from poultry sources were found resistant to Penicillin, Ciprofloxacin, Riphampicin, Kanamycin, Streptomycin, Cefixine, Erythromycin, Ampicillin, Tetracycline, and 20% strains showed resistance to both Chloramphenicol and Neomycin. No strains showed resistance to Norfloxacin and Gentamicin. Sensitivity was recorded in case of 60-86% strains to Norfloxacin, Gentamicin, Chloramphenicol, and Neomycin; and 26-36% strains against Tetracycline, Streptomycin, and Ampicillin. Intermediate resistance/ susceptibility to various antibiotics were observed for 12-36% Escherichia coli strains. Both, resistance and susceptibility were exhibited against Chloramphenicol, Ampicillin, Gentamicin, Neomycin, Tetracycline, Streptomycin and Norfloxacin. Multi drug resistance was found in case of 6-10 antibiotics for all strains tested. Conclusion: Further study is required on the role of poultry borne bacteria as vectors in transmitting drug resistance. Attention is to be paid for personnel hygiene in processing and handling of poultry and

  7. Antimicrobial resistance of Escherichia coli isolates from canine urinary tract infections.

    Science.gov (United States)

    Chang, Shao-Kuang; Lo, Dan-Yuan; Wei, Hen-Wei; Kuo, Hung-Chih

    2015-01-01

    This study determined the antimicrobial resistance profiles of Escherichia coli isolates from dogs with a presumptive diagnosis of urinary tract infection (UTI). Urine samples from 201 dogs with UTI diagnosed through clinical examination and urinalysis were processed for isolation of Escherichia coli. Colonies from pure cultures were identified by biochemical reactions (n=114) and were tested for susceptibility to 18 antimicrobials. The two most frequent antimicrobials showing resistance in Urinary E. coli isolates were oxytetracycline and ampicillin. Among the resistant isolates, 17 resistance patterns were observed, with 12 patterns involving multidrug resistance (MDR). Of the 69 tetracycline-resistant E. coli isolates, tet(B) was the predominant resistance determinant and was detected in 50.9% of the isolates, whereas the remaining 25.5% isolates carried the tet(A) determinant. Most ampicillin and/or amoxicillin-resistant E. coli isolates carried blaTEM-1 genes. Class 1 integrons were prevalent (28.9%) and contained previously described gene cassettes that are implicated primarily in resistance to aminoglycosides and trimethoprim (dfrA1, dfrA17-aadA5). Of the 44 quinolone-resistant E. coli isolates, 38 were resistant to nalidixic acid, and 6 were resistant to nalidixic acid, ciprofloxacin and enrofloxacin. Chromosomal point mutations were found in the GyrA (Ser83Leu) and ParC (Ser80Ile) genes. Furthermore, the aminoglycoside resistance gene aacC2, the chloramphenicol resistant gene cmlA and the florfenicol resistant gene floR were also identified. This study revealed an alarming rate of antimicrobial resistance among E. coli isolates from dogs with UTIs. PMID:25720807

  8. Antimicrobial resistance in community and nosocomial Escherichia coli urinary tract isolates, London 2005 – 2006

    OpenAIRE

    Wareham David W.; Krahe Daniel; Bean David C

    2008-01-01

    Abstract Background Escherichia coli is the commonest cause of community and nosocomial urinary tract infection (UTI). Antibiotic treatment is usually empirical relying on susceptibility data from local surveillance studies. We therefore set out to determine levels of resistance to 8 commonly used antimicrobial agents amongst all urinary isolates obtained over a 12 month period. Methods Antimicrobial susceptibility to ampicillin, amoxicillin/clavulanate, cefalexin, ciprofloxacin, gentamicin, ...

  9. High-level Multi-Resistant and Virulent Escherichia coli in Abeokuta, Nigeria.

    Science.gov (United States)

    Akinduti, Paul Akinniyi; Aboderin, Bukola W; Oloyede, Rasaq; Ogiogwa, Joseph I; Motayo, Babatunde O; Ejilude, Oluwaseun

    2016-01-01

    Multi-resistant Escherichia coli (E. coli) strains co-harboring virulence genes is a cause of high morbidity in Abeokuta, Nigeria. This study was designed to determine some virulent factors among enteropathogenic E. coli in Abeokuta, Nigeria. Approximately non-repetitive 102 isolates of E. coli were recovered from clinical samples from two health facilities in Abeokuta. Biotyping using API and antibiotic susceptibility was determined, and eae and flic genes were assayed by PCR. Antibiotic resistance relatedness was performed by DendroUPGMA. Results showed that 48.0% and 52.0 % were intestinal and extra-intestinal E. coli, ampicillin recorded 100% resistance, amoxycilli/clavulanic acid 64.7%, cotrimoxazole 57.8% and 56.8% resistance against cefotaxime, at MIC >16 ug/mL, 100%, 57.8%, and 50% have MIC50 to ampicillin, tetracycline, and ceftazidime, while 74.5% and 48.0% have MIC90 to ampicillin and ceftazidime. Significant rates of 4.9%, 7.8%, and 9.8% flic, eae, and flic/eae genes were found in intestinal isolates, while 2.9%, 2.0%, and 3.9% were found in extra-intestinal (P < 0.05). Two major clades of the resistant isolates reveal significant antibiotic relatedness among intestinal and extra-intestinal isolates, at 54% resistance similarities with very high multi-antibiotic resistance index of 1.0 (MARI). A high rate of undetected virulent E. coli pathotypes with high resistance could trigger unprecedented morbidity and mortality, mostly among children and the elderly. PMID:26263915

  10. 21 CFR 522.90c - Ampicillin sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ampicillin sodium. 522.90c Section 522.90c Food... Ampicillin sodium. (a) Specifications. Each milliliter of aqueous solution constituted from ampicillin sodium.... (including S. equi), Escherichia coli, and Proteus mirabilis, and skin and soft tissue infections...

  11. Occurrence of quinolone- and beta-lactam-resistant Escherichia coli in danish broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne;

    An increased concern for the possible transfer of resistant bacteria or mobile resistance elements from food animals to humans has resulted in rigorous legislation preventing i.e. practical use of fluoroquinolones in the Danish broiler industry (Olesen et al., 2004; Petersen et al., 2006). In...... F. M. Aarestrup. 2004. Prevalence of ß-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark. Micr. Drug Res. 10:334-340. Petersen, A., J. P. Christensen, P. Kuhnert, M. Bisgaard, J. E. Olsen. 2006. Vertical transmission of a fluoroquinolone...

  12. Monitoring and Analysis on Multi Drug Resistance of Escherichia coli from Captive Population Amur Tiger

    Institute of Scientific and Technical Information of China (English)

    Xue; Yuan; Li; Fengyong; Sun; Jing; Cai; Longhui; Wu; Qingming; Zhou; Ming; Huang; Xianguang; Hua; Yuping

    2014-01-01

    In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sensitivity of E. coli isolates to 14 antibiotics was determined by scrip diffusion method. The results indicated that all the isolates varied in drug resistance to different antibiotics; the isolates gave high resistance to ampicillin,with a drug fast rate of 100%; over80% of the isolates were resistant to tetracycline and Paediatric Compound Sulfamethoxazole Tablets(SMZ- TMP),and over 70% of the isolates were sensitive to aztreonam,amoxicillin /potassium clavulanate. Most of the isolates had high sensitive to aztreonam and amoxicillin / clavulanate acid.

  13. Multidrug resistant Escherichia coli strains isolated from urine sample, University of Gondar Hospital, Northwest Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Setegn Eshetie; Fentahun Tarekegn; Gemechu Kumera; Feleke Mekonnen

    2016-01-01

    Objective: To assess multidrug resistant (MDR) Escherichia coli (E. coli) isolates from patients with urinary tract infection. Methods: From February to June 2014, a cross sectional study was conducted among urinary tract infection patients at the University of Gondar Hospital. Culture and disk diffusion method were used for E. coli isolation and to determine the antibiotic susceptibility patterns. Data were entered and analyzed using SPSS version 20. P Results: A total of 112 E. coli isolates were identified and the rate of isolation was higher among female participants (28.7%; P = 0.03). Of the isolates, 104 (92.9%) were MDR E. coli; and the isolates showed high resistance rates towards ampicillin (99%), cotrimoxazole (69%), chloramphenicol (58.7%), gentamycin (56.7%) and ceftazidime (55.8%). However, comparative isolates showed low resistance rates to ciprofloxacin (1%), cefepime (8.7%), and ceftriaxone (11.5%). Moreover, resistance rates of MDR E. coli isolates were significantly higher than non-MDR strains for ceftazidime (55.8% versus 12.5%; P = 0.015), and ampicillin (99% versus 87.5%; P = 0.018). Conclusions: High prevalence of MDR E. coli isolates was observed in this study. Regular monitoring of antibiotic resistance rates is necessarily required to improve and revise empirical antibiotic therapy protocols.

  14. Study of Sensibility and Antimicrobial Resistance in Escherichia coli Isolated from Urinary Tract Infection in Tabriz City

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    Hamed Molaabaszadeh

    2013-09-01

    Full Text Available  Background & Objective: Urinary infection is one of the most prevalent infectious diseases, and Escherichia coli is the most important cause of urinary infections. This study was done with the aim of surveying the amount of susceptibility and resistance among the strains of Escherichia coli isolated from those who referred to the private laboratories in the Iranian city of Tabriz.   Materials & Methods: This survey was done periodically during the first 6 months of the year 2010. Samples were obtained in a sterile manner and were subjected to all necessary pathological tests. Evaluation of antibiotic susceptibility was conducted with disk diffusion standard method, and the results were analyzed.   Results: Totally, 5701 Escherichia coli strains were identified. The highest sensitivity to Imipenem was 90.95%, Nitrofurantoin 85.97%, and Cefotaxime 71.02% and the highest resistance to Ampicillin was 83.95%, Tetracycline 80.97%, and Co-trimoxazole 63.92%.   Conclusion: Our results suggest that the cause of the high resistance of Escherichia coli strains to Ampicillin and Tetracycline could be the consumption of these antibiotics. Therefore, abstaining from overuse of unnecessary antibiotics and production of new-generation and cost-effective antibiotics are recommend. 

  15. Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England

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    Williams Nicola J

    2010-04-01

    Full Text Available Abstract Background Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhibitory concentrations (MIC. PCR amplification was used to detect genes conferring resistance to: ampicillin (TEM and SHV beta-lactamase, chloramphenicol (catI, catII, catIII and cml, tetracycline (tetA, tetB, tetC, tetD, tet E and tetG, and trimethoprim (dfrA1, dfrA9, dfrA12, dfrA13, dfr7, and dfr17. Results The proportion of antibiotic resistant isolates, and multidrug resistant isolates (MDR was significantly higher in hospital samples compared to livery samples (MDR: 48% of hospital isolates; 12% of livery isolates, p dfr, TEM beta-lactamase, tet and cat, conferring resistance to trimethoprim, ampicillin, tetracycline and chloramphenicol, respectively. Within each antimicrobial resistance group, these genes occurred at frequencies of 93% (260/279, 91%, 86.8% and 73.5%, respectively; with 115/296 (38.8% found to be MDR isolates. Conjugation experiments were performed on selected isolates and MDR phenotypes were readily transferred. Conclusions Our findings demonstrate that E. coli of equine faecal origin are commonly resistant to antibiotics used in human and veterinary medicine. Furthermore, our results suggest that most antibiotic resistance observed in equine E. coli is encoded by well-known and well-characterized resistant genes common to E. coli from man and domestic animals. These data support the ongoing concern about antimicrobial resistance, MDR, antimicrobial use in veterinary medicine and the zoonotic risk that horses could potentially pose to

  16. Antibiotic resistance and plasmids carriage among Escherichia coli isolates from chicken meat in Malaysia

    International Nuclear Information System (INIS)

    One hundred and thirty-one Escherichia coli isolates from raw chicken meat were tested for antibiotic susceptibility to twelve antibiotics, namely ampicillin 10μg, cefoparazone 30μg, cephradine 30μg, ciprofloxacin 5μg, chloramphenicol 30μg, enrofloxacin 5μg, erythromycin 15μg, kanamycin 30μg, nalidixic acid 30μg, tetracycline 30μg, trimethoprim 5μg, and vancomycin 30μg. The plasmid isolation was carried out according to the method described by Maniatis et al, with modifications as in the protocol provided by Taq Dye Deoxy Terminator Cycle Sequencing Kit (ABI P/ N 401150). The newly modified method is a mini alkaline-lysis / PGE precipitation procedure and easy to perform on large numbers of samples. The graphical method of relating the logarithm of the molecular weight of a DNA molecule (log C) to its electrophoretic mobility (m) in gels was used to determine the molecular weight of plasmid. Plasmids of known molecular weight from E. coli V517 were used as standards for calibrating the size of plasmid DNA molecules. In this study DNA fragments are referred to as plasmids. In all Escherichia coli isolates resistance to ampicillin (96.2%), cefoperazone (83.3%), cephradine (93.9%), ciprofloxacin (78.0%), chloramphenical (75.6%), enrofloxacin (72.0%), erythromycin (84.0%), kanamycin (50.8%), nalidixic acid (94.7%), tetracycline (90.2%), trimethoprim (94.7%) and vancomycin (100%) was observed (Table I). Plasmid occurrence rates of 81.7% were observed among E. coli isolates from the chicken meat. The number of plasmids ranged from 0 to 8 and the sizes of plasmids ranged from 1.2 MDa to 118.6 MDa. Plasmids were detected in 93.8% of E. coli isolates that were resistant to all 12 antibiotics and in 90.5% of E. coli isolates resistant to 11 antibodies (Table II). Three (2.8%) E. coli isolates harboured 8 plasmids and showed resistant to 12 antibiotics (Table III). The antibiotic resistance among the E. coli isolates in this study was compared and it was found a

  17. Antimicrobial Resistant Pattern of Escherichia Coli Strains Isolated from Pediatric Patients in Jordan

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    Mohammad Alshara

    2011-05-01

    Full Text Available The present study was conducted to investigate antimicrobial resistant pattern of Escherichia coli (E. coli strains isolated from clinical specimens of Jordanian pediatric patients during the period from January to December 2008. A total of 444 E. coli strains were isolated from clinical specimens and tested for their susceptibility to different antimicrobial drugs. Overall, high resistance rate was observed for ampicillin (84%, followed by amoxicillin-clavulanic acid (74.3%, cotrimoxazole (71%, nalidixic acid (47.3%, cephalothin (41%. Lower resistance rates were observed for amikacin (0% followed by Cefotaxime (11%, Ceftriaxone (11.7%, ciprofloxacin (14.5%, Norfloxacin (16.5%, gentamicin (17.3% cephalexin (20.9%, Ceftazidime (22.5%, cefixime (29.6%, and cefaclor (32.8%. Ampicillin, amoxicillin-clavulanic acid and cotrimoxazole were found to be ineffective at in vitro inhibition of the E. coli of pediatric origin. Amikacin was highly effective for E. coli with susceptibility rate of 100%. The majority of E. coli strains were susceptible to third generation cephalosporins and fluoroquinolones.

  18. Molecular detection and antimicrobial resistance of diarrheagenic Escherichia coli strains isolated from diarrheal cases

    International Nuclear Information System (INIS)

    Objective was to identify and classify Iranian isolates of diarrheagenic Escherichia coli (E. coli) on the basis of presence of virulence genes and to determine antibiotic susceptibility of isolated strains. The current cross-sectional study was conducted in 2005 at the Pasteur Institute, Tehran, Iran. One hundred and ninety-three diarrheagenic E. coli isolated from diarrheal patients in different regions of Iran were included in current study. Virulence factors genees for diarrheagenic E. coli were detected by polymerase chain reaction. Of the 193 diarrheagenic E. coli detected by PCR, 86(44.5%) were Shiga toxin-producing E. coli (STEC), 74 (38.4%) enteropathogenic E. coli (EPEC), 19 (9.8%) enteroaggregative E. coli and 14 (7.3%) enterotoxigenic E. coli isolates. Susceptibility to 12 clinically important antimicrobial agents was determined for 193 strains of diarrhheagenic E. coli. A high incidence of resistance to tetracycline (63%), ampicillin (62%), streptomycin (56%), amoxicillin/clavulanic acid (44.5%), trimetoprim/sulphamethoxazole (39.5%) and cephalothin (37%) was observed. The STEC and EPEC strains with high resistance to tetracycline and ampicillin but highly susceptible to quinolones are among the most important causative agent of diarrhea in Iran. This study suggests that antimicrobial resistance is wide spread among E. coli strains colonizing Iranian patients. Guidelines for appropriate use of antibiotics in developing countries require updating. (author)

  19. Determination Pattern of Antibiotic Resistance in Entropathogenic Escherichia coli Strains Isolated from Children with Diarrhea

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    P. Karami

    2012-04-01

    Full Text Available Introduction & Objective: Diarrheal diseases are considered a major health problem, especially in children. Enteropathogenic Escherichia coli (EPEC strains are the common cause of diarrhea in children especially in developing countries. Because of undesirable effects of diarrhea and its interference with children's growth, in some cases antibiotic treatment is recommended. In recent years, resistance toward common and effective antibiotics in the treatment of infectious diseases became one of the most important challenges in medical society, for this purpose, antibiotic sensitivity and resistance of strains in every geographical zone must be determined. So in this study, of antibiotic patterns of these bacteria were examined.Materials & Methods: This cross-sectional study was performed on 192 strains of Enteropathogen Escherichia coli isolated from children who were suffering from diarrhea in 1389-1390 in the microbiology laboratory of Hamadan University of medical sciences. To identify these strains, standard biochemical and serology tests were used. The antibiotic sensitivity test of these isolates was carried out with disc diffusion agar method according to the CLSI standards for 14 different antibiotics disc. Resistance toward 3 or more than 3 classes of antibiotics were defined as multidrug resistance.Results: The result of this study shows EPEC strains had the highest resistance to cefpodoxime (97%, trimethoprim (60.7%, tetracycline (58.4% and ampicillin (45.8%. Multidrug resistance was 68.7 percent. These strains also showed the highest sensitivity against imipenem, ceftriaxone, and ciprofloxacin antibiotics.Conclusion: EPEC strains that were studied with resistance to ampicillin, tetracycline and convenient sensitivity against fluoroquinolones are one of the major factors in children’s diarrhea. A result of this research suggests that antimicrobial resistance in Escherichia coli strains are high and prescribing and antibiotic is not

  20. Emergence of clinical isolates of Escherichia coli producing TEM-1 derivatives or an OXA-1 beta-lactamase conferring resistance to beta-lactamase inhibitors.

    OpenAIRE

    Zhou, X. Y.; Bordon, F; Sirot, D; Kitzis, M D; Gutmann, L

    1994-01-01

    Sixteen Escherichia coli clinical isolates which were resistant to ampicillin and amoxicillin-clavulanate but susceptible to cephalothin were studied. Eight strains showed the presence of a beta-lactamase which comigrates with reference OXA-1 enzyme. The eight other strains produced different TEM-1 derivatives which had in common a higher Km for penicillins and a higher 50% inhibitory concentration for the beta-lactamase inhibitors. By oligotyping and sequencing of PCR products, it was shown ...

  1. Comparison of antimicrobial resistant Escherichia coli in wild and captive Japanese serows.

    Science.gov (United States)

    Kinjo, T; Minamoto, N; Sugiyama, M; Sugiyama, Y

    1992-10-01

    The fecal Escherichia coli isolated from wild Japanese serows living in mountainous areas away from humans and those from captive serows kept in human areas were examined for antimicrobial resistance and the possession of transferable R plasmids. Of 874 E. coli strains isolated from 283 wild serows in 1980-1981, only 11 (1.3%) were resistant to at least one of 6 antimicrobial drugs; ampicillin, streptomycin, tetracycline, chloramphenicol, kanamycin and sulfadimethoxin. Seven (2.5%) individuals were found to carry resistant E. coli. To heighten the isolation frequency of drug-resistant strains, fecal samples of 244 wild serows in 1983-1984 were cultured directly onto drug-supplemented media. Only 12 (4.9%) serows were shown to have drug-resistant E. coli. No transferable R plasmid was detected among a total of 87 resistant strains from wild serows. In contrast, all 33 captive serows except one which was kept only one day after capture, showed resistant E. coli and 20 (60.6%) serows were excreting R plasmid-carrying E. coli. Of 161 drug-resistant strains from captive serows, 50 (31.1%) were found to carry R plasmids. Wild serows seemed to readily change to harbor resistant E. coli almost as soon they were reared in human areas without direct exposure to drugs. These results lead to the conclusion that drug-resistant E. coli can probably be used as microbial indicator for natural environmental pollution. PMID:1420561

  2. Sensitivity of antibiotic resistant and antibiotic susceptible Escherichia coli, Enterococcus and Staphylococcus strains against ozone.

    Science.gov (United States)

    Heß, Stefanie; Gallert, Claudia

    2015-12-01

    Tolerance of antibiotic susceptible and antibiotic resistant Escherichia coli, Enterococcus and Staphylococcus strains from clinical and wastewater samples against ozone was tested to investigate if ozone, a strong oxidant applied for advanced wastewater treatment, will affect the release of antibiotic resistant bacteria into the aquatic environment. For this purpose, the resistance pattern against antibiotics of the mentioned isolates and their survival after exposure to 4 mg/L ozone was determined. Antibiotic resistance (AR) of the isolates was not correlating with higher tolerance against ozone. Except for ampicillin resistant E. coli strains, which showed a trend towards increased resistance, E. coli strains that were also resistant against cotrimoxazol, ciprofloxacin or a combination of the three antibiotics were similarly or less resistant against ozone than antibiotic sensitive strains. Pigment-producing Enterococcus casseliflavus and Staphylococcus aureus seemed to be more resistant against ozone than non-pigmented species of these genera. Furthermore, aggregation or biofilm formation apparently protected bacteria in subsurface layers from inactivation by ozone. The relatively large variance of tolerance against ozone may indicate that resistance to ozone inactivation most probably depends on several factors, where AR, if at all, does not play a major role. PMID:26608763

  3. Fate of classical faecal bacterial markers and ampicillin-resistant bacteria in agricultural soils under Mediterranean climate after urban sludge amendment.

    Science.gov (United States)

    Gondim-Porto, Clarissa; Platero, Leticia; Nadal, Ignacio; Navarro-García, Federico

    2016-09-15

    The use of sewage sludge or biosolids as agricultural amendments may pose environmental and human health risks related to pathogen or antibiotic-resistant microorganism transmission from soils to vegetables or to water through runoff. Since the survival of those microorganisms in amended soils has been poorly studied under Mediterranean climatic conditions, we followed the variation of soil fecal bacterial markers and ampicillin-resistant bacteria for two years with samplings every four months in a split block design with three replica in a crop soil where two different types of biosolids (aerobically or anaerobically digested) at three doses (low, 40; intermediate, 80; and high, 160Mg·ha(-1)) were applied. Low amounts of biosolids produced similar decay rates of coliform populations than in control soil (-0.19 and -0.27log10CFUs·g(-1)drysoilmonth(-1) versus -0.22) while in the case of intermediate and high doses were close to zero and their populations remained 24months later in the range of 4-5log10CFUs·g(-1)ds. Enterococci populations decayed at different rates when using aerobic than anaerobic biosolids although high doses had higher rates than control (-0.09 and -0.13log10CFUs·g(-1)dsmonth(-1) for aerobic and anaerobic, respectively, vs -0.07). At the end of the experiment, counts in high aerobic and low and intermediate anaerobic plots were 1 log10 higher than in control (4.21, 4.03, 4.2 and 3.11log10CFUs·g(-1) ds, respectively). Biosolid application increased the number of Clostridium spores in all plots at least 1 log10 with respect to control with a different dynamic of decay for low and intermediate doses of aerobic and anaerobic sludge. Ampicillin-resistant bacteria increased in amended soils 4months after amendment and remained at least 1 log10 higher 24months later, especially in aerobic and low and intermediate anaerobic plots due to small rates of decay (in the range of -0.001 to -0.008log10CFUs·g(-1)dsmonth(-1) vs -0.016 for control). Aerobic

  4. Echinoderms from Azores islands: an unexpected source of antibiotic resistant Enterococcus spp. and Escherichia coli isolates.

    Science.gov (United States)

    Marinho, Catarina; Silva, Nuno; Pombo, Sofia; Santos, Tiago; Monteiro, Ricardo; Gonçalves, Alexandre; Micael, Joana; Rodrigues, Pedro; Costa, Ana Cristina; Igrejas, Gilberto; Poeta, Patrícia

    2013-04-15

    The prevalence of antibiotic resistance and the implicated mechanisms of resistance were evaluated in Enterococcus spp. and Escherichia coli, isolated from a total of 250 faecal samples of echinoderms collected from Azorean waters (Portugal). A total of 144 enterococci (120 Enterococcus faecium, 14 E. hirae, 8 E. faecalis, 2 E. gallinarum) and 10 E. coli were recovered. High percentages of resistance in enterococci were found for erythromycin, ampicillin, tetracyclin and ciprofloxacin. The erm(A) or erm(B), tet(M) and/or tet(L), vat(D), aac(6')-aph(2″) and aph(3')-IIIa genes were found in isolates resistant to erythromycin, tetracycline, quinupristin/dalfopristin, high-level gentamicin and high-level kanamycin, respectively. Resistance in E. coli isolates was detected for streptomycin, amikacin, tetracycline and tobramycin. The aadA gene was found in streptomycin-resistant isolates and tet(A)+tet(B) genes in tetracycline-resistant isolates. The data recovered are essential to improve knowledge about the dissemination of resistant strains through marine ecosystems and the possible implications involved in transferring these resistances either to other animals or to humans. PMID:23419753

  5. Evaluation of Petrifilm™ Select E. coli Count Plate medium to discriminate antimicrobial resistant Escherichia coli

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    Jensen Lars

    2008-09-01

    Full Text Available Abstract Background Screening and enumeration of antimicrobial resistant Escherichia coli directly from samples is needed to identify emerging resistant clones and obtain quantitative data for risk assessment. Aim of this study was to evaluate the performance of 3M™ Petrifilm™ Select E. coli Count Plate (SEC plate supplemented with antimicrobials to discriminate antimicrobial-resistant and non-resistant E. coli. Method A range of E. coli isolates were tested by agar dilution method comparing the Minimal Inhibitory Concentration (MIC for eight antimicrobials obtained by Mueller-Hinton II agar, MacConkey agar and SEC plates. Kappa statistics was used to assess the levels of agreement when classifying strains as resistant, intermediate or susceptible. Results SEC plate showed that 74% of all strains agreed within ± 1 log2 dilution when comparing MICs with Mueller-Hinton II media. High agreement levels were found for gentamicin, ampicillin, chloramphenicol and cefotaxime, resulting in a kappa value of 0.9 and 100% agreement within ± 1 log2 dilution. Significant variances were observed for oxytetracycline and sulphamethoxazole. Further tests showed that the observed discrepancy in classification of susceptibility to oxytetracycline by the two media could be overcome when a plate-dependent breakpoint of 64 mg/L was used for SEC plates. For sulphamethoxazole, SEC plates provided unacceptably high MICs. Conclusion SEC plates showed good agreement with Mueller-Hinton II agar in MIC studies and can be used to screen and discriminate resistant E. coli for ampicillin, cephalothin, streptomycin, chloramphenicol, cefotaxime and gentamicin using CLSI standardized breakpoints, but not for sulphamethoxazole. SEC plates can also be used to discriminate oxytetracycline-resistant E. coli if a plate-dependent breakpoint value of 64 mg/L is used.

  6. CHARACTERIZATION OF VIRULENCE GENES AND ANTIMICROBIAL RESISTANCE OF LUNG PATHOGENIC ESCHERICHIA COLI ISOLATES IN FOREST MUSK DEER (MOSCHUS BEREZOVSKII).

    Science.gov (United States)

    Luo, Xi; Wang, Peng; Cheng, Jian-guo; Luo, Yan; Dai, Lei; Zhou, Xin; Zou, Li-kou; Li, Bei; Xiao, Jiu-Jin

    2016-06-01

    This study investigated genotypic diversity, 26 virulence genes, and antimicrobial susceptibility of lung pathogenic Escherichia coli (LPEC) isolated from forest musk deer. Associations between virulence factors (VFs) and phylogenetic group, between antimicrobial resistance (AMR) and phylogenetic group, and between AMR and VFs were subsequently assessed. The results showed 30 LPEC isolated were grouped into seven different clusters (A, B, C, D, E, F, and G). The detection rates of crl (90%), kpsMT II (76.67%), mat (76.67%), and ompA (80%) were over 75%. The most frequent types of resistance were to amoxicillin (100%), sulfafurazole (100%), ampicillin (96.67%), and tetracycline (96.67%), with 93.33% (n = 28) of isolates resistant to more than eight types of drugs. There were significant relationships between resistance to cefalotin and the presence of iucD(a) (P < 0.001), papC (P = 0.032), and kpsMT II (P = 0.028); between resistance to chloromycetin and the presence of irp2 (P = 0.004) and vat (P = 0.047); between resistance to nalidixic acid and the presence of crl (P = 0.002) and iucD(a) (P = 0.004); and between resistance to ampicillin/sulbactam and the presence of vat (P = 0.013). These results indicated there could be some association between resistance and VFs, and there is a great need for the prudent use of antimicrobial agents in LPEC. PMID:27468027

  7. Interplay between pathogenicity island carriage, resistance profile and plasmid acquisition in uropathogenic Escherichia coli.

    Science.gov (United States)

    Calhau, Vera; Domingues, Sara; Ribeiro, Graça; Mendonça, Nuno; Da Silva, Gabriela Jorge

    2015-08-01

    This study aimed to characterize the relationship between pathogenicity islands (PAIs), single virulence genes and resistance among uropathogenic Escherichia coli, evaluating the resistance plasmid carriage fitness cost related to PAIs. For 65 urinary E. coli, antimicrobial susceptibility and extended-spectrum β-lactamase production were determined with the Vitek 2 Advanced Expert system. Phylogroup determination, detection of PAIs and virulence genes papAH, papC, sfa/foc, afa/dra, iutA, kpsMII, cnf1, eaeA, hlyA, stx1 and stx2, plasmid replicon typing and screening for plasmidic resistance determinants qnr, aac(6')-Ib-cr, qepA and bla(CTX-M) were carried out by PCR. Conjugation was performed between a donor carrying IncF, IncK and bla(CTX-M-15), and receptors carrying one to six PAIs. The relative fitness of transconjugants was estimated by pairwise competition experiments. PAI IV(536) (68 %), gene iutA (57 %) and resistance to ampicillin were the most prevalent traits. PAI I(536), PAI II(536), PAI III(536) and PAI II(J96) were exclusively associated with susceptibility to amoxicillin/clavulanic acid, cefotaxime, ceftazidime, ciprofloxacin, gentamicin and trimethoprim/sulfamethoxazole, and were more prevalent in strains susceptible to ampicillin and cefalotin. PAI IV(536), PAI II(CFT073) and PAI I(CFT073) were more prevalent among isolates showing resistance to amoxicillin/clavulanic acid, cefalotin, cefotaxime, ceftazidime and gentamicin. An inverse relationship was observed between the number of plasmids and the number of PAIs carried. Transconjugants were obtained for receptors carrying three or fewer PAIs. The mean relative fitness rates of these transconjugants were 0.87 (two PAIs), 1.00 (one PAI) and 1.09 (three PAI). The interplay between resistance, PAI carriage and fitness cost of plasmid acquisition could be considered PAI specific, and not necessarily associated with the number of PAIs. PMID:26293926

  8. Antibiotic residues and drug resistance in human intestinal flora.

    OpenAIRE

    Corpet, D. E.

    1987-01-01

    The effect of residual levels of ampicillin on the drug resistance of fecal flora was studied in human volunteers given 1.5 mg of ampicillin orally per day for 21 days. This treatment failed to have any significant reproducible effect on the number of resistant Escherichia coli in their feces. The effect of continuous administration of small doses of ampicillin, chlortetracycline, or streptomycin in the drinking water was studied in gnotobiotic mice inoculated with a human fecal flora. In thi...

  9. Comparative efficacies of pivmecillinam and ampicillin in acute shigellosis.

    OpenAIRE

    Kabir, I; Rahaman, M. M.; Ahmed, S. M.; Akhter, S Q; Butler, T

    1984-01-01

    The clinical efficacies of pivmecillinam and ampicillin were compared in a randomized double-blind trial in the treatment of acute shigellosis. Of 44 adult male patients, all culture positive for Shigella strains, 22 patients received 400 mg of pivmecillinam and 22 patients received 500 mg of ampicillin every 6 h. Both drugs were administered orally for 5 days. Four patients receiving ampicillin were infected with Shigella strains that were resistant to ampicillin but susceptible to pivmecill...

  10. Fecal carriage of vancomycin- and ampicillin-resistant Enterococci observed in Swedish adult patients with diarrhea but not among healthy subjects.

    Science.gov (United States)

    Olofsson, M B; Pörnull, K J; Karnell, A; Telander, B; Svenungsson, B

    2001-01-01

    During a 1-y prospective study between 1 October 1996 and 30 September 1997, fecal samples from 786 adult patients with diarrhea and 203 healthy control subjects were screened for vancomycin-resistant Enterococci (VRE) and ampicillin-resistant Enterococci (ARE). The carriage rates of VRE and ARE were 0.4% and 6%, respectively among patients and 0% among controls. The 3 VRE isolates were all VanA and were obtained from patients who had been abroad (Thailand, Spain, France) within the previous 3 months. Thirteen of the 45 patients with ARE (29%) had been abroad within 2 weeks of the onset of diarrhea. These findings suggest a potential risk of introduction of antibiotic-resistant Enterococci in Swedish hospitals by patients receiving treatment for diarrhea after traveling abroad. PMID:11669222

  11. Molecular characterization of antimicrobial resistance in enterococci and Escherichia coli isolates from European wild rabbit (Oryctolagus cuniculus).

    Science.gov (United States)

    Silva, Nuno; Igrejas, Gilberto; Figueiredo, Nicholas; Gonçalves, Alexandre; Radhouani, Hajer; Rodrigues, Jorge; Poeta, Patrícia

    2010-09-15

    A total of 44 Escherichia coli and 64 enterococci recovered from 77 intestinal samples of wild European rabbits in Portugal were analyzed for resistance to antimicrobial agents. Resistance in E. coli isolates was observed for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, gentamicin, tobramycin, nalidixic acid, ciprofloxacin and chloramphenicol. None of the E. coli isolates produced extended-spectrum beta-lactamases (ESBLs). The bla(TEM), aadA, aac(3)-II, tet(A) and/or tet(B), and the catA genes were demonstrated in all ampicillin, streptomycin, gentamicin, tetracycline, and chloramphenicol-resistant isolates respectively, and the sul1 and/or sul2 and/or sul3 genes in 4 of 5 sulfamethoxazole/trimethoprim resistant isolates. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (39 isolates), followed by E. faecium (21 isolates) and E. hirae (4 isolates). More than one-fourth (29.7%) of the isolates were resistant to tetracycline; 20.3% were resistant to erythromycin, 14.1% were resistant to ciprofloxacin and 10.9% were resistant to high-level-kanamycin. Lower level of resistance (quinupristin/dalfopristin and high-level-gentamicin, -streptomycin. No vancomycin-resistance was detected in the enterococci isolates. Resistance genes detected included aac(6')-aph(2''), ant(6)-Ia, tet(M) and/or tet(L) in all gentamicin, streptomycin and tetracycline-resistant isolates respectively. The aph(3')-IIIa gene was detected in 6 of 7 kanamycin-resistant isolates, the erm(B) gene in 11 of 13 erythromycin-resistant isolates and the vat(D) gene in the quinupristin/dalfopristin-resistant E. faecium isolate. This survey showed that faecal bacteria such as E. coli and enterococci of wild rabbits could be a reservoir of antimicrobial resistance genes. PMID:20624632

  12. Microarray Evaluation of Antimicrobial Resistance and Virulence of Escherichia coli Isolates from Portuguese Poultry

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    Nuno Mendonça

    2016-01-01

    Full Text Available The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70% and ampicillin (63%. Extended-spectrum beta-lactamase (ESBL phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA microarrays for the carriage of 88 antibiotic resistance genes and 62 virulence genes. Overall, 37 different resistance genes were detected. The most common were tet(A (72%, blaTEM (68%, and sul1 (47%, while 21% isolates harbored an ESBL gene (blaCTX-M group 1, group 2, or group 9. Of these, 96% carried the increased serum survival (iss virulence gene, while 89% presented the enterobactin siderophore receptor protein (iroN, 70% the temperature-sensitive hemagglutinin (tsh, and 68% the long polar fimbriae (lpfA virulence genes associated with extraintestinal pathogenic E. coli. In conclusion, prevalence of antibiotic resistant E. coli from the microbiota of Portuguese chickens was high, including to extended spectrum cephalosporins. The majority of isolates seems to have the potential to trigger extraintestinal human infection due to the presence of some virulence genes. However, the absence of genes specific for enteropathogenic E. coli reduces the risk for human intestinal infection.

  13. ANTIBACTERIAL ACTIVITY OF SOME WILD MEDICAL PLANTS EXTRACT TO ANTIBIOTIC RESISTANT ESCHERICHIA COLI

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    Lukáš Hleba

    2013-02-01

    Full Text Available Antibiotics are probably the most successful family of drugs so far developed for improving human health. Because of increasing resistance to antibiotics of many bacteria, plant extracts and plant compounds are of new interest as antiseptics and antimicrobial agents in medicine. In this study, we researched antimicrobial effects of extracts of some medical plants (Tussilagofarfara, Equisetum arvense, Sambucusnigra, Aesculushippocastanumand Taraxacumofficinale from Slovakia to antibiotic resistant and antibiotic sensitive bacteria isolated from milk of cows and mare, which were breeded in different conditions. Microorganisms which were used in this experiment we isolated from milk from conventional breeding of cows (tenE. coli strains and from ecological breeding of Lipicanmare (tenE. coli strains by sterile cotton swabs. For antibiotic susceptibility testing was used disc diffusion method according by EUCAST. After dried at room temperature we weighed 50 g of crushed medical plants (parts and it were to extract in 400 ml methanol for two weeks at room temperature. For antimicrobial susceptibility testing of medical plants extract blank discs with 6 mm diameter disc diffusion method was used. We determined that all Escherichia coli strains isolated from milk of conventional breeding of cows were resistant to ampicillin and chloramphenicol. We determined that all tested ampicillin and chloramphenicol resistant E. coli strains isolated from conventional breeding of cow showed susceptibility to all used medical plants extracts. In difference, we determined that antibiotic susceptible E. coli strains isolated from ecological breeding of Lipicanmare were susceptible to Tussilagofarfara extract only. From these results we could be conclude some observations, which could be important step in treatment of bacterial infections caused by antibiotic resistant bacteria and it could be important knowledge for treatment of livestock in conventional breeding

  14. Antibiotic resistance and resistance genes in Escherichia coli from poultry farms, southwest Nigeria

    DEFF Research Database (Denmark)

    Adelowo, Olawale O.; Fagade, Obasola E.; Agersø, Yvonne

    2014-01-01

    %, ampicillin 36%, spectinomycin 28%, nalidixic acid 25%, chloramphenicol 22%, neomycin 14%, gentamicin 8%, amoxicillin-clavulanate, ceftiofur, cefotaxime, colistin, florfenicol and apramycin 0%. Resistance genes found among the isolates include bla-TEM (85%), sul2 (67%), sul3 (17%), aadA (65%), strA (70%), str...

  15. PREVALENCE OF ANTIBIOTIC RESISTANT STRAINS OF ESCHERICHIA COLI AND ENTEROCOCCUS SPP. IN ROE DEER (CAPREOLUS CAPREOLUS AND RED DEER (CERVUS ELAPHUS AT THE PARCO NAZIONALE DEI MONTI SIBILLINI, ITALY

    Directory of Open Access Journals (Sweden)

    B. Cenci Goga

    2009-09-01

    Full Text Available A case control study was performed in the Parco Nazionale dei Monti Sibillini, Italy, to find out whether roe deer (Capreolus capreolus and red deer (Cervus elaphus were more likely to harbour antibiotic resistant Escherichia coli in their faeces, compared to Enterococcus spp. Ten areas were selected and samples were collected during a fourmonths (May to August, 2008 sampling period. Samples of water (n=12 and feces (n=59, collected at 10 different sites, were cultured for E. coli and Enterococcus spp. The resulting colonies were screened for tetracycline, ampicillin and kanamycin resistance using the Lederberg Replica Plating method (breakpoint 4 μg/ml. All resistant isolates were then selected, and subjected to the CLSI antimicrobial plate susceptibility test (7. Among the water specimens contaminated by E. coli, 80% were found to be resistant to ampicillin, 80% to tetracycline and 40% to kanamycin. Among the water specimens contaminated by Enterococcus spp., 14.29% were found to be resistant to ampicillin, 14.29% to tetracycline and 71.3% to kanamycin. Among the 39 strains of E. coli isolated from red deer feces, 12 were resistant to ampicillin (30.77%, 5 to tetracycline (12,82% and 3 to kanamycin (7.69%. Among the 19 strains of Enterococcus spp. isolated from red deer feces, 0 were resistant to ampicillin (0%, 1 to tetracycline (5.26% and 19 to kanamycin (100. These are significant findings, indicating that antibiotic resistance can be found in naïve animal populations and that red deer and fallow deer could act as sentinels for antimicrobial resistance. Key words Antibiotic-resistance, red deer, fallow deer, Escherichia

  16. Investigation of antimicrobial resistance in Escherichia coli and enterococci isolated from Tibetan pigs.

    Directory of Open Access Journals (Sweden)

    Peng Li

    Full Text Available OBJECTIVES: This study investigated the antimicrobial resistance of Escherichia coli and enterococci isolated from free-ranging Tibetan pigs in Tibet, China, and analyzed the influence of free-ranging husbandry on antimicrobial resistance. METHODS: A total of 232 fecal samples were collected from Tibetan pigs, and the disk diffusion method was used to examine their antimicrobial resistance. Broth microdilution and agar dilution methods were used to determine minimum inhibitory concentrations for antimicrobial agents for which disks were not commercially available. RESULTS: A total of 129 E. coli isolates and 84 Enterococcus isolates were recovered from the fecal samples. All E. coli isolates were susceptible to amoxicillin/clavulanic acid, and 40.4% were resistant to tetracycline. A small number of isolates were resistant to florfenicol (27.9%, ampicillin (27.9%, sulfamethoxazole/trimethoprim (19.4%, nalidixic acid (19.4%, streptomycin (16.2% and ceftiofur (10.9%, and very low resistance rates to ciprofloxacin (7.8%, gentamicin (6.9%, and spectinomycin (2.3% were observed in E. coli. All Enterococcus isolates, including E. faecium, E. faecalis, E. hirae, and E. mundtii, were susceptible to amoxicillin/clavulanic acid and vancomycin, but showed high frequencies of resistance to oxacillin (92.8%, clindamycin (82.1%, tetracycline (64.3%, and erythromycin (48.8%. Resistance rates to florfenicol (17.9%, penicillin (6.0%, ciprofloxacin (3.6%, levofloxacin (1.2%, and ampicillin (1.2% were low. Only one high-level streptomycin resistant E. faecium isolate and one high-level gentamicin resistant E. faecium isolate were observed. Approximately 20% and 70% of E. coli and Enterococcus isolates, respectively, were defined as multidrug-resistant. CONCLUSIONS: In this study, E. coli and Enterococcus isolated from free-ranging Tibetan pigs showed relatively lower resistance rates than those in other areas of China, where more intensive farming practices are

  17. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries.

    Directory of Open Access Journals (Sweden)

    Julia Österberg

    Full Text Available Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET resistant E. coli in colon content and/or faeces from individual pigs was determined. In all four countries the percentage resistance to ampicillin, streptomycin, sulphonamides or trimethoprim was significantly lower in E. coli from organic pigs. In France and Italy, the percentage of isolates resistant to chloramphenicol, ciprofloxacin, nalidixic acid or gentamicin was also significantly lower in the E. coli from organic pigs. Resistance to cefotaxime, was not found in any country. The percentage of E. coli isolates resistant to TET as well as the proportion of TET-resistant E. coli was significantly lower in organic than in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating that both country- and production-specific factors influence the occurrence of resistance.

  18. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries.

    Science.gov (United States)

    Österberg, Julia; Wingstrand, Anne; Nygaard Jensen, Annette; Kerouanton, Annaelle; Cibin, Veronica; Barco, Lisa; Denis, Martine; Aabo, Sören; Bengtsson, Björn

    2016-01-01

    Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC) of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET) resistant E. coli in colon content and/or faeces from individual pigs was determined. In all four countries the percentage resistance to ampicillin, streptomycin, sulphonamides or trimethoprim was significantly lower in E. coli from organic pigs. In France and Italy, the percentage of isolates resistant to chloramphenicol, ciprofloxacin, nalidixic acid or gentamicin was also significantly lower in the E. coli from organic pigs. Resistance to cefotaxime, was not found in any country. The percentage of E. coli isolates resistant to TET as well as the proportion of TET-resistant E. coli was significantly lower in organic than in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating that both country- and production-specific factors influence the occurrence of resistance. PMID:27362262

  19. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries

    Science.gov (United States)

    Nygaard Jensen, Annette; Kerouanton, Annaelle; Cibin, Veronica; Barco, Lisa; Denis, Martine; Aabo, Sören

    2016-01-01

    Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC) of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET) resistant E. coli in colon content and/or faeces from individual pigs was determined. In all four countries the percentage resistance to ampicillin, streptomycin, sulphonamides or trimethoprim was significantly lower in E. coli from organic pigs. In France and Italy, the percentage of isolates resistant to chloramphenicol, ciprofloxacin, nalidixic acid or gentamicin was also significantly lower in the E. coli from organic pigs. Resistance to cefotaxime, was not found in any country. The percentage of E. coli isolates resistant to TET as well as the proportion of TET-resistant E. coli was significantly lower in organic than in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating that both country- and production-specific factors influence the occurrence of resistance. PMID:27362262

  20. Characterization of Multiple-Antimicrobial-Resistant Escherichia coli Isolates from Diseased Chickens and Swine in China

    Science.gov (United States)

    Yang, Hanchun; Chen, Sheng; White, David G.; Zhao, Shaohua; McDermott, Patrick; Walker, Robert; Meng, Jianghong

    2004-01-01

    Escherichia coli isolates from diseased piglets (n = 89) and chickens (n = 71) in China were characterized for O serogroups, virulence genes, antimicrobial susceptibility, class 1 integrons, and mechanisms of fluoroquinolone resistance. O78 was the most common serogroup identified (63%) among the chicken E. coli isolates. Most isolates were PCR positive for the increased serum survival gene (iss; 97%) and the temperature-sensitive hemagglutinin gene (tsh; 93%). The O serogroups of swine E. coli were not those typically associated with pathogenic strains, nor did they posses common characteristic virulence factors. Twenty-three serogroups were identified among the swine isolates; however, 38% were O nontypeable. Overall, isolates displayed resistance to nalidixic acid (100%), tetracycline (98%), sulfamethoxazole (84%), ampicillin (79%), streptomycin (77%), and trimethoprim-sulfamethoxazole (76%). Among the fluoroquinolones, resistance ranged between 64% to levofloxacin, 79% to ciprofloxacin, and 95% to difloxacin. DNA sequencing of gyrA, gyrB, parC, and parE quinolone resistance-determining regions of 39 nalidixic acid-resistant E. coli isolates revealed that a single gyrA mutation was found in all of the isolates; mutations in parC together with double gyrA mutations conferred high-level resistance to fluoroquinolones (ciprofloxacin MIC, ≥8 μg/ml). Class 1 integrons were identified in 17 (19%) isolates from swine and 42 (47%) from chickens. The majority of integrons possessed genes conferring resistance to streptomycin and trimethoprim. These findings suggest that multiple-antimicrobial-resistant E. coli isolates, including fluoroquinolone-resistant variants, are commonly present among diseased swine and chickens in China, and they also suggest the need for the introduction of surveillance programs in China to monitor antimicrobial resistance in pathogenic bacteria that can be potentially transmitted to humans from food animals. PMID:15297487

  1. Virulence genes, antibiotic resistance and integrons in Escherichia coli strains isolated from synanthropic birds from Spain.

    Science.gov (United States)

    Sacristán, C; Esperón, F; Herrera-León, S; Iglesias, I; Neves, E; Nogal, V; Muñoz, M J; de la Torre, A

    2014-01-01

    The aim of this study was to determine the presence of virulence genes and antibiotic resistance profiles in 164 Escherichia coli strains isolated from birds (feral pigeons, hybrid ducks, house sparrows and spotless starlings) inhabiting urban and rural environments. A total of eight atypical enteropathogenic E. coli strains were identified: one in a house sparrow, four in feral pigeons and three in spotless starlings. Antibiotic resistance was present in 32.9% (54) of E. coli strains. The dominant type of resistance was to tetracycline (21.3%), ampicillin (19.5%) and sulfamethoxazole (18.9%). Five isolates had class 1 integrons containing gene cassettes encoding for dihydrofolate reductase A (dfrA) and aminoglycoside adenyltransferase A (aadA), one in a feral pigeon and four in spotless starlings. To our knowledge, the present study constitutes the first detection of virulence genes from E. coli in spotless starlings and house sparrows, and is also the first identification worldwide of integrons containing antibiotic resistance gene cassettes in E. coli strains from spotless starlings and pigeons. PMID:24689431

  2. Resistance patterns, ESBL genes, and genetic relatedness of Escherichia coli from dogs and owners

    Science.gov (United States)

    Carvalho, A.C.; Barbosa, A.V.; Arais, L.R.; Ribeiro, P.F.; Carneiro, V.C.; Cerqueira, A.M.F.

    2016-01-01

    Antimicrobial resistance in Escherichia coli isolated from pet dogs can be considered a potential threat of infection for the human population. Our objective was to characterize the resistance pattern, extended spectrum beta-lactamase production and genetic relatedness of multiresistant E. coli strains isolated from dogs (n = 134), their owners (n = 134), and humans who claim to have no contact with dogs (n = 44, control), searching for sharing of strains. The strains were assessed for their genetic relatedness by phylogenetic grouping and pulsed-field gel electrophoresis. Multiresistant E. coli strains were isolated from 42 (31.3%) fecal samples from pairs of dogs and owners, totaling 84 isolates, and from 19 (43.1%) control group subjects. The strains showed high levels of resistance to ampicillin, streptomycin, tetracycline, trimethoprim and sulfamethoxazole regardless of host species or group of origin. The blaTEM, blaCTX-M, and blaSHV genes were detected in similar proportions in all groups. All isolates positive for bla genes were ESBL producers. The phylogenetic group A was the most prevalent, irrespective of the host species. None of the strains belonging to the B2 group contained bla genes. Similar resistance patterns were found for strains from dogs, owners and controls; furthermore, identical PFGE profiles were detected in four (9.5%) isolate pairs from dogs and owners, denoting the sharing of strains. Pet dogs were shown to be a potential household source of multiresistant E. coli strains. PMID:26887238

  3. Prevalence and Antimicrobial Resistance in Escherichia coli from Food Animals in Lagos, Nigeria.

    Science.gov (United States)

    Adenipekun, Eyitayo O; Jackson, Charlene R; Oluwadun, Afolabi; Iwalokun, Bamidele A; Frye, Jonathan G; Barrett, John B; Hiott, Lari M; Woodley, Tiffanie A

    2015-06-01

    Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing animals from Lagos, Nigeria, was investigated. From December 2012 to June 2013, E. coli were isolated from fecal samples of healthy cattle, chicken, and swine. Antimicrobial susceptibility testing against 22 antimicrobials was performed using broth microdilution with the Sensititre™ system. Clonal types were determined by pulsed-field gel electrophoresis (PFGE). From the analysis, 211/238 (88.7%), 170/210 (81%), and 136/152 (89.5%) samples from cattle, chicken, and swine, respectively, were positive for E. coli. A subset of those isolates (n=211) selected based on β-lactamase production was chosen for further study. Overall, E. coli exhibited the highest resistance to tetracycline (124/211; 58.8%), trimethoprim/sulfamethoxazole (84/211; 39.8%), and ampicillin (72/211; 34.1%). Approximately 40% of the isolates were pan-susceptible, and none of the isolates were resistant to amikacin, cefepime, ceftazidime, ertapenem, meropenem, or tigecycline. Among the resistant isolates, 28 different resistance patterns were observed; 26 of those were characterized as multi-drug resistant (MDR; resistance to ≥2 antimicrobials). One isolate was resistant to 13 different antimicrobials representing five different antimicrobial classes. Using PFGE, MDR E. coli were genetically diverse and overall did not group based on source; identical PFGE patterns were detected among isolates from different sources. These results suggest that isolates cannot be attributed to specific sources, and some may be present across all of the sources. Results from this study indicate that food-producing animals in Nigeria are a reservoir of MDR E. coli that may be transferred to humans via the food chain. PMID

  4. Surveillance and Detection of Inhibitor-Resistant Beta-Lactamases in Clinical Isolates of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Carl Urban

    2007-06-01

    Full Text Available In recent years, resistance to beta-lactam antibiotics, such as the widely-used cephalosporins and penicillins, has become a major challenge for disease therapy, particularly in common hospital-acquired infections. In the search for the mechanisms behind this increasingly prevalent form of resistance, microbiologists have identified a new type of beta-lactamase enzyme, called inhibitor-resistant TEMs (IRTs, which can withstand the effects of beta-lactamase inhibitor compounds, further reducing the arsenal of drugs available to physicians facing resistant bacteria. In this study, we examined the enzymatic and genetic basis of Escherichia coli isolates demonstrating such resistance to beta-lactam/beta-lactamase inhibitor combinations. Susceptibility trials played a major role in composing the experimental cohort for this project (n=50; each isolate was thoroughly tested to ensure that it was resistant to ampicillin-sulbactam, an inhibitor combination, but susceptible to the third-generation cephalosporin ceftazidime. Subsequently, a number of samples were subjected to assay by pulsed-field gel electrophoresis (n=18 and polymerase chain reaction (n=3 so that their genetic composition and relatedness might be known. In particular, the presence of genes coding for TEM-type beta-lactamases was investigated for each of the 3 isolates sequenced. Even though it was anticipated that the isolates would possess resistance to inhibitor combinations due to an IRT gene, this was not found to be the case. Instead, the mechanism of resistance turned out to be over-expression of a gene coding for a normal TEM enzyme. The results of these experiments have implications for ensuring successful therapy of bacterial infections and for preventing the spread of antimicrobial resistance.

  5. Multidrug-resistant and epidemic clones of Escherichia coli from natural beds of Venus clam.

    Science.gov (United States)

    Vignaroli, C; Di Sante, L; Leoni, F; Chierichetti, S; Ottaviani, D; Citterio, B; Biavasco, F

    2016-10-01

    Epidemic Escherichia coli clones have been recovered in marine sediment along the coast of Marche, an Adriatic region in central Italy. In the present study, E. coli strains from the clam Chamelea gallina, sampled from seven natural beds in the same area, were detected. Selected E. coli isolates from all sampling sites were screened for antimicrobial susceptibility, genetic diversity and correlation. The majority (60%) belonged to phylogroups A or B1, 31% to the other groups (B2, C, D, E, F), 8% to cryptic clades, and 1% were untypable. Moreover, 33.3% of isolates were resistant to at least one drug and 11% were multidrug resistant (MDR). The most common resistance was to tetracycline, ampicillin, and streptomycin. No clonality was detected, but the strains' high genetic heterogeneity pointed at multiple sources of microbiological contamination. MLST analysis found potentially pathogenic and even epidemic MDR strains in clams collected in class A (ST746 and ST46) and class B (ST393, ST58 and ST131) areas, indicating that strains of clinical origin are detectable in clams. These data highlight that eating raw or lightly cooked clams may pose a health risk if purification is not performed or is ineffective. PMID:27375238

  6. Lethal neonatal meningoencephalitis caused by multi-drug resistant, highly virulent Escherichia coli.

    Science.gov (United States)

    Iqbal, Junaid; Dufendach, Kevin R; Wellons, John C; Kuba, Maria G; Nickols, Hilary H; Gómez-Duarte, Oscar G; Wynn, James L

    2016-06-01

    Neonatal meningitis is a rare but devastating condition. Multi-drug resistant (MDR) bacteria represent a substantial global health risk. This study reports on an aggressive case of lethal neonatal meningitis due to a MDR Escherichia coli (serotype O75:H5:K1). Serotyping, MDR pattern and phylogenetic typing revealed that this strain is an emergent and highly virulent neonatal meningitis E. coli isolate. The isolate was resistant to both ampicillin and gentamicin; antibiotics currently used for empiric neonatal sepsis treatment. The strain was also positive for multiple virulence genes including K1 capsule, fimbrial adhesion fimH, siderophore receptors iroN, fyuA and iutA, secreted autotransporter toxin sat, membrane associated proteases ompA and ompT, type II polysaccharide synthesis genes (kpsMTII) and pathogenicity-associated island (PAI)-associated malX gene. The presence of highly-virulent MDR organisms isolated in neonates underscores the need to implement rapid drug resistance diagnostic methods and should prompt consideration of alternate empiric therapy in neonates with Gram negative meningitis. PMID:27030919

  7. Comparative efficacies of pivmecillinam and ampicillin in acute shigellosis.

    Science.gov (United States)

    Kabir, I; Rahaman, M M; Ahmed, S M; Akhter, S Q; Butler, T

    1984-05-01

    The clinical efficacies of pivmecillinam and ampicillin were compared in a randomized double-blind trial in the treatment of acute shigellosis. Of 44 adult male patients, all culture positive for Shigella strains, 22 patients received 400 mg of pivmecillinam and 22 patients received 500 mg of ampicillin every 6 h. Both drugs were administered orally for 5 days. Four patients receiving ampicillin were infected with Shigella strains that were resistant to ampicillin but susceptible to pivmecillinam, and two patients receiving pivmecillinam were infected with Shigella strains resistant to both ampicillin and pivmecillinam. The mean duration of diarrhea in all patients receiving pivmecillinam was 3.3 days compared with 4.5 days in patients receiving ampicillin (P less than 0.05). When patients infected with the resistant strains were excluded, the mean duration of diarrhea in patients receiving pivmecillinam was 3.2 days compared with 4.1 days in patients receiving ampicillin. The patients infected with strains susceptible to both antibiotics had mean durations of fecal excretion of Shigella strains of 1.2 days for those treated with pivmecillinam and 1.4 days for those treated with ampicillin. The patients infected with organisms resistant to both drugs had longer durations of diarrhea and fecal excretion of Shigella strains. The results suggest that pivmecillinam is as effective as ampicillin and can be a useful drug for the treatment of shigellosis. PMID:6329092

  8. Prevalence of macrolide-non-susceptible isolates among β-lactamase-negative ampicillin-resistant Haemophilus influenzae in a tertiary care hospital in Japan.

    Science.gov (United States)

    Wajima, Takeaki; Seyama, Shoji; Nakamura, Yuka; Kashima, Chihiro; Nakaminami, Hidemasa; Ushio, Masanobu; Fujii, Takeshi; Noguchi, Norihisa

    2016-09-01

    β-Lactamase-negative ampicillin-resistant (BLNAR) Haemophilus influenzae account for a large portion of H. influenzae clinical isolates in Japan. The aim of this study was to clarify the antimicrobial susceptibility of BLNAR H. influenzae clinical isolates as well as the annual changes in susceptibility. BLNAR H. influenzae isolates were collected from a tertiary care hospital from 2007 to 2012. Antimicrobial susceptibility testing was performed and resistance mechanisms were analysed. All of the isolates (n=304) had amino acid substitutions in penicillin-binding protein 3 (PBP3) and isolates were classified by these amino acid substitutions: R517H or N526K (class I); S385T and R517H (class II); and S385T and N526K (class III). Classes I, II and III represented 8.2% (n=25), 9.5% (n=29) and 81.6% (n=248) of the isolates, respectively; 2 isolates could not be classified because they had a PBP3 with a substantially mutated FtsI transpeptidase domain. All of the isolates were highly susceptible to fluoroquinolones and carbapenems. The number of clarithromycin (CAM)-non-susceptible [minimum inhibitory concentration (MIC) ≥16μg/mL] H. influenzae isolates increased significantly between 2010 and 2012. Moreover, CAM-non-susceptible H. influenzae isolates were prevalent among class II and class III BLNAR H. influenzae. Multilocus sequence typing (MLST) of the CAM-resistant (MIC ≥32μg/mL) H. influenzae isolates showed that they were not specific sequence types, suggesting that CAM resistance may occur in any isolates. These results raise concern regarding the occurrence of multidrug-resistant BLNAR H. influenzae. PMID:27530834

  9. Genetic determinants of heat resistance in Escherichia coli

    OpenAIRE

    Ryan eMercer; Jinshui eZheng; Rigoberto eGarcia-Hernandez; Lifang eRuan; Michael eGänzle; Lynn eMcMullen

    2015-01-01

    Escherichia coli AW1.7 is a heat resistant food isolate and the occurrence of pathogenic strains with comparable heat resistance may pose a risk to food safety. To identify the genetic determinants of heat resistance, 29 strains of E. coli that differed in their of heat resistance were analyzed by comparative genomics. Strains were classified as highly heat resistant strains, exhibiting a D60-value of more than 6 min; moderately heat resistant strains, exhibiting a D60-value of more than 1 mi...

  10. Antimicrobial resistance of Escherichia coli isolated in newly-hatched chickens and effect of amoxicillin treatment during their growth.

    Science.gov (United States)

    Jiménez-Belenguer, Ana; Doménech, Eva; Villagrá, Arantxa; Fenollar, Alejandro; Ferrús, Maria Antonia

    2016-08-01

    The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. However, other factors may also play a part, and in particular vertical spread between the generations has been suggested to be an important transmission pathway. The objective of this paper was to determine the resistance patterns of Escherichia coli isolated from newly-hatched chickens as well as to study the antibiotic pressure effect when amoxicillin was administered during their growing period. With this aim, meconium from 22 one-day-old Ross chickens was analysed. In addition, during their growth period, amoxicillin treatments at days 7, 21 and 35 were carried out. Results showed a high number of E. coli-resistant strains were isolated from the treated one-day-old chickens, and were the highest for β-lactams group, followed by quinolone and tetracyclines. After treatment with amoxicillin, the highest percentage of resistances were detected for this antibiotic compared to the others analysed, with significant differences in resistance percentages between control and treated broilers detected in relation to ampicillin, cephalothin, streptomycin, kanamycin, gentamicin, chloramphenicol and tetracycline. Differences in resistances to ciprofloxacin and nalidixic acid between control and treated animals were not observed and there was lack of resistance for amikacin and ceftriaxone. These results suggest the possibility of vertical transmission of resistant strains to newly-hatched chicks from parent flocks, and seem to indicate that the treatment with amoxicillin increased the resistance of E. coli to other antibiotics. PMID:27035748

  11. Enterobacterial detection and Escherichia coli antimicrobial resistance in parrots seized from the illegal wildlife trade.

    Science.gov (United States)

    Hidasi, Hilari Wanderley; Hidasi Neto, José; Moraes, Dunya Mara Cardoso; Linhares, Guido Fontgallad Coelho; Jayme, Valéria de Sá; Andrade, Maria Auxiliadora

    2013-03-01

    Enteric bacteria are considered important potential pathogens in avian clinical medicine, causing either primary or opportunistic infections. The aim of this study was to evaluate the frequency of enterobacteria in the intestinal microbiota of psittacine birds and to determine the antimicrobial susceptibility of the Escherichia coli isolates cultured. Fecal samples were collected from 300 parrots captured from the illegal wildlife trade in Goiás, Brazil and were processed using conventional bacteriological procedures. A total of 508 isolates were obtained from 300 fecal samples: 172 E. coli (33.9% of isolates; 57.3% of individuals); 153 Enterobacter spp. (30.1% of isolates; 51.0% of individuals); 89 Klebsiella spp. (17.7% of isolates; 29.7% of individuals); 59 Citrobacter spp. (11.6% of isolates; 19.7% of individuals), 21 Proteus vulgaris (4.2% of isolates; 7.0% of individuals), 5 Providencia alcalifaciens (0.98% of isolates; 1.67% of individuals), 5 Serratia sp. (0.98% of isolates; 1.67% of individuals), 3 Hafnia aivei (0.59% of isolates; 1.00% of individuals), and 1 Salmonella sp. (0.20% of isolates; 0.33% of individuals). Escherichia coli isolates were subsequently tested for susceptibility to the following antibiotics: amoxicillin (70.93% of the isolates were resistant), ampicillin (75.58%), ciprofloxacin (23.25%), chloramphenicol (33.14%), doxycycline (64.53%), enrofloxacin (41.28%), tetracycline (69.19%), and sulfonamide (71.51%). Multi-resistance to three and four groups of antibiotics occurred in 40 samples (23.25%) and 4 samples (2.32%), respectively. These results demonstrate that illegally traded birds are carriers of potentially pathogenic bacteria, including E. coli strains with antimicrobial resistance. PMID:23505696

  12. Widespread antibiotic resistance of diarrheagenic Escherichia coli and Shigella species

    OpenAIRE

    Azam Fatahi Sadeghabadi; Ali Ajami; Reza Fadaei; Masoud Zandieh; Elham Heidari; Mahmoud Sadeghi; Behrooz Ataei; Shervin Ghaffari Hoseini

    2014-01-01

    Background: Antibiotic resistance of enteric pathogens particularly Shigella species, is a critical world-wide problem and monitoring their resistant pattern is essential, because the choice of antibiotics is absolutely dependent on regional antibiotic susceptibility patterns. During summer 2013, an unusual increase in number of diarrheal diseases was noticed in Isfahan, a central province of Iran. Therefore, the antibiotic resistance of diarrheagenic Escherichia coli and Shigella species iso...

  13. Transmission of antibiotic-resistant Escherichia coli between cattle, humans and the environment in peri-urban livestock keeping communities in Morogoro, Tanzania

    DEFF Research Database (Denmark)

    Lupindu, Athumani M; Dalsgaard, Anders; Msoffe, Peter L. M.;

    2015-01-01

    Urban and peri-urban livestock farming is expanding world-widely because of increased urbanization and demands for food of animal origin. Such farming practices pose a public health risk as livestock are reservoirs of several zoonotic pathogens. In an attempt to determine the fecal transmission...... urban and peri-urban farming....... between livestock and people, 100 household clusters keeping cattle in close proximity of humans were selected in urban and peri-urban areas of Morogoro in Tanzania. One hundred eighteen ampicillin and tetracycline resistant Escherichia coli (40 from human stool, 50 from cattle feces, 21 from soil and...

  14. Dogs are a reservoir of ampicillin-resistant Enterococcus faecium lineages associated with human infections

    DEFF Research Database (Denmark)

    Damborg, Peter Panduro; Top, Janetta; Hendrickx, Antoni P.A.;

    2009-01-01

    generally differed from those previously described for clinical human isolates. The results indicate that dogs are frequent carriers of CC17-related lineages and may play a role in the spread of this nosocomial pathogen. The distinctive virulence and antimicrobial resistance profiles observed among canine...... AREF isolates raise interesting questions about the origin and evolution of the strains causing human infections....

  15. Mechanobiology of Antimicrobial Resistant Escherichia coli and Listeria innocua

    Science.gov (United States)

    Tajkarimi, Mehrdad; Harrison, Scott H.; Hung, Albert M.; Graves, Joseph L.

    2016-01-01

    A majority of antibiotic-resistant bacterial infections in the United States are associated with biofilms. Nanoscale biophysical measures are increasingly revealing that adhesive and viscoelastic properties of bacteria play essential roles across multiple stages of biofilm development. Atomic Force Microscopy (AFM) applied to strains with variation in antimicrobial resistance enables new opportunities for investigating the function of adhesive forces (stickiness) in biofilm formation. AFM force spectroscopy analysis of a field strain of Listeria innocua and the strain Escherichia coli K-12 MG1655 revealed differing adhesive forces between antimicrobial resistant and nonresistant strains. Significant increases in stickiness were found at the nanonewton level for strains of Listeria innocua and Escherichia coli in association with benzalkonium chloride and silver nanoparticle resistance respectively. This advancement in the usage of AFM provides for a fast and reliable avenue for analyzing antimicrobial resistant cells and the molecular dynamics of biofilm formation as a protective mechanism. PMID:26914334

  16. Production of ACAT1 56-kDa isoform in human cells via trans-splicing involving the ampicillin resistance gene

    Institute of Scientific and Technical Information of China (English)

    Guang-Jing Hu; Jia Chen; Xiao-Nan Zhao; Jia-Jia Xu; Dong-Qing Guo; Ming Lu; Ming Zhu

    2013-01-01

    Trans-splicing,a process involving the cleavage and joining of two separate transcripts,can expand the transcriptome and proteome in eukaryotes.Chimeric RNAs generated by trans-splicing are increasingly described in literatures.The widespread presence of antibiotic resistance genes in natural environments and human intestines is becoming an important challenge for public health.Certain antibiotic resistance genes,such as ampicillin resistance gene (Amp),are frequently used in recombinant plasmids.Until now,trans-splicing involving recombinant plasmid-derived exogenous transcripts and endogenous cellular RNAs has not been reported.Acyl-CoA:cholesterol acyltransferase 1 (ACAT1) is a key enzyme involved in cellular cholesterol homeostasis.The 4.3-kb human ACAT1 chimeric mRNA can produce 50-kDa and 56-kDa isoforms with different enzymatic activities.Here,we show that human ACAT1 56-kDa isoform is produced from an mRNA species generated through the trans-splicing of an exogenous transcript encoded by the antisense strand of Ampr (asAmp) present in common Ampr-plasmids and the 4.3-kb endogenous ACAT1 chimeric mRNA,which is presumably processed through a prior event of interchromosomal trans-splicing.Strikingly,DNA fragments containing the asAmp with an upstream recombined cryptic promoter and the corresponding exogenous asAmp transcripts have been detected in human cells.Our findings shed lights on the mechanism of human ACAT1 56-kDa isoform production,reveal an exogenous-endogenous trans-splicing system,in which recombinant plasmid-derived exogenous transcripts are linked with endogenous cellular RNAs in human cells,and suggest that exogenous DNA might affect human gene expression at both DNA and RNA levels.

  17. Association Between Antimicrobial Resistance in Escherichia coli Isolates from Food Animals and Blood Stream Isolates from Humans in Europe: An Ecological Study

    DEFF Research Database (Denmark)

    Vieira, Antonio; Collignon, Peter; Aarestrup, Frank Møller;

    2011-01-01

    Background: In addition to medical antimicrobial usage, the use of antimicrobials in food animals contributes to the occurrence of resistance among some bacterial species isolated from infections in humans. Recently, several studies have indicated that a large proportion of Escherichia coli causing...... infections in humans, especially those resistant to antimicrobials, have an animal origin.Methods: We analyzed the correlation between the prevalence of antimicrobial resistance in E. coli isolates from blood stream infections in humans and in E. coli isolates from poultry, pigs, and cattle between 2005 and...... 2008 for 11 countries, using available surveillance data. We also assessed the correlation between human antimicrobial usage and the occurrence of resistance in E. coli isolates from blood stream infections.Results: Strong and significant correlations between prevalences of resistance to ampicillin (r...

  18. Diversity of Plasmids and Antimicrobial Resistance Genes in Multidrug-Resistant Escherichia coli Isolated from Healthy Companion Animals.

    Science.gov (United States)

    Jackson, C R; Davis, J A; Frye, J G; Barrett, J B; Hiott, L M

    2015-09-01

    The presence and transfer of antimicrobial resistance genes from commensal bacteria in companion animals to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. The purpose of this study was to determine antimicrobial resistance gene content and the presence of genetic elements in antimicrobial resistant Escherichia coli from healthy companion animals. In our previous study, from May to August, 2007, healthy companion animals (155 dogs and 121 cats) from three veterinary clinics in the Athens, GA, USA area were sampled and multidrug-resistant E. coli (n = 36; MDR, resistance to ≥ 2 antimicrobial classes) were obtained. Of the 25 different plasmid replicon types tested by PCR, at least one plasmid replicon type was detected in 94% (34/36) of the MDR E. coli; four isolates contained as many as five different plasmid replicons. Nine replicon types (FIA, FIB, FII, I2, A/C, U, P, I1 and HI2) were identified with FIB, FII, I2 as the most common pattern. The presence of class I integrons (intI) was detected in 61% (22/36) of the isolates with eight isolates containing aminoglycoside- and/or trimethoprim-resistance genes in the variable cassette region of intI. Microarray analysis of a subset of the MDR E. coli (n = 9) identified the presence of genes conferring resistance to aminoglycosides (aac, aad, aph and strA/B), β-lactams (ampC, cmy, tem and vim), chloramphenicol (cat), sulfonamides (sulI and sulII), tetracycline [tet(A), tet(B), tet(C), tet(D) and regulator, tetR] and trimethoprim (dfrA). Antimicrobial resistance to eight antimicrobials (ampicillin, cefoxitin, ceftiofur, amoxicillin/clavulanic acid, streptomycin, gentamicin, sulfisoxazole and trimethoprim-sulfamethoxazole) and five plasmid replicons (FIA, FIB, FII, I1 and I2) were transferred via conjugation. The presence of antimicrobial resistance genes, intI and transferable plasmid replicons indicate that E. coli from companion animals may play an important role in the

  19. Antimicrobial drug resistance of Escherichia coli isolated from poultry abattoir workers at risk and broilers on antimicrobials

    Directory of Open Access Journals (Sweden)

    J.W. Oguttu

    2008-05-01

    Full Text Available Antimicrobial usage in food animals increases the prevalence of antimicrobial drug resistance among their enteric bacteria. It has been suggested that this resistance can in turn be transferred to people working with such animals, e.g. abattoir workers. Antimicrobial drug resistance was investigated for Escherichia coli from broilers raised on feed supplemented with antimicrobials, and the people who carry out evisceration, washing and packing of intestines in a high-throughput poultry abattoir in Gauteng, South Africa. Broiler carcasses were sampled from 6 farms, on each of which broilers are produced in a separate 'grow-out cycle'. Per farm, 100 caeca were randomly collected 5 minutes after slaughter and the contents of each were selectively cultured for E. coli. The minimum inhibitory concentration (MIC of each isolate was determined for the following antimicrobials : doxycycline, trimethoprim, sulphamethoxazole, ampicillin, enrofloxacin, fosfomycin, ceftriaxone and nalidixic acid. The same was determined for the faeces of 29 abattoir workers and 28 persons used as controls. The majority of isolates from broilers were resistant, especially to antimicrobials that were used on the farms in the study. Overall median MICs and the number of resistant isolates from abattoir workers (packers plus eviscerators tended to be higher than for the control group. However, no statistically significant differences were observed when the median MICs of antimicrobials used regularly in poultry and percentage resistance were compared, nor could an association between resistance among the enteric E. coli from packers and those from broilers be demonstrated.

  20. Multidrug-Resistant Escherichia coli in Bovine Animals, Europe.

    Science.gov (United States)

    Brennan, Evan; Martins, Marta; McCusker, Matthew P; Wang, Juan; Alves, Bruno Martins; Hurley, Daniel; El Garch, Farid; Woehrlé, Frédérique; Miossec, Christine; McGrath, Leisha; Srikumar, Shabarinath; Wall, Patrick; Fanning, Séamus

    2016-09-01

    Of 150 Escherichia coli strains we cultured from specimens taken from cattle in Europe, 3 had elevated MICs against colistin. We assessed all 3 strains for the presence of the plasmid-mediated mcr-1 gene and identified 1 isolate as mcr-1-positive and co-resistant to β-lactam, florfenicol, and fluoroquinolone antimicrobial compounds. PMID:27533105

  1. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014).

    Science.gov (United States)

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-12-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin in veal calves and chickens, for ciprofloxacin and nalidixic acid in chickens, for sulfamethoxazole in veal calves, chickens and pigs and for tetracycline in veal calves. Using logistic regression and Generalized Estimating Equation and after p value adjustment for multiple testing (Linear step-up method), statistically significant decreasing temporal trends were observed for several of the 11 tested antimicrobials in several livestock categories: in veal calves (10/11), in chickens (6/11) and in pigs (5/11). A significant increasing trend was observed for the prevalence of resistance to ciprofloxacin in chickens. Multi-resistance, considered as the resistance to at least three antimicrobials of different antibiotic classes, was observed in the four livestock categories but was significantly decreasing in veal calves, chickens and pigs. Overall, the prevalence of resistance and of multi-resistance was lowest in the beef cattle livestock category and highest in broiler chickens. These decreasing temporal trends of antimicrobial resistance might be due to a decrease of the total antimicrobial consumption for veterinary use in Belgium which was reported for the period between 2010 and 2013. The methodology and statistical tools developed in this study provide outputs which can detect shifts in resistance levels or resistance trends associated with particular antimicrobial classes and livestock categories. Such outputs can be used as objective evidence to evaluate the possible

  2. Heterologously expressed bacterial and human multidrug resistance proteins confer cadmium resistance to Escherichia coli

    NARCIS (Netherlands)

    Achard-Joris, M; van Saparoea, HBV; Driessen, AJM; Bourdineaud, JP; Bourdineaud, Jean-Paul

    2005-01-01

    The human MDR1 gene is induced by cadmium exposure although no resistance to this metal is observed in human cells overexpressing hMDR1. To access the role of MDR proteins in cadmium resistance, human MDR1, Lactococcus lactis lmrA, and Oenococcus oeni omrA were expressed in an Escherichia coli tolC

  3. Molecular basis of valine resistance in Escherichia coli K-12.

    OpenAIRE

    Lawther, R P; Calhoun, D H; Adams, C W; Hauser, C A; Gray, J.; Hatfield, G W

    1981-01-01

    The relationship of valine resistance to the expression of the ilvGEDA operon of Escherichia coli K-12 has been determined. DNA sequence and in vivo protein analyses indicate that in wild-type E. coli K-12 there is a frameshift site within the gene (ilvG) for valine resistance. The ilvG+2096 (formerly designated ilv02096) mutation displaces this frameshift site, resulting in the expression of ilvG and the relief of transcriptional polarity on the distal genes of this operon. Thus, the "ilv0" ...

  4. Possible transfer of plasmid mediated third generation cephalosporin resistance between Escherichia coli and Shigella sonnei in the human gut.

    Science.gov (United States)

    Rashid, Harunur; Rahman, Mahbubur

    2015-03-01

    Choice of antibiotic for treatment of serious bacterial infection is rapidly diminishing by plasmid mediated transfer of antibiotic resistance. Here, we report a possible horizontal transfer of plasmid carrying third-generation-cephalosporin (TGC) resistance between Escherichia coli and Shigella sonnei. Two different types of colonies were identified in MacConkey agar plate from a faecal specimen collected from a patient with shigellosis. The colonies were identified as E. coli and S. sonnei. Both of the isolates were resistant to ampicillin, chloramphenicol, co-trimoxazole, erythromycin, azithromycin, nalidixic acid, ceftriaxone, cefixime, ceftazidime, cefotaxime and susceptible to co-amoxiclave, amikacin, imipenam, astreonam, levofloxacin, moxifloxacin, mecillinam. These two strains were positive for extended spectrum β-lactamase. We were able to transfer ESBL producing property from both ceftriaxone-resistant isolates to the ceftriaxone susceptible recipient E. coli K12 and S. sonnei. Plasmid profile analysis revealed that the first-generation E. coli K12 and S. sonnei transconjugants harbored a 50MDa R plasmid, as two-parent ESBL-producing S. sonnei and E. coli strains. Similar patterns of ESBL producing plasmid and transferable antimicrobial phenotype suggests that the ESBL producing plasmid might transferred between E. coli and S. sonnei through conjugation in the human gut. PMID:25461693

  5. Mecanismos moleculares de resistencia antibiótica en Escherichia coli asociadas a diarrea Molecular mechanisms of antibiotic resistance in Escherichia coli- associated diarrhea

    Directory of Open Access Journals (Sweden)

    Susan Mosquito

    2011-12-01

    Full Text Available La resistencia antibiótica es un problema emergente a nivel mundial presente en diversas bacterias, en especial en la Escherichia coli, que tiene altos porcentajes de resistencia hacia ampicilina, trimetoprim-sulfametoxazol, tetraciclina, cloramfenicol y ácido nalidíxico, lo que supone grandes complicaciones en el tratamiento antibiótico cuando este es requerido. Este aumento de resistencia antibiótica se debe a la adquisición de diferentes mecanismos moleculares de resistencia mediante mutaciones puntuales a nivel cromosómico o transferencia horizontal de material genético entre especies relacionadas o diferentes, facilitada por algunos elementos genéticos tales como los integrones. Esta revisión discute los efectos de los mecanismos moleculares de resistencia más comunes en E.coli: inactivación enzimática, alteraciones en el sitio blanco y alteraciones de la permeabilidad. El conocer los mecanismos de resistencia implicados, como lo recomienda la Organización Mundial de la Salud, permitirá optimizar la vigilancia de resistencia y las políticas de control y uso de antibióticos a nivel nacional.Antibiotic resistance is an emerging problem worldwide present in many bacteria, specially in Escherichia coli, which has high percentages of resistance to ampicilline, thrimethoprim-sulfamethoxazole, tetracycline, chloramphenicol and nalidixic acid, which implies important complications in antibiotic treatment when required. The increasing antibiotic resistance is due to the acquisition of different molecular mechanisms of resistance through point chromosomal mutations and /or horizontal transfer of genetic material between related or different species facilitated by some genetic elements such as integrons. This review discusses the effects of the most common molecular mechanisms of antibiotic resistance in E. coli: enzymatic inactivation, changes in the target site and permeability disturbances. Getting to know the mechanisms of

  6. Plasmid-mediated formaldehyde resistance in Escherichia coli: characterization of resistance gene.

    OpenAIRE

    Kümmerle, N; Feucht, H H; Kaulfers, P M

    1996-01-01

    The formaldehyde resistance mechanisms in the formaldehyde-resistant strain Escherichia coli VU3695 were investigated. A large (4.6-kb) plasmid DNA fragment encompassing the formaldehyde resistance gene was sequenced. A single 1,107-bp open reading frame encoding a glutathione- and NAD-dependent formaldehyde dehydrogenase was identified and sequenced, and the enzyme was expressed in an in vitro assay and purified. Amino acid sequence homology studies showed 62.4 to 63.2% identity with class I...

  7. Antimicrobial resistance, virulence factors and genetic diversity of Escherichia coli isolates from household water supply in Dhaka, Bangladesh.

    Directory of Open Access Journals (Sweden)

    Prabhat Kumar Talukdar

    Full Text Available BACKGROUND: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity. METHODOLOGY/PRINCIPAL FINDINGS: A total of 233 E. coli isolates obtained from 175 tap water samples were analysed for susceptibility to 16 different antibiotics and for the presence of genes associated with virulence and antibiotic resistance. Nearly 36% (n = 84 of the isolates were multi-drug(≥ 3 classes of antibiotics resistant (MDR and 26% (n = 22 of these were positive for extended spectrum β-lactamase (ESBL. Of the 22 ESBL-producers, 20 were positive for bla CTX-M-15, 7 for bla OXA-1-group (all had bla OXA-47 and 2 for bla CMY-2. Quinolone resistance genes, qnrS and qnrB were detected in 6 and 2 isolates, respectively. Around 7% (n = 16 of the isolates carried virulence gene(s characteristic of pathogenic E. coli; 11 of these contained lt and/or st and thus belonged to enterotoxigenic E. coli and 5 contained bfp and eae and thus belonged to enteropathogenic E. coli. All MDR isolates carried multiple plasmids (2 to 8 of varying sizes ranging from 1.2 to >120 MDa. Ampicillin and ceftriaxone resistance were co-transferred in conjugative plasmids of 70 to 100 MDa in size, while ampicillin, trimethoprim-sulfamethoxazole and tetracycline resistance were co-transferred in conjugative plasmids of 50 to 90 MDa. Pulsed-field gel electrophoresis analysis revealed diverse genetic fingerprints of pathogenic isolates. SIGNIFICANCE: Multi-drug resistant E. coli are wide spread in public water supply in Dhaka city, Bangladesh. Transmission of resistant bacteria and plasmids through supply water pose serious threats to public health in

  8. Genetic determinants of heat resistance in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Ryan eMercer

    2015-09-01

    Full Text Available Escherichia coli AW1.7 is a heat resistant food isolate and the occurrence of pathogenic strains with comparable heat resistance may pose a risk to food safety. To identify the genetic determinants of heat resistance, 29 strains of E. coli that differed in their of heat resistance were analyzed by comparative genomics. Strains were classified as highly heat resistant strains, exhibiting a D60-value of more than 6 min; moderately heat resistant strains, exhibiting a D60-value of more than 1 min; or as heat sensitive. A ~14 kb genomic island containing 16 predicted open reading frames encoding putative heat shock proteins and proteases was identified only in highly heat resistant strains. The genomic island was termed the locus of heat resistance (LHR. This putative operon is flanked by mobile elements and possesses >99% sequence identity to genomic islands contributing to heat resistance in Cronobacter sakazakii and Klebsiella pneumoniae. An additional 41 LHR sequences with >87% sequence identity were identified in 11 different species of β- and γ-proteobacteria. Cloning of the full length LHR conferred high heat resistance to the heat sensitive E. coli AW1.7ΔpHR1 and DH5α. The presence of the LHR correlates perfectly to heat resistance in several species of Enterobacteriaceae and occurs at a frequency of 2% of all E. coli genomes, including pathogenic strains. This study suggests the LHR has been laterally exchanged among the β- and γ-proteobacteria and is a reliable indicator of high heat resistance in E. coli.

  9. Prevalence of antimicrobial resistance in fecal Escherichia coli isolates from stray pet dogs and hospitalized pet dogs in Korea.

    Science.gov (United States)

    Nam, Hyang-Mi; Lee, Hee-Soo; Byun, Jae-Won; Yoon, Soon-Seek; Jung, Suk-Chan; Joo, Yi-Seok; Lim, Suk-Kyung

    2010-03-01

    A total of 628 Escherichia coli isolates recovered from 877 intestinal samples of stray pet dogs (n = 565) and hospitalized pet dogs (n = 312) in Korea were analyzed for resistance to 15 antimicrobial agents. Most common resistance observed in E. coli isolated from both groups of dogs was to tetracycline (52.4-53.6%), streptomycin (35.8-41.7%), ampicillin (32.9-47.1%), nalidixic acid (21.6-37.4%), and trimethoprim/sulfamethoxazole (19.7-36.4%). Resistance to chloramphenicol, gentamicin, and ciprofloxacin was observed in 19.4% (17.1-24.3%), 18% (16.1-21.8%), and 16.1% (13.5-21.4%) of the isolates, respectively. No E. coli isolated from hospitalized dogs showed resistance to imipenem and cefepime, whereas three (0.7%) isolates from stray dogs were resistant to cefepime. Some of the isolates from both groups showed resistance to cefotaxime (2.4-3.9%) and amikacin (0.5-1.5%). In general, the frequency of resistance tended to be higher in isolates from hospitalized dogs than isolates from stray dogs against most antimicrobials tested. Around 39% (162/422) and 27% (55/206) of E. coli isolates from stray dogs and hospitalized dogs were susceptible to all antimicrobials tested, respectively. Multiresistance (> or = 3 subclasses of antimicrobials) was observed in 32% and 48% of E. coli isolates from stray dogs and hospitalized dogs, respectively. More attention should be paid to the use of antimicrobials and the occurrence of antimicrobial resistance in companion animals. PMID:20192822

  10. Molecular Epidemiology of ESBL Genes and Multi-Drug Resistance in Diarrheagenic Escherichia Coli Strains Isolated from Adults in Iran.

    Science.gov (United States)

    Ghorbani-Dalini, Sadegh; Kargar, Mohammad; Doosti, Abbas; Abbasi, Pejman; Sarshar, Meysam

    2015-01-01

    Resistance to oxyimino cephalosporins antibiotics in Enterobacteriaceae is primarily done by the extended spectrum β-lactamases (ESBLs). Clear identification of risk factors for ESBLs-producing infections is necessary. Therefore, efficient strategies can be developed to decrease outbreak of these infections. The aim of this study was to determine the antibacterial susceptibility and ESBLs pattern of diarrhogenic Escherichia coli (E. coli) strains isolated from adult patients. In the present study, diarrheogenic E. coli strains were isolated from 54 patients from the University of Medical Sciences hospitals in Shiraz. Antimicrobial susceptibility testing was done by disk diffusion method by CLSI criteria. The presence of bla TEM , bla SHV and bla CTX-M genes was investigated by PCR using designated primers. The prevalence of ESBLs-producer E. coli strains was 12.96%. Antimicrobial resistance testing showed a high resistance to cefexime, trimethoprim-sulfamethoxazole, ampicillin and penicillin. Overall, β-lactamase genes were identified in 52 (96.30%) isolates which were identified as 45 (83.33%) bla TEM, 17 (31.48%) blaSHV and 11 (20.37%) blaCTX-M. ESBLs-producer E. coli is very prevalent in Diarrheogenic strains isolated from adult patients. Also, this study clearly showed that the bla TEM gene for ESBLs-producer E. coli was widespread in Iran. PMID:26664394

  11. Comparative Research on Serogroups Distribution and Antimicrobial Resistance of Escherichia coil Isolates from Poultry in Different Areas of China

    Institute of Scientific and Technical Information of China (English)

    SONG Li; FENG Zhong-wu; NING Yi-bao; ZHANG Xiu-ying; SHENG Qing-chun; ZHANG Guang-chuan; LIN Shu-mao; WU Hao-ting; ZHAO Hui; GAO Guang

    2008-01-01

    A total of 241 Escherichia coli(E. coli)isolates from 349 avian samples(292 from cloacae,29 from feed and water,28 from dust and padding)were collected from Northeast,South,North,and Central China in recent years.The percentage of isolation was 69.1%.There are 67 serogroups each with 1-2 isolates distributed in different regions.and some of these regions had the preponderant serogroups.Antimicrobial-resistance(AR)of E. coli was so severe that the majority were multi-AR.Fifty percent strains were resistant to 10-19 antimicrobial drugs.Overall,the isolates represented resistance to nalidixic acid(88.1%),tetracycline(85.7%),sulfamethoxazole(81.0%),trimethoprim-sulfamethpxazole(77.1%),ampicillin (76.2%),amoxilline(74.3%),streplomycin(66.2%),fluoroquinolones(57.1-66.7%),chloramphenicol(52.9%),gentamicin (39.0%),and kanamycin(36.2%).The isolates were sensitive to cefalexin,amoxilline-clavulanic acid,amikacin,and florfenicol with all AR rate of 0-19.5%only.The results showed that the AR was more severe in chicken farms in which the antibiotics were used broadly and repeatedly.This study indicated the AR characterization of E. coli in different areas of China.It will be a foundation for studying AR mechanism and regulating the usage of antimicrobial in the poultry industry.

  12. Antimicrobial resistance in Staphylococcus spp., Escherichia coli and Enterococcus spp. in dogs given antibiotics for chronic dermatological disorders, compared with non-treated control dogs

    Directory of Open Access Journals (Sweden)

    Saijonmaa-Koulumies L

    2004-03-01

    Full Text Available The aim of this study was to evaluate antimicrobial resistance in canine staphylococci, Escherichia coli and enterococci, which were isolated from 22 dogs with pyoderma and a history of previous antibiotic treatment, compared to bacterial isolates from 56 non-treated control dogs. Two isolates of each bacterial species per dog were investigated, if detected. Staphylococcal isolates from dogs with pyoderma (35 isolates were more resistant to sulphatrimethoprim than the isolates from controls (56 isolates (57% vs. 25%, p E. coli was detected (24 and 74 isolates from treated and control dogs, respectively, but the differences were not significant. Resistance for macrolide-lincosamides was approximately 20% among staphylococci in both groups. Resistance to ampicillin among enterococci was 4%–7%. The age of the dogs might have an impact on resistance: multiresistance among staphylococcal isolates from younger dogs (≤5 years was more common than in older dogs (≥6 years (24%, vs. 0%, 63 and 27 isolates, respectively, p = 0.02. Staphylococci in younger dogs were more resistant to tetracycline (48% vs. 11%, p E. coli from older dogs tended to be more resistant, although a significant difference was detected only in resistance to tetracycline (13% vs. 2% of 40 and 50 isolates respecthely, p = 0.04. The results of this small study indicate that resistance in canine staphylococci in the capital area of Finland is comparable with many other countries in Europe. Resistance in indicator bacteria, E. coli and enterococci, was low.

  13. Geographical Variation in Antibiotic-Resistant Escherichia coli Isolates from Stool, Cow-Dung and Drinking Water

    Directory of Open Access Journals (Sweden)

    Cecilia Stålsby Lundborg

    2012-03-01

    Full Text Available Little information is available on relationships between the biophysical environment and antibiotic resistance. This study was conducted to investigate the antibiotic resistance pattern of Escherichia coli isolated from child stool samples, cow-dung and drinking water from the non-coastal (230 households and coastal (187 households regions of Odisha, India. Susceptibility testing of E. coli isolates (n = 696 to the following antibiotics: tetracycline, ampicillin/sulbactam, cefuroxime, cefotaxime, cefixime, cotrimoxazole, amikacin, ciprofloxacin, norfloxacin and nalidixic acid was performed by the disk diffusion method. Ciprofloxacin minimum inhibitory concentration (MIC values were determined for ciprofloxacin-resistant isolates (n = 83. Resistance to at least one antibiotic was detected in 90% or more of the E. coli isolates. Ciprofloxacin MIC values ranged from 8 to 32 µg/mL. The odds ratio (OR of resistance in E. coli isolates from children’s stool (OR = 3.1, 95% CI 1.18–8.01, cow-dung (OR = 3.6, 95% CI 1.59–8.03, P = 0.002 and drinking water (OR = 3.8, 95% CI 1.00–14.44, P = 0.049 were higher in non-coastal compared to coastal region. Similarly, the co-resistance in cow-dung (OR = 2.5, 95% CI 1.39–4.37, P = 0.002 and drinking water (OR = 3.2, 95% CI 1.36–7.41, P = 0.008 as well as the multi-resistance in cow-dung (OR = 2.2, 95% CI 1.12–4.34, P = 0.022 and drinking water (OR = 2.7, 95% CI 1.06–7.07, P = 0.036 were also higher in the non-coastal compared to the coastal region.

  14. Increasing antimicrobial resistance in Escherichia coli isolates from community-acquired urinary tract infections during 1998-2003 in Manisa, Turkey.

    Science.gov (United States)

    Kurutepe, Semra; Surucuoglu, Suheyla; Sezgin, Cenk; Gazi, Horu; Gulay, Mehmet; Ozbakkaloglu, Beril

    2005-06-01

    Urinary tract infections are among the most common infections with an increasing resistance to antimicrobials. The aim of this study was to determine the change in antimicrobial susceptibility of Escherichia coli isolates from patients with community-acquired urinary tract infection (UTI) for the years 1998 through 2003 and to suggest that the current empirical antibiotic therapy used for these patients is inappropriate. During the study period, 7,335 community urine samples of which 1,203 (16.4%) grew bacterial isolates were analyzed. Among the total of 1,203 isolates, 880 (73.2%) were E. coli. The range of resistance of E. coli to ampicillin was 47.8 to 64.6% and that to trimethoprim-sulfamethoxazole was 37.1 to 44.6% during the study period. The susceptibility pattern of E. coli to nitrofurantoin and cefuroxime did not vary significantly over the 6-year period. There was a significant increase in the susceptibility of E. coli to ciprofloxacin (11.3 - 26.7%), amoxicillin-clavulanate (18.4 - 29.2%) and gentamicin (7.0 - 25.6%) (P < 0.05). Empirical initial treatment with ampicillin and trimethoprim-sulfamethoxazole was thus inadequate in approximately half of UTI cases in our region. PMID:15973007

  15. Epidemiology, Antimicrobial Resistance and β-lactamase Genotypic Features of Enteropathogenic Escherichia coli Isolated from Children with Diarrhea in Southern China.

    Science.gov (United States)

    Huang, Yong; Shan, Xue-feng; Deng, Haijun; Huang, Yu-jun; Mu, Xiao-ping; Huang, Ai-long; Long, Quan-xin

    2015-01-01

    The main objective of this study was to investigate the epidemiology, drug resistance and β-lactamase genotype distribution of enteropathogenic Escherichia coli (EPEC) isolated from pediatric patients with diarrhea in southern China. The prevalence of EPEC in children with diarrhea was 3.53%. The commonest serotypes were O55:K59 and O126:K71, and the typical EPEC were more prevalent than atypical EPEC (51 vs 7). Isolates from this region were most commonly found to be resistant to ampicillin and cotrimoxazole, followed by chloramphenicol, ceftriaxone, and ceftazidime. More than 96% of the strains were susceptible to cefoperazone/sulbactam and imipenem. The most common β-lactamase genotypes identified in 58 strains were blaCTX-M-1 (60.3%), blaTEM (56.9%), blaCTX-M-9 (27.6%), and blaSHV (15.5%). Among 58 isolates, 22 strains were found to harbor one β-lactamase gene, and the proportions of resistance to ampicillin, cotrimoxazole, chloramphenicol, ceftriaxone, and ceftazidime, were 81.8%, 63.6%, 40.9%, 18.2%, and 9.1%, respectively. A further 30 strains carrying multiple β-lactamase genes had increased resistance to the above antimicrobial agents (100%, 83.3%, 70.0%, 60.0%, and 30.0%, respectively). In contrast, antibiotic resistance in the last 6 strains without a detectable β-lactamase gene was substantially reduced. Drug resistance may be associated with the β-lactamase gene number, with a greater the number of β-lactamase genes resulting in higher antibiotic resistance. PMID:25672408

  16. Characterization of multidrug-resistant Escherichia coli by antimicrobial resistance profiles, plasmid replicon typing, and pulsed-field gel electrophoresis

    Science.gov (United States)

    Aim: Plasmid characterization has particular clinical importance because genes encoding significant traits including antimicrobial resistance are frequently carried on plasmids. The objective of this study was to examine the distribution of multidrug resistance (MDR) in Escherichia coli in relation ...

  17. Antimicrobial activity of peptidomimetics against multidrug-resistant Escherichia coli

    DEFF Research Database (Denmark)

    Jahnsen, Rasmus D; Frimodt-Møller, Niels; Franzyk, Henrik

    2012-01-01

    Novel remedies in the battle against multidrug-resistant bacterial strains are urgently needed, and one obvious approach involves antimicrobial peptides and mimics hereof. The impact of a- and ß-peptoid as well as ß(3)-amino acid modifications on the activity profile against ß......-lactamase-producing Escherichia coli was assessed by testing an array comprising different types of cationic peptidomimetics obtained by a general monomer-based solid-phase synthesis protocol. Most of the peptidomimetics possessed high to moderate activity toward multidrug-resistant E. coli as opposed to the corresponding...... inactive peptides. Nevertheless, differences in hemolytic activities indicate that a careful choice of backbone design constitutes a significant parameter in the search for effective cationic antimicrobial peptidomimetics targeting specific bacteria....

  18. Impact of antibiotic restriction on resistance levels of Escherichia coli

    DEFF Research Database (Denmark)

    Boel, Jonas; Andreasen, Viggo; Jarløv, Jens Otto;

    2016-01-01

    OBJECTIVES: We evaluated the effect of an antibiotic stewardship programme (ASP) on the use of antibiotics and resistance levels of Escherichia coli using a method that allowed direct comparison between an intervention hospital and a control hospital. METHODS: The study was conducted as a...... of E. coli. Results were directly compared with data from the control hospital utilizing a subtracted time series (STS). RESULTS: Direct comparison with the control hospital showed that the ASP was associated with a significant change in the level of use of cephalosporins [-151 DDDs/1000 bed-days (95......% CI -177, -126)] and fluoroquinolones [-44.5 DDDs/1000 bed-days (95% CI -58.9, -30.1)]. Resistance of E. coli showed a significant change in slope for cefuroxime [-0.13 percentage points/month (95% CI -0.21, -0.057)] and ciprofloxacin [-0.15 percentage points/month (95% CI -0.26, -0.038)]. CONCLUSIONS...

  19. The occurrence of antimicrobial resistance and class 1 integrons among commensal Escherichia coli isolates from infants and elderly persons

    Directory of Open Access Journals (Sweden)

    Kõljalg Siiri

    2009-12-01

    Full Text Available Abstract Background The aim of our study was to compare the presence of the intI1 gene and its associations with the antibiotic resistance of commensal Escherichia coli strains in children with/without previous antibiotic treatments and elderly hospitalized/healthy individuals. Methods One-hundred-and-fifteen intestinal E. coli strains were analyzed: 30 strains from 10 antibiotic-naive infants; 27 from 9 antibiotic-treated outpatient infants; 30 from 9 healthy elderly volunteers; and 28 from 9 hospitalized elderly patients. The MIC values of ampicillin, cefuroxime, cefotaxime, gentamicin, ciprofloxacin, and sulfamethoxazole were measured by E-test and IntI1 was detected by PCR. Results Out of the 115 strains, 56 (49% carried class 1 integron genes. Comparing persons without medical interventions, we found in antibiotic-naive children a significantly higher frequency of integron-bearing strains and MIC values than in healthy elderly persons (53% versus 17%; p Conclusion The prevalence of integrons in commensal E. coli strains in persons without previous medical intervention depended on age. The resistance of integron-carrying and non-carrying strains is more dependent on influencing factors (hospitalization and antibiotic administration in particular groups than merely the presence or absence of integrons.

  20. Widespread antibiotic resistance of diarrheagenic Escherichia coli and Shigella species

    Directory of Open Access Journals (Sweden)

    Azam Fatahi Sadeghabadi

    2014-01-01

    Full Text Available Background: Antibiotic resistance of enteric pathogens particularly Shigella species, is a critical world-wide problem and monitoring their resistant pattern is essential, because the choice of antibiotics is absolutely dependent on regional antibiotic susceptibility patterns. During summer 2013, an unusual increase in number of diarrheal diseases was noticed in Isfahan, a central province of Iran. Therefore, the antibiotic resistance of diarrheagenic Escherichia coli and Shigella species isolated were evaluated. Materials and Methods: According to the guideline on National Surveillance System for Foodborn Diseases, random samples from patients with acute diarrhea were examined in local laboratories of health centers and samples suspicious of Shigella spp. were further assessed in referral laboratory. Isolated pathogens were identified by standard biochemical and serologic tests and antibiotic susceptibility testing was carried out by disc diffusion method. Results: A total of 1086 specimens were obtained and 58 samples suspicious of Shigella were specifically evaluated. The most prevalent isolated pathogen was Shigella sonnei (26/58 followed by E. coli (25/58 and Shigella flexneri (3/58. A large number of isolated bacteria were resistant to co-trimoxazole (Shigella spp: 100%, E. coli: 80%, azithromycin (Shigella spp: 70.4%, E. coli: 44.0%, ceftriaxone (Shigella spp: 88.9%, E. coli: 56.0% and cefixime (Shigella spp: 85.2%, E. coli: 68.0%. About88.3% of S. sonnei isolates, one S. flexneri isolate, and 56% of E. coli strains were resistant to at least three antibiotic classes (multidrug resistant. Conclusion: Due to high levels of resistance to recommended and commonly used antibiotics for diarrhea, continuous monitoring of antibiotic resistance seems essential for determining best options of empirical therapy.

  1. Molecular characterization and antibiotic resistance of enterotoxigenic and entero-aggregative Escherichia coli isolated from raw milk and unpasteurized cheeses

    Directory of Open Access Journals (Sweden)

    Mojtaba Bonyadian

    2014-04-01

    Full Text Available The aim of this study was to determine the occurrence of enterotoxigenic and enteroaggregative Escherichia coli strains and antibiotic resistance of the isolates in raw milk and unpasteurized cheese. Out of 200 samples of raw milk and 50 samples of unpasteurized cheeses, 96 and 24 strains of E. coli were isolated, respectively. Polymerase chain reaction (PCR was used to detect the genes encoding heat-stable enterotoxin a (STa, heat-stable enterotoxin b (STb, heat labile toxin (LT and enteroaggregative heat-stable toxin1 (EAST1. Twelve out of 120 (10.00% isolates harbored the gene for EAST1, 2(1.66% isolates were detected as producing STb and LT toxins and 12 (10.00% strains contained STb and EAST1 genes. None of the strains contain the STa gene. All of the strains were tested for antibiotic resistance by disk diffusion method. Disks included: ciprofloxacin (CFN, trimetoprim-sulfamethoxazole (TSX, oxytetracycline (OTC, gentamicin (GMN, cephalexin (CPN, nalidixic acid (NDA and nitrofurantoin (NFN, ampicillin (AMP, neomycin (NEO and streptomycin (STM. Among 120 isolated strains of E. coli, the resistance to each antibiotics were as follows: OTC100%, CPN 86.00%, NDA 56.00%, NFN 42.00%, GMN 30.00%, TSX 28.00%, CFN 20%, AM 23.40% and STM 4.25%. None of the isolates were resistant to NEO. The present data indicate that different resistant E. coli pathogens may be found in raw milk and unpasteurized cheese. It poses an infection risk for human and transferring the resistant factors to microflora of the consumers gut.

  2. First report on rapid screening of nanomaterial-based antimicrobial agents against β-lactamase resistance using pGLO plasmid transformed Escherichia coli HB 101 K-12

    Science.gov (United States)

    Raj, M. Alpha; Muralidhar, Y.; Sravanthi, M.; Prasad, T. N. V. K. V.; Nissipriya, M.; Reddy, P. Sirisha; Neelima, T. Shoba; Reddy, G. Dilip; Adilaxmamma, K.; Kumar, P. Anand; Krishna, T. Giridhara

    2016-08-01

    Combating antibiotic resistance requires discovery of novel antimicrobials effective against resistant bacteria. Herein, we present for the first time, pGLO plasmid transformed Escherichia coli HB 101 K 12 as novel model for screening of nanomaterial-based antimicrobial agents against β-lactamase resistance. E. coli HB 101 was transformed by pGLO plasmid in the presence of calcium chloride (50 mM; pH 6.1) aided by heat shock (0-42-0 °C). The transformed bacteria were grown on Luria-Bertani agar containing ampicillin (amp) and arabinose (ara). The transformed culture was able to grow in the presence of ampicillin and also exhibited fluorescence under UV light. Both untransformed and transformed bacteria were used for screening citrate-mediated nanosilver (CNS), aloin-mediated nanosilver (ANS), 11-α-keto-boswellic acid (AKBA)-mediated nanosilver (BNS); nanozinc oxide, nanomanganese oxide (NMO) and phytochemicals such as aloin and AKBA. Minimum inhibitory concentrations (MIC) were obtained by microplate method using ρ-iodo nitro tetrazolium indicator. All the compounds were effective against transformed bacteria except NMO and AKBA. Transformed bacteria exhibited reverse cross resistance against aloin. ANS showed the highest antibacterial activity with a MIC of 0.32 ppm followed by BNS (10.32 ppm), CNS (20.64 ppm) and NZO (34.83 ppm). Thus, pGLO plasmid can be used to induce resistance against β-lactam antibiotics and the model can be used for rapid screening of new antibacterial agents effective against resistant bacteria.

  3. First report on rapid screening of nanomaterial-based antimicrobial agents against β-lactamase resistance using pGLO plasmid transformed Escherichia coli HB 101 K-12

    Science.gov (United States)

    Raj, M. Alpha; Muralidhar, Y.; Sravanthi, M.; Prasad, T. N. V. K. V.; Nissipriya, M.; Reddy, P. Sirisha; Neelima, T. Shoba; Reddy, G. Dilip; Adilaxmamma, K.; Kumar, P. Anand; Krishna, T. Giridhara

    2015-10-01

    Combating antibiotic resistance requires discovery of novel antimicrobials effective against resistant bacteria. Herein, we present for the first time, pGLO plasmid transformed Escherichia coli HB 101 K 12 as novel model for screening of nanomaterial-based antimicrobial agents against β-lactamase resistance. E. coli HB 101 was transformed by pGLO plasmid in the presence of calcium chloride (50 mM; pH 6.1) aided by heat shock (0-42-0 °C). The transformed bacteria were grown on Luria-Bertani agar containing ampicillin (amp) and arabinose (ara). The transformed culture was able to grow in the presence of ampicillin and also exhibited fluorescence under UV light. Both untransformed and transformed bacteria were used for screening citrate-mediated nanosilver (CNS), aloin-mediated nanosilver (ANS), 11-α-keto-boswellic acid (AKBA)-mediated nanosilver (BNS); nanozinc oxide, nanomanganese oxide (NMO) and phytochemicals such as aloin and AKBA. Minimum inhibitory concentrations (MIC) were obtained by microplate method using ρ-iodo nitro tetrazolium indicator. All the compounds were effective against transformed bacteria except NMO and AKBA. Transformed bacteria exhibited reverse cross resistance against aloin. ANS showed the highest antibacterial activity with a MIC of 0.32 ppm followed by BNS (10.32 ppm), CNS (20.64 ppm) and NZO (34.83 ppm). Thus, pGLO plasmid can be used to induce resistance against β-lactam antibiotics and the model can be used for rapid screening of new antibacterial agents effective against resistant bacteria.

  4. Multicenter evaluation of resistance patterns of Klebsiella pneumoniae, Escherichia coli, Salmonella spp and Shigella spp isolated from clinical specimens in Brazil: RESISTNET surveillance program

    Directory of Open Access Journals (Sweden)

    Carmen Paz Oplustil

    2001-02-01

    Full Text Available Surveillance programs are essential to detect the increase of antimicrobial resistance, and several different programs are being conducted in many countries. The RESISTNET is a surveillance program for bacterial resistance against several antimicrobial agents initiated in 1998 among Latin American countries. In Brazil, several centers were invited to join this surveillance and a total of 11 centers (6 from São Paulo and 5 from other states participated in the study. All results were analyzed using the WHONET program. A total of 894 Escherichia coli, 386 Klebsiella pneumoniae, 70 Shigella spp and 57 Salmonella spp strains were analyzed in this study from April, 1998, to April, 1999. Susceptibility testing was performed by the disk diffusion method using NCCLS 1998 guidelines for several different drugs. For all strains, imipenem was the most effective drug (100% of the strains were susceptible. Klebsiella pneumoniae presented a high resistance rate to ampicillin (96.4%. The rate of probable ESBL producers among K. pneumoniae strains was 36.3%, most of them being isolated from catheters (58.8%. Among all Escherichia coli strains analyzed, the highest resistance rate was found for trimethoprim/sulfamethoxazole (46.9% and the majority of the resistant strains were isolated from urine samples (47.8%. Among Salmonella spp, the resistance rates were low for all antibiotics tested. For Shigella spp strains there was a high resistance to trimethoprim/sulfamethoxazole (80.0%. No resistance to ceftriaxone was observed in these strains. Surveillance of antimicrobial resistance is critical for the successful management of infectious diseases. The results of this survey show significant resistance rates among these bacteria which are responsible for several types of human infections.

  5. Prevalence of Antibiotic Resistance in Escherichia coli Isolated from Poultry Meat Supply in Isfahan

    Directory of Open Access Journals (Sweden)

    Farhad Safarpordehkordi

    2014-08-01

    Conclusions: Despite the high contamination rate of chicken meat with Escherichia coli, majority of isolates had high resistance to common antibiotics. Complete cooking of meat and avoid indiscriminate prescribing of antibiotics, preventing the occurrence of food poisoning due to resistant Escherichia coli.

  6. Heterologously expressed bacterial and human multidrug resistance proteins confer cadmium resistance to Escherichia coli

    OpenAIRE

    Achard-Joris, M; van Saparoea, HBV; Driessen, AJM; Bourdineaud, JP; Bourdineaud, Jean-Paul

    2005-01-01

    The human MDR1 gene is induced by cadmium exposure although no resistance to this metal is observed in human cells overexpressing hMDR1. To access the role of MDR proteins in cadmium resistance, human MDR1, Lactococcus lactis lmrA, and Oenococcus oeni omrA were expressed in an Escherichia coli tolC mutant strain which proved to be hypersensitive to cadmium. Both the human and bacterial MDR genes conferred cadmium resistance to E. coli up to 0.4 mM concentration. Protection was abolished by 10...

  7. Genome Sequences of Two Copper-Resistant Escherichia coli Strains Isolated from Copper-Fed Pigs

    DEFF Research Database (Denmark)

    Lüthje, Freja L.; Hasman, Henrik; Aarestrup, Frank Møller; Alwathnani, Hend A.; Rensing, Christopher

    2014-01-01

    The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances.......The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances....

  8. Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human

    DEFF Research Database (Denmark)

    Shuyu, Wu; Dalsgaard, A.; Hammerum, A. M.; Porsbo, Lone Jannok; Jensen, Lars Bogø

    2010-01-01

    and humans) were 65%, 45% and 12% for sul2, sul1, and sul3, respectively. Transfer of resistance through conjugation was observed in 42/57 isolates. Resistances to streptomycin, ampicillin and trimethoprim were co-transferred in most strains. Class 1 integrons were present in 80% of sul1-carrying...

  9. Prevalence of antimicrobial resistance in enteric Escherichia coli from domestic pets and assessment of associated risk markers using a generalized linear mixed model.

    Science.gov (United States)

    Leite-Martins, Liliana R; Mahú, Maria I M; Costa, Ana L; Mendes, Angelo; Lopes, Elisabete; Mendonça, Denisa M V; Niza-Ribeiro, João J R; de Matos, Augusto J F; da Costa, Paulo Martins

    2014-11-01

    Antimicrobial resistance (AMR) is a growing global public health problem, which is caused by the use of antimicrobials in both human and animal medical practice. The objectives of the present cross-sectional study were as follows: (1) to determine the prevalence of resistance in Escherichia coli isolated from the feces of pets from the Porto region of Portugal against 19 antimicrobial agents and (2) to assess the individual, clinical and environmental characteristics associated with each pet as risk markers for the AMR of the E. coli isolates. From September 2009 to May 2012, rectal swabs were collected from pets selected using a systematic random procedure from the ordinary population of animals attending the Veterinary Hospital of Porto University. A total of 78 dogs and 22 cats were sampled with the objective of isolating E. coli. The animals' owners, who allowed the collection of fecal samples from their pets, answered a questionnaire to collect information about the markers that could influence the AMR of the enteric E. coli. Chromocult tryptone bile X-glucuronide agar was used for E. coli isolation, and the disk diffusion method was used to determine the antimicrobial susceptibility. The data were analyzed using a multilevel, univariable and multivariable generalized linear mixed model (GLMM). Several (49.7%) of the 396 isolates obtained in this study were multidrug-resistant. The E. coli isolates exhibited resistance to the antimicrobial agent's ampicillin (51.3%), cephalothin (46.7%), tetracycline (45.2%) and streptomycin (43.4%). Previous quinolone treatment was the main risk marker for the presence of AMR for 12 (ampicillin, cephalothin, ceftazidime, cefotaxime, nalidixic acid, ciprofloxacin, gentamicin, tetracycline, streptomycin, chloramphenicol, trimethoprim-sulfamethoxazole and aztreonam) of the 15 antimicrobials assessed. Coprophagic habits were also positively associated with an increased risk of AMR for six drugs, ampicillin, amoxicillin

  10. TRENDS IN ANTIMICROBIAL RESISTANCE AMONG UROPATHOGENS WITH SPECIAL REFERENCE TO ESCHERICHIA COLI IN COMMUNITY ACQUIRED PEDIATRIC URINARY TRACT INFECTIONS FROM KERALA

    Directory of Open Access Journals (Sweden)

    Nisha

    2015-07-01

    Full Text Available CONTEXT: Resistance of uropathogens to commonly used antibiotics is increasingly reported from India in adults. There is little data on resistance patterns in childhood community acquired urinary tract infections (UTI. AIMS: To study antibiotic resistanc e trends of uropathogens isolated in community acquired UTI in children from a geographic area. SETTINGS AND DESIGN: Prospective study conducted in a northern Kerala tertiary pediatric centre between November 2012 and October 2014. METHODS : Urine samples were obtained by clean catch midstream, bladder catheterization or supra - pubic aspiration. Bacterial growth, when significant were identified by standard biochemical reactions with antibiogram by Kirby Bauers disc diffusion method. STATISTICAL ANALYSIS : P roportions were calculated and statistical significance obtained by Chi - square. RESULTS : Of the 1387 cultures with suspected community acquired UTI, 274 (19.75% were positive. Mean age of study group was 28.52 months and 64.6% were boys. Escherichia coli (E.coli was the predominant pathogen [189(69%] followed by Klebsiella 50(18.2%. Citrobacter, Enterococcus, Proteus and Pseudomonas constituted less than 6%. All urinary isolates showed high combined resistance to most commonly used antimicrobials inclu ding beta - lactam antibiotics (84.3% to cefotaxime, 83.2% to cefixime, 74.5% to ampicillin, quinolones (54.2% to ciprofloxacin, 46.4% to norfloxacin, 32.8% to levofloxacin, 52.9% to co - trimoxazole, 30.2% to gentamicin, 24.1% to nitrofurantoin and 14.2% to netilmicin. E.coli was highly resistant tocephalosporins and ampicillin (>80%. CONCLUSIONS: There is increasing resistance amongst E.coli coli and Klebsiella to third generation cephalosporins in pediatric age group. It is important to generate regional data on antibiogram pattern to guide therapy.

  11. Physical characterization of plasmids determining synthesis of a microcin which inhibits methionine synthesis in Escherichia coli.

    OpenAIRE

    Perez-Diaz, J C; Clowes, R C

    1980-01-01

    Plasmid deoxyribonucleic acid (DNA) isolated from each of three antibiotic-resistant clinical strains of Escherichia coli producing the same microcin showed multiple bands upon agarose gel electrophoresis. Transformants selected either for microcin resistance or ampicillin resistance yielded plasmid DNA corresponding in size to only one of the multiple bands. Plasmids, isolated from all three hosts, which determined microcin resistance and microcin production measured about 4 megadaltons by s...

  12. Analysis on drug resistance of Escherichia coli resistant to Levofloxacin%耐左氧氟沙星大肠埃希菌的耐药性分析

    Institute of Scientific and Technical Information of China (English)

    游春芳; 周利民; 张肃川; 殷明刚; 伍欢

    2011-01-01

    Objective To investigate the isolated rate of Escherichia coli a-mong Zigong First Peoples' Hospital and analyze the drug resistance of strains resistant to Levofloxacin. Methods Kirby-Bauer' s detection technique was applied to detect the resistance feature in 154 strains of Escherichia coli collected from August 2009 to August 2010. Results Total of 76 strains resisted to Levofloxacin were detected in 154 strains of Escherichia coli, with the detection rate as 49.35%. Among the specimens, the isolated rate of strains resistant to Levofloxacin in urina was the highest (51. 32% ) and the second was in sputum ( 23. 68% ). Except for imipenem, mlopen-em, cefoxitin, piperacillin/tazobatan and amikacin, the resistance rate of Levofloxa-cin-resistant strains were significantly higher than that of non-Levofloxacin-resistant strains to ampicillin, cefazolin, cefepime, cefotaxime, ceftazidime, gentamycin, cef-operazone/sulbactam ( P < 0. 05 ). Conclusions Levofloxacin-resistant Escherichia coli is resistant to many antibacterial agents. Monitoring of Levofloxacin-resistantstrains should be strengthened and the indication of antibiotics must be mastered strictly to prevent the dissemination of drug resistant strains.%目的 了解本院临床分离的大肠埃希菌的耐药情况,分析耐左氧氟沙星细菌的耐药性.方法 对2009年8月至2010年8月本院临床分离的154株大肠埃希菌用Kirby-Bauer琼脂扩散法进行药物敏感试验.结果 154株大肠埃希菌中共检出耐左氧氟沙星菌76株,检出率49.35%.在各类标本中,尿液中耐左氧氟沙星菌株分离率最高(51.32%),其次为痰(23.68%).除亚胺培南、美罗培南、头孢西丁、哌拉西林/他唑巴坦和阿米卡星外,耐左氧氟沙星菌株对氨苄西林、头孢唑啉、头孢吡肟、头孢噻肟、头孢他啶、庆大霉素、头孢哌酮/舒巴坦的耐药率明显高于非耐左氧氟沙星菌株(P< 0.05).结论 本院耐左氧氟沙星大肠埃希菌株对多种

  13. Frequency of escherichia coli in patients with community acquired urinary tract infection and their resistance pattern against some commonly used anti bacterials

    International Nuclear Information System (INIS)

    Urinary tract infection (UTI) is a very common health problem and Escherichia coli (E coli) are the most common organisms associated with community acquired UTI. Unfortunately these bacteria have developed extensive resistance against most of the commonly used anti-bacterials. The objective of this study was to determine the frequency and resistance pattern of E coli in patients of community acquired UTI in an area in northern part of Pakistan. Methods: Urine specimens were collected from patients who were clinically diagnosed as community acquired UTI. Urine routine examination (Urine RE) was done and samples positive for UTI (Pus cells >10/High Power Field) were included in the study. These samples were inoculated on Eosin Methylene Blue (EMB) agar plates and incubated at 37 degree C for 36 hours. Suspected colonies were then inoculated further on EMB plates for pure cultures of E coli characterized by certain morphological characteristics. IMViC was applied for the confirmation of E coli. In vitro antibiotic susceptibility tests of E coli were performed with standardized commercial susceptibility discs (OXOID). Results: Out of 50 specimens, positive for UTI by urine RE, 20 showed pure growth of E coli on culture (40%). The majority of the isolates (28%; n=14) were from women while only 12% (n=6) were from men. Escherichia coli showed a high rate of resistance towards Ampicillin (90%), Tetracycline (70%), Erythromycin (70%) and Trimethoprim-Sulfamethoxazole (55%). Sparfloxacin showed better results (45%) than ciprofloxacin (50%). Out of 20 E coli isolates, two (10%) were resistant to all the antibacterials except chloramphenicol, eight isolates (40%) showed resistance to six or more than six while 14 (70%) were resistant to four or more than four drugs. Conclusion: Rate of resistance of E coli against commonly used antibacterials was quite high and majority of the strains showed multidrug resistance. (author)

  14. Prevalence of antimicrobial resistance and integrons in Escherichia Coli from Punjab, Pakistan

    Directory of Open Access Journals (Sweden)

    Idrees Muhammad

    2011-06-01

    Full Text Available Antimicrobial resistance was studied in Escherichia coli strains isolated from urine samples of 457 patients suffering from urinary tract infection. High prevalence of class 1 integrons (43.56%, sulfamethoxazole resistance genes sul1 (45.54% and sul2 (51.48% along with occurrence of quinolone resistance genes was detected in multi drug resistance isolates.

  15. Determination of extended spectrum β-lactamases/AmpC β-lactamases and plasmid-mediated quinolone resistance in Escherichia coli isolates obtained from bovine carcasses in Mexico.

    Science.gov (United States)

    Aguilar-Montes de Oca, Saúl; Talavera-Rojas, Martín; Soriano-Vargas, Edgardo; Barba-León, Jeannette; Vazquez-Navarrete, Jesús

    2015-06-01

    Food-borne bacterial infections have worldwide importance, and a great variety of antibiotic resistance mechanisms, mainly of the chromosome type, have rapidly developed. Antimicrobial resistance was determined in this study in terms of the presence of extended-spectrum β-lactamases (ESBLs), plasmid AmpC β-lactamases (pAmpC), and plasmid-mediated quinolone resistance (PMQR) from 155 Escherichia coli isolates obtained from bovine carcasses from two states in Mexico (states of Mexico and Jalisco). Isolates were challenged with β-lactam antimicrobials (ampicillin, ceftazidime, and cefotaxime) and quinolones (nalidixic acid and ciprofloxacin). The presence of the bla TEM, bla SHV, bla CTX-M, bla OXA , bla CMY, bla MOX, bla LAT, bla BIL, qnrA, qnrB, qnrS, aac(6')-Ib-cr, and qepA genes was examined by PCR. Clonal relationship was determined using pulsed-field gel electrophoresis (PFGE). The highest resistance was found to be to nalidixic acid (64 %), followed by ampicillin (32 %), ciprofloxacin (10 %), and ceftazidime and cefotaxime (both 1.3 %). bla CMY (n = 1), bla TEM (n = 24), qnrB (n = 9), and qnrS (n = 7) genes were detected. PFGE analysis showed that the majority of isolates had a different genotypic profile. To our knowledge, this is the first report of the presence of the qnrB, qnrS, and bla CMY genes in E. coli isolated from bovine meat in Mexico. PMID:25894820

  16. Bacterial strains isolated from eggs and their resistance to currently used antibiotics: is there a health hazard for consumers?

    Science.gov (United States)

    Papadopoulou, C; Dimitriou, D; Levidiotou, S; Gessouli, H; Panagiou, A; Golegou, S; Antoniades, G

    1997-01-01

    In order to study the putative transfer of antibiotic resistance from poultry to humans, hens' eggs were examined for the presence of various pathogens. Staphylococcus, Enterobacter, Escherichia, Proteus and Pseudomonas spp. were the most frequently isolated genera. Sensitivity tests, performed with the Kirby-Bauer technique, showed the presence of resistant strains of Staphylococcus aureus (to penicillin-G, tetracycline, erythromycin, clindamycin, cefalosporins, oxacillin, gentamycin, chloramphenicol and tobramycin), Enterococcus faecalis (to ampicillin, ciprofloxacin, clindamycin, gentamycin and tetracyclin), Escherichia coli (to tetracycline, erythromycin, ampicillin and cefalosporins), Enterobacter cloacae (to ampicillin, amoxycillin plus clavunalic acid, erythromycin and tetracycline), Pseudomonas stutzeri (to erythromycin and chlorampenicol) and Citrobacter freundii (to ampicillin, amoxycillin plus clavunalic acid, cefalosporins and co-trimoxazole). PMID:9023039

  17. The gold/ampicillin interface at the atomic scale

    Science.gov (United States)

    Tarrat, N.; Benoit, M.; Giraud, M.; Ponchet, A.; Casanove, M. J.

    2015-08-01

    In the fight against antibiotic resistance, gold nanoparticles (AuNP) with antibiotics grafted on their surfaces have been found to be potent agents. Ampicillin-conjugated AuNPs have been thus reported to overcome highly ampicillin-resistant bacteria. However, the structure at the atomic scale of these hybrid systems remains misunderstood. In this paper, the structure of the interface between an ampicillin molecule AMP and three flat gold facets Au(111), Au(110) and Au(100) has been investigated with numerical simulations (dispersion-corrected DFT). Adsorption energies, bond distances and electron densities indicate that the adsorption of AMP on these facets goes through multiple partially covalent bonding. The stability of the AuNP/AMP nanoconjugates is explained by large adsorption energies and their potential antibacterial activity is discussed on the basis of the constrained spatial orientation of the grafted antibiotic.In the fight against antibiotic resistance, gold nanoparticles (AuNP) with antibiotics grafted on their surfaces have been found to be potent agents. Ampicillin-conjugated AuNPs have been thus reported to overcome highly ampicillin-resistant bacteria. However, the structure at the atomic scale of these hybrid systems remains misunderstood. In this paper, the structure of the interface between an ampicillin molecule AMP and three flat gold facets Au(111), Au(110) and Au(100) has been investigated with numerical simulations (dispersion-corrected DFT). Adsorption energies, bond distances and electron densities indicate that the adsorption of AMP on these facets goes through multiple partially covalent bonding. The stability of the AuNP/AMP nanoconjugates is explained by large adsorption energies and their potential antibacterial activity is discussed on the basis of the constrained spatial orientation of the grafted antibiotic. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03318g

  18. Pharmacodynamics of ampicillin sodium transdermal patches in an in vitro infection model

    OpenAIRE

    Bagyalakshmi J; William A; Mithun A; Ravi T; Manavalan R; Manna P

    2006-01-01

    The purpose of this study was to examine the activity of ampicillin sodium developed as transdermal patch against Escherichia coli . In the present work, the efficiency of ampicillin sodium against E. coli was investigated in an in vitro infection model which simulates human pharmacokinetics. The E. coli stains were exposed to transdermal patch with different kinds of polymers such as sodium alginate, cellulose acetate phthalate, hydroxypropylmethylcellulose, chitosan and carboxymethyl...

  19. Escherichia coli antibiotic resistance in emergency departments. Do local resistance rates matter?

    Science.gov (United States)

    Grignon, O; Montassier, E; Corvec, S; Lepelletier, D; Hardouin, J-B; Caillon, J; Batard, E

    2015-03-01

    Ciprofloxacin and cotrimoxazole are recommended to treat uncomplicated pyelonephritis and uncomplicated cystitis, respectively, provided that local resistance rates of uropathogens do not exceed specified thresholds (10 and 20 %, respectively). However, Escherichia coli resistance rates in Emergency Departments (ED) remain poorly described. Our objectives were to assess E. coli ciprofloxacin and cotrimoxazole resistance rates in EDs of a French administrative region, and to determine if resistance rates differ between EDs. This was a retrospective study of E. coli urine isolates sampled in ten EDs between 2007 and 2012. The following risk factors for resistance were tested using logistic regression: ED, sex, age, sampling year, sampling month. A total of 17,527 isolates were included. Ciprofloxacin local resistance rates (range, 5.3 % [95 % CI, 4.0-7.1 %] to 11.7 % [95 % CI, 5.2-23.2 %]) were ≤10 % in nine EDs in 2012. Five EDs were risk factors for ciprofloxacin resistance, as were male sex, age and sampling in April or October. Cotrimoxazole local resistance rates (range, 13.3 % [95 % CI, 6.3-25.1 %] to 20.4 % [95 % CI, 18.9-22.0 %]) were ≤20 % in seven EDs in 2012. Five EDs were risk factors for cotrimoxazole resistance, as were age, sampling between October and December, and sampling in 2011 and 2012. We found a significant variability of E. coli ciprofloxacin and cotrimoxazole resistance rates among EDs of a small region. These differences impact on the feasibility of empirical treatment of urinary tract infections with ciprofloxacin or cotrimoxazole in a given ED. Continuous local survey of antibacterial resistance in ED urinary isolates is warranted to guide antibacterial therapy of urinary tract infections. PMID:25339200

  20. Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran

    OpenAIRE

    Reza Talebiyan; Mehdi Kheradmand; Faham Khamesipour; Mohammad Rabiee-Faradonbeh

    2014-01-01

    Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88....

  1. Plasmid profiling of multidrug resistant Escherichia coli strains isolated from urinary tract infection patients

    OpenAIRE

    Sabin Khadgi; Uddhav Timilsina; Basudha Shrestha

    2013-01-01

    Introduction- Urinary tract infection is a common community-acquired bacterial disease. Escherichia coli is reported to be the major cause of urinary tract infection. Aim & Objective- The study was conducted with the aim of determining the antibiotic resistance pattern and plasmid profile of multidrug resistant Escherichia coli isolated from Urinary Tract Infection patients. Materials and Method- Antibiotic susceptibility tests were performed against E. coli following the protocol for the Kir...

  2. Antimicrobial resistance in Staphylococcus spp., Escherichia coli and Enterococcus spp. in dogs given antibiotics for chronic dermatological disorders, compared with non-treated control dogs.

    Science.gov (United States)

    Rantala, M; Lahti, E; Kuhalampil, J; Pesonen, S; Järvinen, A K; Saijonmaa-Koulumies; Honkanen-Buzalski, T

    2004-01-01

    The aim of this study was to evaluate antimicrobial resistance in canine staphylococci, Escherichia coli and enterococci, which were isolated from 22 dogs with pyoderma and a history of previous antibiotic treatment, compared to bacterial isolates from 56 non-treated control dogs. Two isolates of each bacterial species per dog were investigated, if detected. Staphylococcal isolates from dogs with pyoderma (35 isolates) were more resistant to sulphatrimethoprim than the isolates from controls (56 isolates) (57% vs. 25%, p < 0.004). Multiresistance in staphylococci was also more common in dogs with pyoderma (29% vs. 9%, p = 0.02). A similar trend among isolates of E. coli was detected (24 and 74 isolates from treated and control dogs, respectively), but the differences were not significant. Resistance for macrolide-lincosamides was approximately 20% among staphylococci in both groups. Resistance to ampicillin among enterococci was 4%-7%. The age of the dogs might have an impact on resistance: multiresistance among staphylococcal isolates from younger dogs (< or = 5 years) was more common than in older dogs (26 years) (24%, vs. 0%, 63 and 27 isolates, respectively, p = 0.02). Staphylococci in younger dogs were more resistant to tetracycline (48% vs. 11%, p < 0.001) and sulphatrimethoprim (48% vs. 15%, p < 0.01) than those in older dogs. In contrast, the isolates of E. coli from older dogs tended to be more resistant, although a significant difference was detected only in resistance to tetracycline (13% vs. 2% of 40 and 50 isolates respecthely, p = 0.04)). The results of this small study indicate that resistance in canine staphylococci in the capital area of Finland is comparable with many other countries in Europe. Resistance in indicator bacteria, E. coli and enterococci, was low. PMID:15535085

  3. Prevalence of veterinary antibiotics and antibiotic-resistant Escherichia coli in the surface water of a livestock production region in northern China.

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    Xuelian Zhang

    Full Text Available This study investigated the occurrence of 12 veterinary antibiotics (VAs and the susceptibility of Escherichia coli (E. coli in a rural water system that was affected by livestock production in northern China. Each of the surveyed sites was determined with at least eight antibiotics with maximum concentration of up to 450 ng L(-1. The use of VAs in livestock farming probably was a primary source of antibiotics in the rivers. Increasing total antibiotics were measured from up- to mid- and downstream in the two tributaries. Eighty-eight percent of the 218 E. coli isolates that were derived from the study area exhibited, in total, 48 resistance profiles against the eight examined drugs. Significant correlations were found among the resistance rates of sulfamethoxazole-trimethoprim, chloromycetin and ampicillin as well as between tetracycline and chlortetracycline, suggesting a possible cross-selection for resistance among these drugs. The E. coli resistance frequency also increased from up- to midstream in the three rivers. E. coli isolates from different water systems showed varying drug numbers of resistance. No clear relationship was observed in the antibiotic resistance frequency with corresponding antibiotic concentration, indicating that the antibiotic resistance for E. coli in the aquatic environment might be affected by factors besides antibiotics. High numbers of resistant E. coli were also isolated from the conserved reservoir. These results suggest that rural surface water may become a large pool of VAs and resistant bacteria. This study contributes to current information on VAs and resistant bacteria contamination in aquatic environments particularly in areas under intensive agriculture. Moreover, this study indicates an urgent need to monitor the use of VAs in animal production, and to control the release of animal-originated antibiotics into the environment.

  4. Detection of ampicillin, its sodium salt and alkaline hydrolysis products by MALDI-TOF Mass Spectrometry

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    Lukáš Hleba

    2016-05-01

    Full Text Available Antibiotic resistance of bacteria is very big problem in clinical and veterinary medicine in recent year. This problem is increasing by the exposure of bacteria against antibiotics. The most spread of resistance is resistance against penicillins antibiotics. Ampicillin is common use antibiotic in the both medicine. Therefore, detection of antibiotics and antibiotic resistance are very important for prevention of spread of antibiotics in the environment and resistant bacteria too. Therefore the aim of this study was detection of ampicillin, its sodium salts and alkaline hydrolysis products by MALDI-TOF Mass Spectrometry. For detection of pure ampicillin, its sodium salts and alkaline hydrolysed products MALDI-TOF MS (Matrix Assisted Light Desorption Ionization – Time of Flight Mass Spectrometry Microflex LT in positive ion mode was used. Determined mass spectra were observed by FlexAnalysis software. The mass spectra and molecular weight of ampicillin, its sodium salts and hydrolysed products were compared with theoretical molecular weight of these compounds. The results showed that its possible to detect ampicillin, its sodium salts and hydrolyzed products by MALDI-TOF MS in positive ion mode with some correction in analytical software. This knowledge is resulting that MALDI-TOF MS detection method can be useful for detection of ampicillin from different kind of environment samples and its possible to detect ampicillin resistance mechanism (enzymatic destruction indirectly, because resistance against penicillins is enzymatic hydrolysis of beta-lactam core. Also the most important issue is that method is very quickly and cheap.

  5. Comparison of ampicillin-sulbactam with vancomycin for treatment of experimental endocarditis due to a beta-lactamase-producing, highly gentamicin-resistant isolate of Enterococcus faecalis.

    OpenAIRE

    Lavoie, S R; Wong, E S; Coudron, P E; Williams, D S; Markowitz, S M

    1993-01-01

    Increasing antibiotic resistance in the enterococci, including the capacity for beta-lactamase production and the development of high-level aminoglycoside resistance, has complicated the treatment of serious enterococcal infections, which often require synergistic antibiotic combinations for cure. We utilized the rabbit model of aortic valve endocarditis to investigate the effects of various antibiotics, alone and in combination, against a multiply antibiotic-resistant isolate of Enterococcus...

  6. Resistencia a antimicrobianos en aislamientos de Escherichia coli de origen animal Antimicrobial resistance of Escherichia coli isolated from animals

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    G. Carloni

    2011-12-01

    Full Text Available Se determinó el perfil de susceptibilidad a antimicrobianos de 100 aislamientos de E.coli provenientes de diversas patologías en bovinos, equinos, caninos y felinos, siguiendo metodología del Clinical and Laboratory Standards Institute y detectando la aparición de aislamientos multiresistentes. El panel de antibióticos ensayados incluyó amicacina, ampicilina/sulbactama, cefotaxima, ciprofloxacina, cloranfenicol, colistina, estreptomicina, gentamicina, nitrofurantoína, tetraciclina, trimetoprima/ sulfametoxazol. El mayor porcentaje de resistencia (R se detectó frente a tetraciclina en aislamientos de todas las especies animales (entre 34% en los de origen felino y 75% de origen equino. En las cepas de origen canino y felino se encontraron porcentajes considerables frente ampicilina/ sulbactama (27% de caninos y 53% de felinos y ante ciprofloxacina (30% y 67% respectivamente. En estos aislamientos también, se detectó el mayor porcentaje de multiresistencia (29% en caninos y 67% en felinos. La presión selectiva originada por la aplicación inadecuada de antibióticos puede resultar un factor, aunque no el único, responsable de la aparición de R. Además existe la posibilidad de que E.coli pueda constituirse en un eslabón de transmisión de genes de R a antimicrobianos, aunque no se conoce hasta el momento, el origen de ellos, humano o animal y, su permanencia en el tiempo.Antimicrobial susceptibility tests were determined in 100 isolates of E.coli from differents patologies in cattle, horses, dogs and cats, according to Clinical and Laboratory Standards Institute. Multiresistance isolates were detected in this assay. The antibiotics selected were amikacin, ampicillin /sulbactam, cefotaxime, ciprofloxacin, chloramphenicol, colistin, gentamicin, nitrofurantoin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole. The antibiotic with the highest resistance was tetracycline (34% in cats and 75% in dogs. In isolated strains from dogs

  7. Multidrug-Resistant and Extended Spectrum Beta-Lactamase-Producing Escherichia coli in Dutch Surface Water and Wastewater.

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    Hetty Blaak

    Full Text Available The goal of the current study was to gain insight into the prevalence and concentrations of antimicrobial resistant (AMR Escherichia coli in Dutch surface water, and to explore the role of wastewater as AMR contamination source.The prevalence of AMR E. coli was determined in 113 surface water samples obtained from 30 different water bodies, and in 33 wastewater samples obtained at five health care institutions (HCIs, seven municipal wastewater treatment plants (mWWTPs, and an airport WWTP. Overall, 846 surface water and 313 wastewater E. coli isolates were analysed with respect to susceptibility to eight antimicrobials (representing seven different classes: ampicillin, cefotaxime, tetracycline, ciprofloxacin, streptomycin, sulfamethoxazole, trimethoprim, and chloramphenicol.Among surface water isolates, 26% were resistant to at least one class of antimicrobials, and 11% were multidrug-resistant (MDR. In wastewater, the proportions of AMR/MDR E. coli were 76%/62% at HCIs, 69%/19% at the airport WWTP, and 37%/27% and 31%/20% in mWWTP influents and effluents, respectively. Median concentrations of MDR E. coli were 2.2×10(2, 4.0×10(4, 1.8×10(7, and 4.1×10(7 cfu/l in surface water, WWTP effluents, WWTP influents and HCI wastewater, respectively. The different resistance types occurred with similar frequencies among E. coli from surface water and E. coli from municipal wastewater. By contrast, among E. coli from HCI wastewater, resistance to cefotaxime and resistance to ciprofloxacin were significantly overrepresented compared to E. coli from municipal wastewater and surface water. Most cefotaxime-resistant E. coliisolates produced ESBL. In two of the mWWTP, ESBL-producing variants were detected that were identical with respect to phylogenetic group, sequence type, AMR-profile, and ESBL-genotype to variants from HCI wastewater discharged onto the same sewer and sampled on the same day (A1/ST23/CTX-M-1, B23/ST131/CTX-M-15, D2/ST405/CTX-M-15.In

  8. Antibiotic resistance profiles of Escherichia coli isolated from different water sources in the Mmabatho locality, Northwest Province, South Africa

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    C. Njie Ateba

    2010-03-01

    Full Text Available The antibiotic resistance profiles of Escherichia coli (E. coli, isolated from different water sources in the Mmabatho locality were evaluated. Water samples were collected from the local wastewater- and water-treatment plants, the Modimola Dam and homes in the area, and then analysed for the presence of E. coli, using standard methods. Presumptive isolates obtained were confirmed by the analytical profile index test. Antibiotic susceptibility testing was performed by the disc diffusion method. Of the 230 E. coli isolates tested, marked antibiotic resistances (over 70% were observed for erythromycin, tetracycline, ampicillin, chloramphenicol and norfloxacin. Multiple antibiotic resistance patterns were also compiled. Overall, the phenotype T-Ap-E was frequent for E. coli isolated from the local wastewater and water-treatment plants, Modimola Dam and tap water. Cluster analysis performed showed a unique antibiotic resistance pattern which suggested a link between isolates from all sampling points. The findings indicated that improper wastewater treatment may have a potential impact on the dissemination and survival of E. coli, as well as other pathogenic bacteria in water for human and animal consumption. This may result in water- and food-borne disease outbreaks with a negative effect on antibiotic therapy.

  9. QUINOLONE- AND ETA-LACTAM- RESISTANCE IN Escherichia coli FROM DANISH AND ITALIAN BROILER FLOCKS

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    M. Trevisani

    2009-03-01

    Full Text Available The prevalence of quinolone- and -lactam-resistant E. coli was investigated among healthy broiler flocks in Denmark and Italy. In Denmark, sock samples were collected from 10 parent flocks and 10 offspring flocks, according to the procedure currently used for the surveillance of Salmonella in the EU. Samples were enriched in McConkey broth and streaked on McConkey agar plates added with nalidixic acid (32 g/ml, ciprofloxacin (2 g/ml, ampicillin (32 g/ml, cefotaxime (2 g/ml or ceftiofur (8 g/ml. The -glucuronidase test was performed for verification of presumptive E. coli. The same methods were used to analyse sock samples collected from 6 Italian broiler flocks. PCR with primers for the CTX-M-type extended-spectrum -lactamases (ESBLs was performed on cephalosporin-resistant isolates. While resistance to ampicillin and nalidixic acid was widespread in both countries, resistance to ciprofloxacin and cephalosporins was more common among Italian flocks. In Denmark, ciprofloxacin resistance was only detected in 1 parent flock without any history of quinolone usage and none of the flocks was positive for cephalosporin-resistant E. coli. In Italy, resistance to ciprofloxacin was detected in all flocks and resistance to ceftiofur and cefotaxime were detected in 5 flocks. Primers specific for the CTX-M-type ESBLs generated PCR amplicons from isolates from 3 of these flocks. In industrialized countries, the poultry production system is highly standardized, and therefore comparable. However, the use of broad-spectrum antimicrobials is particularly limited in Danish poultry production. Accordingly, the results of this study could reflect the different policies in antimicrobial usage between the two countries.

  10. Population dynamics of transgenic strain Escherichia coli Z905/pPHL7 in freshwater and saline lake water microcosms with differing microbial community structures

    Science.gov (United States)

    Popova, L. Yu.; Kargatova, T. V.; Ganusova, E. E.; Lobova, T. I.; Boyandin, A. N.; Mogilnaya, O. A.; Pechurkin, N. S.

    Populations of Escherichia coli Z905/pPHL7, a transgenic microorganism, were heterogenic in the expression of plasmid genes when adapting to the conditions of water microcosms of various mineralization levels and structure of microbial community. This TM has formed two subpopulations (ampicillin-resistant and ampicillin-sensitive) in every microcosm. Irrespective of mineralization level of a microcosm, when E. coli Z905/pPHL7 alone was introduced, the ampicillin-resistant subpopulation prevailed, while introduction of the TM together with indigenous bacteria led to the dominance of the ampicillin-sensitive subpopulation. A high level of lux gene expression maintained longer in the freshwater microcosms than in sterile saline lake water microcosms. A horizontal gene transfer has been revealed between the jointly introduced TM and Micrococcus sp. 9/pSH1 in microcosms with the Lake Shira sterile water.

  11. Ciprofloxacin-resistant Escherichia coli in Central Greece: mechanisms of resistance and molecular identification

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    Mavroidi Angeliki

    2012-12-01

    Full Text Available Abstract Background Fluoroquinolone resistant E. coli isolates, that are also resistant to other classes of antibiotics, is a significant challenge to antibiotic treatment and infection control policies. In Central Greece a significant increase of ciprofloxacin-resistant Escherichia coli has occurred during 2011, indicating the need for further analysis. Methods A total of 106 ciprofloxacin-resistant out of 505 E. coli isolates consecutively collected during an eight months period in a tertiary Greek hospital of Central Greece were studied. Antimicrobial susceptibility patterns and mechanisms of resistance to quinolones were assessed, whereas selected isolates were further characterized by multilocus sequence typing and β-lactamase content. Results Sequence analysis of the quinolone-resistance determining region of the gyrA and parC genes has revealed that 63% of the ciprofloxacin-resistant E. coli harbored a distinct amino acid substitution pattern (GyrA:S83L + D87N; ParC:S80I + E84V, while 34% and 3% carried the patterns GyrA:S83L + D87N; ParC:S80I and GyrA:S83L + D87N; ParC:S80I + E84G respectively. The aac (6’-1b-cr plasmid-mediated quinolone resistance determinant was also detected; none of the isolates was found to carry the qnrA, qnrB and qnrS. Genotyping of a subset of 35 selected ciprofloxacin-resistant E. coli by multilocus sequence typing has revealed the presence of nine sequence types; ST131 and ST410 were the most prevalent and were exclusively correlated with hospital and health care associated infections, while strains belonging to STs 393, 361 and 162 were associated with community acquired infections. The GyrA:S83L + D87N; ParC:S80I + E84V substitution pattern was found exclusively among ST131 ciprofloxacin-resistant E. coli. Extended-spectrum β-lactamase-positive ST131 ciprofloxacin-resistant isolates produced CTX-M-type enzymes; eight the CTX-M-15 and one the CTX-M-3 variant. CTX-M-1 like and KPC-2 enzymes were detected

  12. Identification of Diverse Antimicrobial Resistance Determinants Carried on Bacterial, Plasmid, or Viral Metagenomes from an Activated Sludge Microbial Assemblage▿

    OpenAIRE

    Parsley, Larissa C.; Consuegra, Erin J.; Kakirde, Kavita S.; Land, Andrew M.; Harper, Willie F.; Liles, Mark R.

    2010-01-01

    Using both sequence- and function-based metagenomic approaches, multiple antibiotic resistance determinants were identified within metagenomic libraries constructed from DNA extracted from bacterial chromosomes, plasmids, or viruses within an activated sludge microbial assemblage. Metagenomic clones and a plasmid that in Escherichia coli expressed resistance to chloramphenicol, ampicillin, or kanamycin were isolated, with many cloned DNA sequences lacking any significant homology to known ant...

  13. Effects of Halides on Plasmid-Mediated Silver Resistance in Escherichia coli

    OpenAIRE

    Gupta, Amit; Maynes, Maria; Silver, Simon

    1998-01-01

    Silver resistance of sensitive Escherichia coli J53 and resistance plasmid-containing J53(pMG101) was affected by halides in the growth medium. The effects of halides on Ag+ resistance were measured with AgNO3 and silver sulfadiazine, both on agar and in liquid. Low concentrations of chloride made the differences in MICs between sensitive and resistant strains larger. High concentrations of halides increased the sensitivities of both strains to Ag+.

  14. Molecular characterization of vancomycin-resistant enterococci and extended-spectrum β-lactamase-containing Escherichia coli isolates in wild birds from the Azores Archipelago.

    Science.gov (United States)

    Silva, Nuno; Igrejas, Gilberto; Rodrigues, Pedro; Rodrigues, Tiago; Gonçalves, Alexandre; Felgar, Ana Carolina; Pacheco, Rui; Gonçalves, David; Cunha, Regina; Poeta, Patrícia

    2011-10-01

    To study the prevalence of vancomycin-resistant enterococci (VRE) and extended-spectrum β-lactamase (ESBL)-containing Escherichia coli isolates, and the mechanisms of resistance implicated, 220 faecal samples from wild birds were collected between 2006 and 2010 in the Azores Archipelago. Samples were spread on Slanetz-Bartley agar plates supplemented with 4 mg/l vancomycin and on Levine agar plates supplemented with 2 mg/l cefotaxime for VRE and ESBL-containing E. coli isolation, respectively. vanA-containing enterococcal isolates (four Enterococcus faecium and two Enterococcus durans) and vanC-1 Enterococcus gallinarum isolates were detected in six and seven faecal samples, respectively. VRE isolates showed ampicillin (n=11), ciprofloxacin (n=9), tetracycline (n=6), erythromycin (n=5), quinupristin/dalfopristin (n=3) and high-level kanamycin resistance (n=1). The tet(L) and/or tet(M) gene was found in all tetracycline-resistant isolates and the erm(B) gene in all erythromycin-resistant isolates. Three vanA-containing E. faecium and two E. gallinarum presented specific sequences of the Tn5397 transposon. Four VRE isolates harboured the ace virulence gene. One faecal sample revealed one ESBL-containing E. coli isolate that belongs to the A phylogenetic group, showed a phenotype of resistance to β-lactams and tetracycline, and harboured the bla (CTX-M-14), bla (SHV-12) and the tet(A) genes. To our knowledge, this is the first study to focus on defining the prevalence of VRE and/or ESBL-containing E. coli strains in wild birds from the Azores. The data recovered are essential to improve knowledge about the dissemination of resistant strains through wild ecosystems and their possible implications by transferring these resistances to other animals or to humans. PMID:21834624

  15. Characterization of Escherichia coli Isolates from an Urban Lake Receiving Water from a Wastewater Treatment Plant in Mexico City: Fecal Pollution and Antibiotic Resistance.

    Science.gov (United States)

    Rosas, Irma; Salinas, Eva; Martínez, Leticia; Cruz-Córdova, Ariadnna; González-Pedrajo, Bertha; Espinosa, Norma; Amábile-Cuevas, Carlos F

    2015-10-01

    The presence of enteric bacteria in water bodies is a cause of public health concerns, either by directly causing water- and food-borne diseases, or acting as reservoirs for antibiotic resistance determinants. Water is used for crop irrigation; and sediments and aquatic plants are used as fertilizing supplements and soil conditioners. In this work, the bacterial load of several micro-environments of the urban lake of Xochimilco, in Mexico City, was characterized. We found a differential distribution of enteric bacteria between the water column, sediment, and the rhizoplane of aquatic plants, with human fecal bacteria concentrating in the sediment, pointing to the need to assess such bacterial load for each micro-environment, for regulatory agricultural purposes, instead of only the one of the water, as is currently done. Resistance to tetracycline, ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole was common among Escherichia coli isolates, but was also differentially distributed, being again higher in sediment isolates. A distinct distribution of chloramphenicol minimum inhibitory concentrations (MIC) among these isolates suggests the presence of a local selective pressure favoring lower MICs than those of isolates from treated water. Fecal bacteria of human origin, living in water bodies along with their antibiotic resistance genes, could be much more common than typically considered, and pose a higher health risk, if assessments are only made on the water column of such bodies. PMID:26198413

  16. Antimicrobial Resistance, Extended-Spectrum β-Lactamase Productivity, and Class 1 Integrons in Escherichia coli from Healthy Swine.

    Science.gov (United States)

    Changkaew, Kanjana; Intarapuk, Apiradee; Utrarachkij, Fuangfa; Nakajima, Chie; Suthienkul, Orasa; Suzuki, Yasuhiko

    2015-08-01

    Administration of antimicrobials to food-producing animals increases the risk of higher antimicrobial resistance in the normal intestinal flora of these animals. The present cross-sectional study was conducted to investigate antimicrobial susceptibility and extended-spectrum β-lactamase (ESBL)-producing strains and to characterize class 1 integrons in Escherichia coli in healthy swine in Thailand. All 122 of the tested isolates had drug-resistant phenotypes. High resistance was found to ampicillin (98.4% of isolates), chloramphenicol (95.9%), gentamicin (78.7%), streptomycin (77.9%), tetracycline (74.6%), and cefotaxime (72.1%). Fifty-four (44.3%) of the E. coli isolates were confirmed as ESBL-producing strains. Among them, blaCTX-M (45 isolates) and blaTEM (41 isolates) were detected. Of the blaCTX-M-positive E. coli isolates, 37 carried the blaCTX-M-1 cluster, 12 carried the blaCTX-M-9 cluster, and 5 carried both clusters. Sequence analysis revealed blaTEM-1, blaTEM-135, and blaTEM-175 in 38, 2, and 1 isolate, respectively. Eighty-seven (71%) of the 122isolates carried class 1 integrons, and eight distinct drug-resistance gene cassettes with seven different integron profiles were identified in 43 of these isolates. Gene cassettes were associated with resistance to aminoglycosides (aadA1, aadA2, aadA22, or aadA23), trimethoprim (dfrA5, dfrA12, or dfrA17), and lincosamide (linF). Genes encoding β-lactamases were not found in class 1 integrons. This study is the first to report ESBL-producing E. coli with a class 1 integron carrying the linF gene cassette in swine in Thailand. Our findings confirm that swine can be a reservoir of ESBL-producing E. coli harboring class 1 integrons, which may become a potential health risk if these integrons are transmitted to humans. Intensive analyses of animal, human, and environmental isolates are needed to control the spread of ESBL-producing E. coli strains. PMID:26219356

  17. Antimicrobial Drug–Resistant Escherichia coli in Wild Birds and Free-range Poultry, Bangladesh

    OpenAIRE

    Hasan, Badrul; Sandegren, Linus; Melhus, Åsa; Drobni, Mirva; Hernandez, Jorge; Waldenström, Jonas; Alam, Munirul; Olsen, Björn

    2012-01-01

    Multidrug resistance was found in 22.7% of Escherichia coli isolates from bird samples in Bangladesh; 30% produced extended-spectrum β-lactamases, including clones of CTX-M genes among wild and domestic birds. Unrestricted use of antimicrobial drugs in feed for domestic birds and the spread of resistance genes to the large bird reservoir in Bangladesh are growing problems.

  18. Colonization with Extraintestinal Pathogenic Escherichia coli among Nursing Home Residents and Its Relationship to Fluoroquinolone Resistance

    OpenAIRE

    Maslow, Joel N.; Lautenbach, Ebbing; Glaze, Thomas; Bilker, Warren; Johnson, James R.

    2004-01-01

    In a cross-sectional fecal prevalence survey involving 49 residents of a Veterans Affairs nursing home, 59% of subjects were colonized with extraintestinal pathogenic Escherichia coli (ExPEC), 22% were colonized with adhesin-positive E. coli, and 51% were colonized with fluoroquinolone-resistant E. coli. Among 80 unique isolates, adhesins correlated negatively and aerobactin correlated positively with fluoroquinolone resistance.

  19. Prevalence and antimicrobial resistance in Escherichia coli from food animals in Lagos, Nigeria

    Science.gov (United States)

    Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing animals fr...

  20. Prevalence of Antibiotic Resistance in Escherichia coli Isolated from Poultry Meat Supply in Isfahan

    OpenAIRE

    Farhad Safarpordehkordi; Emad Yahaghi; Ebrahim Khodaverdi Darian

    2014-01-01

    Background and Aim: Unfortunately, conventional antibiotic therapies which were used for cases of food poisoning caused by Escherichia coli are costly and ineffective. This study was carried out in order to detection and investigates the antibiotic resistance pattern of Escherichia coli isolated from chicken meat distributed in Isfahan province. Materials and Methods: 220 chicken meat samples were collected from shopping centers in Isfahan province. Samples were initially cultured and geno...

  1. Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh

    OpenAIRE

    Rahman, Shahedur; Parvez, Anowar Khasru; Islam, Rezuanul; Khan, Mahboob Hossain

    2011-01-01

    Background Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Methods Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli isolated f...

  2. Resistência a antimicrobianos de Escherichia coli isolada de dejetos suínos em esterqueiras Antibiotic-resistance of Escherichia coli isolates from stored pig slurry

    Directory of Open Access Journals (Sweden)

    F.F.P. Silva

    2008-06-01

    Full Text Available The antimicrobial resistance of 96 Escherichia coli strains isolated from a stabilization pond system on a pig-breeding farm was evaluated. Strains were tested for their resistance against 14 antimicrobial using the agar diffusion method. E. coli strains showed resistance to tetracycline (82.3%, nalidixic acid (64%, ampicilin (41%, sulfamethoxazole/trimethoprin (36%, sulfonamide (34%, cloranphenicol (274%, ciprofloxacin (19%, cefaclor (16%, streptomicyn (7.3%, neomicyn (1%, amoxacilin/ clavulanic acid (1%, and amikacin (1%. No resistance was observed to gentamicin and tobramycin, and 37.5% of E. coli strains were resistant to four or more antimicrobials. The multiresistance pattern was found in strains isolated during all sampled period. Strains showed a high variability in the antimicrobial resistance pattern.

  3. Development of quinoxaline 1, 4-dioxides resistance in Escherichia coli and molecular change under resistance selection.

    Directory of Open Access Journals (Sweden)

    Wentao Guo

    Full Text Available Quinoxaline 1, 4-dioxides (QdNOs has been used in animals as antimicrobial agents and growth promoters for decades. However, the resistance to QdNOs in pathogenic bacteria raises worldwide concern but it is barely known. To explore the molecular mechanism involved in development of QdNOs resistance in Escherichia coli, 6 strains selected by QdNOs in vitro and 21 strains isolated from QdNOs-used swine farm were subjected to MIC determination and PCR amplification of oqxA gene. A conjugative transfer was carried out to evaluate the transfer risk of QdNOs resistant determinant. Furthermore, the transcriptional profile of a QdNOs-resistant E. coli (79O4-2 selected in vitro with its parent strain 79-161 was assayed with a prokaryotic suppression subtractive hybridization (SSH PCR cDNA subtraction. The result showed that more than 95% (20/21 clinical isolates were oqxA positive, while all the 6 induced QdNOs-resistant strains carried no oqxA gene and exhibited low frequency of conjugation. 44 fragments were identified by SSH PCR subtraction in the QdNOs-resistant strain 79O4-2. 18 cDNAs were involved in biosynthesis of Fe-S cluster (narH, protein (rpoA, trmD, truA, glyS, ileS, rplFCX, rpsH, fusA, lipoate (lipA, lipid A (lpxC, trehalose (otsA, CTP(pyrG and others molecular. The 11 cDNAs were related to metabolism or degradation of glycolysis (gpmA and pgi and proteins (clpX, clpA, pepN and fkpB. The atpADG and ubiB genes were associated with ATP biosynthesis and electron transport chain. The pathway of the functional genes revealed that E. coli may adapt the stress generated by QdNOs or develop specific QdNOs-resistance by activation of antioxidative agents biosynthesis (lipoate and trehalose, protein biosynthesis, glycolysis and oxidative phosphorylation. This study initially reveals the possible molecular mechanism involved in the development of QdNOs-resistance in E. coli, providing with novel insights in prediction and assessment of the emergency

  4. Urinary Tract Physiological Conditions Promote Ciprofloxacin Resistance in Low-Level-Quinolone-Resistant Escherichia coli.

    Science.gov (United States)

    Martín-Gutiérrez, Guillermo; Rodríguez-Beltrán, Jerónimo; Rodríguez-Martínez, José Manuel; Costas, Coloma; Aznar, Javier; Pascual, Álvaro; Blázquez, Jesús

    2016-07-01

    Escherichia coli isolates carrying chromosomally encoded low-level-quinolone-resistant (LLQR) determinants are frequently found in urinary tract infections (UTIs). LLQR mutations are considered the first step in the evolutionary pathway producing high-level fluoroquinolone resistance. Therefore, their evolution and dissemination might influence the outcome of fluoroquinolone treatments of UTI. Previous studies support the notion that low urine pH decreases susceptibility to ciprofloxacin (CIP) in E. coli However, the effect of the urinary tract physiological parameters on the activity of ciprofloxacin against LLQR E. coli strains has received little attention. We have studied the activity of ciprofloxacin under physiological urinary tract conditions against a set of well-characterized isogenic E. coli derivatives carrying the most prevalent chromosomal mutations (ΔmarR, gyrA-S83L, gyrA-D87N, and parC-S80R and some combinations). The results presented here demonstrate that all the LLQR strains studied became resistant to ciprofloxacin (according to CLSI guidelines) under physiological conditions whereas the control strain lacking LLQR mutations did not. Moreover, the survival of some LLQR E. coli variants increased up to 100-fold after challenge with a high concentration of ciprofloxacin under UTI conditions compared to the results seen with Mueller-Hinton broth. These selective conditions could explain the high prevalence of LLQR mutations in E. coli Furthermore, our data strongly suggest that recommended methods for MIC determination produce poor estimations of CIP activity against LLQR E. coli in UTIs. PMID:27139482

  5. Silver nanoparticle-embedded polymersome nanocarriers for the treatment of antibiotic-resistant infections

    Science.gov (United States)

    Geilich, Benjamin M.; van de Ven, Anne L.; Singleton, Gloria L.; Sepúlveda, Liuda J.; Sridhar, Srinivas; Webster, Thomas J.

    2015-02-01

    The rapidly diminishing number of effective antibiotics that can be used to treat infectious diseases and associated complications in a physician's arsenal is having a drastic impact on human health today. This study explored the development and optimization of a polymersome nanocarrier formed from a biodegradable diblock copolymer to overcome bacterial antibiotic resistance. Here, polymersomes were synthesized containing silver nanoparticles embedded in the hydrophobic compartment, and ampicillin in the hydrophilic compartment. Results showed for the first time that these silver nanoparticle-embedded polymersomes (AgPs) inhibited the growth of Escherichia coli transformed with a gene for ampicillin resistance (bla) in a dose-dependent fashion. Free ampicillin, AgPs without ampicillin, and ampicillin polymersomes without silver nanoparticles had no effect on bacterial growth. The relationship between the silver nanoparticles and ampicillin was determined to be synergistic and produced complete growth inhibition at a silver-to-ampicillin ratio of 1 : 0.64. In this manner, this study introduces a novel nanomaterial that can effectively treat problematic, antibiotic-resistant infections in an improved capacity which should be further examined for a wide range of medical applications.

  6. No Development of Imipenem Resistance in Pneumonia Caused by Escherichia coli

    OpenAIRE

    Yayan, Josef; Ghebremedhin, Beniam; Rasche, Kurt

    2015-01-01

    Background: Antibiotic resistance continues to rise due to the increased number of antibiotic prescriptions and is now a major threat to public health. In particular, there is an increase in antibiotic resistance to Escherichia coli according to the latest reports. Trial Design: This article examines, retrospectively, antibiotic resistance in patients with community- and nosocomial-acquired pneumonia caused by E coli. Methods: The data of all patients with community- and nosocomial-acquired p...

  7. Characterization of a novel tetracycline resistance that functions only in aerobically grown Escherichia coli.

    OpenAIRE

    Speer, B S; Salyers, A A

    1988-01-01

    A tetracycline resistance (Tcr) gene that was found originally on two Bacteroides plasmids (pBF4 and pCP1) confers tetracycline resistance on Escherichia coli, but only when it is grown aerobically. Using maxicells, we have identified a 44-kilodalton protein which is encoded by the region that carries the Tcr gene and which may be the Tcr gene product. Localization experiments indicate that this 44-kilodalton protein is cytoplasmic. To determine whether the tetracycline resistance gene is exp...

  8. Antimicrobial-Resistant Escherichia coli in Public Beach Waters in Quebec

    Directory of Open Access Journals (Sweden)

    Patricia Turgeon

    2012-01-01

    Full Text Available INTRODUCTION: Human exposure to antimicrobial-resistant bacteria may result in the transfer of resistance to commensal or pathogenic microbes present in the gastrointestinal tract, which may lead to severe health consequences and difficulties in treatment of future bacterial infections. It was hypothesized that the recreational waters from beaches represent a source of antimicrobial-resistant Escherichia coli for people engaging in water activities.

  9. Epidemiological and clinical complexity of amoxicillin-clavulanate-resistant Escherichia coli.

    Science.gov (United States)

    Rodríguez-Baño, Jesús; Oteo, Jesús; Ortega, Adriana; Villar, Macarena; Conejo, M Carmen; Bou, Germán; Aranzamendi-Zaldumbide, Maitane; Cercenado, Emilia; Gurguí, Mercè; Martínez-Martínez, Luis; Merino, María; Rivera, Alba; Oliver, Antonio; Weber, Irene; Pascual, Alvaro; Bartolomé, Rosa M; Gónzalez-López, Juan José; Campos, José

    2013-07-01

    Two hundred twelve patients with colonization/infection due to amoxicillin-clavulanate (AMC)-resistant Escherichia coli were studied. OXA-1- and inhibitor-resistant TEM (IRT)-producing strains were associated with urinary tract infections, while OXA-1 producers and chromosomal AmpC hyperproducers were associated with bacteremic infections. AMC resistance in E. coli is a complex phenomenon with heterogeneous clinical implications. PMID:23637303

  10. Virulence factors associated with antimicrobial resistance determinants among Escherichia coli and Klebsiella spp

    OpenAIRE

    Calhau, Vera Mónica Tavares Vinhas

    2014-01-01

    Escherichia coli and Klebsiella spp. are important pathogens, responsible for several infectious diseases. These members of Enterobacteriaceae family are of particularly concerning due to a high increase in their resistance to antimicrobials. The detection of more resistant strains brings into question if this enhancement of resistance may be accompanied by an increase in virulence. If so, extremely pathogenic strains would start to emerge, and no antibiotic therapy would be available to figh...

  11. Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England

    OpenAIRE

    Williams Nicola J; Clegg Peter D; Ahmed Mohamed O; Baptiste Keith E; Bennett Malcolm

    2010-01-01

    Abstract Background Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhib...

  12. Lytic phages obscure the cost of antibiotic resistance in Escherichia coli

    OpenAIRE

    Tazzyman, Samuel J; Hall, Alex R

    2014-01-01

    The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under pha...

  13. Antimicrobial resistance, genotypic characterization and pulsed-field gel electrophoresis typing of extended spectrum β-lactamases-producing clinical Escherichia coli strains in Macao, China

    Institute of Scientific and Technical Information of China (English)

    YE Qian-hong; LAU Ying; LIANG Bin; TIAN Su-fei

    2011-01-01

    Background The rise of the production of CTX-M class extended spectrum β-lactamases (ESBLs) has been well documented in traveling countries but no data are found for Macao,an international travel city.The objectives of this study were to identify the antimicrobial resistance pattern,and determine the prevalence,genotype and clonal relationship of ESBLs in 209 clinical Escherichia coli strains from Macao,China.Methods Antimicrobial susceptibility test was performed to determine the resistance patterns of the isolates using the disk diffusion method with 17 antimicrobial agents.Phenotypic detection was screened and confirmed according to the Clinical and Laboratory Standards Institute.Genotypic characterization was detected by isoelectric focusing analysis,polymerase chain reaction and sequencing.The clonal relationship between the different ESBL isolates was studied by pulsed-field gel electrophoresis (PFGE).Results Imipenem and meropenem exhibited 100% susceptible among 209 strains.Overall,82.3%,67.3%,52.9%,51.2% and 51.0% of the isolates displayed resistance to ampicillin,tetracylcline,ciprofloxacin,sulfamethoxazole trimethoprin and gentamycin.The prevalence rate of ESBLs was 30.1%.Antibiotic resistances were found to be significantly higher among the ESBL producing group compared to non-ESBL producing group.We detected CTX-M-14 to be the major genotypic characterization of ESBLs (76.2%).Two strains showed indistinguishable patterns by PFGE.Conclusions The prevalence of antimicrobial resistance is alarming high in Macao.Antimicrobial resistance is significantly higher among the ESBL producing group.This study documented CTX-M-14 as the predominant ESBL type.Although indistinguishable pattern was found between two strains,it was too small to decide whether any of the investigated strains was epidemic.Our findings may be also pertinent for other geographic areas undergoing similar travel characteristics to understand the corresponding effects on bacterial

  14. Cryptic tetracycline resistance determinant (class F) from Bacteroides fragilis mediates resistance in Escherichia coli by actively reducing tetracycline accumulation.

    OpenAIRE

    Park, B. H.; Hendricks, M; Malamy, M H; Tally, F P; Levy, S. B.

    1987-01-01

    Escherichia coli bearing a cryptic tetracycline resistance determinant from Bacteroides fragilis expressed low-level constitutive resistance to tetracycline under aerobic, but not anaerobic, growth conditions and accumulated less tetracycline aerobically than did isogenic susceptible cells. This decreased uptake was energy dependent and reversible by increased concentrations of tetracycline, suggesting a saturable carrier-mediated active efflux mechanism. Decreased uptake was not seen when th...

  15. Study of the resistance mechanisms to ultraviolet radiation in Escherichia Coli. II. General characteristics of the mutants resistant to ultraviolet radiation of Escherichia Coli PQ30

    International Nuclear Information System (INIS)

    Inside this second work the results are shown on the preliminary characterization of the 5 populations of Escherichia coli that its were subjected to the light UV, by means of 80 irradiation- growth cycles, the dose of which it was duplicated each 10 cycles. The course that the resistance to UV to those 5 populations continued along the process, that covers some 165 generations, and the level reached at the end by each one of them suggests the presence of different resistance mechanisms to the UV light. (Author)

  16. Plasmid profiling of multidrug resistant Escherichia coli strains isolated from urinary tract infection patients

    Directory of Open Access Journals (Sweden)

    Sabin Khadgi

    2013-03-01

    Full Text Available Introduction- Urinary tract infection is a common community-acquired bacterial disease. Escherichia coli is reported to be the major cause of urinary tract infection. Aim & Objective- The study was conducted with the aim of determining the antibiotic resistance pattern and plasmid profile of multidrug resistant Escherichia coli isolated from Urinary Tract Infection patients. Materials and Method- Antibiotic susceptibility tests were performed against E. coli following the protocol for the Kirby-Bauer disc diffusion method. Plasmid DNA was isolated following the protocol of Kado and Liu. Results- Multidrug resistant isolates exhibited high resistance to drugs like Amoxicillin, Cefixime, Ciprofloxacin, Cotrimethoxazole, Norfloxacin and Ofloxacin. The plasmid profiling showed that all, except one, isolate contained at least one plasmid. A band of approximately 23 kb was seen in most of the isolates.

  17. Mechanisms of antibiotic resistance to enrofloxacin in uropathogenic Escherichia coli in dog

    Science.gov (United States)

    Escherichia coli (E. coli) urinary tract infections (UTIs) are becoming a serious problem both for pets and humans (zoonosis) due to the close contact and to the increasing resistance to antibiotics. Canine E. coli represents a good experimental model useful to study this pathology. Moreover, as des...

  18. Seagulls and Beaches as Reservoirs for Multidrug-ResistantEscherichia coli

    OpenAIRE

    Simões, Roméo Rocha; Poirel , Laurent; da Costa, Paulo Martins; Nordmann, Patrice

    2009-01-01

    A variety of extended-spectrum β-lactamase–producing Escherichia coli isolates, with a high rate of cefotaximase-15 resistance, were identified in seagull feces from Porto, Portugal, beaches. Beaches may therefore present a risk to public health because of the potential pathogen-spreading capacity of migratory birds.

  19. OCCURRENCE OF ANTIBIOTIC-RESISTANT UROPATHOGENIC ESCHERICHIA COLI CLONAL GROUP A IN WASTEWATER EFFLUENTS

    Science.gov (United States)

    Isolates of Escherichia coli belonging to clonal group A (CGA), a recently described disseminated cause of drug-resistant urinary tract infections in humans, were present in four of seven sewage effluents collected from geographically dispersed areas of the United States. ...

  20. Colistin Resistance mcr-1-Gene-Bearing Escherichia coli Strain from the United States

    Science.gov (United States)

    Ladely, Scott R.; Plumblee, Jodie R.; Hall, M. Carolina; Simpson, Sheron A.; Ballard, Linda L.; Scheffler, Brian E.; Genzlinger, Linda L.; Cook, Kimberly L.

    2016-01-01

    Transmissible colistin resistance in the form of an mcr-1-gene-bearing plasmid has been recently reported in Enterobacteriaceae in several parts of the world. We report here the completed genome sequence of an Escherichia coli strain isolated from swine in the United States that carried the mcr-1 gene on an IncI2-type plasmid. PMID:27587816

  1. Valine-Resistant Escherichia coli K-12 Strains with Mutations in the ilvB Operon

    OpenAIRE

    Sutton, Ann; Newman, Thomas; Francis, Marilyn; Freundlich, Martin

    1981-01-01

    Escherichia coli K-12 mutants resistant to growth inhibition by valine were isolated. These strains contained mutations in the ilvB operon effecting either the regulation of acetohydroxy acid synthase I or the sensitivity of the enzyme to end product inhibition by valine.

  2. Detection, Virulence Gene Assessment and Antibiotic Resistance Pattern of O157 Enterohemorrhagic Escherichia coli in Tabriz, Iran

    Science.gov (United States)

    Akhi, Mohammad Taghi; Ostadgavahi, Ali Toloue; Ghotaslou, Reza; Asgharzadeh, Mohammad; Pirzadeh, Tahereh; Sorayaei Sowmesarayi, Vida; Memar, Mohammad Yousef

    2015-01-01

    Background: Shiga toxin-producing Escherichia coli (STEC) is a food-borne pathogen and infection with this organism causes illnesses such as bloody diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome. Objectives: Considering the lack of any information about the prevalence rate and the antibiotic resistance pattern of O157:H7 serotype in Tabriz, finding answers to the above mentioned subjects was among the goals of this study. Materials and Methods: Two hundred E. coli strains from diarrheal or non-diarrheal stools of outpatients and hospitalized cases in Tabriz Imam Reza hospital were isolated between September and December 2014 using MacConkey agar and standard biochemical tests and then cultured on sorbitol MacConkey agar. The sorbitol-negative isolates were confirmed as the O157 serotype using O157 antisera. A multiplex polymerase chain reaction (PCR) method was used for the detection of stx-1, stx-2, eae, and mdh genes and the antibiotic resistance pattern of these isolates was determined using Kirby-Bauer method and clinical and laboratory standards institute (CLSI) standards. Results: Of the isolates 11 (5.5%) were sorbitol-negative, which were later analyzed by multiplex PCR and the results revealed that 2 (18.18%) isolates contained the stx-1 gene, 10 (90.91%) contained the stx-2 gene, and 5 (45.45%) contained the eae gene. The stx-2 and eae genes were the most commonly encountered virulence factors. All or most of the isolates were susceptible to ceftazidime (100%), gentamicin (100%), ciprofloxacin (100%), nalidixic acid (90.9%), trimetoprim sulfamethoxazole (90.9%), chloramphenicol (90.9%), ampicillin (81.8%), and cephalothin (72.7%). On the contrary, moderate susceptibility of the isolates to doxycycline (54.5%) was observed. Conclusions: Due to the low frequency of STEC O157 and the high susceptibility rates of the isolates to the tested antibiotics in this study, STEC O157 has not become a major problem in Tabriz yet, but comprehensive

  3. Inhibition of the multiple antibiotic resistance (mar) operon in Escherichia coli by antisense DNA analogs.

    OpenAIRE

    White, D G; Maneewannakul, K; von Hofe, E; Zillman, M; Eisenberg, W; Field, A K; Levy, S. B.

    1997-01-01

    The multiple antibiotic resistance operon (marORAB) in Escherichia coli controls intrinsic susceptibility and resistance to multiple, structurally different antibiotics and other noxious agents. A plasmid construct with marA cloned in the antisense direction reduced LacZ expression from a constitutively expressed marA::lacZ translational fusion and inhibited the induced expression of LacZ in cells bearing the wild-type repressed fusion. The marA antisense construction also decreased the multi...

  4. Virulence factors and drug resistance in Escherichia coli isolated from extraintestinal infections

    OpenAIRE

    Sharma S; Bhat G; Shenoy S

    2007-01-01

    Purpose: To determine the virulence factors produced by Escherichia coli isolated from extraintestinal infections, to study the drug resistance pattern in E. coli with special reference to extended spectrum β -lactamase (ESBL) and to evaluate screening methods for ESBL. Methods: A total of 152 isolates of E. coli from various extraintestinal infections were screened for virulence factors such as haemolysin, surface hydrophobicity, serum resistance and protease. All the isolates ...

  5. Role of outer membrane barrier in efflux-mediated tetracycline resistance of Escherichia coli.

    OpenAIRE

    Thanassi, D. G.; Suh, G S; Nikaido, H

    1995-01-01

    Accumulation of tetracycline in Escherichia coli was studied to determine its permeation pathway and to provide a basis for understanding efflux-mediated resistance. Passage of tetracycline across the outer membrane appeared to occur preferentially via the porin OmpF, with tetracycline in its magnesium-bound form. Rapid efflux of magnesium-chelated tetracycline from the periplasm was observed. In E. coli cells that do not contain exogenous tetracycline resistance genes, the steady-state level...

  6. The Association of Virulence Determinants of Uropathogenic Escherichia coli With Antibiotic Resistance

    OpenAIRE

    Sara Asadi; Mohammad Kargar; Kavous Solhjoo; Akram Najafi; Sadegh Ghorbani-Dalini

    2014-01-01

    Background: The emergence of antimicrobial resistant strains of Escherichia coli has raised considerable interest in understanding the diversity and epidemiology of E. coli infections in humans. Virulence factors of E. coli determine the specific infections caused by this microorganism. Objectives: This study aimed to determine the prevalence of eight E. coli virulence factors and their association with antimicrobial resistance in bacteria isolated from patients with urinary tract infecti...

  7. Comparison of antibiotic resistance patterns in collections of Escherichia coli and Proteus mirabilis uropathogenic strains

    OpenAIRE

    Adamus-Bialek, Wioletta; Zajac, Elzbieta; Parniewski, Pawel; Kaca, Wieslaw

    2013-01-01

    Escherichia coli and Proteus mirabilis are important urinary tract pathogens. The constant increase in the antibiotic resistance of clinical bacterial strains has become an important clinical problem. The aim of this study was to compare the antibiotic resistance of 141 clinical (Sweden and Poland) and 42 laboratory (Czech Republic) P. mirabilis strains and 129 clinical (Poland) uropathogenic E. coli strains. The proportion of unique versus diverse patterns in Swedish clinical and laboratory ...

  8. A Corynebacterium glutamicum gene conferring multidrug resistance in the heterologous host Escherichia coli.

    OpenAIRE

    Jäger, W; Kalinowski, J.; Pühler, A

    1997-01-01

    A chromosomal DNA fragment from the erythromycin-sensitive bacterium Corynebacterium glutamicum ATCC 13032 was shown to mediate resistance against erythromycin, tetracycline, puromycin, and bleomycin in Escherichia coli. Multicopy cloning of the fragment did not cause a resistance phenotype in C. glutamicum. The corresponding gene encodes a hydrophobic protein with 12 potential transmembrane-spanning ex-helical segments showing similarity to drug-H+ antiporters.

  9. Colonization with Extraintestinal Pathogenic Escherichia coli among Nursing Home Residents and Its Relationship to Fluoroquinolone Resistance

    Science.gov (United States)

    Maslow, Joel N.; Lautenbach, Ebbing; Glaze, Thomas; Bilker, Warren; Johnson, James R.

    2004-01-01

    In a cross-sectional fecal prevalence survey involving 49 residents of a Veterans Affairs nursing home, 59% of subjects were colonized with extraintestinal pathogenic Escherichia coli (ExPEC), 22% were colonized with adhesin-positive E. coli, and 51% were colonized with fluoroquinolone-resistant E. coli. Among 80 unique isolates, adhesins correlated negatively and aerobactin correlated positively with fluoroquinolone resistance. PMID:15328142

  10. Wastewater as a Source of Carbapenem Resistant Escherichia coli

    Science.gov (United States)

    Clinical studies have reported that the occurrence of carbapenem resistant E. coli is on the rise. This is of concern because carbapenem antibiotics are typically reserved for treating infections caused by bacteria resistant to other classes of antibiotics. Current literature st...

  11. High levels of antimicrobial resistance among escherichia coli isolates from livestock farms and synanthropic rats and shrews in the Mekong Delta of Vietnam.

    Science.gov (United States)

    Nhung, N T; Cuong, N V; Campbell, J; Hoa, N T; Bryant, J E; Truc, V N T; Kiet, B T; Jombart, T; Trung, N V; Hien, V B; Thwaites, G; Baker, S; Carrique-Mas, J

    2015-02-01

    In Mekong Delta farms (Vietnam), antimicrobials are extensively used, but limited data are available on levels of antimicrobial resistance (AMR) among Escherichia coli isolates. We performed a structured survey of AMR in E. coli isolates (n = 434) from 90 pig, chicken, and duck farms. The results were compared with AMR among E. coli isolates (n = 234) from 66 small wild animals (rats and shrews) trapped on farms and in forests and rice fields. The isolates were susceptibility tested against eight antimicrobials. E. coli isolates from farmed animals were resistant to a median of 4 (interquartile range [IQR], 3 to 6) antimicrobials versus 1 (IQR, 1 to 2) among wild mammal isolates (P tetracycline, 84.7% (versus 25.6%); ampicillin, 78.9% (versus 85.9%); trimethoprim-sulfamethoxazole, 52.1% (versus 18.8%); chloramphenicol, 39.9% (versus 22.5%); amoxicillin-clavulanic acid, 36.6% (versus 34.5%); and ciprofloxacin, 24.9% (versus 7.3%). The prevalence of multidrug resistance (MDR) (resistance against three or more antimicrobial classes) among pig isolates was 86.7% compared to 66.9 to 72.7% among poultry isolates. After adjusting for host species, MDR was ∼8 times greater among isolates from wild mammals trapped on farms than among those trapped in forests/rice fields (P < 0.001). Isolates were assigned to unique profiles representing their combinations of susceptibility results. Multivariable analysis of variance indicated that AMR profiles from wild mammals trapped on farms and those from domestic animals were more alike (R(2) range, 0.14 to 0.30) than E. coli isolates from domestic animals and mammals trapped in the wild (R(2) range, 0.25 to 0.45). The results strongly suggest that AMR on farms is a key driver of environmental AMR in the Mekong Delta. PMID:25398864

  12. Shiga Toxin-Producing Escherichia coli Isolated from Bovine Mastitic Milk: Serogroups, Virulence Factors, and Antibiotic Resistance Properties

    OpenAIRE

    Hassan Momtaz; Farhad Safarpoor Dehkordi; Taghi Taktaz; Amir Rezvani; Sajad Yarali

    2012-01-01

    The aim of this study was to detect the virulence factors, serogroups, and antibiotic resistance properties of Shiga toxin-producing Escherichia coli, by using 268 bovine mastitic milk samples which were diagnosed using California Mastitis Test. After E. coli identification, PCR assays were developed for detection of different virulence genes, serogroups, and antibiotic resistance genes of Escherichia coli. The antibiotic resistance pattern was studied using disk diffusion method. Out of 268 ...

  13. Antibiotic Selection of Escherichia coli Sequence Type 131 in a Mouse Intestinal Colonization Model

    OpenAIRE

    Boetius Hertz, Frederik; Løbner-Olesen, Anders; Frimodt-Møller, Niels

    2014-01-01

    The ability of different antibiotics to select for extended-spectrum β-lactamase (ESBL)-producing Escherichia coli remains a topic of discussion. In a mouse intestinal colonization model, we evaluated the selective abilities of nine common antimicrobials (cefotaxime, cefuroxime, dicloxacillin, clindamycin, penicillin, ampicillin, meropenem, ciprofloxacin, and amdinocillin) against a CTX-M-15-producing E. coli sequence type 131 (ST131) isolate with a fluoroquinolone resistance phenotype. Mice ...

  14. Antimicrobial resistance in commensal Escherichia coli in veal calves is associated with antimicrobial drug use.

    Science.gov (United States)

    Bosman, A B; Wagenaar, J A; Stegeman, J A; Vernooij, J C M; Mevius, D J

    2014-09-01

    The aim of this study was to determine the association between farm management factors, including antimicrobial drug usage, and resistance in commensal Escherichia coli isolates from the faeces of white veal calves. Ninety E. coli isolates from one pooled sample per farm (n = 48) were tested for their phenotypical resistance against amoxicillin, tetracycline, cefotaxime, ciprofloxacin and trimethoprim/sulfamethoxazole (TMP/SMX). Logistic regression analysis revealed the following risk factors (P 40 ADD/pc, tetracyclines (tetracycline, OR 13·1; amoxicillin, OR 6·5). In this study antimicrobial resistance in commensal E. coli was mainly associated with antimicrobial drug use. PMID:24152540

  15. Fluoroquinolone-resistant Escherichia coli Carriage in Long-Term Care Facility

    OpenAIRE

    Maslow, Joel N.; Lee, Betsy; Lautenbach, Ebbing

    2005-01-01

    We conducted a cross-sectional study to determine the prevalence of, and risk factors for, colonization with fluoroquinolone (FQ)-resistant Escherichia coli in residents in a long-term care facility. FQ-resistant E. coli were identified from rectal swabs for 25 (51%) of 49 participants at study entry. On multivariable analyses, prior FQ use was the only independent risk factor for FQ-resistant E. coli carriage and was consistent for FQ exposures in the previous 3, 6, 9, or 12 months. Pulsed-f...

  16. Quinolone resistance and ornithine decarboxylation activity in lactose-negative Escherichia coli

    Directory of Open Access Journals (Sweden)

    Franciane Gomig

    2015-09-01

    Full Text Available Quinolones and fluoroquinolones are widely used to treat uropathogenic Escherichia coli infections. Bacterial resistance to these antimicrobials primarily involves mutations in gyrA and parC genes. To date, no studies have examined the potential relationship between biochemical characteristics and quinolone resistance in uropathogenic E. coli strains. The present work analyzed the quinolone sensitivity and biochemical activities of fifty-eight lactose-negative uropathogenic E. coli strains. A high percentage of the isolates (48.3% was found to be resistant to at least one of the tested quinolones, and DNA sequencing revealed quinolone resistant determining region gyrA and parC mutations in the multi-resistant isolates. Statistical analyses suggested that the lack of ornithine decarboxylase (ODC activity is correlated with quinolone resistance. Despite the low number of isolates examined, this is the first study correlating these characteristics in lactose-negative E. coli isolates.

  17. Effects of halides on plasmid-mediated silver resistance in Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, A.; Maynes, M.; Silver, S. [Univ. of Illinois, Chicago, IL (United States). Dept. of Microbiology and Immunology

    1998-12-01

    Silver resistance of sensitive Escherichia coli J53 and resistance plasmid-containing J53(pMG101) was affected by halides in the growth medium. The effects of halides on Ag{sup +} resistance were measured with AgNO{sub 3} and silver sulfadiazine, both on agar and in liquid. Low concentrations of chloride made the differences in MICs between sensitive and resistant strains larger. High concentrations of halides increased the sensitivities of both strains to Ag{sup +}. The purpose of this report is to set out easy-to-use conditions for measuring silver sensitivity and resistance in familiar and widely used media, Luria-Bertani (LB) agar and broth, so as to facilitate wider identification of silver resistance in nature.

  18. Prevalence and Antibiotic Resistance Profiles of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Healthy Broilers in Shandong Province, China.

    Science.gov (United States)

    Li, Song; Zhao, Miaomiao; Liu, Junhe; Zhou, Yufa; Miao, Zengmin

    2016-07-01

    Food-producing animals carrying extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) have posed a potential threat to human and animal health. However, information regarding ESBL-EC in the intensive broiler breeding areas of Shandong Province, People's Republic of China, is very limited. The goal of our study was to investigate the prevalence and drug resistance characteristics of ESBL-EC in healthy broilers from Shandong Province. A total of 142 ESBL-EC isolates were collected from four prefectures in Shandong Province from October 2014 to February 2015. ESBL-EC isolates were frequently detected (142 of 160 samples, 88.8%) in healthy broilers. Antibiotic susceptibility testing showed that all 142 ESBL-EC isolates were resistant to ampicillin, piperacillin, and cefazolin but were sensitive to imipenem and meropenem. All ESBL-EC isolates carried one or more of the bla genes, in which blaCTX-M, blaTEM-1, and blaSHV-5 genes were identified in 142, 106, and 5 isolates, respectively. The blaCTX-M gene includes blaCTX-M-15 (56), blaCTX-M-65 (42), blaCTX-M-55 (36), blaCTX-M-14 (21), blaCTX-M-79 (1), blaCTX-M-3 (1), blaCTX-M-123 (1), and blaCTX-M-132 (1). In addition, 17 ESBL-EC isolates cocarried the genes of the CTX-M-1 and CTX-M-9 groups. Our findings indicate that healthy broiler flocks in Shandong Province in China are an important reservoir for ESBL-EC, with blaCTX-M and blaTEM-1 being the prevalent resistance genes identified. PMID:27357036

  19. Vegetables and Restaurant Salads as a Reservoir for Shiga Toxigenic Escherichia coli: Distribution of Virulence Factors, O-Serogroups, and Antibiotic Resistance Properties.

    Science.gov (United States)

    Shakerian, Amir; Rahimi, Ebrahim; Emad, Pardis

    2016-07-01

    Close contact of vegetables with soil, polluted water, and animal manure and unsanitary conditions during processing of restaurant salads led us to study the distribution of virulence factors, O-serogroups, and antibiotic resistance properties in Shiga toxigenic Escherichia coli (STEC) isolated from vegetables and salads. Samples of vegetables and salad (n = 420) were collected and evaluated for the presence of E. coli using culture and a PCR assay. Total prevalence of E. coli in studied samples was 49.5%. E. coli was found in 49.6% of vegetable samples and 49% of salad samples. Leek and traditional salad had the highest incidence of E. coli. Significant differences in the incidence of E. coli were found between the hot and cold seasons. Of the 149 E. coli isolates from vegetable samples, 130 (87%) were STEC, and of the 59 E. coli isolates from salad samples, 50 (84%) were STEC. The most commonly detected virulence factors were stx1 and eaeA. A significant difference was found between the frequency of the attaching and effacing and the enterohemorrhagic E. coli subtypes. Serogroups O26 (46% of isolates), O157 (14%), O121 (10%), and O128 (9%) were the most commonly detected serogroups among the STEC strains. The tetA, sul1, aac(3)-IV, dfrA1, blaSHV, and CITM antibiotic resistance genes were found in 96, 47.7, 90, 51, 27, and 93% of isolates, respectively. The highest levels of resistance were found against ampicillin (96.6% of isolates), tetracycline (87%), and gentamicin (90%). This study shows the importance of vegetables and salads as potential sources of E. coli infection. PMID:27357034

  20. Antimicrobial susceptibility of clinical isolates of Haemophilus influenzae to ampicillin-sulbactam.

    Science.gov (United States)

    Mortensen, J E; LaRocco, M; Himes, S L; Inderlied, C; Daly, J A; Campos, J M; Mendelman, P M

    1990-01-01

    A total of 1092 clinical isolates of Haemophilus influenzae (306 type b; 786 non-type-b), from five medical centers were obtained during 1987 and 1988. Disk diffusion antimicrobial susceptibilities were obtained for all isolates, and broth microdilution susceptibilities were obtained for 502 isolates. Beta-lactamase was produced by 34.3% of type-b and 22.1% of non-type-b isolates, with some geographic variations. Using disk diffusion antimicrobial susceptibility testing, all isolates were susceptible to ampicillin-sulbactam, ceftriaxone, cefuroxime, and rifampin; two isolates were resistant to chloramphenicol. Whether tested using a fixed ratio of ampicillin to sulbactam of 2:1 or a fixed concentration of sulbactam, the ampicillin-sulbactam combination demonstrated good activity against clinical isolates of H. influenzae. Only 8 of the 1092 isolates did not produce beta-lactamase but demonstrated MICs of greater than or equal to 2 micrograms/ml for ampicillin. PMID:2076596

  1. Antibiotic Resistance Patterns in Enteric and Uropathogenic Strains of Escherichia Coli in Children

    Directory of Open Access Journals (Sweden)

    This paper should be cited as: Sedighi I, Alikhani MY, Nakhaee S, Karami P . [ Antibiotic Resistance Patterns in Enteric and Uropathogenic Strains of Escherichia Coli in Children ]. mlj goums . 201 4 ; 8 ( Suppl 4 : 42 - 48 [Article in Per sian] Sedi ghi, I. (MD

    2014-11-01

    Full Text Available Background and Objective: Escherichia coli is the most common cause of urinary tract infections in children and the leading cause of intra-abdominal infections (peritonitis and abscess followed intestinal injuries. Urinary tract infection, including cystitis and pyelonephritis, is a common childhood infection. E. coli causes more than 90 percent of the community acquired and 50% of hospital acquired urinary tract infections; therefore, the determination of E. coli antibiotic susceptibility is a paramount importance to clinical and epidemiological purposes. Material and Methods: In this cross-sectional study, 50 E. coli strains isolated from urine samples of children less than 7 years of age with urinary tract infections. They were compared for drug susceptibility testing by disc diffusion method with 50 strains of Escherichia coli isolated from stool samples of healthy children with the same age and sex pattern. Results: The actual amount of drug sensitivity of uropathogenic and intestinal Escherichia coli strains to amikacin was 94 and 100%, nitrofurantoin 90 and 88%, gentamicin 66 and 94%, cefixime 56 and 60%, nalidixic acid 38 and 44% and to cotrimoxazole 28 and 32%, respectively. Conclusion: the rate of resistance to gentamicin, Cefixime and nalidixic acid in urinary tract infection isolates were more than intestinal strains. The highest rate of drug resistance in urinary Escherichia coli isolates was associated with cotrimoxazole and the lowest one with amikacin.

  2. Antibiotic resistance patterns in Escherichia coli from gulls in nine European countries

    Directory of Open Access Journals (Sweden)

    Johan Stedt

    2014-01-01

    Full Text Available Background: The prevalence of antibiotic resistant faecal indicator bacteria from humans and food production animals has increased over the last decades. In Europe, resistance levels in Escherichia coli from these sources show a south-to-north gradient, with more widespread resistance in the Mediterranean region compared to northern Europe. Recent studies show that resistance levels can be high also in wildlife, but it is unknown to what extent resistance levels in nature conform to the patterns observed in human-associated bacteria. Methods: To test this, we collected 3,158 faecal samples from breeding gulls (Larus sp. from nine European countries and tested 2,210 randomly isolated E. coli for resistance against 10 antibiotics commonly used in human and veterinary medicine. Results: Overall, 31.5% of the gull E. coli isolates were resistant to ≥1 antibiotic, but with considerable variation between countries: highest levels of isolates resistant to ≥1 antibiotic were observed in Spain (61.2% and lowest levels in Denmark (8.3%. For each tested antibiotic, the Iberian countries were either the countries with the highest levels or in the upper range in between-country comparisons, while northern countries generally had a lower proportion of resistant E. coli isolates, thereby resembling the gradient of resistance seen in human and food animal sources. Conclusion: We propose that gulls may serve as a sentinel of environmental levels of antibiotic resistant E. coli to complement studies of human-associated microbiota.

  3. Antibiotic resistance and plasmid carriage among Escherichia coli isolates from chicken meat in Malaysia

    International Nuclear Information System (INIS)

    Escherichia coli isolates from 131 raw chicken meat samples were tested for susceptibility to 12 antibiotics. Plasmids were isolated from many samples and their DNA molecular weight calculated. An 81.7% plasmid occurrence rate was observed among the isolates, ranging from 0 to 8 in number and with sizes from 1.2 to 118.6 MDa. Plasmids were detected in 93.8% of E. coIi isolates resistant to all 12 antibiotics, and in 90.5% of E. coli isolates resistant to 11. Three (2.8%) isolates harboured 8 plasmids and were resistant to all 12 antibiotics. Antibiotic resistant genes in bacteria are usually carried in extrachromosomal DNA and it is postulated that E. coli with a high number of plasmids possesses wider resistance to antibiotics. (author)

  4. Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran.

    Science.gov (United States)

    Talebiyan, Reza; Kheradmand, Mehdi; Khamesipour, Faham; Rabiee-Faradonbeh, Mohammad

    2014-01-01

    Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%), Erythromycin (71.70%), Oxytetracycline (43.40%), Sulfadimethoxine-Trimethoprim (39.62%), Enrofloxacin (37.74%), Florfenicol (35.85%), Chlortetracycline (33.96%), Doxycycline (16.98%), Difloxacin (32.08%), Danofloxacin (28.30%), Chloramphenicol (20.75%), Ciprofloxacin (7.55%), and Gentamicin (5.66%). This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances. PMID:25548716

  5. Determination Pattern of Antibiotic Resistance in Entropathogenic Escherichia coli Strains Isolated from Children with Diarrhea

    OpenAIRE

    P. Karami; Aslani, M M; M. Najafi Mosleh; M.Y. Alikhani

    2012-01-01

    Introduction & Objective: Diarrheal diseases are considered a major health problem, especially in children. Enteropathogenic Escherichia coli (EPEC) strains are the common cause of diarrhea in children especially in developing countries. Because of undesirable effects of diarrhea and its interference with children's growth, in some cases antibiotic treatment is recommended. In recent years, resistance toward common and effective antibiotics in the treatment of infectious diseases became one o...

  6. Genome of Multidrug-Resistant Uropathogenic Escherichia coli Strain NA114 from India ▿

    OpenAIRE

    Avasthi, Tiruvayipati Suma; Kumar, Narender; Baddam, Ramani; Hussain, Arif; Nandanwar, Nishant; Jadhav, Savita; Ahmed, Niyaz

    2011-01-01

    Uropathogenic Escherichia coli (UPEC) causes serious infections in people at risk and has a significant environmental prevalence due to contamination by human and animal excreta. In developing countries, UPEC assumes importance in certain dwellings because of poor community/personal hygiene and exposure to contaminated water or soil. We report the complete genome sequence of E. coli strain NA114 from India, a UPEC strain with a multidrug resistance phenotype and the capacity to produce extend...

  7. Chaperone Hsp31 contributes to acid resistance in stationary-phase Escherichia coli.

    Science.gov (United States)

    Mujacic, Mirna; Baneyx, François

    2007-02-01

    Hsp31, the product of the sigmaS - and sigmaD -dependent hchA gene, is a heat-inducible chaperone implicated in the management of protein misfolding at high temperatures. We show here that Hsp31 plays an important role in the acid resistance of starved Escherichia coli but that it has little influence on oxidative-stress survival. PMID:17158627

  8. Characterization of Multiple-Antimicrobial-Resistant Escherichia coli Isolates from Diseased Chickens and Swine in China

    OpenAIRE

    Yang, Hanchun; Chen, Sheng; White, David G.; Zhao, Shaohua; McDermott, Patrick; Walker, Robert; Meng, Jianghong

    2004-01-01

    Escherichia coli isolates from diseased piglets (n = 89) and chickens (n = 71) in China were characterized for O serogroups, virulence genes, antimicrobial susceptibility, class 1 integrons, and mechanisms of fluoroquinolone resistance. O78 was the most common serogroup identified (63%) among the chicken E. coli isolates. Most isolates were PCR positive for the increased serum survival gene (iss; 97%) and the temperature-sensitive hemagglutinin gene (tsh; 93%). The O serogroups of swine E. co...

  9. Efficient Recovery of Fluoroquinolone-Susceptible and Fluoroquinolone-Resistant Escherichia coli Strains From Frozen Samples

    OpenAIRE

    Lautenbach, Ebbing; Santana, Evelyn; Lee, Abby; Tolomeo, Pam; Black, Nicole; Babson, Andrew; Perencevich, Eli N.; Harris, Anthony D; Smith, Catherine A; Maslow, Joel

    2008-01-01

    We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only i...

  10. SCREENING THE ANTIMICROBIAL ACTIVITY OF SOME MEDICINAL PLANTS AGAINST MULTIDRUG RESISTANCE ESCHERICHIA COLI TYPE (1)

    OpenAIRE

    SHAZA ANWAR AL LAHAM, FRDOOS MOHAMMAD

    2014-01-01

    The increasing number of Escherichia coli causing mastitis and of bacteria resistant to conventional antibiotics has become aserious problem in recent years. So the search for new antibiotics and alternative products to solve this problem is the question ofthe age. This research aims to investigate the effectiveness of the extracts prepared from different parts of the following plants:Olea europea Linn (Oleaceae) ، Myrtus communis Linn (Liliaceae)، Majorana syriacus Linn (Laminaceae)، Zingibe...

  11. Nickel and Cobalt Resistance Engineered in Escherichia coli by Overexpression of Serine Acetyltransferase from the Nickel Hyperaccumulator Plant Thlaspi goesingense

    OpenAIRE

    Freeman, John L; Persans, Michael W.; Nieman, Ken; Salt, David E.

    2005-01-01

    The overexpression of serine acetyltransferase from the Ni-hyperaccumulating plant Thlaspi goesingense causes enhanced nickel and cobalt resistance in Escherichia coli. Furthermore, overexpression of T. goesingense serine acetyltransferase results in enhanced sensitivity to cadmium and has no significant effect on resistance to zinc. Enhanced nickel resistance is directly related to the constitutive overactivation of sulfur assimilation and glutathione biosynthesis, driven by the overproducti...

  12. Plasmid and Host Strain Characteristics of Escherichia coli Resistant to Extended-Spectrum Cephalosporins in the Norwegian Broiler Production

    OpenAIRE

    Solveig Sølverød Mo; Jannice Schau Slettemeås; Einar Sverre Berg; Madelaine Norström; Marianne Sunde

    2016-01-01

    Escherichia coli resistant to extended-spectrum cephalosporins have been detected in the Norwegian broiler production, despite the fact that antimicrobial agents are rarely used. The genetic mechanism responsible for cephalosporin resistance is mainly attributed to the presence of the bla CMY-2 gene encoding a plasmid-mediated AmpC-beta-lactamase (pAmpC). The aim of this study was to characterize and compare bla CMY-2 containing Escherichia coli isolated from the intestinal flora of broilers ...

  13. Lytic phages obscure the cost of antibiotic resistance in Escherichia coli.

    Science.gov (United States)

    Tazzyman, Samuel J; Hall, Alex R

    2015-04-01

    The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under phage parasitism, the likelihood that antibiotic-resistant genetic backgrounds spread depends on their initial frequency, mutation rate and intrinsic growth rate relative to drug-susceptible genotypes, because these parameters determine relative rates of phage-resistance evolution on different genetic backgrounds. Moreover, the average cost of antibiotic resistance in terms of intrinsic growth in the antibiotic-free experimental environment was small relative to the benefits of an increased mutation rate in the presence of phages. This is consistent with our theoretical work indicating that, under phage selection, typical costs of antibiotic resistance can be outweighed by realistic increases in mutability if drug resistance and hypermutability are genetically linked, as is frequently observed in clinical isolates. This suggests the long-term distribution of antibiotic resistance depends on the relative rates at which different lineages adapt to other types of selection, which in the case of phage parasitism is probably extremely common, as well as costs of resistance inferred by classical in vitro methods. PMID:25268496

  14. A novel, double mutation in DNA gyrase A of Escherichia coli conferring resistance to quinolone antibiotics.

    OpenAIRE

    Truong, Q C; Nguyen Van, J C; Shlaes, D; Gutmann, L; Moreau, N J

    1997-01-01

    A spontaneous Escherichia coli mutant, named Q3, resistant to nalidixic acid was obtained from a previously described clinical isolate of E. coli, Q2, resistant to fluoroquinolones but susceptible to nalidixic acid (E. Cambau, F. Bordon, E. Collatz, and L. Gutmann, Antimicrob. Agents Chemother. 37:1247-1252, 1993). Q3 harbored the mutation Asp82Gly in addition to the Gly81Asp mutation of Q2. The different mutations leading to Gly81Asp, Asp82Gly, and Gly81AspAsp82Gly were introduced into the g...

  15. Association Between Tetracycline Consumption and Tetracycline Resistance in Escherichia coli from Healthy Danish Slaughter Pigs

    DEFF Research Database (Denmark)

    Vieira, Antonio; Houe, Hans; Wegener, Henrik Caspar;

    2009-01-01

    It has been recognized that exposure to antimicrobial agents can exert a selective pressure for the emergence of antimicrobial resistance. The objective of this study was to investigate an association between the probability of isolating a tetracycline-resistant Escherichia coli isolate from the...... intestinal tract of healthy pigs and patterns of tetracycline Consumption in the herds of origin, together with other risk factors. Data oil antimicrobial resistance, antimicrobial consumption, and pig herd demographics were obtained from different Danish surveillance programs. Descriptive statistics were...... performed for the risk factors in relation to the susceptibility status. Logistic regression analysis was performed to identify risk factors with significant effect on the log odds of tetracycline resistance of E. coli isolates. The model showed that an increase in the interval between last prescription and...

  16. The in vitro fitness cost of antimicrobial resistance in Escherichia coli varies with the growth conditions

    DEFF Research Database (Denmark)

    Petersen, Andreas; Aarestrup, Frank Møller; Olsen, John Elmerdahl

    2009-01-01

    H and at high-salt concentrations. Strains with an impaired rpoS demonstrated a reduced fitness only during growth in a high-salt concentration. In conclusion, it was demonstrated that bacterial fitness cost in association with antimicrobial resistance generally increases under stressful growth......The objective of this study was to investigate the influence of stressful growth conditions on the fitness cost of antimicrobial resistance in Escherichia coli BJ4 caused by chromosomal mutations and plasmid acquisition. The fitness cost of chromosomal streptomycin resistance increased...... conditions. However, the growth potential of bacteria with antimicrobial resistances did not increase in a straightforward manner in these in vitro experiments and is therefore probably even more difficult to predict in vivo....

  17. Antibiotic resistance in Escherichia coli isolates obtained from animals, foods and humans in Spain.

    Science.gov (United States)

    Sáenz, Y; Zarazaga, M; Briñas, L; Lantero, M; Ruiz-Larrea, F; Torres, C

    2001-10-01

    Antibiotic resistance was investigated in 474 Escherichia coli isolates recovered from animal faeces (broilers, pigs, pets, bulls and horses), human faeces (patients and healthy volunteers) and food products of animal origin. E. coli isolates (3260) recovered from human significant infectious samples were also included. There was a high frequency of nalidixic acid, ciprofloxacin and gentamicin resistance in E. coli isolates from broilers (88, 38 and 40%, respectively), and from foods (53, 13 and 17%). High levels of resistance to trimethoprim-sulphamethoxazole and tetracycline have been found in E. coli isolates from broilers, pigs and foods. These data raise important questions about the potential impact of antibiotic use in animals and the possible entry of resistant pathogens into the food chain. PMID:11691568

  18. Multirresistência antimicrobiana em cepas de Escherichia coli isoladas de cadelas com piometra Antimicrobial multi-resistance of Escherichia coli strains isolated from bitches with pyometra

    Directory of Open Access Journals (Sweden)

    V.M. Lara

    2008-08-01

    Full Text Available The antimicrobial sensibility of Escherichia coli strains isolated from the uterine content of bitches was evaluated. Fifteen E. coli strains were tested in relation to their susceptibility to different antimicrobials. The results demonstrated 100% of resistance to all tested drugs, being a quite conflicting finding compared to other works, which observed variable resistance of those bacteria to different antimicrobials but not the same multi-resistance pattern. The detection of those multi-resistance strains configures a problem, with important implications on the antimicrobial therapy. Therefore, additional investigations for a best characterization and extension of this problem are needed.

  19. Antibiotic Resistance Pattern Of Bacterial Pathogens Isolated From Poultry Manure Used To Fertilize Fish Ponds In New Bussa, Nigeria

    Directory of Open Access Journals (Sweden)

    Funso Omojowo

    2013-02-01

    Full Text Available This study was carried out to isolate and identify antibiotic resistant bacteria from poultry manure usually used for pond fertilization. Poultry manure from 120 Chickens in National Institute for Freshwater Fisheries Research (NIFFR integrated fish farms, New-Bussa, Nigeria was collected. Five bacterial pathogens; Salmonella typhi, Escherichia coli, Shigella dysenteriae, Staphylococcus aureus and Aeromonas hydrophila were isolated. Antibiotic susceptibility testing carried out using the disk diffusion technique. Antibiotics used were; ofloxacin, amoxicillin, tetracycline, ampicillin, erythromycin, gentamicin, nalidixic acid and chloramphenicol. All the isolated organisms were 100% sensitive to ofloxacin. The multiple resistance pattern revealed that 100% were resistant to tetracycline, 84.34% resistant to ampicillin, 76.68% resistant to amoxicillin, 66% resistant to chloramphenicol, 66% resistant to gentamicin, 29% resistant to erythromycin, 28.34% resistant to nalidixic acid. The risk posed by untreated poultry manure used in fish pond fertilization and the public health implications of these results were discussed.

  20. Class 1 and 2 integrons, sul resistance genes and antibiotic resistance in Escherichia coli isolated from Dongjiang River, South China

    International Nuclear Information System (INIS)

    Antibiotic susceptibility, detection of sul gene types and presence of class 1, 2 and 3 integrons and gene cassettes using PCR assays were investigated in 3456 Escherichia coli isolates obtained from 38 sampling sites of the Dongjiang River catchment in the dry and wet seasons. 89.1% of the isolates were resistant and 87.5% showed resistance to at least three antibiotics. sul2 was detected most frequently in 89.2% of 1403 SXT-resistant isolates. The presence of integrons (class 1 and 2) was frequently observed (82.3%) while no class 3 integron was found. In these integrons, 21 resistance genes of 14 gene cassette arrays and 10 different families of resistance genes were identified. Three gene cassette arrays, aac(6')-Ib-cr-aar-3-dfrA27-aadA16, aacA4-catB3-dfrA1 and aadA2-lnuF, were detected for the first time in surface water. The results showed that bacterial resistance in the catchment was seriously influenced by human activities, especially discharge of wastewater. Highlights: ► Antibiotic resistance was investigated for a river catchment of southern China. ► 87.5% of E coli isolates showed resistance to at least three antibiotics. ► The presence of integrons (class 1 and 2) was frequently observed (82.3%). ► Bacterial resistance in the catchment was seriously influenced by human activities. - Bacterial resistance to antibiotics in a catchment is related to the discharge of wastewater into the aquatic environment.

  1. Expression of Aeromonas caviae ST pyruvate dehydrogenase complex components mediate tellurite resistance in Escherichia coli

    International Nuclear Information System (INIS)

    Potassium tellurite (K2TeO3) is harmful to most organisms and specific mechanisms explaining its toxicity are not well known to date. We previously reported that the lpdA gene product of the tellurite-resistant environmental isolate Aeromonas caviae ST is involved in the reduction of tellurite to elemental tellurium. In this work, we show that expression of A. caviae ST aceE, aceF, and lpdA genes, encoding pyruvate dehydrogenase, dihydrolipoamide transacetylase, and dihydrolipoamide dehydrogenase, respectively, results in tellurite resistance and decreased levels of tellurite-induced superoxide in Escherichia coli. In addition to oxidative damage resulting from tellurite exposure, a metabolic disorder would be simultaneously established in which the pyruvate dehydrogenase complex would represent an intracellular tellurite target. These results allow us to widen our vision regarding the molecular mechanisms involved in bacterial tellurite resistance by correlating tellurite toxicity and key enzymes of aerobic metabolism.

  2. Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, C.E.; Alvarez, H.J.; Ortiz, N.; Bisbal, M.; Arias, W.; Baerga, C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Dept. of Biology; Hazen, T.C. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.

    1988-12-31

    High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. The high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.

  3. Prevalence and characterization of antimicrobial-resistant Escherichia coli isolated from conventional and organic vegetables.

    Science.gov (United States)

    Kim, Sara; Woo, Gun-Jo

    2014-10-01

    To compare the characteristics and to identify the epidemiological relationships of Escherichia coli isolated from organic and conventional vegetables, the antimicrobial resistance and genetic properties of E. coli were investigated from 2010 to 2011. E. coli was isolated from 1 of 111 (0.9%) organic vegetables and from 20 of 225 (8.9%) conventional vegetables. The majority of strains were isolated from the surrounding farming environment (n=27/150 vs. 49/97 in organic vs. conventional samples). The majority of the vegetable strains were isolated from the surrounding farming environments. E. coli isolated from organic vegetables showed very low antimicrobial resistance rates except for cephalothin, ranging from 0% to 17.9%, while the resistance rates to cephalothin (71%) were extremely high in both groups. E. coli isolates expressed various resistance genes, which most commonly included blaTEM, tet(A), strA, strB, and qnrS. However, none of the isolates harbored tet(D), tet(E), tet(K), tet(L), tet(M), or qnrA. The transferability of tet gene, tet(A), and tet(B) was identified in tetracycline-resistant E. coli, and the genetic relationship was confirmed in a few cases from different sources. With regard to the lower antimicrobial resistance found in organic produce, this production mode seems able to considerably reduce the selection of antimicrobial-resistant bacteria on vegetables. PMID:25140978

  4. Complete Genome Sequences of Escherichia coli O157:H7 Strains SRCC 1675 and 28RC, Which Vary in Acid Resistance

    Science.gov (United States)

    Baranzoni, Gian Marco; Reichenberger, Erin R.; Kim, Gwang-Hee; Breidt, Frederick; Kay, Kathryn; Oh, Deog-Hwan

    2016-01-01

    The level of acid resistance among Escherichia coli O157:H7 strains varies, and strains with higher resistance to acid may have a lower infectious dose. The complete genome sequences belonging to two strains of Escherichia coli O157:H7 with different levels of acid resistance are presented here. PMID:27469964

  5. Induction of Antimicrobial Resistance in Escherichia coli and Non-Typhoidal Salmonella Strains after Adaptation to Disinfectant Commonly Used on Farms in Vietnam

    Science.gov (United States)

    Nhung, Nguyen T.; Thuy, Cao T.; Trung, Nguyen V.; Campbell, James; Baker, Stephen; Thwaites, Guy; Hoa, Ngo T.; Carrique-Mas, Juan

    2015-01-01

    In Vietnam, commercial disinfectants containing quaternary ammonium compounds (QACs) are commonly used in pig and poultry farms to maintain hygiene during production. We hypothesized that sustained exposure to sub-bactericidal concentrations of QAC-based disinfectants may result in increased levels of antimicrobial resistance (AMR) among Enterobacteriacea due to the increase of efflux pump expression. To test this hypothesis we exposed six antimicrobial-susceptible Escherichia coli (E. coli) and six antimicrobial-susceptible non-typhoidal Salmonella (NTS) isolates to increasing concentrations of a commonly used commercial disinfectant containing a mix of benzalkonium chloride and glutaraldehyde. Over the 12-day experiment, strains exhibited a significant change in their minimum inhibitory concentration (MIC) of the disinfectant product (mean increase of 31% (SD ± 40)) (p = 0.02, paired Wilcoxon test). Increases in MIC for the disinfectant product were strongly correlated with increases in MIC (or decreases in inhibition zone) for all antimicrobials (Pearson’s correlation coefficient 0.71–0.83, all p < 0.01). The greatest increases in MIC (or decreases in inhibition zone) were observed for ampicillin, tetracycline, ciprofloxacin, and chloramphenicol, and the smallest for gentamicin, trimethoprim/sulphamethoxazole. The treatment of 155 representative E. coli isolates from farmed and wild animals in the Mekong Delta (Vietnam) with phenyl-arginine beta-naphthylamide (PAβN), a generic efflux pump inhibitor, resulted in reductions in the prevalence of AMR ranging from 0.7% to 3.3% in these organisms, indicating a small contribution of efflux pumps on the observed prevalence of AMR on farms. These results suggest that the mass usage of commercial disinfectants, many of which contain QACs, is potentially a contributing factor on the generation and maintenance of AMR in animal production in Vietnam. PMID:27025637

  6. Induction of Antimicrobial Resistance in Escherichia coli and Non-Typhoidal Salmonella Strains after Adaptation to Disinfectant Commonly Used on Farms in Vietnam

    Directory of Open Access Journals (Sweden)

    Nguyen T. Nhung

    2015-10-01

    Full Text Available In Vietnam, commercial disinfectants containing quaternary ammonium compounds (QACs are commonly used in pig and poultry farms to maintain hygiene during production. We hypothesized that sustained exposure to sub-bactericidal concentrations of QAC-based disinfectants may result in increased levels of antimicrobial resistance (AMR among Enterobacteriacea due to the increase of efflux pump expression. To test this hypothesis we exposed six antimicrobial-susceptible Escherichia coli (E. coli and six antimicrobial-susceptible non-typhoidal Salmonella (NTS isolates to increasing concentrations of a commonly used commercial disinfectant containing a mix of benzalkonium chloride and glutaraldehyde. Over the 12-day experiment, strains exhibited a significant change in their minimum inhibitory concentration (MIC of the disinfectant product (mean increase of 31% (SD ± 40 (p = 0.02, paired Wilcoxon test. Increases in MIC for the disinfectant product were strongly correlated with increases in MIC (or decreases in inhibition zone for all antimicrobials (Pearson’s correlation coefficient 0.71–0.83, all p < 0.01. The greatest increases in MIC (or decreases in inhibition zone were observed for ampicillin, tetracycline, ciprofloxacin, and chloramphenicol, and the smallest for gentamicin, trimethoprim/sulphamethoxazole. The treatment of 155 representative E. coli isolates from farmed and wild animals in the Mekong Delta (Vietnam with phenyl-arginine beta-naphthylamide (PAβN, a generic efflux pump inhibitor, resulted in reductions in the prevalence of AMR ranging from 0.7% to 3.3% in these organisms, indicating a small contribution of efflux pumps on the observed prevalence of AMR on farms. These results suggest that the mass usage of commercial disinfectants, many of which contain QACs, is potentially a contributing factor on the generation and maintenance of AMR in animal production in Vietnam.

  7. Genetic Features of MCR-1-Producing Colistin-Resistant Escherichia coli Isolates in South Africa.

    Science.gov (United States)

    Poirel, Laurent; Kieffer, Nicolas; Brink, Adrian; Coetze, Jennifer; Jayol, Aurélie; Nordmann, Patrice

    2016-07-01

    A series of colistin-resistant Escherichia coli clinical isolates was recovered from hospitalized and community patients in South Africa. Seven clonally unrelated isolates harbored the mcr-1 gene located on different plasmid backbones. Two distinct plasmids were fully sequenced, and identical 2,600-bp-long DNA sequences defining a mcr-1 cassette were identified. Promoter sequences responsible for the expression of mcr-1, deduced from the precise identification of the +1 transcription start site for mcr-1, were characterized. PMID:27161623

  8. Efficient Recovery of Fluoroquinolone-Susceptible and Fluoroquinolone-Resistant Escherichia coli Strains From Frozen Samples

    Science.gov (United States)

    Lautenbach, Ebbing; Santana, Evelyn; Lee, Abby; Tolomeo, Pam; Black, Nicole; Babson, Andrew; Perencevich, Eli N.; Harris, Anthony D.; Smith, Catherine A.; Maslow, Joel

    2010-01-01

    We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only in low numbers in the initial sample. These findings emphasize the utility of frozen surveillance samples. PMID:18279070

  9. Virulence factors and drug resistance in Escherichia coli isolated from extraintestinal infections

    Directory of Open Access Journals (Sweden)

    Sharma S

    2007-01-01

    Full Text Available Purpose: To determine the virulence factors produced by Escherichia coli isolated from extraintestinal infections, to study the drug resistance pattern in E. coli with special reference to extended spectrum β -lactamase (ESBL and to evaluate screening methods for ESBL. Methods: A total of 152 isolates of E. coli from various extraintestinal infections were screened for virulence factors such as haemolysin, surface hydrophobicity, serum resistance and protease. All the isolates were also studied for antibiotic susceptibility pattern using modified Kirby Bauer disk diffusion method. ESBL production was screened by standard disk diffusion method and confirmed using phenotypic confirmatory method. Results: Among 152 isolates, 36 (23.7% were haemolytic, 42 (27.6% were hydrophobic, 132 (86.8% were serum resistant and only four were positive for protease. Multiple virulence factor were observed in 67 (44% of isolates. Seventy-nine (51.4% isolates produced ESBL. ESBL producing isolates showed multidrug resistance. There was a significant association ( P < 0.001 between multiple virulence factors and ESBL production by extraintestinal E. coli . Conclusions: The present study shows the expression of virulence factors and multidrug resistance in E. coli isolated from various extraintestinal infections. The study also shows that appropriate methods of detecting drug resistance and ESBL production are required for the judicious use of antibiotics in managing these infections.

  10. Antibiotic resistance and integrons in Shiga toxin-producing Escherichia coli (STEC

    Directory of Open Access Journals (Sweden)

    Rocío Colello

    2015-03-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC cause hemorrhagic colitis (HC and hemolytic-uremic syndrome in humans (HUS. Cattle are the main reservoir of STEC and transmission to humans occurs through contaminated food and water. Antibiotics are used in pig production systems to combat disease and improve productivity and play a key role in the dissemination of antibiotic resistance genes to the bacteria. Integrons have been identified in resistant bacteria allowing for the acquisition and dissemination of antibiotic resistance genes. STEC strains isolated from humans and animals have developed antibiotic resistance. In our laboratory, 21 non-157 STEC strains isolated from pigs were analyzed to detect class 1 and 2 integrons by PCR. Eight carried integrons, 7 of them harbored intl2. In another study 545 STEC strains were also analyzed for the presence of intl1 and intl2. Strains carrying intl1 belonged to isolates from environment (n = 1, chicken hamburger (n = 2, dairy calves (n = 4 and pigs (n = 8. Two strains isolated from pigs harbored intl2 and only one intl1/intl2, highlighting the presence of intl2 in pigs. The selection for multiresistant strains may contribute to the emergence of antibiotic resistant pathogens and facilitate the spreading of the mobile resistance elements to other bacteria.

  11. Antibiotic resistance and integrons in Shiga toxin-producing Escherichia coli (STEC)

    Science.gov (United States)

    Colello, Rocío; Etcheverría, Analía I.; Conza, Jose A. Di; Gutkind, Gabriel O.; Padola, Nora L.

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) cause hemorrhagic colitis (HC) and hemolytic-uremic syndrome in humans (HUS). Cattle are the main reservoir of STEC and transmission to humans occurs through contaminated food and water. Antibiotics are used in pig production systems to combat disease and improve productivity and play a key role in the dissemination of antibiotic resistance genes to the bacteria. Integrons have been identified in resistant bacteria allowing for the acquisition and dissemination of antibiotic resistance genes. STEC strains isolated from humans and animals have developed antibiotic resistance. In our laboratory, 21 non-157 STEC strains isolated from pigs were analyzed to detect class 1 and 2 integrons by PCR. Eight carried integrons, 7 of them harbored intl2. In another study 545 STEC strains were also analyzed for the presence of intl1 and intl2 . Strains carrying intl1 belonged to isolates from environment (n = 1), chicken hamburger (n = 2), dairy calves (n = 4) and pigs (n = 8). Two strains isolated from pigs harbored intl2 and only one intl1 / intl2 , highlighting the presence of intl2 in pigs. The selection for multiresistant strains may contribute to the emergence of antibiotic resistant pathogens and facilitate the spreading of the mobile resistance elements to other bacteria. PMID:26221083

  12. Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh

    OpenAIRE

    Islam Rezuanul; Parvez Anowar; Rahman Shahedur; Khan Mahboob

    2011-01-01

    Abstract Background Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Methods Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli i...

  13. 21 CFR 520.90a - Ampicillin capsules.

    Science.gov (United States)

    2010-04-01

    ... animals with a history of an allergic reaction to any of the penicillins. Ampicillin is contraindicated in... penicillins. Ampicillin is contraindicated in infections caused by penicillinase-producing organisms. Not...

  14. Drugs Susceptibility Reactions Patterns and Multiple Drug Resistance of Escherichia coli Isolated from Diarrhoeic Calves in Sudan

    Directory of Open Access Journals (Sweden)

    E.D.M. ElAmin

    2007-01-01

    Full Text Available Drug sensitivity test was performed on forty-four E. coli isolates using nine antimicrobial drugs. The latter were ampicillin, chloramphenicol, erythromycin, gentamycin, nalidixic acid, neomycin, streptomycin, sulfamethoxazole/trimethoprim and tetracycline. A considerable variation in their pattern of sensitivity was shown. Almost all isolates showed sensitivity to chloramphnicol. On the other hand, the strains were all insensitive to erythromycin. Forty-one patterns of drug susceptibility reactions were obtained. Each pattern was represented by a single strain with the exception of three of them which included two strains each.On the whole, 26 patterns of drugs resistance that ranged between resistance to a single drug and seven drugs were encountered A scheme of drug susceptibility patterns is put forward for use in routine clinical diagnosis as well as epidemiological investigations.

  15. Prevalence and risk factor analysis of resistant Escherichia coli urinary tract infections in the emergency department.

    Directory of Open Access Journals (Sweden)

    Bailey AM

    2013-06-01

    Full Text Available Background: Escherichia coli (E. coli is a frequent uropathogen in urinary tract infections (UTI. Widespread resistance to sulfamethoxazole-trimethoprim (SMX-TMP and increasing resistance to fluoroquinolones amongst these isolates has been recognized. There are limited data demonstrating risk factors for resistance to both SMX-TMP and fluoroquinolones.Objectives: This study was conducted to assess for the prevalence of community resistance amongst E. coli isolates to SMX-TMP and levofloxacin in ambulatory patients discharged from the emergency department (ED.Methods: Adults presenting for evaluation and discharged from the ED with a diagnosis of an E. coli UTI were retrospectively reviewed. Utilizing demographic and clinical data the prevalence of E. coli resistance and risk factors associated with SMX-TMP- and fluoroquinolone-resistant infection were determined. Results: Among the 222 patients, the mean rates of E. coli susceptibility to levofloxacin and SMX-TMP were 82.4% and 72.5%, respectively. Significant risk factors for resistance to SMX-TMP included prior antibiotic use (p=0.04 and prior diagnosis of UTI (p= 0.01. Significant risk factors for resistance to levofloxacin included: male gender, age, presence of hypertension, diabetes, chronic respiratory disease, nursing home resident, previous antibiotic use, previous diagnosis of UTI, existence of renal or genitourinary abnormalities, and prior surgical procedures (p <0.05 for all comparisons. The number of hospital days prior to initial ED evaluation (p<0.001 was determined to be a predictive factor in hospital and ED readmission. Conclusions: These results suggest that conventional approaches to monitoring for patterns of susceptibility may be inadequate. It is imperative that practitioners develop novel approaches to identifying patients with risk factors for resistance. Identification of risk factors from this evaluation should prompt providers to scrutinize the use of these agents in

  16. Impact of ceftiofur injection on gut microbiota and Escherichia coli resistance in pigs.

    Science.gov (United States)

    Fleury, M A; Mourand, G; Jouy, E; Touzain, F; Le Devendec, L; de Boisseson, C; Eono, F; Cariolet, R; Guérin, A; Le Goff, O; Blanquet-Diot, S; Alric, M; Kempf, I

    2015-09-01

    Resistance to extended-spectrum cephalosporins (ESCs) is an important health concern. Here, we studied the impact of the administration of a long-acting form of ceftiofur on the pig gut microbiota and ESC resistance in Escherichia coli. Pigs were orally inoculated with an ESC-resistant E. coli M63 strain harboring a conjugative plasmid carrying a gene conferring resistance, bla CTX-M-1. On the same day, they were given or not a unique injection of ceftiofur. Fecal microbiota were studied using quantitative PCR analysis of the main bacterial groups and quantification of short-chain fatty acids. E. coli and ESC-resistant E. coli were determined by culture methods, and the ESC-resistant E. coli isolates were characterized. The copies of the bla CTX-M-1 gene were quantified. After ceftiofur injection, the main change in gut microbiota was the significant but transitory decrease in the E. coli population. Acetate and butyrate levels were significantly lower in the treated group. In all inoculated groups, E. coli M63 persisted in most pigs, and the bla CTX-M-1 gene was transferred to other E. coli. Culture and PCR results showed that the ceftiofur-treated group shed significantly more resistant strains 1 and 3 days after ESC injection. Thereafter, on most dates, there were no differences between the groups, but notably, one pig in the nontreated group regularly excreted very high numbers of ESC-resistant E. coli, probably leading to a higher contamination level in its pen. In conclusion, the use of ESCs, and also the presence of high-shedding animals, are important features in the spread of ESC resistance. PMID:26077254

  17. Enhanced Survival of Rifampin- and Streptomycin-Resistant Escherichia coli Inside Macrophages.

    Science.gov (United States)

    Durão, Paulo; Gülereşi, Daniela; Proença, João; Gordo, Isabel

    2016-07-01

    The evolution of multiple-antibiotic-resistant bacteria is an increasing global problem. Even though mutations causing resistance usually incur a fitness cost in the absence of antibiotics, the magnitude of such costs varies across environments and genomic backgrounds. We studied how the combination of mutations that confer resistance to rifampin (Rif(r)) and streptomycin (Str(r)) affects the fitness of Escherichia coli when it interacts with cells from the immune system, i.e., macrophages (Mϕs). We found that 13 Rif(r) Str(r) doubly resistant genotypes, of the 16 tested, show a survival advantage inside Mϕs, indicating that double resistance can be highly beneficial in this environment. Our results suggest that there are multiple paths to acquire multiple-drug resistance in this context, i.e., if a clone carrying Rif(r) allele H526 or S531 acquires a second mutation conferring Str(r), the resulting double mutant has a high probability of showing increased survival inside Mϕs. On the other hand, we found two cases of sign epistasis between mutations, leading to a significant decrease in bacterial survival. Remarkably, infection of Mϕs with one of these combinations, K88R+H526Y, resulted in an altered pattern of gene expression in the infected Mϕs. This indicates that the fitness effects of resistance may depend on the pattern of gene expression of infected host cells. Notwithstanding the benefits of resistance found inside Mϕs, the Rif(r) Str(r) mutants have massive fitness costs when the bacteria divide outside Mϕs, indicating that the maintenance of double resistance may depend on the time spent within and outside phagocytic cells. PMID:27161646

  18. Draft Genome Sequence of Vancomycin-Susceptible, Ampicillin-Intermediate Enterococcus faecium Strain D344RRF

    Science.gov (United States)

    Rice, Louis B.

    2016-01-01

    Enterococcus faecium is an important nosocomial pathogen, causing a substantial health burden due to high resistance to antibiotics and its ability to colonize the gastrointestinal tract. Here, we present the draft genome of vancomycin-susceptible, ampicillin-intermediate strain D344RRF, a rifampicin/fusidic acid-resistant and commonly used laboratory strain, which is useful in studying the transfer of antibiotic resistance. PMID:27151809

  19. Genotypic and Phenotypic Characterization of Antimicrobial-Resistant Escherichia coli from Farm-Raised Diarrheic Sika Deer in Northeastern China

    OpenAIRE

    Li, Rui; He, Liang; Hao, Lili; Wang, Qi; Zhou, Yu; Jiang, Hongchen

    2013-01-01

    In China, overuse and/or abuse of antimicrobials are common in stockbreeding, which possess high risks of antimicrobial-resistant contaminations. The serogroups, major virulence genes, and antimicrobial resistant patterns of the antimicrobial-resistant Escherichia coli (E. coli) were investigated in the feces of diarrheic farm-raised sika deer from 50 farms in three Northeastern provinces of China. A total of 220 E. coli isolates were obtained and characterized. Twenty-eight O serogroups were...

  20. [Role of constitutive and inducible repair in radiation resistance of Escherichia coli].

    Science.gov (United States)

    Gulevich, E P; Kuznetsova, V N; Verbenko, V N

    2011-07-01

    Radiation resistance of Escherichia coil cells depends on how efficiently DNA is recovered after damage, which is determined by the function of constitutive and inducible repair branches. The effects of additional mutations of the key genes of constitutive and inducible repair (recA, lexA, recB, polA, lig, gyr, recE, recO, recR, recJ, recQ, uvrD, helD, recN, and ruv) on radiation resistance were studied in E. coli K-12 strain AB 1157 and highly radiation-resistant isogenic strain Gam(r)444. An optimal balance ensuring a high gamma resistance of the Gam(r)444 radiation-resistant E. coli mutant was due to expression of the key SOS repair genes (recA, lexA, recN, and ruv) and activation of the presynaptic functions of the RecF homologous recombination pathway as a result of a possible mutation of the uvrD gene, which codes for repair helicase II. PMID:21938951

  1. Risk factors for antimicrobial resistance in Escherichia coli found in GB turkey flocks.

    Science.gov (United States)

    Jones, E M; Snow, L C; Carrique-Mas, J J; Gosling, R J; Clouting, C; Davies, R H

    2013-11-01

    Four models are presented investigating risks present on Great Britain (GB) turkey farms in breeding and fattening flocks for ciprofloxacin and cephalosporin resistance. Risk factors for ciprofloxacin resistance in fattening flocks were sourcing of feed from national compounders, antimicrobial use in the flock and evidence of mice. Disinfection of floors and walls at depopulation, older flocks and division of the flock with partitions reduced the risk. In breeding farms holding over 10,000 birds, administration of fluoroquinolones within the last year and horses on the neighbouring farm all increased the risk, whereas replenishing foot dips more than once a week reduced the risk. For cephalosporin-resistant Escherichia coli on fattening farms, being an independent farm, having a watercourse near the poultry houses, dividing the flock with partitions and providing staff with gloves reduced the risk. Factors that increased the risk included if staff worked with other livestock and if there were pigs on neighbouring farms. This work suggests that good hygiene and biosecurity, rodent control and responsible use of antimicrobials on turkey farms might help minimise the prevalence of fluoroquinolone and cephalosporin resistance in E coli, and restrict the spread of resistance genes to other organisms. PMID:24097819

  2. Virulence and plasmidic resistance determinants of Escherichia coli isolated from municipal and hospital wastewater treatment plants.

    Science.gov (United States)

    Calhau, Vera; Mendes, Catarina; Pena, Angelina; Mendonça, Nuno; Da Silva, Gabriela Jorge

    2015-06-01

    Escherichia coli is simultaneously an indicator of water contamination and a human pathogen. This study aimed to characterize the virulence and resistance of E. coli from municipal and hospital wastewater treatment plants (WWTPs) in central Portugal. From a total of 193 isolates showing reduced susceptibility to cefotaxime and/or nalidixic acid, 20 E. coli with genetically distinct fingerprint profiles were selected and characterized. Resistance to antimicrobials was determined using the disc diffusion method. Extended spectrum β-lactamase and plasmid-mediated quinolone resistance genes, phylogroups, pathogenicity islands (PAIs) and virulence genes were screened by polymerase chain reaction (PCR). CTX-M producers were typed by multilocus sequence typing. Resistance to beta-lactams was associated with the presence of bla(TEM), bla(SHV), bla(CTX-M-15) and bla(CTX-M-32). Plasmid-mediated quinolone resistance was associated with qnrA, qnrS and aac(6')-Ib-cr. Aminoglycoside resistance and multidrug-resistant phenotypes were also detected. PAI IV(536), PAI II(CFT073), PAI II(536) and PAI I(CFT073), and uropathogenic genes iutA, papAH and sfa/foc were detected. With regard to the clinical ST131 clone, it carried bla(CTX-M-15), blaTEM-type, qnrS and aac(6')-lb-cr; IncF and IncP plasmids, and virulence factors PAI IV(536), PAI I(CFT073), PAI II(CFT073), iutA, sfa/foc and papAH were identified in the effluent of a hospital plant. WWTPs contribute to the dissemination of virulent and resistant bacteria in water ecosystems, constituting an environmental and public health risk. PMID:26042965

  3. Antimicrobial-resistant faecal Escherichia coli in wild mammals in central Europe: multiresistant Escherichia coli producing extended-spectrum ß-lactamases in wild boars

    DEFF Research Database (Denmark)

    Literak, I.; Dolejska, Monika; Radimersky, T.;

    2010-01-01

    Aims: To determine the presence of antibiotic-resistant faecal Escherichia coli in populations of wild mammals in the Czech Republic and Slovakia. Methods and Results: Rectal swabs or faeces collected during 2006-2008 from wild mammals were spread on MacConkey agar and MacConkey agar containing 2...... mg l-1 of cefotaxime. From plates with positive growth, one isolate was recovered and identified as E. coli. Susceptibility to 12 antibiotics was tested using the disk diffusion method. Resistance genes, class 1 and 2 integrons and gene cassettes were detected in resistant isolates by polymerase...... prevalence of resistant isolates was 2% in small terrestrial mammals (rodents and insectivores, n(E. coli) = 242), 12% in wild ruminants and foxes (n(E. coli) = 42), while no resistant isolates were detected in brown bears (n(E. coli) = 16). In wild boars (Sus scrofa) (n(E. coli) = 290), the prevalence of...

  4. CORRELATION BETWEEN BIOFILM FORMATION OF UROPATHOGE NIC ESCHERICHIA COLI AND ITS ANTIBIOTIC RESISTANCE PATT ERN

    Directory of Open Access Journals (Sweden)

    SarojGolia

    2012-09-01

    Full Text Available ABSTRACT BACKGROUND: Microorganisms growing in multilayered cell cluste rs embedded in a matrix of extracellular polysaccharide (slime which facilitat es the adherence of these microorganisms to biomedical surfaces and protect them from host immun e system and antimicrobial therapy. There are various methods to detect biofilm producti on like Tissue Culture Plate (TCP ,Tube method (TM ,Modified Congo Red Agar Method (MCRA, bio luminescent assay ,piezoelectric sensors and fluorescent microscopic examination. OBJECTIVES : This study was conducted to compare three methods f or the detection of biofilms and compare with antibiotic sensitivity pat tern, in uropathogenic Escherichia coli. METHOD: This study was carried out at the Department of Microbiology Dr. B. R. Ambedkar Medical College from Dec 2011 to June 2012. Total n umber of 107 clinical Escherichia coli isolates were randomly selected from all age groups were subjected to biofilm detection methods and their antibiotic resistance pattern w as compared. Isolates were identified by standard phenotypic methods. Biofilm detection was te sted by TCP, TM and MCRA methods . Antibiotic susceptibility test of uropathogenic E co li was performed using Kirby –Bauer disc diffusion method according to CLSI guidelines. RESULTS: From the total of 107 clinical isolate 74 (69.1 % isolates showed biofilm formation by all the TCP, TM, CRP methods. Biofilm forming i solates from catheter associated UTI showed drug resistance to more than 6 drugs. Only 2(13.3% isolates from Asymptomatic UTI showed biofilm by TM & MCRA methods & were sensitive all d rugs. Biofilm forming isolates from symptomatic UTI showed mixed drug resistance pattern. CONCLUSION: We conclude from our study that biofilm formation is more common in catheterized patients. TCP method is more quantitati ve and reliable method for the detection of biofilm forming micro-organisms as compared to TM a nd MCRA methods. So TCP method can be recommended

  5. SCREENING THE ANTIMICROBIAL ACTIVITY OF SOME MEDICINAL PLANTS AGAINST MULTIDRUG RESISTANCE ESCHERICHIA COLI TYPE (1

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    SHAZA ANWAR AL LAHAM, FRDOOS MOHAMMAD

    2014-05-01

    Full Text Available The increasing number of Escherichia coli causing mastitis and of bacteria resistant to conventional antibiotics has become aserious problem in recent years. So the search for new antibiotics and alternative products to solve this problem is the question ofthe age. This research aims to investigate the effectiveness of the extracts prepared from different parts of the following plants:Olea europea Linn (Oleaceae ، Myrtus communis Linn (Liliaceae، Majorana syriacus Linn (Laminaceae، Zingiber officinaleLinn (Zingiberaceae، Achillea falcata Linn (Asteraceae against resistant Escherichia coli Type (1. Investigation began forE.coli bacteria in 667 milk samples. The bacteria were identified culturally, morphologically and biochemically. Antibioticsusceptibility testing against E.coli by Kirby-Bauer disk diffusion method were conducted. Then using the blood agar,MacConkey agar, salmonella - shigella agar, and biochemical testing method [API 20 E testing Enterobacteriaceae] were made totype E.coli. Plants were extracted with water, absolute alcohol, then ether using a soxhlet apparatus and rotary vacuumevaporator. Then extracts susceptibility testing against antibiotic resistant E.coli Type (1 were studied. E. coli was defined asoxidase negative, indole positive, catalase positive. The studied antibiotics did not show any antibacterial effect against E.coli .By the results of the biochemical analysis (API20e on resistant E.coli , E.coli type (1 was 33.35% of the total number ofsamples. The anti-bacterial effectiveness against E.coli type (1 of ethanol extracts prepared from different parts of the studiedplants were variant, whereas the Myrtus communis extract effectively has the most powerful antibacterial effect for these bacteria,while the Zingiber officinale extract has the lowest influence.

  6. The Chromosomal Arsenic Resistance Genes of Thiobacillus ferrooxidans Have an Unusual Arrangement and Confer Increased Arsenic and Antimony Resistance to Escherichia coli

    OpenAIRE

    Butcher, Bronwyn G.; Deane, Shelly M.; Rawlings, Douglas E.

    2000-01-01

    The chromosomal arsenic resistance genes of the acidophilic, chemolithoautotrophic, biomining bacterium Thiobacillus ferrooxidans were cloned and sequenced. Homologues of four arsenic resistance genes, arsB, arsC, arsH, and a putative arsR gene, were identified. The T. ferrooxidans arsB (arsenite export) and arsC (arsenate reductase) gene products were functional when they were cloned in an Escherichia coli ars deletion mutant and conferred increased resistance to arsenite, arsenate, and anti...

  7. A comparative trial of pivmecillinam and ampicillin in bacteriuria of pregnancy.

    Science.gov (United States)

    Bint, A; Bullock, D; Reeves, D; Wilkinson, P

    1979-01-01

    A comparative trial of pivmecillinam and ampicillin was performed on 100 women with bacteriuria of pregnancy. They received either 400 mg pivmecillinam four times daily or 500 mg ampicillin four times daily for seven days. Cure rates at two weeks were 88% in the pivmecillinam group and 85% in the ampicillin group. At six weeks the respective rates were 76% and 64%. Failure of therapy was not associated with the appearance of bacterial resistance in either treatment group. Side-effects, particularly vomiting and premature cessation of therapy, were significantly more frequent in the pivmecillinam group. No significant effects on liver function were found. In subsequent patients treated in a non-comparative manner with 200 mg pivmecillinam three times daily, the incidence of side effects was markedly reduced with no loss of efficacy. PMID:232697

  8. The serum resistome of a globally disseminated multidrug resistant uropathogenic Escherichia coli clone.

    Directory of Open Access Journals (Sweden)

    Minh-Duy Phan

    Full Text Available Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for a high proportion of urinary tract and bloodstream infections. The rapid emergence and successful spread of E. coli ST131 is strongly associated with antibiotic resistance; however, this phenotype alone is unlikely to explain its dominance amongst multidrug resistant uropathogens circulating worldwide in hospitals and the community. Thus, a greater understanding of the molecular mechanisms that underpin the fitness of E. coli ST131 is required. In this study, we employed hyper-saturated transposon mutagenesis in combination with multiplexed transposon directed insertion-site sequencing to define the essential genes required for in vitro growth and the serum resistome (i.e. genes required for resistance to human serum of E. coli EC958, a representative of the predominant E. coli ST131 clonal lineage. We identified 315 essential genes in E. coli EC958, 231 (73% of which were also essential in E. coli K-12. The serum resistome comprised 56 genes, the majority of which encode membrane proteins or factors involved in lipopolysaccharide (LPS biosynthesis. Targeted mutagenesis confirmed a role in serum resistance for 46 (82% of these genes. The murein lipoprotein Lpp, along with two lipid A-core biosynthesis enzymes WaaP and WaaG, were most strongly associated with serum resistance. While LPS was the main resistance mechanism defined for E. coli EC958 in serum, the enterobacterial common antigen and colanic acid also impacted on this phenotype. Our analysis also identified a novel function for two genes, hyxA and hyxR, as minor regulators of O-antigen chain length. This study offers novel insight into the genetic make-up of E. coli ST131, and provides a framework for future research on E. coli and other Gram-negative pathogens to define their essential gene repertoire and to dissect the molecular mechanisms that enable them to survive in the bloodstream and

  9. Prevalence of multi-drug resistant uropathogenic Escherichia coli in Potohar region of Pakistan

    Institute of Scientific and Technical Information of China (English)

    Ihsan Ali; Zara Rafaque; Safia Ahmed; Sajid Malik; Javid Iqbal Dasti

    2016-01-01

    Objective: To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli (UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract infections. Methods: Bacterial samples (n = 250) were collected from out-patients from August 2012 to August 2014 Islamabad. Antibiotic susceptibility profiling and determination of mini-mum inhibitory concentrations (MICs) and minimum bactericidal concentrations were performed according to the guidelines of Clinical and Laboratory Standards Institute (CLSI, 2012). Genes, qnrA, qnrB and qnrS were identified by DNA amplification and sequencing. Results: The highest percentage of UPEC isolates were resistant to co-trimoxazole (82%) followed by cephalothin (80%), 2nd Gen, 3rd Gen and 4th Gen cephalosporins, respectively. Resistance against gentamicin, amikacin remained 29% and 4%. For other drugs including nitrofurantoin, tetracycline, carbapenem and beta-lactam inhibitors remained below 10%. Altogether, 59% of the isolates were resistant to at least three antibiotics including one fluoroquinolone. Overall, MICs for ciprofloxacin remained (MIC≥256 mg/mL) and for levofloxacin (MIC≥16 mg/mL and 32 mg/mL). No significant differences were observed regarding MIC values of extended spectrum b-lactamase (ESBL) and non-ESBL producers. For qnrS and qnrB positive isolates MICs remained above 32 mg/mL. Prevalence of UPEC was significantly higher among females and 40% of the isolates were ESBL producers. Conclusions: Higher percentages of ESBL producing UPEC were associated with uri-nary tract infections. Moreover, the majority of these isolates were multi-drug resistant and fluoroquinolone-resistant.

  10. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    NARCIS (Netherlands)

    V.T. Nguyen; J.J. Carrique-Mas; T.H Ngo; H.M. Ho; T.T. Ha; J.I. Campbell; T.N. Nguyen; N.N. Hoang; V.M. Pham; J.A. Wagenaar; A. Hardon; Q.H. Thai; C. Schultsz

    2015-01-01

    Objectives: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. Methods:

  11. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    NARCIS (Netherlands)

    Trung, Nguyen Vinh; Carrique-Mas, Juan J; Thi Hoa, Ngo; Mai, Ho Huynh; Tuyen, Ha Thanh; Campbell, James I; Nhung, Nguyen Thi; Nhung, Hoang Ngoc; Van Minh, Pham; Wagenaar, Jaap A; Hardon, Anita; Hieu, Thai Quoc; Schultsz, Constance

    2015-01-01

    OBJECTIVES: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. METHODS:

  12. Susceptibility of multidrug resistant enterotoxigenic escherichia coli to saponin extract from phyllanthus niruri

    International Nuclear Information System (INIS)

    Escherichia coli were isolated from 140 samples of blood, urine, stool and water made up of 15.7%, 42.9% and 30.0% and 25.7% respectively. From the samples, 71.9% enterotoxigenic E. coli (ETEC), 14.3% enteropathogenic E. coli (EPEC), 7.1% enterohemorrhagic E. coil (EHEC) and 7.1% enteroinvasive E. coli (EIEC) occurred as diarrheagenic E. coli. Of the ETEC (240) isolates tested for susceptibility to eight conventional antibiotics. 110 (46.0%) showed resistance to all the tested antimicrobial agents. However, of the resistant strains; 24 (22.0%) were multidrug resistant. These were tested against 3.0 mg/mL of saponin extract from phyllanthus niruri and 13 (55.0%) of these were susceptible to the saponin. The antimicrobial activities of saponin from P. niruri are of interest since the crude extract was effective at concentration of 3.0 mg/ml to multiple resistant isolates of EEC. (author)

  13. Prevalence of antimicrobial resistance in Escherichia coli and Klebsiella spp. in rural South India.

    Science.gov (United States)

    Sekar, Ramalingam; Mythreyee, Manoharan; Srivani, Seetharaman; Amudhan, Murugesan

    2016-06-01

    The emergence and dissemination of antimicrobial resistance (AMR) is an important public health problem as resistant organisms cause difficult-to-treat infections. In this study, the prevalence of AMR in Escherichia coli and Klebsiella spp. in rural South India was examined in order to aid empirical therapy. A cross-sectional prospective study was conducted during the period from January 2012 to December 2014. Routine clinical isolates of E. coli and Klebsiella spp. were tested for antimicrobial susceptibility to β-lactams, aminoglycosides, fluoroquinolones, tetracyclines, colistin and nitrofurantoin by the Kirby-Bauer disk diffusion method and the data were documented and analyzed with one per patient analysis using WHONET software. A total of 2292 non-duplicate clinical isolates were recovered during the study period, including 1338 E. coli and 954 Klebsiella spp. The prevalence of AMR in the total isolates was as follows: amikacin, 17.3%; ertapenem, 14.4%; doripenem, 4.5%; colistin, 13.2%; and tigecycline, 4.1%. The study results indicate a high prevalence of carbapenem resistance in Klebsiella spp. especially from pus and urinary isolates, whilst the prevalence of aztreonam and fluoroquinolone resistance was very high in E. coli. PMID:27436473

  14. Characterization of Multidrug Resistant ESBL-Producing Escherichia coli Isolates from Hospitals in Malaysia

    Directory of Open Access Journals (Sweden)

    King-Ting Lim

    2009-01-01

    Full Text Available The emergence of Escherichia coli that produce extended spectrum β-lactamases (ESBLs and are multidrug resistant (MDR poses antibiotic management problems. Forty-seven E. coli isolates from various public hospitals in Malaysia were studied. All isolates were sensitive to imipenem whereas 36 were MDR (resistant to 2 or more classes of antibiotics. PCR detection using gene-specific primers showed that 87.5% of the ESBL-producing E. coli harbored the blaTEM gene. Other ESBL-encoding genes detected were blaOXA, blaSHV, and blaCTX-M. Integron-encoded integrases were detected in 55.3% of isolates, with class 1 integron-encoded intI1 integrase being the majority. Amplification and sequence analysis of the 5′CS region of the integrons showed known antibiotic resistance-encoding gene cassettes of various sizes that were inserted within the respective integrons. Conjugation and transformation experiments indicated that some of the antibiotic resistance genes were likely plasmid-encoded and transmissible. All 47 isolates were subtyped by PFGE and PCR-based fingerprinting using random amplified polymorphic DNA (RAPD, repetitive extragenic palindromes (REPs, and enterobacterial repetitive intergenic consensus (ERIC. These isolates were very diverse and heterogeneous. PFGE, ERIC, and REP-PCR methods were more discriminative than RAPD in subtyping the E. coli isolates.

  15. Cloning and expression of the Legionella micdadei "common antigen" in Escherichia coli

    DEFF Research Database (Denmark)

    Bangsborg, Jette Marie; Collins, M T; Høiby, N;

    1989-01-01

    To study individual Legionella antigens, a Legionella micdadei genomic library in Escherichia coli SC181 was established. Partially Sau3A digested L. micdadei DNA fragments (15-25 kilobase pairs (kb] were cloned into the tetracycline resistance gene of the cosmid vector pHC79. Four thousand...... ampicillin resistant recombinants were obtained; seven hundred were screened for expression of Legionella antigens in Western blot analysis with a polyspecific E. coli-absorbed anti-L. micdadei rabbit antibody. One of the positive clones expressed a 60 kilodalton (K) antigen, which reacted strongly with a...

  16. Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations in quinolone-resistant Escherichia coli isolated from humans and swine in Denmark

    DEFF Research Database (Denmark)

    Cavaco, Lina; Frimodt-Møller, Niels; Hasman, Henrik;

    2008-01-01

    Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were investigated in 124 Escherichia coli isolated from humans (n = 85) and swine (n = 39) in Denmark. The collection included 59 high-level CIP......-resistant isolates (MIC >= 4) from human (n = 51) and pig origin (n = 8) and 65 low-level CIP-resistant isolates (MIC >= 0.125) from human (n = 34) and pig origin (n = 31). Resistance by target modification was screened by PCR amplification and sequencing, of the quinolone resistance determining regions (QRDRs) of......A and qnrS genes conferring quinolone resistance by target protection were detected in two human low-level CIP-resistant isolates that did not display NAL resistance. As expected, target mutation in QRDRs was the most prevalent mechanism of quinolone resistance. This mechanism was complemented by efflux...

  17. ANTIMICROBIAL DRUG RESISTANCE IN STRAINS OF Escherichia coli ISOLATED FROM FOOD SOURCES

    Directory of Open Access Journals (Sweden)

    Mohammed Uddin Rasheed

    2014-07-01

    Full Text Available A variety of foods and environmental sources harbor bacteria that are resistant to one or more antimicrobial drugs used in medicine and agriculture. Antibiotic resistance in Escherichia coli is of particular concern because it is the most common Gram-negative pathogen in humans. Hence this study was conducted to determine the antibiotic sensitivity pattern of E. coli isolated from different types of food items collected randomly from twelve localities of Hyderabad, India. A total of 150 samples comprising; vegetable salad, raw egg-surface, raw chicken, unpasteurized milk, and raw meat were processed microbiologically to isolate E. coli and to study their antibiotic susceptibility pattern by the Kirby-Bauer method. The highest percentages of drug resistance in isolates of E. coli were detected from raw chicken (23.3% followed by vegetable salad (20%, raw meat (13.3%, raw egg-surface (10% and unpasteurized milk (6.7%. The overall incidence of drug resistant E. coli was 14.7%. A total of six (4% Extended Spectrum β-Lactamase (ESBL producers were detected, two each from vegetable salads and raw chicken, and one each from raw egg-surface and raw meat. Multidrug resistant strains of E. coli are a matter of concern as resistance genes are easily transferable to other strains. Pathogen cycling through food is very common and might pose a potential health risk to the consumer. Therefore, in order to avoid this, good hygienic practices are necessary in the abattoirs to prevent contamination of cattle and poultry products with intestinal content as well as forbidding the use of untreated sewage in irrigating vegetables.

  18. Antibiotic resistance and prevalence of Enterococcus spp. and Escherichia coli isolated from bryndza cheese

    Directory of Open Access Journals (Sweden)

    Marek Vrabec

    2015-10-01

    Full Text Available The study aimed at determining the prevalence antibiotic resistance of species – identified enterococci and Escherichia (E. coli isolated from typical fresh Slovak cheese, bryndza. Antibiotic resistance of enterococci was determined by disk diffusion method. Of isolated enterococci, 240 were obtained from bryndza cheese. The first two decimal dilutions from 24 bryndza cheese samples purchased at supermarkets in Košice (0.1 mL were spread on the surface of Slanetz and Bartley agar and incubated for 48±2 h at 37±1ºC. Species identification of enterococci and E. coli was detected by means of matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF MS based on bacterial protein profiling. The following species of enterococci were identified by MALDI-TOF MS: Enterococcus (Ent. faecalis (22 strains, Ent. faecium (18 strains, Ent. sacharolyticus (6 strains, Ent. gilvus (4 strains, Ent. durans (9 strains, and Ent. casseliflavus (6 strains. All of the 45 E. coli strains and 74 strains of enterococci identified by MALDI-TOF MS were determined for occurrence of blaTEM, blaSHV and blaCTX-M genes. The results of our study suggest that the highest resistance of enterococci was on tetracycline (29.73% and any resistance was recorded on vancomycin (0%. The highest multidrug-resistance was recorded on two antibiotics (32.43%. Neither one isolate of enterococci was resistant to all 6 antibiotics used in the experiment. In total, 19 (42.22% E. coli were found to be producers of extended-spectrum β-lactamase.

  19. Spanish multicenter study of the epidemiology and mechanisms of amoxicillin-clavulanate resistance in Escherichia coli.

    Science.gov (United States)

    Ortega, Adriana; Oteo, Jesús; Aranzamendi-Zaldumbide, Maitane; Bartolomé, Rosa M; Bou, Germán; Cercenado, Emilia; Conejo, M Carmen; González-López, Juan José; Marín, Mercedes; Martínez-Martínez, Luis; Merino, María; Navarro, Ferran; Oliver, Antonio; Pascual, Alvaro; Rivera, Alba; Rodríguez-Baño, Jesús; Weber, Irene; Aracil, Belén; Campos, José

    2012-07-01

    We conducted a prospective multicenter study in Spain to characterize the mechanisms of resistance to amoxicillin-clavulanate (AMC) in Escherichia coli. Up to 44 AMC-resistant E. coli isolates (MIC ≥ 32/16 μg/ml) were collected at each of the seven participant hospitals. Resistance mechanisms were characterized by PCR and sequencing. Molecular epidemiology was studied by pulsed-field gel electrophoresis (PFGE) and by multilocus sequence typing. Overall AMC resistance was 9.3%. The resistance mechanisms detected in the 257 AMC-resistant isolates were OXA-1 production (26.1%), hyperproduction of penicillinase (22.6%), production of plasmidic AmpC (19.5%), hyperproduction of chromosomic AmpC (18.3%), and production of inhibitor-resistant TEM (IRT) (17.5%). The IRTs identified were TEM-40 (33.3%), TEM-30 (28.9%), TEM-33 (11.1%), TEM-32 (4.4%), TEM-34 (4.4%), TEM-35 (2.2%), TEM-54 (2.2%), TEM-76 (2.2%), TEM-79 (2.2%), and the new TEM-185 (8.8%). By PFGE, a high degree of genetic diversity was observed although two well-defined clusters were detected in the OXA-1-producing isolates: the C1 cluster consisting of 19 phylogroup A/sequence type 88 [ST88] isolates and the C2 cluster consisting of 19 phylogroup B2/ST131 isolates (16 of them producing CTX-M-15). Each of the clusters was detected in six different hospitals. In total, 21.8% of the isolates were serotype O25b/phylogroup B2 (O25b/B2). AMC resistance in E. coli is widespread in Spain at the hospital and community levels. A high prevalence of OXA-1 was found. Although resistant isolates were genetically diverse, clonality was linked to OXA-1-producing isolates of the STs 88 and 131. Dissemination of IRTs was frequent, and the epidemic O25b/B2/ST131 clone carried many different mechanisms of AMC resistance. PMID:22491692

  20. Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh

    Directory of Open Access Journals (Sweden)

    Islam Rezuanul

    2011-03-01

    Full Text Available Abstract Background Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Methods Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh. Results All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm. Conclusion Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary.

  1. Pharmacodynamics of ampicillin sodium transdermal patches in an in vitro infection model

    Directory of Open Access Journals (Sweden)

    Bagyalakshmi J

    2006-01-01

    Full Text Available The purpose of this study was to examine the activity of ampicillin sodium developed as transdermal patch against Escherichia coli . In the present work, the efficiency of ampicillin sodium against E. coli was investigated in an in vitro infection model which simulates human pharmacokinetics. The E. coli stains were exposed to transdermal patch with different kinds of polymers such as sodium alginate, cellulose acetate phthalate, hydroxypropylmethylcellulose, chitosan and carboxymethylcellulose and the drug releasing capacity was studied through colony-forming units (CFU. The process was carried out for 24 h at 37°. It was found out that hydroxypropylmethylcellulose was the best polymer that gave less number of CFU, followed by carboxyl methyl cellulose, chitosan, cellulose acetate phthalate and sodium alginate.

  2. Identification of a novel plasmid-mediated colistin-resistance gene, mcr-2, in Escherichia coli, Belgium, June 2016.

    Science.gov (United States)

    Xavier, Basil Britto; Lammens, Christine; Ruhal, Rohit; Kumar-Singh, Samir; Butaye, Patrick; Goossens, Herman; Malhotra-Kumar, Surbhi

    2016-07-01

    We identified a novel plasmid-mediated colistin-resistance gene in porcine and bovine colistin-resistant Escherichia coli that did not contain mcr-1. The gene, termed mcr-2, a 1,617 bp phosphoethanolamine transferase harboured on an IncX4 plasmid, has 76.7% nucleotide identity to mcr-1. Prevalence of mcr-2 in porcine colistin-resistant E. coli (11/53) in Belgium was higher than that of mcr-1 (7/53). These data call for an immediate introduction of mcr-2 screening in ongoing molecular epidemiological surveillance of colistin-resistant Gram-negative pathogens. PMID:27416987

  3. Quantitative assessment of faecal shedding of β-lactam-resistant Escherichia coli and enterococci in dogs

    DEFF Research Database (Denmark)

    Gongora, Carmen Espinosa; Shah, Syed Qaswar Ali; Jessen, Lisbeth Rem; Bortolaia, Valeria; Langebæk, Rikke; Bjørnvad, Charlotte Reinhard; Guardabassi, Luca

    Quantitative data on faecal shedding of antimicrobial resistant bacteria are crucial to assess the risk of transmission from dogs to other animals as well as humans. In this study we investigated prevalence and concentrations of β-lactam-resistant Escherichia coli and enterococci in the faeces of....../g). Cefotaxime resistance was associated with the presence of blaCTX-M-1 (n=4), blaCMY-2 (n=4) or multiple mutations in the promoter and coding region of chromosomal ampC (n=1). Altogether the results indicate that the risks of zoonotic transmission of β-lactam-resistant bacteria via human exposure to canine...

  4. AmpC β-Lactamase in an Escherichia coli Clinical Isolate Confers Resistance to Expanded-Spectrum Cephalosporins

    OpenAIRE

    Mammeri, Hedi; Nazic, Hasan; Naas, Thierry; Poirel, Laurent; Léotard, Sophie; Nordmann, Patrice

    2004-01-01

    Cloning, sequencing, and biochemical analysis identified a novel AmpC-type β-lactamase conferring resistance to extended-spectrum cephalosporins in an Escherichia coli clinical isolate. This enzyme, exhibiting 14 amino acid substitutions compared to a reference AmpC cephalosporinase of E. coli, hydrolyzed ceftazidime and cefepime significantly.

  5. Quinolone resistance and ESBL/AmpC’s in commensal Escherichia coli in veal calves : prevalence and molecular characterization

    NARCIS (Netherlands)

    Hordijk, J.

    2013-01-01

    In this thesis the prevalence and molecular characteristics of resistance to (fluoro)quinolones and Extended Spectrum Cephalosporins (ESC) in veal calves were described using Escherichia coli as an indicator organism. Ciprofloxacin and nalidixic acid were used as indicator antimicrobials for quinolo

  6. Persistence of Escherichia coli clones and phenotypic and genotypic antibiotic resistance in recurrent urinary tract infections in childhood

    DEFF Research Database (Denmark)

    Kõljalg, Siiri; Truusalu, Kai; Vainumäe, Inga;

    2009-01-01

    We assessed the clonality of consecutive Escherichia coli isolates during the course of recurrent urinary tract infections (RUTI) in childhood in order to compare clonality with phenotypic antibiotic resistance patterns, the presence of integrons, and the presence of the sul1, sul2, and sul3 gene...

  7. Lysogenic Conversion and Phage Resistance Development in Phage Exposed Escherichia coli Biofilms

    Directory of Open Access Journals (Sweden)

    Abram Aertsen

    2013-01-01

    Full Text Available In this study, three-day old mature biofilms of Escherichia coli were exposed once to either a temperate Shiga-toxin encoding phage (H-19B or an obligatory lytic phage (T7, after which further dynamics in the biofilm were monitored. As such, it was found that a single dose of H-19B could rapidly lead to a near complete lysogenization of the biofilm, with a subsequent continuous release of infectious H-19B particles. On the other hand, a single dose of T7 rapidly led to resistance development in the biofilm population. Together, our data indicates a profound impact of phages on the dynamics within structured bacterial populations.

  8. Molecular epidemiological study on tetracycline resistance R plasmids in enterohaemorrhagic Escherichia coli O157:H7.

    Science.gov (United States)

    Makino, S; Asakura, H; Obayashi, T; Shirahata, T; Ikeda, T; Takeshi, K

    1999-08-01

    Restriction patterns obtained with EcoRI and Southern hybridization were used for the differentiation of tetracycline-resistant (Tet(r)) R plasmids in enterobaemorrhagic Escherichia coli (EHEC) O157:H7 isolates from a mass outbreak at a kindergarten in Obihiro-City, Hokkaido, Japan, 1996. Two kinds of Tet(r) R plasmids of 50 and 95 kb were detected. The 50-kb plasmids were identical to each other, while the 93-kb plasmids were of three types that were very similar to each other. The tet genes of both 50- and 95-kb R plasmids were 100% identical to the tet gene of pSC101 and all plasmids hybridized to a probe for tet. Because food-origin O157 strains were sensitive to tetracycline, we concluded that such Tet(r) R-plasmids might transfer to drug-sensitive O157 strains in the infected individuals. PMID:10487638

  9. Molecular epidemiological study on tetracycline resistance R plasmids in enterohaemorrhagic Escherichia coli O157:H7.

    Science.gov (United States)

    Makino, S.; Asakura, H.; Obayashi, T.; Shirahata, T.; Ikeda, T.; Takeshi, K.

    1999-01-01

    Restriction patterns obtained with EcoRI and Southern hybridization were used for the differentiation of tetracycline-resistant (Tet(r)) R plasmids in enterobaemorrhagic Escherichia coli (EHEC) O157:H7 isolates from a mass outbreak at a kindergarten in Obihiro-City, Hokkaido, Japan, 1996. Two kinds of Tet(r) R plasmids of 50 and 95 kb were detected. The 50-kb plasmids were identical to each other, while the 93-kb plasmids were of three types that were very similar to each other. The tet genes of both 50- and 95-kb R plasmids were 100% identical to the tet gene of pSC101 and all plasmids hybridized to a probe for tet. Because food-origin O157 strains were sensitive to tetracycline, we concluded that such Tet(r) R-plasmids might transfer to drug-sensitive O157 strains in the infected individuals. PMID:10487638

  10. Lysogenic conversion and phage resistance development in phage exposed Escherichia coli biofilms.

    Science.gov (United States)

    Moons, Pieter; Faster, David; Aertsen, Abram

    2013-01-01

    In this study, three-day old mature biofilms of Escherichia coli were exposed once to either a temperate Shiga-toxin encoding phage (H-19B) or an obligatory lytic phage (T7), after which further dynamics in the biofilm were monitored. As such, it was found that a single dose of H-19B could rapidly lead to a near complete lysogenization of the biofilm, with a subsequent continuous release of infectious H-19B particles. On the other hand, a single dose of T7 rapidly led to resistance development in the biofilm population. Together, our data indicates a profound impact of phages on the dynamics within structured bacterial populations. PMID:23344561

  11. MOLECULAR-PHYLOGENETIC CHARACTERIZATION AND ANTIMICROBIAL RESISTANCE OF Escherichia coli ISOLATED FROM GOATS WITH DIARRHEA

    Directory of Open Access Journals (Sweden)

    Rodrigo Almeida Guimarães

    2015-10-01

    Full Text Available Neonatal diarrhea determines significant changes in feed conversion, causing productivity loss in caprine herds. The antimicrobial resistance in bacteria is characterized as an important public health issue; therefore, Escherichia coli may be characterized as an important pathogen due to expressing virulence mechanisms responsible for significant clinical conditions in humans and animals. The present study evaluated the presence of E. coli among 117 caprine fecal samples and analyzed the isolates for antimicrobial resistance. Suggestive colonies were submitted to biochemical screening followed by genotypic group determination and phylogenetic analysis; further, the samples were submitted to antimicrobials susceptibility test. E. coli, Salmonella spp, Shigella sonnei and Enterobacter aerogenes were identified. E. coli isolates were phylogenetically classified as B2 (9/39, D (19/39, B1 (7/39 e A (4/29 groups. The analysis of the isolates also revealed the presence of K99 (04/39 and Stx (02/39 virulence factors. Antimicrobial susceptibility test revealed sensitive isolates to Chloramphenicol, Streptomycin, Amoxicillin and Ciprofloxacin, being all resistant to Lincomycin, Vancomycin and Penicillin. The results support the need of establishing restricted protocols for antimicrobial use, a fundamental procedure for health improvement in Brazilian caprine herds.

  12. Expanded Genetic Codes Create New Mutational Routes to Rifampicin Resistance in Escherichia coli.

    Science.gov (United States)

    Hammerling, Michael J; Gollihar, Jimmy; Mortensen, Catherine; Alnahhas, Razan N; Ellington, Andrew D; Barrick, Jeffrey E

    2016-08-01

    Until recently, evolutionary questions surrounding the nature of the genetic code have been mostly limited to the realm of conjecture, modeling, and simulation due to the difficulty of altering this fundamental property of living organisms. Concerted genome and protein engineering efforts now make it possible to experimentally study the impact of alternative genetic codes on the evolution of biological systems. We explored how Escherichia coli strains that incorporate a 21st nonstandard amino acid (nsAA) at the recoded amber (TAG) stop codon evolve resistance to the antibiotic rifampicin. Resistance to rifampicin arises from chromosomal mutations in the β subunit of RNA polymerase (RpoB). We found that a variety of mutations that lead to substitutions of nsAAs in the essential RpoB protein confer robust rifampicin resistance. We interpret these results in a framework in which an expanded code can increase evolvability in two distinct ways: by adding a new letter with unique chemical properties to the protein alphabet and by altering the mutational connectivity of amber-adjacent codons by converting a lethal nonsense mutation into a missense mutation. Finally, we consider the implications of these results for the evolution of alternative genetic codes. In our experiments, reliance on a mutation to a reassigned codon for a vital trait is not required for the long-term maintenance of an expanded genetic code and may even destabilize incorporation of an nsAA, a result that is consistent with the codon capture model of genetic code evolution. PMID:27189550

  13. Mutant radiation-resistance alleles from the Escherichia coli Gamr444 mutant: Cloning and preliminary characterization

    International Nuclear Information System (INIS)

    Mutant alleles Gamr, which are able to increase the resistance to radiation of Escherichia coli wild-type cells, were cloned from the hyperradioresistant mutant Gamr444 on plasmid mini-Mu-vector MudII4042. The influence of recombinant plasmids on the sensitivity of wild-type and mutant (recA and htpR) cells to γ-irradiation was studied. It was shown that the enhanced resistance of the Gamr444 strain to radiation was caused by mutations of two different classes, dominant and recessive. The cloned recessive mutation gamr12 increases resistance to radiation only after homogenotization, that is, radiation-induced transfer from the plasmid to the chromosome, and it imposes constitutive expression of the heat-shock promoter htpG. Dominant mutant gamr alleles are active in the trans-position. A mutation-insertion into a chromosomal gene impaired by one of the dominant mutations, gamr18, was constructed. The insertion causes drastic cell radiosensitization on the recBC sbcB background and probably disturbs the RecF pathway of recombination and repair. Dominant plasmids of the second type lead to the RecA-independent inhibition of DNA postirradiation degradation. The radioprotective action of recessive and dominant gamr mutations is additive

  14. Antimicrobial-resistant patterns of Escherichia coli and Salmonella strains in the aquatic Lebanese environments

    International Nuclear Information System (INIS)

    This study is the first to be conducted in Lebanon on the isolation and molecular characterization and the antimicrobial resistance profile of environmental pathogenic bacterial strains. Fifty-seven samples of seawater, sediment, crab, and fresh water were collected during the spring and summer seasons of 2003. The isolation of Escherichia coli and Salmonella using appropriate selective media revealed that 94.7% of the tested samples were contaminated with one or both of the tested bacteria. The polymerase chain reaction (PCR) was then used to identify the species of both bacteria using various sets of primers. Many pathogenic E. coli isolates were detected by PCR out of which two were identified as O157:H7 E. coli. Similarly, the species of many of the Salmonella isolates was molecularly identified. The confirmed isolates of Salmonella and E. coli were then tested using the disk diffusion method for their susceptibility to four different antimicrobials revealing high rates of antimicrobial resistance. - First report of antibiotic resistance in bacteria in the environment in Lebanon

  15. Cefotaxime-resistant Escherichia coli in broiler farms-A cross-sectional investigation in Germany.

    Science.gov (United States)

    Hering, Johanna; Frömke, Cornelia; von Münchhausen, Christiane; Hartmann, Maria; Schneider, Bettina; Friese, Anika; Rösler, Uwe; Kreienbrock, Lothar; Hille, Katja

    2016-03-01

    In this investigation the farm prevalence of cefotaxime-resistant Escherichia coli (CREC) in German broiler farms was evaluated. In total, 59 flocks on 34 broiler farms were sampled in four agricultural regions of Germany. Per broiler flock, three faecal samples, a pair of boot swabs and one dust sample were taken and examined for the presence of CREC. After pre-enrichment of sample material in Luria-Bertani-broth, the broth was streaked onto MacConkey agar containing 1mg/l cefotaxime (CTX). CREC isolates were detected in at least one sample from each flock resulting in a farm prevalence of 100%. The proportion of positive samples was high in all three sample types. Of 177 collective faecal samples 81.9% were positive, of 59 boot swabs and 59 dust samples 79.7% and 62.7% were positive. In conclusion, the prevalence of broiler farms with cefotaxime-resistant E. coli in Germany is very high. We suggest that the analysis of collective faecal samples is sufficient to determine the CREC farm status. In addition to other studies our study supports the finding that cefotaxime resistance is a good proxy for the presence of ESBL- or plasmidic AmpC-beta-lactamases. PMID:26783199

  16. Fluoroquinolone-resistant Escherichia coli isolated from healthy broilers with previous exposure to fluoroquinolones: Is there a link?

    OpenAIRE

    Moniri, Rezvan; Dastehgoli, Kamran

    2011-01-01

    The occurrence of resistance to quinolones and fluoroquinolones in Escherichia coli isolated from healthy chickens and its relation to previous use of fluoroquinolones in Kashan, Iran, was evaluated. A total of 181 E. coli isolates was collected. Ninety-five (52.5%) of the chickens had a history of previous use of both flumequine and enrofloxacin; 86 (47.5%) chickens had not been exposed to antimicrobial agents previously. The proportion of strains resistant to nalidixic acid and ciprofloxaci...

  17. Carbapenem-Resistant KPC-2-Producing Escherichia coli in a Tel Aviv Medical Center, 2005 to 2008▿

    OpenAIRE

    Goren, M. G.; Navon-Venezia, S.; Chmelnitsky, I.; Carmeli, Y

    2010-01-01

    All of the carbapenem-resistant Escherichia coli (CREC) isolates identified in our hospital from 2005 to 2008 (n = 10) were studied. CREC isolates were multidrug resistant, all carried blaKPC-2, and six of them were also extended-spectrum beta-lactamase producers. Pulsed-field gel electrophoresis indicated six genetic clones; within the same clone, similar transferable blaKPC-2-containing plasmids were found whereas plasmids differed between clones. Tn4401 elements were identified in all of t...

  18. Novel streptomycin and spectinomycin resistance gene as a gene cassette within a class 1 integron isolated from Escherichia coli

    DEFF Research Database (Denmark)

    Sandvang, D.

    1999-01-01

    The aadA genes, encoding resistance to streptomycin and spectinomycin, have been found as gene cassettes in different gram-negative and gram-positive bacterial species. The present study has revealed the sequence of a new gene, aadA5, integrated as a gene cassette together with the trimethoprim r...... resistance gene dfr7 in a class 1 integron. The integron was located on a plasmid and was identified in a pathogenic porcine Escherichia coli isolate....

  19. Risk factors for occurrence of cephalosporin-resistant Escherichia coli in Norwegian broiler flocks.

    Science.gov (United States)

    Mo, Solveig Sølverød; Kristoffersen, Anja Bråthen; Sunde, Marianne; Nødtvedt, Ane; Norström, Madelaine

    2016-08-01

    A longitudinal study of 27 broiler farms including 182 broiler flocks was performed to determine risk factors for occurrence of cephalosporin-resistant Escherichia coli in Norwegian broiler flocks. Information regarding possible risk factors was collected by an online questionnaire and by samples obtained from broiler and parent flocks during the study period. Additional information was provided by the broiler production company. The prevalence of cephalosporin-resistant E. coli in parent flocks and broiler flocks sampled in the study was estimated. Cephalosporin-resistant E. coli was detected in 13.8% of the parent flocks and 22.5% of the broiler flocks included in the study. A multivariable generalized linear model was used to estimate risk factors. The risk for occurrence of cephalosporin-resistant E. coli was associated with the status of the previous flock in the broiler house (odds ratio=12.7), number of parent flocks supplying the broiler flock with day-old chickens (odds ratio=6.3), routines for disinfection of floor between production cycles (odds ratio=0.1), and transport personnel entering the room where the broilers are raised (odds ratio=9.3). Our findings highlights that implementation of a high level of biosecurity with a minimal number of people entering the broiler house during production cycles, as well as rigorous cleaning and disinfection routines between production cycles will contribute to a decrease in the occurrence of cephalosporin-resistant E. coli in broiler flocks provided that there is no selection pressure from antimicrobial use in the broiler production. PMID:27435654

  20. Accumulation of ciprofloxacin and lomefloxacinin fluoroquinolone-resistant strains of Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    夏培元; 冯萍; 钟利; 吕晓菊; 雷秉钧

    2002-01-01

    Objective To evaluate the role of outer membrane protein (Omp) F-deficiency and active efflux in the accumulation of hydrophilic fluoroquinolones ciprofloxacin (CPLX) and lomefloxacin (LMLX) in resistant E. coli strains. Methods Fluoroquinolone accumulation in bacteria and the effect of active efflux were measured by a fluorescence method. The outer membrane proteins of the bacteria were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). E. coli strains in this study included control strains JF701 and JF703 that are OmpC- or OmpF-deficient mutants of E. coli K-12, respectively, and the fluoroquinolone susceptible strain the fluoroquinolone susceptible strain of Escherichia coli (Ecs) and its in vitroselected resistant strains R2 and R256, and the clinical resistant isolates R5 and R6. Results The steady-state accumulation concentration of each drug in Ecs appeared to be the same as in JF701, while in the OmpF- deficient strain JF703, it was 1/5 CPLX or 1/2 LMLX lower than that in JF701, but JF703 was still susceptible to fluoroquinolones. On the other hand, compared with susceptible strains, a 2- to 10-fold decrease in the accumulation of each drug was found in the resistant strains except R2, in which the accumulation was slightly higher than in JF703. After the addition of 2,4-dinitrophenol (DNP), accumulation of each drug increased, especially in resistant strains, indicating that the function of the active efflux (pump) system in these bacteria had been enhanced dramatically. Furthermore, both OmpF and OmpC in Ecs, OmpF-deficiency in R2 and R256 and OmpC-deficiency in R5 and R6 were observed.Conclusion The decreased accumulation of hydrophilic fluoroquinolones in E. coli involved OmpF-deficiency and active efflux (pump), and the latter may be an important factor.

  1. High-performance liquid chromatographic analysis of ampicillin.

    Science.gov (United States)

    Tsuji, K; Robertson, J H

    1975-09-01

    A high-pressure liquid chromatographic method for the analysis of ampicillin is described. The method uses a 1-m long stainless steel column packed with anionic exchange resin, with a mobile phase of 0.02 M NaNO3 in 0.01 M pH 9.15 borate buffer at a flow rate of 0.45 ml/min. The degradation products of ampicillin, penicillenic and penicilloic acids of ampicillin, can be separated and quantitated in less than 12 min of chromatographic time. The relative standard deviation for the analysis of ampicillin is less than 1%, and the method is sensitive to approximately 20 ng of ampicillin/sample injected. The method was applied to the analysis of various pharmaceutical preparations of ampicillin. It is also applicable, with a slight modification, for the analysis of penicillins G and V. PMID:1185575

  2. Adaptation mechanisms of Escherichia Coli to the ultraviolet light I. Isolation of mutants resistant to ultraviolet light

    International Nuclear Information System (INIS)

    The objective of this work is to study the adaptation mechanisms of Escherichia coli to the ultraviolet light of 254 nm (W), a component of the solar light that induces a variety of damages in the DNA of the cells exposed, which should be eliminated in order to avoid its lethal and mutagenic effects. Inside this first report, the results obtained about the resistance to UV radiation of 5 independent populations of Escherichia coli, which were subjected in parallel form to 80 successive exposures of UV light with inserted periods of growth are reported. (Author)

  3. Ampicillin-sulbactam is effective in prevention and therapy of experimental endocarditis caused by beta-lactamase-producing coagulase-negative staphylococci.

    OpenAIRE

    Ramos, M C; Ing, M; Kim, E.; Witt, M D; Bayer, A S

    1996-01-01

    Optimal strategies for the prophylaxis and therapy of endocarditis caused by oxacillin-resistant, coagulase-negative staphylococci in patients with native or prosthetic valvular heart disease are not well defined. We compared the in vivo efficacies of ampicillin-sulbactam-based regimens with those of vancomycin-based oxacillin-resistant, beta-lactamase-producing coagulase-negative staphylococcal isolate (Staphylococcus haemolyticus SE220). Ampicillin-sulbactam (100 and 20 mg/kg of body weight...

  4. Continuous-infusion ampicillin therapy of enterococcal endocarditis in rats.

    OpenAIRE

    Thauvin, C; Eliopoulos, G M; Willey, S; Wennersten, C; Moellering, R C

    1987-01-01

    Intermittent administration of ampicillin alone has resulted in high failure rates in previously described animal models of enterococcal endocarditis. We developed a rat model of enterococcal endocarditis which permits comparison of continuous intravenous infusion of ampicillin with intramuscular therapy. Continuous low-dose ampicillin infusion (450 mg/kg [body weight] per day) was compared with the same dose given intramuscularly in three divided doses and with high-dose infusion (4.5 g/kg p...

  5. The Escherichia coli BtuE protein functions as a resistance determinant against reactive oxygen species.

    Directory of Open Access Journals (Sweden)

    Felipe A Arenas

    Full Text Available This work shows that the recently described Escherichia coli BtuE peroxidase protects the bacterium against oxidative stress that is generated by tellurite and by other reactive oxygen species elicitors (ROS. Cells lacking btuE (ΔbtuE displayed higher sensitivity to K(2TeO(3 and other oxidative stress-generating agents than did the isogenic, parental, wild-type strain. They also exhibited increased levels of cytoplasmic reactive oxygen species, oxidized proteins, thiobarbituric acid reactive substances, and lipoperoxides. E. coli ΔbtuE that was exposed to tellurite or H(2O(2 did not show growth changes relative to wild type cells either in aerobic or anaerobic conditions. Nevertheless, the elimination of btuE from cells deficient in catalases/peroxidases (Hpx(- resulted in impaired growth and resistance to these toxicants only in aerobic conditions, suggesting that BtuE is involved in the defense against oxidative damage. Genetic complementation of E. coli ΔbtuE restored toxicant resistance to levels exhibited by the wild type strain. As expected, btuE overexpression resulted in decreased amounts of oxidative damage products as well as in lower transcriptional levels of the oxidative stress-induced genes ibpA, soxS and katG.

  6. IbeR facilitates stress-resistance, invasion and pathogenicity of avian pathogenic Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Shaohui Wang

    Full Text Available Systemic infections by avian pathogenic Escherichia coli (APEC are economically devastating to poultry industries worldwide. IbeR, located on genomic island GimA, was shown to serve as an RpoS-like regulator in rpoS gene mutation neonatal meningitis E. coli (NMEC RS218. However, the role of IbeR in pathogenicity of APEC carrying active RpoS has not yet been investigated. We showed that the APEC IbeR could elicit antibodies in infected ducks, suggesting that IbeR might be involved in APEC pathogenicity. To investigate the function of IbeR in APEC pathogenesis, mutant and complementation strains were constructed and characterized. Inactivation of ibeR led to attenuated virulence and reduced invasion capacity towards DF-1 cells, brains and cerebrospinal fluid (CSF in vitro and in vivo. Bactericidal assays demonstrated that the mutant strain had impaired resistance to environmental stress and specific pathogen-free (SPF chicken serum. These virulence-related phenotypes were restored by genetic complementation. Quantitative real-time reverse transcription PCR revealed that IbeR controlled expression of stress-resistance genes and virulence genes, which might led to the associated virulence phenotype.

  7. Short-Chain Chromate Ion Transporter Proteins from Bacillus subtilis Confer Chromate Resistance in Escherichia coli▿

    Science.gov (United States)

    Díaz-Magaña, Amada; Aguilar-Barajas, Esther; Moreno-Sánchez, Rafael; Ramírez-Díaz, Martha I.; Riveros-Rosas, Héctor; Vargas, Eréndira; Cervantes, Carlos

    2009-01-01

    Tandem paired genes encoding putative short-chain monodomain protein members of the chromate ion transporter (CHR) superfamily (ywrB and ywrA) were cloned from genomic DNA of Bacillus subtilis strain 168. The transcription of the paired genes, renamed chr3N and chr3C, respectively, was shown to occur via a bicistronic mRNA generated from a promoter upstream of the chr3N gene. The chr3N and chr3C genes conferred chromate resistance when expressed in Escherichia coli strain W3110. The cloned chr3N gene alone did not confer chromate resistance on E. coli, suggesting that both chr3N and chr3C genes are required for function. E. coli cells expressing paired chr3N and chr3C genes demonstrated diminished uptake of chromate compared to that by a vector-only control strain. These results suggest that short-chain CHR proteins form heterodimer transporters which efflux chromate ions from the cytoplasm. PMID:19581367

  8. The European Union Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2011

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-05-01

    Full Text Available The antimicrobial resistance data among zoonotic and indicator bacteria in 2011, submitted by 26 European Union Member States, were jointly analysed by the European Food Safety Authority and the European Centre for Disease Prevention and Control. Data covered resistance in zoonotic Salmonella and Campylobacter isolates from humans, food and animals, and in indicator Escherichia coli and enterococci isolates from animals and food. Data on methicillin-resistant Staphylococcus aureus in animals and food were also presented. Resistance in isolates from humans were mainly interpreted using clinical breakpoints, while animal and food isolate resistance was interpreted using epidemiological cut-off values. Resistance was commonly found in isolates from humans, animals and food, although disparities in resistance were frequently observed between Member States. High resistance levels were recorded to ampicillin, tetracyclines and sulfonamides in Salmonella isolates from humans, while resistance to third-generation cephalosporins and fluoroquinolones remained low. In Salmonella and indicator Escherichia coli isolates from fowl, pigs, cattle and meat thereof, resistance to ampicillin, tetracyclines and sulfonamides was also commonly detected, while resistance to third-generation cephalosporins was low. Moderate to high resistance to (fluoroquinolones was observed in Salmonella isolates from turkeys, fowl and broiler meat. In Campylobacter isolates from human cases, resistance to ampicillin, ciprofloxacin, nalidixic acid and tetracyclines was high, while resistance to erythromycin was low to moderate. High resistance to ciprofloxacin, nalidixic acid and tetracyclines was observed in Campylobacter isolates from fowl, broiler meat, pigs and cattle, whereas much lower levels were observed for erythromycin and gentamicin. Among the indicator enterococci isolates from animals and food, resistance to tetracyclines and erythromycin was commonly detected. The

  9. Antimicrobial Resistance of Faecal Escherichia coli Isolates from Pig Farms with Different Durations of In-feed Antimicrobial Use.

    Science.gov (United States)

    Gibbons, J F; Boland, F; Egan, J; Fanning, S; Markey, B K; Leonard, F C

    2016-05-01

    Antimicrobial use and resistance in animal and food production are of concern to public health. The primary aims of this study were to determine the frequency of resistance to 12 antimicrobials in Escherichia coli isolates from 39 pig farms and to identify patterns of antimicrobial use on these farms. Further aims were to determine whether a categorization of farms based on the duration of in-feed antimicrobial use (long-term versus short-term) could predict the occurrence of resistance on these farms and to identify the usage of specific antimicrobial drugs associated with the occurrence of resistance. Escherichia coli were isolated from all production stages on these farms; susceptibility testing was carried out against a panel of antimicrobials. Antimicrobial prescribing data were collected, and farms were categorized as long term or short term based on these. Resistance frequencies and antimicrobial use were tabulated. Logistic regression models of resistance to each antimicrobial were constructed with stage of production, duration of antimicrobial use and the use of 5 antimicrobial classes included as explanatory variables in each model. The greatest frequencies of resistance were observed to tetracycline, trimethoprim/sulphamethoxazole and streptomycin with the highest levels of resistance observed in isolates from first-stage weaned pigs. Differences in the types of antimicrobial drugs used were noted between long-term and short-term use farms. Categorization of farms as long- or short-term use was sufficient to predict the likely occurrence of resistance to 3 antimicrobial classes and could provide an aid in the control of resistance in the food chain. Stage of production was a significant predictor variable in all models of resistance constructed and did not solely reflect antimicrobial use at each stage. Cross-selection and co-selection for resistance was evident in the models constructed, and the use of trimethoprim/sulphonamide drugs in particular was

  10. Genetic characterization of fluoroquinolone-resistant Escherichia coli associated with bovine mastitis in India

    Directory of Open Access Journals (Sweden)

    Sangeetha Balakrishnan

    2016-07-01

    Full Text Available Aim: The present study was undertaken to characterize the mutation in gyrA (DNA gyrase and parC (topoisomerase IV genes responsible for fluoroquinolone resistance in Escherichia coli isolates associated with the bovine mastitis. Materials and Methods: A total of 92 milk samples from bovine mastitis cases were sampled in and around Puducherry (Southern India. Among these samples, 30 isolates were bacteriologically characterized as E. coli. Minimum inhibitory concentrations (MIC of fluoroquinolones of these 30 E. coli isolates were evaluated by resazurin microtiter assay. Then, the quinolone resistance determining region (QRDR (gyrA and parC genes of these E. coli isolates was genetically analyzed for determining the chromosomal mutation causing fluoroquinolone resistance. Results: E. coli isolates showed a resistance rate of 63.33%, 23.33% and 30.03% to nalidixic acid, ciprofloxacin and enrofloxacin, respectively. Mutations were found at 83rd and 87th amino acid position of gyrA gene, and at 80th and 108th amino acid position of parC gene in our study isolates. Among these five isolates, one had a single mutation at 83 amino acid position of gyrA with reduced susceptibility (0.5 μg/ml to ciprofloxacin. Then, in remaining four isolates, three isolates showed triple mutation (at gyrA: S83gL and D87gN; at parC: S80gI and the fifth isolate showed an additional mutation at codon 108 of parC (A108gT with the increased ciprofloxacin MIC of 16-128 μg/ml. The most common mutation noticed were at S83gL and D87gN of gyrA and S80gI of ParC. Conclusion: The study confirms the presence of mutation/s responsible for fluoroquinolone resistance in QRDR of gyrA and parC genes of E. coli isolates of animal origin, and there is increased rate of fluoroquinolone resistance with high-level of MIC. The mutations observed in this study were similar to that of human isolates.

  11. Antimicrobial resistance in Escherichia coli isolates from raccoons (Procyon lotor) in Southern Ontario, Canada.

    Science.gov (United States)

    Jardine, Claire M; Janecko, Nicol; Allan, Mike; Boerlin, Patrick; Chalmers, Gabhan; Kozak, Gosia; McEwen, Scott A; Reid-Smith, Richard J

    2012-06-01

    We conducted a cross-sectional study to determine the prevalence of antimicrobial resistance (AMR) in fecal Escherichia coli isolates from raccoons (Procyon lotor) living in Ontario, Canada. From June to October 2007, we trapped raccoons in three areas: one primarily urban site around Niagara, one primarily rural site north of Guelph, and one at the Toronto Zoo. In addition, we conducted a longitudinal study at the Toronto Zoo site to investigate the temporal dynamics of fecal E. coli and AMR in raccoons. Reduced susceptibility to ≥1 antimicrobial agent was detected in E. coli isolates from 19% of 16 raccoons at the urban site, 17% of 29 raccoons from the rural site, and 42% of 130 samples collected from 59 raccoons at the zoo site. Raccoons from the zoo site were significantly more likely to shed E. coli with reduced susceptibility to ≥1 antimicrobial agent than animals from the rural site (odds ratio [OR], 3.41; 95% confidence interval [CI], 1.17 to 12.09; P = 0.02). Resistance to expanded-spectrum cephalosporins (and the associated bla(CMY-2) gene) was detected in two animals from the zoo site and one animal from the rural site. Serotyping and pulsed-field gel electrophoresis analysis show that raccoons on the zoo grounds harbor a diverse assemblage of E. coli, with rapid bacterial turnover within individuals over time. Our study indicates that raccoons may shed resistant bacteria of public health significance and that raccoons have the potential to disseminate these bacteria throughout their environment. PMID:22447599

  12. Pathways of resistance to thymineless death in Escherichia coli and the function of UvrD.

    Science.gov (United States)

    Fonville, Natalie C; Vaksman, Zalman; DeNapoli, Jessica; Hastings, P J; Rosenberg, Susan M

    2011-09-01

    Thymineless death (TLD) is the rapid loss of viability in bacterial, yeast, and human cells starved of thymine. TLD is the mode of action of common anticancer drugs and some antibiotics. TLD in Escherichia coli is accompanied by blocked replication and chromosomal DNA loss and recent work identified activities of recombination protein RecA and the SOS DNA-damage response as causes of TLD. Here, we examine the basis of hypersensitivity to thymine deprivation (hyper-TLD) in mutants that lack the UvrD helicase, which opposes RecA action and participates in some DNA repair mechanisms, RecBCD exonuclease, which degrades double-stranded linear DNA and works with RecA in double-strand-break repair and SOS induction, and RuvABC Holliday-junction resolvase. We report that hyper-TLD in uvrD cells is partly RecA dependent and cannot be attributed to accumulation of intermediates in mismatch repair or nucleotide-excision repair. These data imply that both its known role in opposing RecA and an additional as-yet-unknown function of UvrD promote TLD resistance. The hyper-TLD of ruvABC cells requires RecA but not RecQ or RecJ. The hyper-TLD of recB cells requires neither RecA nor RecQ, implying that neither recombination nor SOS induction causes hyper-TLD in recB cells, and RecQ is not the sole source of double-strand ends (DSEs) during TLD, as previously proposed; models are suggested. These results define pathways by which cells resist TLD and suggest strategies for combating TLD resistance during chemotherapies. PMID:21705756

  13. Dissemination of multidrug-resistant Escherichia coli in Korean veterinary hospitals.

    Science.gov (United States)

    So, Jeong Hwa; Kim, Juwon; Bae, Il Kwon; Jeong, Seok Hoon; Kim, So Hyun; Lim, Suk-kyung; Park, Yong Ho; Lee, Kyungwon

    2012-06-01

    This study was performed to investigate the prevalence of rectal colonization with multidrug-resistant Escherichia coli in dogs hospitalized at veterinary hospitals in Korea and to assess the molecular epidemiologic traits of this organism. A total of 63 unique E. coli isolates obtained from the rectal swabs of hospitalized dogs were analyzed. Genes encoding CTX-M extended-spectrum β-lactamases (ESBLs) and AmpC enzymes were detected in 21 (33.3%) and 15 (23.8%) canine E. coli isolates, respectively. Twelve canine E. coli isolates harbored both the genes encoding the CTX-M and AmpC enzymes. Six ESBL-producing E. coli isolates also carried the rmtB gene. All 24 E. coli isolates producing CTX-M ESBL and/or CMY-2 were resistant to ciprofloxacin. Furthermore, mutations were found in the gyrA and the parC genes. In most cases, the bla genes of the CTX-M ESBL and AmpC enzymes and the rmtB gene were localized to incompatibility group F (IncF) plasmids. Possible small clonal outbreaks are suggested because some E. coli isolates recovered in the same veterinary hospital were identified as identical sequence types and showed identical banding patterns in repetitive sequence-based polymerase chain reaction. The horizontal transfer of IncF plasmids and the clonal transfer of E. coli strains are suggested to play a role in the dissemination of antimicrobial resistance genes, and this transfer may occur across host species (i.e., between humans and dogs). PMID:22516765

  14. Virulence factors, antimicrobial resistance, and plasmid content of Escherichia coli isolated in swine commercial farms Fatores de virulência, resistência aos antimicrobianos, presença de plasmídeos em Escherichia coli isoladas de amostras clínicas e ambientais de suínos

    Directory of Open Access Journals (Sweden)

    M.M. Costa

    2010-02-01

    Full Text Available Virulence factors and antimicrobial resistance patterns of Escherichia coli isolates were evaluated. A total of 80 E. coli isolates were evaluated, being 64 from clinical samples (intestinal content and fragments of organs from diarrheic piglets, seven from feces of clinically healthy piglets and sows, and nine environmental samples (five from facilities, two from feed, one from insect, and one from waste. Molecular characterization was performed by PCR detection of fimbriae and toxin genes and plasmid content determination. The isolates were also characterized according to their resistance or sensitivity to the following drugs: ampicillin, trimethoprim:sulfamethoxazole, tetracycline, amikacine, colistin, norfloxacin, florfenicol, enrofloxacin, cefalexin, trimethoprim, neomycin, chloramphenicol, and gentamicin. From 80 E. coli isolates, 53.8% were classified as enterotoxigenic E. coli (ETEC, 2.5% were shiga toxin-producing E. coli (STEC, and 43.8% showed a non specific pattern and were unclassified. One fecal isolate from non-diarrheic piglet was classified as ETEC by PCR. Clinical isolates showed resistance mainly for tetracycline and trimethoprim:sulfamethoxazole. Plasmidial DNA was observed in 70 isolates, being 78.5% of clinical isolates, 8.57% of non-diarrheic feces, and 12.8% of environment.Os fatores de virulência e a resistência aos antimicrobianos foram avaliados em Escherichia coli. Um total de 80 isolados de E. coli, sendo 64 de amostras clínicas (conteúdo intestinal e fragmentos de órgãos de leitões diarreicos, sete das fezes de porcas e leitões saudáveis e nove de amostras ambientais (cinco de instalações, dois de alimentos, um de inseto e um de esterqueira. A caracterização molecular feita pela PCR objetivou detectar fimbrias e toxinas, bem como a determinação do conteúdo de plasmídeos. Os isolados foram caracterizados quanto à resistência ou sensibilidade às seguintes drogas: ampicilina, sulfazotrim

  15. 21 CFR 522.90a - Ampicillin trihydrate sterile suspension.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ampicillin trihydrate sterile suspension. 522.90a... § 522.90a Ampicillin trihydrate sterile suspension. (a) Specifications. Each milliliter contains... to use by or on the order of a licensed veterinarian. (iv) Swine. (A) Amount. 3 milligrams per...

  16. 21 CFR 520.90b - Ampicillin trihydrate tablets.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ampicillin trihydrate tablets. 520.90b Section 520.90b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... trihydrate tablets. (a) Specifications. Each tablet contains ampicillin trihydrate equivalent to 50 or...

  17. Molecular mechanisms of antimicrobial resistance in fecal Escherichia coli of healthy dogs after enrofloxacin or amoxicillin administration.

    Science.gov (United States)

    Aly, Sherine A; Debavalya, Nipattra; Suh, Sang-Jin; Oryazabal, Omar A; Boothe, Dawn M

    2012-11-01

    Escherichia coli respond to selective pressure of antimicrobial therapy by developing resistance through a variety of mechanisms. The purpose of this study was to characterize the genetic mechanisms of antimicrobial resistance in fecal E. coli after the routine use of 2 popular antimicrobials. Fourteen resistant E. coli isolates, representing predominant clones that emerged in healthy dogs' feces after treatment with either amoxicillin (11 E. coli isolates) or enrofloxacin (3 E. coli isolates), were tested for mutations in DNA gyrase (gyrA and gyrB) and in topoisomerase IV (parC) and for the presence of β-lactamases (bla(TEM), bla(SHV), bla(PSE-1) and bla(CTX-M)) and plasmid-mediated quinolone resistance (qnrA, qnrB, qnrS, aac(6')-Ib, and qepA), by polymerase chain reaction. Escherichia coli isolates cultured following amoxicillin therapy only expressed single-drug resistance to β-lactams, while the isolates cultured from dogs receiving enrofloxacin therapy expressed multidrug resistance (MDR). The use of RND efflux pump inhibitors increased the susceptibility of the 3 MDR E. coli isolates to doxycycline, chloramphenicol, enrofloxacin, and ciprofloxacin, which indicates a role of the efflux pump in the acquisition of the MDR phenotype. Amplification and sequencing of AcrAB efflux pump regulators (soxR, soxS, marR, and acrR) revealed only the presence of a single mutation in soxS in the 3 MDR isolates. PMID:23145826

  18. Risk Factors for the Development of Gastrointestinal Colonization With Fluoroquinolone-Resistant Escherichia coli in Residents of Long-Term Care Facilities

    OpenAIRE

    Han, Jennifer H.; Maslow, Joel; Han, Xiaoyan; Xie, Sharon X; Tolomeo, Pam; Santana, Evelyn; Carson, Lesley; Lautenbach, Ebbing

    2013-01-01

    Background. The objective of this study was to assess risk factors for the development of fluoroquinolone (FQ)–resistant Escherichia coli gastrointestinal tract colonization in long-term care facility (LTCF) residents.

  19. Prevalence of Plasmid-Mediated Quinolone Resistance Genes among Ciprofloxacin-Nonsusceptible Escherichia coli and Klebsiella pneumoniae Isolated from Blood Cultures in Korea

    Directory of Open Access Journals (Sweden)

    Hee Young Yang

    2014-01-01

    Full Text Available OBJECTIVES:To analyze the prevalence of plasmid-mediated quinolone resistance (PMQR determinants in ciprofloxacin-nonsusceptible Escherichia coli and Klebsiella pneumoniae isolated from patients at a tertiary care hospital in Korea.

  20. Antimicrobial resistance trends among canine Escherichia coli isolates obtained from clinical samples in the northeastern USA, 2004–2011

    OpenAIRE

    Cummings, Kevin J.; Aprea, Victor A.; Altier, Craig

    2015-01-01

    Our objectives were to describe the antimicrobial susceptibility of Escherichia coli isolates from dogs in the northeastern USA and to identify temporal trends in resistance to selected antimicrobial agents. Data were collected retrospectively for all canine E. coli isolates from clinical samples submitted to Cornell University’s Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Antimicrobial susceptibility testing was performed on 3519 canine E. coli isolates; fr...

  1. Low minimum inhibitory concentrations associated with the tetracycline-resistance gene tet(C) in Escherichia coli

    OpenAIRE

    Chalmers, Gabhan; Kozak, Gosia K.; Hillyer, Elizabeth; Reid-Smith, Richard J.; Boerlin, Patrick

    2010-01-01

    Twenty-eight Escherichia coli isolates from various animal and environmental sources with defined tetracycline-resistance genotypes for tet(A), tet(B), and tet(C) were tested for their susceptibility to tetracycline by means of both broth microdilution and Etest. All tet(C)-positive isolates had tetracycline minimum inhibitory concentrations clustering around an intermediate susceptibility range of 2 to 16 μg/mL. Detecting tet(C)-positive isolates by means of susceptibility testing may theref...

  2. The BaeSR Two-Component Regulatory System Mediates Resistance to Condensed Tannins in Escherichia coli▿ †

    OpenAIRE

    Zoetendal, E.G.; Smith, A H; Sundset, M.A.; Mackie, R. I.

    2007-01-01

    The gene expression profiles of Escherichia coli strains grown anaerobically with or without Acacia mearnsii (black wattle) extract were compared to identify tannin resistance strategies. The cell envelope stress protein gene spy and the multidrug transporter-encoding operon mdtABCD, both under the control of the BaeSR two-component regulatory system, were significantly up-regulated in the presence of tannins. BaeSR mutants were more tannin sensitive than their wild-type counterparts.

  3. Antimicrobial Resistance, Virulence Factors and Genetic Diversity of Escherichia coli Isolates from Household Water Supply in Dhaka, Bangladesh

    OpenAIRE

    Talukdar, Prabhat Kumar; Rahman, M; Nabi, Ashikun; Islam, Zhahirul; Hoque, Mahfuzul; Endtz, Hubert

    2013-01-01

    textabstractBackground: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity. Methodology/Principal Findings: A total of 233 E. coli isolate...

  4. Quinolone- and ß-lactam-resistance in Escherichia coli from Danish and Italian broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne;

    Quinolone- and ß-lactam-resistance in Escherichia coli from Danish and Italian broiler flocks Valeria Bortolaia1, Luca Guardabassi1, Magne Bisgaard1, Marcello Trevisani2, Anders Miki Bojesen1   1Department of Veterinary Pathobiology, Faculty of Life Sciences, University of Copenhagen, DK-1870 Fre...... fluoroquinolones and cephalosporins in the Italian poultry production is higher compared to the Danish. Accordingly, the results of this study could reflect the different policies in antimicrobial usage between the two countries....

  5. High Prevalence of Class 1 to 3 Integrons Among Multidrug-Resistant Diarrheagenic Escherichia coli in Southwest of Iran

    OpenAIRE

    Kargar, Mohammad; Mohammadalipour, Zahra; Doosti, Abbas; Lorzadeh, Shahrokh; Japoni-Nejad, Alireza

    2014-01-01

    Objectives Horizontal transfer of integrons is one of the important factors that can contribute to the occurrence of multidrug-resistant (MDR) bacteria. This study aimed to determine the prevalence of integrons among MDR Escherichia coli strains isolated from stool specimens and investigate the associations between the existence of integrons and MDR properties in the southwest of Iran. Methods There were 164 E. coli strains isolated from January 2012 to June 2012. Fecal specimens identified a...

  6. Detection of mcr-1 colistin resistance gene in polyclonal Escherichia coli isolates in Barcelona, Spain, 2012 to 2015.

    Science.gov (United States)

    Prim, Núria; Rivera, Alba; Rodríguez-Navarro, Judith; Español, Montserrat; Turbau, Miquel; Coll, Pere; Mirelis, Beatriz

    2016-03-31

    Colistin resistance was detected in 53 of 10,011 Escherichia coli (0.5%) by prospective phenotypic testing of consecutive clinical isolates in a single hospital in Barcelona, Spain (2012-15). The mcr-1 gene was retrospectively identified by PCR and sequencing in 15 of 50 available isolates. Each isolate had a unique PFGE pattern except for two. This clonal diversity supports the hypothesis of horizontal dissemination of the mcr-1 gene in the local study population. PMID:27055477

  7. Antimicrobial resistance, class 1 and 2 integrons and gene cassettes in avian Escherichia coli

    Directory of Open Access Journals (Sweden)

    Patrizia Robino

    2010-01-01

    Full Text Available Seventy-four Escherichia coli isolates were collected from domestic, synanthropic free living birds as well as wild and exotic birds, all living in captivity. Antimicrobial susceptibility was tested against a panel of 9 antibiotics, and presence of integrons (Class 1 and Class 2 and gene cassettes was analysed by PCR and sequencing, respectively. Twenty-eight isolates proved positive for Class 1 integrons and 19 for Class 2. Gene cassette arrangements were determined in 23 integron-positive isolates, which harboured one (aadA1 two (dfrA1-aadA1 or three (dfrA7-dfrA1-aadA1, dfrA1-sat1-aadA1 cassettes in their variable region. E. coli multiresistance to antimicrobials was observed in all groups examined, in particular domestic and synanthropic birds showed resistance to at least 4 antibiotics. A large number of isolates from domestic and synantropic birds proved to be Class 1 integron- positive, but unexpectedly, we observed many Class 2 integrons, usually considered less frequent.

  8. Bactericidal activity of Musca domestica cecropin (Mdc) on multidrug-resistant clinical isolate of Escherichia coli.

    Science.gov (United States)

    Lu, X; Shen, J; Jin, X; Ma, Y; Huang, Y; Mei, H; Chu, F; Zhu, J

    2012-08-01

    The housefly (Musca domestica) larvae have been used clinically to cure osteomyelitis, decubital necrosis, lip boil, ecthyma and malnutritional stagnation ever since the Ming/Qing Dynasty (1368 Anno Domini) till now, in China. In prior research, we have cloned and characterized a new gene of antimicrobial peptide cecropin from M. domestica larvae. This peptide was potently active against Gram-positive and Gram-negative bacteria standard strain. In the present study, we evaluated the possibility of Mdc to be a potential bactericidal agent against clinical isolates of multidrug-resistant (MDR) Escherichia coli and to elucidate the related antimicrobial mechanisms. Antimicrobial activity assays indicated a minimal inhibitory concentration (MIC) of 1.56 μM. Bactericidal kinetics at MIC showed that Mdc rapid killing of MDR E. coli. Lipopolysaccharide (LPS) dose-dependently suppressed Mdc antibacterial potency indicates that LPS is the initial binding site of Mdc in E. coli. Propidium iodide-based flow cytometry revealed that Mdc causes E. coli membrane permeabilization. Transmission electron micrographs further indicated that a remarkable damage in the bacteria's outer and inner membrane, even the leakage of cytoplasmic contents induced by Mdc. DNA binding experimental result implies that DNA is one of the possible intracellular targets of Mdc. Of note, Mdc did not show a perceptible cytotoxic effect on human red blood cells. Altogether, these results suggest that Mdc could be an excellent candidate for the development of more efficacious bactericidal agents. PMID:22202966

  9. Human intestinal cells modulate conjugational transfer of multidrug resistance plasmids between clinical Escherichia coli isolates.

    Directory of Open Access Journals (Sweden)

    Ana Manuel Dantas Machado

    Full Text Available Bacterial conjugation in the human gut microbiota is believed to play a major role in the dissemination of antibiotic resistance genes and virulence plasmids. However, the modulation of bacterial conjugation by the human host remains poorly understood and there is a need for controlled systems to study this process. We established an in vitro co-culture system to study the interaction between human intestinal cells and bacteria. We show that the conjugation efficiency of a plasmid encoding an extended spectrum beta-lactamase is reduced when clinical isolates of Escherichia coli are co-cultured with human intestinal cells. We show that filtered media from co-cultures contain a factor that reduces conjugation efficiency. Protease treatment of the filtered media eliminates this inhibition of conjugation. This data suggests that a peptide or protein based factor is secreted on the apical side of the intestinal cells exposed to bacteria leading to a two-fold reduction in conjugation efficiency. These results show that human gut epithelial cells can modulate bacterial conjugation and may have relevance to gene exchange in the gut.

  10. Environmental fluctuations do not select for increased variation or population-based resistance in Escherichia coli

    Indian Academy of Sciences (India)

    Shraddha Madhav Karve; Kanishka Tiwary; S Selveshwari; Sutirth Dey

    2016-03-01

    Little is known about the mechanisms that enable organisms to cope with unpredictable environments. To address this issue, we used replicate populations of Escherichia coli selected under complex, randomly changing environments. Under four novel stresses that had no known correlation with the selection environments, individual cells of the selected populations had significantly lower lag and greater yield compared to the controls. More importantly, there were no outliers in terms of growth, thus ruling out the evolution of population-based resistance. We also assayed the standing phenotypic variation of the selected populations, in terms of their growth on 94 different substrates. Contrary to expectations, there was no increase in the standing variation of the selected populations, nor was there any significant divergence from the ancestors. This suggested that the greater fitness in novel environments is brought about by selection at the level of the individuals, which restricts the suite of traits that can potentially evolve through this mechanism. Given that day-to-day climatic variability of the world is rising, these results have potential public health implications. Our results also underline the need for a very different kind of theoretical approach to study the effects of fluctuating environments.

  11. Antimicrobial Susceptibility and Molecular Mechanisms of Fosfomycin Resistance in Clinical Escherichia coli Isolates in Mainland China.

    Directory of Open Access Journals (Sweden)

    Ya Li

    Full Text Available Escherichia coli is one of the most common pathogens in nosocomial and community-acquired infections in humans. Fosfomycin is a broad-spectrum antibiotic which inhibits peptidoglycan synthesis responsible for bacterial cell wall formation. Although low, the exact E. coli susceptibility to fosfomycin as well as the mechanisms of resistance in the population from Mainland China are mostly unknown. 1109 non-duplicate clinical E. coli strains isolated from urine, sputum, blood and pus samples in 20 widely dispersed tertiary hospitals from Mainland China were collected from July 2009 to June 2010, followed by determination of minimum inhibitory concentrations of fosfomycin. Detection of the murA, glpT, uhpT, fosA, fosA3 and fosC genes was performed in fosfomycin non-susceptible E. coli strains and conjugation experiments were employed to determine the mobility of fosA3 gene. In this study, 7.8% (86/1109 E. coli strains were fosfomycin non-susceptible. Amino acid substitutions in GlpT and MurA were found in six and four E.coli strains, respectively, while the uhpT gene was absent in eighteen E.coli strains. Twenty-nine isolates carried the transferable plasmid with the fosA3 gene at high frequencies of around 10(-6 to 10(-7 per donor cell in broth mating. The majority of isolates were susceptible to fosfomycin, showing that the drug is still viable in clinical applications. Also, the main mechanism of E. coli resistance in Mainland China was found to be due to the presence of the fosA3 gene.

  12. Investigation of carbon storage regulation network (csr genes) and phenotypic differences between acid sensitive and resistant Escherichia coli O157:H7 strains

    Science.gov (United States)

    Background: Escherichia coli O157:H7 and related serotype strains have previously been shown to vary in acid resistance, however, little is known about strain specific mechanisms of acid resistance. We examined sensitive and resistant E. coli strains to determine the effects of growth in minimal and...

  13. SYNERGISTIC ANTIBACTERIAL EFFECTS OF THEAFLAVIN IN COMBINATION WITH AMPICILLIN AGAINST HOSPITAL ISOLATES OF STENOTROPHOMONAS MALTOPHILIA

    Directory of Open Access Journals (Sweden)

    Jonathan W. Betts

    2012-12-01

    Full Text Available Stenotrophomonas maltophilia is an important opportunistic nosocomial pathogen that shows intrinsic resistance to many antibiotics. This often limits treatment options and can cause lengthy hospital stays. Combination treatments are often used to combat resistance and using natural compounds such as polyphenols could give increased treatment options and even the reuse of antibiotics to which high levels of resistance have been observed. A checkerboard assay was used to determine if any synergy exists between ampicillin and the polyphenol theaflavin against 9 clinical isolates and one control isolate (NCTC 13014 of S. maltophilia. It was discovered that significant synergy (P  0.05 does exist between theaflavin and ampicillin, reducing the mean MIC of ampicillin from 12.5-22.9 µg/mL, in liquid culture, to 3.125-6.25 µg/mL. The FIC index was calculated to be 0.22-0.35 confirming synergy. From these results, significant potential for medical applications can be seen and further investigation is recommended.

  14. Antibiotic Resistance, RAPD- PCR Typing of Multiple Drug Resistant Strains of Escherichia Coli From Urinary Tract Infection (UTI)

    Science.gov (United States)

    Marialouis, Xavier Alexander

    2016-01-01

    Introduction Global spreading of multidrug resistant strains of Escherichia coli is responsible for Urinary Tract Infection (UTI) which is a major health problem in of concern. Among the gram negative bacteria, the major contributors for UTI belongs to the family Enterobacteriaceae, which includes E. coli, Klebsiella, Citrobacter and Proteus. However, E. coli accounts for the major cause of Urinary tract infections (UTIs) and accounts for 75% to 90% of UTI isolates. Aim The main aim of this study is to analyse the phylogenetic grouping of clinical isolates of UTI E. coli. Materials and Methods In this study nearly 58 E. coli strains were isolated and confirmed through microbiological, biochemical characterization. The urine samples were collected from outpatients having symptoms of UTI, irrespective of age and sex in Tamil Nadu, India. The isolates were subjected to analyse for ESBL and AmpC β-lactamase production. To understand its genetic correlation, molecular typing was carried out using RAPD-PCR method. Results Here we noted phenotypically twenty seven isolates were positive for ESBL and seven for AmpC β-lactamase production. However, among the ESBL isolates higher sensitivity was noted for Nitrofurantoin and Cefoxitin. It is worth to note that the prevalence of UTIs was more common among female and elderly male. Phylogenetic grouping revealed the presence of 24 isolates belonged to B2 group followed by 19 isolates to group A, eight isolates to group B1 and Seven isolates to group D. Conclusion Phenotypically most of the strains were positive for ESBL and showed high sensitivity for Nitrofurantoin and cefoxitin.

  15. Acid and base resistance in Escherichia coli and Shigella flexneri: role of rpoS and growth pH.

    OpenAIRE

    Small, P.; Blankenhorn, D; Welty, D; Zinser, E; Slonczewski, J L

    1994-01-01

    Escherichia coli K-12 strains and Shigella flexneri grown to stationary phase can survive several hours at pH 2 to 3, which is considerably lower than the acid limit for growth (about pH 4.5). A 1.3-kb fragment cloned from S. flexneri conferred acid resistance on acid-sensitive E. coli HB101; sequence data identified the fragment as a homolog of rpoS, the growth phase-dependent sigma factor sigma 38. The clone also conferred acid resistance on S. flexneri rpoS::Tn10 but not on Salmonella typh...

  16. In Vitro Antimicrobial Resistance of Urinary Escherichia coli Isolates among U.S. Outpatients from 2000 to 2010

    OpenAIRE

    Sanchez, Guillermo V.; Master, Ronald N; Karlowsky, James A.; Bordon, Jose M.

    2012-01-01

    This study examines in vitro antimicrobial resistance data from Escherichia coli isolates obtained from urine samples of U.S. outpatients between 2000 and 2010 using The Surveillance Network (TSN). Antimicrobial susceptibility results (n = 12,253,679) showed the greatest increases in E. coli resistance from 2000 to 2010 for ciprofloxacin (3% to 17.1%) and trimethoprim-sulfamethoxazole (TMP-SMX) (17.9% to 24.2%), whereas nitrofurantoin (0.8% to 1.6%) and ceftriaxone (0.2% to 2.3%) showed minim...

  17. Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this study,326 Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/cassettes.Minimum inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of E.coli has increased since the 1970s.The findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in China.

  18. Assessment of physicochemical parameters and prevalence of virulent and multiple-antibiotic-resistant Escherichia coli in treated effluent of two wastewater treatment plants and receiving aquatic milieu in Durban, South Africa.

    Science.gov (United States)

    Pillay, Leanne; Olaniran, Ademola O

    2016-05-01

    The poor operational status of some wastewater treatment plants often result in the discharge of inadequately treated effluent into receiving surface waters. This is of significant public health concern as there are many informal settlement dwellers (ISDs) that rely on these surface waters for their domestic use. This study investigated the treatment efficiency of two independent wastewater treatment plants (WWTPs) in Durban, South Africa and determined the impact of treated effluent discharge on the physicochemical and microbial quality of the receiving water bodies over a 6-month period. Presumptive Escherichia coli isolates were identified using biochemical tests and detection of the mdh gene via PCR. Six major virulence genes namely eae, hly, fliC, stx1, stx2, and rfbE were also detected via PCR while antibiotic resistance profiles of the isolates were determined using Kirby-Bauer disc diffusion assay. The physicochemical parameters of the wastewater samples ranged variously between 9 and 313.33 mg/L, 1.52 and 76.43 NTUs, and 6.30 and 7.87 for COD, turbidity, and pH respectively, while the E. coli counts ranged between 0 and 31.2 × 10(3) CFU/ml. Of the 200 selected E. coli isolates, the hly gene was found in 28 %, fliC in 20 %, stx2 in 17 %, eae in 14 %, with stx1 and rfbE in only 4 % of the isolates. Notable resistance was observed toward trimethoprim (97 %), tetracycline (56 %), and ampicillin (52.5 %). These results further highlight the poor operational status of these WWTPs and outline the need for improved water quality monitoring and enforcement of stringent guidelines. PMID:27037695

  19. Broilers as a source of quinolone-resistant and extraintestinal pathogenic Escherichia coli in the Czech Republic.

    Science.gov (United States)

    Literak, Ivan; Reitschmied, Tomas; Bujnakova, Dobroslava; Dolejska, Monika; Cizek, Alois; Bardon, Jan; Pokludova, Lucie; Alexa, Pavel; Halova, Dana; Jamborova, Ivana

    2013-02-01

    Extraintestinal Escherichia coli infections are associated with extraintestinal pathogenic E. coli (ExPEC) strains. A total of 114 E. coli isolates were characterized regarding their antimicrobial resistance in a prospective study of 319 broilers from 12 slaughterhouses in the Czech Republic, a European Union member, during 2008. PCR-based assays to define ExPEC-associated traits were performed in resistant strains. Consumption of antimicrobial drugs by poultry in the Czech Republic was also analyzed. Antibiotic resistance was detected in 82% of isolates. Resistance to nalidixic acid and ciprofloxacin was predominant. Plasmid-mediated quinolone resistance genes, qnrB19 and qnrS1, were detected in 1 and 3 of 93 resistant isolates, respectively. Twenty-three percent of resistant isolates were considered as ExPEC. In total, 972 kg of flumequine, enrofloxacin, and difloxacin were used in poultry in the Czech Republic during 2008. High prevalence of broilers with ciprofloxacin-resistant E. coli isolates was linked to consumption of quinolones in poultry. Broilers may comprise an important vehicle for community-wide dissemination of fluoroquinolone-resistant E. coli and ExPEC. Withdrawal of fluoroquinolones from use in chicken production should be seriously considered in the Czech Republic and the European Union as well. PMID:23020862

  20. Molecular characterization of quinolone resistance mechanisms and extended-spectrum β-lactamase production in Escherichia coli isolated from dogs.

    Science.gov (United States)

    Meireles, D; Leite-Martins, L; Bessa, L J; Cunha, S; Fernandes, R; de Matos, A; Manaia, C M; Martins da Costa, P

    2015-08-01

    The increasing prevalence of antimicrobial resistances is now a worldwide problem. Investigating the mechanisms by which pets harboring resistant strains may receive and/or transfer resistance determinants is essential to better understanding how owners and pets can interact safely. Here, we characterized the genetic determinants conferring resistance to β-lactams and quinolones in 38 multidrug-resistant Escherichia coli isolated from fecal samples of dogs, through PCR and sequencing. The most frequent genotype included the β-lactamase groups TEM (n=5), and both TEM+CTX-M-1 (n=5). Within the CTX-M group, we identified the genes CTX-M-32, CTX-M-1, CTX-M-15, CTX-M-55/79, CTX-M-14 and CTX-M-2/44. Thirty isolates resistant to ciprofloxacin presented two mutations in the gyrA gene and one or two mutations in the parC gene. A mutation in gyrA (reported here for the first time), due to a transversion and transition (TCG→GTG) originating a substitution of a serine by a valine in position 83 was also detected. The plasmid-encoded quinolone resistance gene, qnrs1, was detected in three isolates. Dogs can be a reservoir of genetic determinants conferring antimicrobial resistance and thus may play an important role in the spread of antimicrobial resistance to humans and other co-habitant animals. PMID:25999092

  1. Fluoroquinolone-resistance mechanisms and phylogenetic background of clinical Escherichia coli strains isolated in south-east Poland.

    Science.gov (United States)

    Korona-Glowniak, Izabela; Skrzypek, Kinga; Siwiec, Radosław; Wrobel, Andrzej; Malm, Anna

    2016-09-01

    Fluorochinolones are a class of broad-spectrum antimicrobials in the treatment of several infections, including those caused by Escherichia coli. Due to the increasing resistance of bacteria to antimicrobials, an understanding of fluoroquinolone resistance is important for infection control. The aim of this study was to determine susceptibility of clinical E. coli strains to fluoroquinolones and characterize their mechanisms of quinolone resistance. Totally, 79 non-duplicate clinical E. coli isolates included in this study were mainly from skin lesion -36 (45.6%) isolates; 54 (68.4%) isolates were assigned to phylogenetic B2 group. Resistance to ciprofloxacin was found in 20 isolates. In the quinolone resistance-determining region (QRDR) region of gyrA and parC, 4 types of point mutations were detected. Mutations in parC gene were found in all strains with gyrA mutations. Predominance of double mutation in codon 83 and 87 of gyrA (90%) and in codon 80 of parC (90%) was found. Moreover, plasmid-mediated quinolone resistance (PMRQ) determinants (qnrA or qnrB and/or aac(6')-Ib-cr) were present in 5 (25%) out of 20 fluoroquinolone-resistant isolates. Resistance to fluoroquinolones in all of the tested clinical E. coli isolates correlated with point mutations in both gyrA and parC. The majority of fluoroquinolone-resistant strains belonged to D and B2 phylogenetic groups. PMID:27602420

  2. Antimicrobial resistance markers of class 1 and class 2 integron-bearing Escherichia coli from irrigation water and sediments.

    Science.gov (United States)

    Roe, Matthew T; Vega, Everardo; Pillai, Suresh D

    2003-07-01

    Municipal and agricultural pollution affects the Rio Grande, a river that separates the United States from Mexico. Three hundred and twenty-two Escherichia coli isolates were examined for multiple antibiotic resistance phenotypes and the prevalence of class 1 and class 2 integron sequences. Thirty-two (10%) of the isolates were resistant to multiple antibiotics. Four (13%) of these isolates contained class 1-specific integron sequences; one isolate contained class 2 integron-specific sequences. Sequencing showed that the class 1 integron-bearing strain contained two distinct gene cassettes, sat-1 and aadA. Although three of the four class 1 integron-bearing strains harbored the aadA sequence, none of the strains was phenotypically resistant to streptomycin. These results suggest that integron-bearing E. coli strains can be present in contaminated irrigation canals and that these isolates may not express these resistance markers. PMID:12890322

  3. "Population structure of drug-susceptible,-resistant and ESBL-producing Escherichia coli from community-acquired urinary tract"

    DEFF Research Database (Denmark)

    Hertz, Frederik Boëtius; Nielsen, Jesper Boye; Schønning, Kristian; Littauer, Pia; Knudsen, Jenny Dahl; Løbner-Olesen, Anders; Frimodt-Møller, Niels

    2016-01-01

    BACKGROUND: Escherichia coli is the most common cause of urinary tract infection (UTI). The pathogenic isolates are becoming increasingly resistant to antibiotics; with a worldwide dissemination of resistant sequence types (ST). We characterized three different uropathogenic E. coli populations......, from non-hospitalized patients to describe the genetic kinship between resistant and susceptible isolates. We studied the populations by use of multi-locus sequence typing (MLST) and abbreviated-multi locus variable number of tandem repeat analysis (a-MLVA). Urine samples submitted for testing, by...... dominated vastly by ST131 (51 %), ST38 (9 %) and ST69 (6 %). In the resistant group ST69 (18 %), ST73 (11 %) and ST131 (15 %) were the largest clusters. In the susceptible population more STs and a-MLVA codes were identified compared to the other groups and ST73 and ST95 were found as the only clusters with...

  4. Ampicillin/penicillin-binding protein interactions as a model drug-target system to optimize affinity pull-down and mass spectrometric strategies for target and pathway identification.

    Science.gov (United States)

    von Rechenberg, Moritz; Blake, Brian Kelly; Ho, Yew-Seng J; Zhen, Yuejun; Chepanoske, Cindy Lou; Richardson, Bonnie E; Xu, Nafei; Kery, Vladimir

    2005-05-01

    The identification and validation of the targets of active compounds identified in cell-based assays is an important step in preclinical drug development. New analytical approaches that combine drug affinity pull-down assays with mass spectrometry (MS) could lead to the identification of new targets and druggable pathways. In this work, we investigate a drug-target system consisting of ampicillin- and penicillin-binding proteins (PBPs) to evaluate and compare different amino-reactive resins for the immobilization of the affinity compound and mass spectrometric methods to identify proteins from drug affinity pull-down assays. First, ampicillin was immobilized onto various amino-reactive resins, which were compared in the ampicillin-PBP model with respect to their nonspecific binding of proteins from an Escherichia coli membrane extract. Dynal M-270 magnetic beads were chosen to further study the system as a model for capturing and identifying the targets of ampicillin, PBPs that were specifically and covalently bound to the immobilized ampicillin. The PBPs were identified, after in situ digestion of proteins bound to ampicillin directly on the beads, by using either one-dimensional (1-D) or two-dimensional (2-D) liquid chromatography (LC) separation techniques followed by tandem mass spectrometry (MS/MS) analysis. Alternatively, an elution with N-lauroylsarcosine (sarcosyl) from the ampicillin beads followed by in situ digestion and 2-D LC-MS/MS analysis identified proteins potentially interacting noncovalently with the PBPs or the ampicillin. The in situ approach required only little time, resources, and sample for the analysis. The combination of drug affinity pull-down assays with in situ digestion and 2-D LC-MS/MS analysis is a useful tool in obtaining complex information about a primary drug target as well as its protein interactors. PMID:15761956

  5. Comparative Analysis of Quinolone Resistance in Clinical Isolates of Klebsiella pneumoniae and Escherichia coli from Chinese Children and Adults

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2015-01-01

    Full Text Available The objective of this study was to compare quinolone resistance and gyrA mutations in clinical isolates of Klebsiella pneumoniae and Escherichia coli from Chinese adults who used quinolone in the preceding month and children without any known history of quinolone administration. The antimicrobial susceptibilities of 61 isolates from children and 79 isolates from adults were determined. The mutations in the quinolone resistance-determining regions in gyrA gene were detected by PCR and DNA sequencing. Fluoroquinolone resistance and types of gyrA mutations in isolates from children and adults were compared and statistically analyzed. No significant differences were detected in the resistance rates of ciprofloxacin and levofloxacin between children and adults among isolates of the two species (all P>0.05. The double mutation Ser83→Leu + Asp87→Asn in the ciprofloxacin-resistant isolates occurred in 73.7% isolates from the children and 67.9% from the adults, respectively (P=0.5444. Children with no known history of quinolone administration were found to carry fluoroquinolone-resistant Enterobacteriaceae isolates. The occurrence of ciprofloxacin resistance and the major types of gyrA mutations in the isolates from the children were similar to those from adults. The results indicate that precautions should be taken on environmental issues resulting from widespread transmission of quinolone resistance.

  6. Computational Analysis of Pharmacokinetic Behavior of Ampicillin

    Directory of Open Access Journals (Sweden)

    Mária Ďurišová

    2016-07-01

    Full Text Available orrespondence: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, 841 04 Bratislava, Slovak Republic. Phone + 42-1254775928; Fax +421254775928; E-mail: maria.durisova@savba.sk 84 RESEARCH ARTICLE The objective of this study was to perform a computational analysis of the pharmacokinetic behavior of ampicillin, using data from the literature. A method based on the theory of dynamic systems was used for modeling purposes. The method used has been introduced to pharmacokinetics with the aim to contribute to the knowledge base in pharmacokinetics by including the modeling method which enables researchers to develop mathematical models of various pharmacokinetic processes in an identical way, using identical model structures. A few examples of a successful use of the modeling method considered here in pharmacokinetics can be found in full texts articles available free of charge at the website of the author, and in the example given in the this study. The modeling method employed in this study can be used to develop a mathematical model of the pharmacokinetic behavior of any drug, under the condition that the pharmacokinetic behavior of the drug under study can be at least partially approximated using linear models.

  7. Frequency and Antimicrobial Resistance Pattern of Extended Spectrum Beta Lactamases Producing Escherichia coli Strains Isolated from Urinary Infections

    Directory of Open Access Journals (Sweden)

    Mohammad Rasoul Tohidnia

    2013-07-01

    Full Text Available AbstractBackground and objectives: Escherichia coli is the most common cause of urinary tract infections. The resistance of Escherichia coli strains to broad spectrum cephalosporins may be mediated by extended spectrum β-lactamases (ESBLs has now raised in worldwide. Frequency and spectrum awareness of drug resistance in these isolates will be useful in choosing more effective methods of control and treatment. Materials and methods: This cross - sectional study was done on 100 Uropathogenic E. coli strains collected from selected center and then were identified by biochemical tests. All of the samples were screened by DAD method. The phenotypes of ESBL were determined using the disk diffusion synergy test(DDST as recommended by the interpretative guidelines of the NCCLS. SPSS16 was used for statistical analysis. Results: A total of one hundred isolates,89(89%were found to be resistant at least on of the indicators cephalosporin tested according to NCCLS guideline.55(55%of the isolates were resistant to all the indicators tested. Sixty tree isolates (63% were ESBL producers. The E. coli strains showed high susceptibility to imipenem (66/7%and amikacin (65/1%.Conclusion: Our results show that the most appropriate antibiotic to be used for empirical therapy are imipenem and amikacin.High prevalence of ESBL in our hospital cannot be ignored. ESBL producers can be detected by DDST and phenotypic confirmatory test with equal efficacy.we recommend DDSTusing multiple antibiotics in all microbiology units as a routine screening test.

  8. Antimicrobial Resistance in Generic Escherichia coli Isolates from Wild Small Mammals Living in Swine Farm, Residential, Landfill, and Natural Environments in Southern Ontario, Canada▿

    OpenAIRE

    Allen, Samantha E.; Boerlin, Patrick; Janecko, Nicol; Lumsden, John S; Barker, Ian K; Pearl, David L; Reid-Smith, Richard J.; Jardine, Claire

    2010-01-01

    To assess the impacts of different types of human activity on the development of resistant bacteria in the feces of wild small mammals, we compared the prevalences and patterns of antimicrobial resistance and resistance genes in generic Escherichia coli and Salmonella enterica isolates from fecal samples collected from wild small mammals living in four environments: swine farms, residential areas, landfills, and natural habitats. Resistance to antimicrobials was observed in E. coli isolates f...

  9. Antibiotic resistance in children with complicated urinary tract infection

    International Nuclear Information System (INIS)

    Objective was to determine the resistance of antibiotics for complicated urinary tract infection (UTI), including urinary tract anomaly (UTA), for empirical antibiotic therapy of complicated UTI. Four hundred and twenty two urine isolates were obtained from 113 patients with recurrent UTI, who used prophylactic antibiotics between February 1999 and November 2004 in the Eskisehir Osmangazi University, Eskisehir, Turkey. Reflux was found to be most important predisposing factor for recurrent UTI (31.9%). Renal scar was detected more in patients with UTA than without UTA (59.2% versus 12.4%, p<0.05). Gram-negative organisms were dominant in patients with and without UTA (91.5% and 79.2%). Enterococci and Candida spp. were more prevalent in children with UTA than without UTA (p<0.001). Isolates were significantly more resistant to ampicillin, trimethoprim-sulfamethoxazole, amikacin, co-amoxiclav, ticarcillin-clvalanate and piperacillin-tazobactam in patients with UTA than without UTA. We found low resistance to ciprofloxacin and nitrofurantoin in UTI with and without UTA. Enterococci spp. was highly resistance to ampicillin and amikacin in patients with UTA. Aztreonam, meropenem and ciprofloxacin seemed to be the best choice for treatment of UTI with UTA due to Escherichia coli and Klebsiella spp. Nitrofurantoin and nalidixic acid may be first choice antibiotics for prophylaxis in UTI with and without UTA. The UTI with UTA caused by Enterococci spp. might not benefit from a combination of amikacin and ampicillin, it could be treated with glycopeptides. (author)

  10. Investigation on Antimicrobial Drug Resistance to Escherichia coli Isolates from A Farm in Tacheng Xinj iang%新疆塔城某规模化养殖场大肠埃希菌耐药性调查

    Institute of Scientific and Technical Information of China (English)

    南海辰; 夏利宁; 刘英玉; 翟少华; 底丽娜

    2014-01-01

    为了解新疆塔城某规模化养殖场分离的大肠埃希菌对临床常用抗菌药物的耐药情况,从该规模化养殖场中采集的水样、饲料样、牛粪样及羊粪样中分离大肠埃希菌。采用微量肉汤法检测其对抗菌药物的耐药情况。结果表明,采集牛源饮用水样35份,分离率100.0%(35/35),分离的大肠埃希菌仅对阿莫西林/克拉维酸(31.4%)和氨苄西林(20.0%)2种抗菌药物耐药;牛源饲料样15份,分离率86.7%(13/15),分离的大肠埃希菌对氨苄西林(30.8%)、阿莫西林/克拉维酸(23.1%)、安普霉素(15.4%)、诺氟沙星(7.7%)、恩诺沙星(7.7%)和庆大霉素(7.7%)6种抗菌药物耐药;牛粪样20份,分离率100.0%(20/20),分离的大肠埃希菌对氨苄西林(60.0%)、阿莫西林/克拉维酸(50.0%)、恩诺沙星(40.0%)、庆大霉素(40.0%)、头孢噻呋(35.0%)、阿米卡星(25.0%)、诺氟沙星(10.0%)和环丙沙星(10.0%)8种抗菌药物耐药;羊粪样55份,分离率100.0%(55/55),分离的大肠埃希菌对阿莫西林/克拉维酸(25.5%)、氨苄西林(12.7%)、庆大霉素(5.5%)、头孢噻呋(3.6%)、诺氟沙星(1.8%)、恩诺沙星(1.8%)和阿米卡星(1.8%)7种抗菌药物耐药。新疆塔城牛源大肠埃希菌对常用抗菌药物多药耐药情况较严重,临床用药需谨慎,且可能存在粪源菌污染水源和饲料的风险。%In order to investigate commonly used antimicrobial drug resistance to Escherichia coli isolates from a farm in Tacheng,Xinj iang,the minimal inhibitory concentrations (MIC)of the antimicrobial drugs to these isolates from drinking water,feed,bovine feces and ovine feces were determined by the broth mi-cro-dilution method.The results showed that:3 5 E.coli isolates were confirmed

  11. Fluorescent ampicillin analogues as multifunctional disguising agents against opsonization.

    Science.gov (United States)

    Kotagiri, Nalinikanth; Sakon, Joshua; Han, Haewook; Zharov, Vladimir P; Kim, Jin-Woo

    2016-07-01

    Cancer nanomedicines are opening new paradigms in cancer management and recent research points to how they can vastly improve imaging and therapy through multimodality and multifunctionality. However, challenges to achieving optimal efficacy are manifold starting from processing materials and evaluating their intended effectiveness on biological tissue, to developing new strategies aimed at improving transport of these materials through the biological milieu to the target tissue. Here, we report a fluorescent derivative of a beta-lactam antibiotic, ampicillin (termed iAmp) and its multifunctional physicobiochemical characteristics and potential as a biocompatible shielding agent and an effective dispersant. Carbon nanotubes (CNTs) were chosen to demonstrate the efficacy of iAmp. CNTs are known for their versatility and have been used extensively for cancer theranostics as photothermal and photoacoustic agents, but have limited solubility in water and biocompatibility. Traditional dispersants are associated with imaging artifacts and are not fully biocompatible. The chemical structure of iAmp is consistent with a deamination product of ampicillin. Although the four-membered lactam ring is intact, it does not retain the antibiotic properties. The iAmp is an effective dispersant and simultaneously serves as a fluorescent label for single-walled CNTs (SWNTs) with minimal photobleaching. The iAmp also enables bioconjugation of SWNTs to bio-ligands such as antibodies through functional carboxyl groups. Viability tests show that iAmp-coated SWNTs have minimal toxicity. Bio-stability tests under physiological conditions reveal that iAmp coating not only remains stable in a biologically relevant environment with high protein and salt concentrations, but also renders SWNTs transparent against nonspecific protein adsorption, also known as protein corona. Mammalian tissue culture studies with macrophages and opsonins validate that iAmp coating affords immunological resistance

  12. Nickel and cobalt resistance engineered in Escherichia coli by overexpression of serine acetyltransferase from the nickel hyperaccumulator plant Thlaspi goesingense.

    Science.gov (United States)

    Freeman, John L; Persans, Michael W; Nieman, Ken; Salt, David E

    2005-12-01

    The overexpression of serine acetyltransferase from the Ni-hyperaccumulating plant Thlaspi goesingense causes enhanced nickel and cobalt resistance in Escherichia coli. Furthermore, overexpression of T. goesingense serine acetyltransferase results in enhanced sensitivity to cadmium and has no significant effect on resistance to zinc. Enhanced nickel resistance is directly related to the constitutive overactivation of sulfur assimilation and glutathione biosynthesis, driven by the overproduction of O-acetyl-L-serine, the product of serine acetyltransferase and a positive regulator of the cysteine regulon. Nickel in the serine acetyltransferase-overexpressing strains is not detoxified by coordination or precipitation with sulfur, suggesting that glutathione is involved in reducing the oxidative damage imposed by nickel. PMID:16332856

  13. "Population structure of drug-susceptible,-resistant and ESBL-producing Escherichia coli from community-acquired urinary tract"

    DEFF Research Database (Denmark)

    Hertz, Frederik Boëtius; Nielsen, Jesper Boye; Schønning, Kristian;

    2016-01-01

    with 16 % and 6 %, respectively. Ninety-eight per cent of the ESBL-producing E. coli isolates were CTX-M-producers. CONCLUSION: ST131 dominated the population of community-associated uropathogenic ESBL-producing E. coli, but was less frequent among non-ESBL-producing E. coli. The fully susceptible E. coli......BACKGROUND: Escherichia coli is the most common cause of urinary tract infection (UTI). The pathogenic isolates are becoming increasingly resistant to antibiotics; with a worldwide dissemination of resistant sequence types (ST). We characterized three different uropathogenic E. coli populations......, from non-hospitalized patients to describe the genetic kinship between resistant and susceptible isolates. We studied the populations by use of multi-locus sequence typing (MLST) and abbreviated-multi locus variable number of tandem repeat analysis (a-MLVA). Urine samples submitted for testing...

  14. The effects of ampicillin oral contraceptive steroids in women.

    OpenAIRE

    Back, D J; Breckenridge, A. M.; Maciver, M; Orme, M; Rowe, P H; Staiger, C; Thomas, E.; J. Tjia

    1982-01-01

    1 Thirteen women taking long term oral contraceptive steroids were studied while taking ampicillin (500 mg three times daily) and compared to a control cycle while not taking ampicillin. 2 There were no significant changes in the plasma concentrations of ethinyloestradiol, levonorgestrel, follicle stimulating hormone or progesterone, although lower concentrations of ethinyloestradiol were noted in two women. 3 We conclude that most patients taking oral contraceptive steroids do not need to ta...

  15. The changing pattern of antimicrobial resistance within 42,033 Escherichia coli isolates from nosocomial, community and urology patient-specific urinary tract infections, Dublin, 1999-2009.

    LENUS (Irish Health Repository)

    Cullen, Ivor M

    2012-04-01

    To investigate the changing pattern of antimicrobial resistance in Escherichia coli urinary tract infection over an eleven year period, and to determine whether E. coli antibiotic resistance rates vary depending on whether the UTI represents a nosocomial, community acquired or urology patient specific infection.

  16. Use of the D-R model to define trends in the emergence of Ceftazidime-resistant Escherichia coli in China

    Science.gov (United States)

    Objective: To assess the efficacy of the D-R model for defining trends in the appearance of Ceftazidime-resistant Escherichia coli. Methods: Actual data related to the manifestation of Ceftazidime-resistant E.coli spanning years 1996-2009 were collected from the China National Knowledge Internet (CN...

  17. Fluoroquinolone resistance and molecular characterization of gyrA and parC quinolone resistance-determining regions in Escherichia coli isolated from poultry.

    Science.gov (United States)

    Vanni, M; Meucci, V; Tognetti, R; Cagnardi, P; Montesissa, C; Piccirillo, A; Rossi, A M; Di Bello, D; Intorre, L

    2014-04-01

    Escherichia coli are a common inhabitant of the gastrointestinal tract of mammals and birds; nevertheless, they may be associated with a variety of severe and invasive infections. Whereas fluoroquinolones (FQ) have been banned in the United States for use in poultry production, the use of these antimicrobials in poultry husbandry is still possible in the European Union, although with some restrictions. The aim of this study was to investigate the FQ resistance of 235 E. coli isolates recovered from chickens and turkeys. Minimum inhibitory concentrations were determined by a microdilution method, whereas mutations in the quinolone resistance-determining regions of the target genes, gyrA and parC, were detected by a PCR-based method. High resistance rates (>60%) were observed for nalidixic acid, flumequine, and difloxacin, whereas resistance to ciprofloxacin, danofloxacin, enrofloxacin, marbofloxacin, and sarafloxacin was less frequently reported (difloxacin, danofloxacin, and sarafloxacin had in addition 1 or 2 parC substitutions. Two gyrA mutations coupled with 1 substitution in parC were detected in isolates resistant to all tested FQ. The number of mutations and their correlation with the in vitro activity of FQ reflected the currently accepted model, according to which a single gyrA substitution is associated with resistance or decreased susceptibility to older quinolones, whereas further gyrA or parC substitutions are needed for a higher level of resistance. PMID:24706962

  18. A randomized, prospective study of adjunctive Ampicillin in preterm labor

    Directory of Open Access Journals (Sweden)

    Tehranian A

    1999-09-01

    Full Text Available Acute amniotic fluid infection has emerged as a possible cause of many heretofore unexplained preterm births. Our purpose was to determine the effect of ampicillin in the prolongation of pregnancies receiving tocolysis for preterm labor. A blinded, placebo-controlled, randomized trial was conducted to study ampicillin in women hospitalized for preterm labor between 24 and 37 weeks' gestation. A total of 60 patients with intact membranes and without chorioamnionitis who were receiving magnesium sulfate were screened. Thirty women with preterm labor received ampicillin, and 30 received placebos. The primary end point was prolongation of gestation. There was no difference in age of delivery (37.6±9.7 days vs 36.08±3.9 days, P=0.085 and no difference in retardation of delivery (4.7±3.1 vs 4.1±2.1, P=0.39. The mean degree of preterm delivery were 0.62±1.93 and 1.8±3.3 weeks in ampicillin and placebo groups, respectively (not significant, P>0.1. Conclusions: Ampicillin had no effect on interval to delivery or duration of pregnancy in women treated for preterm labor. So rotine clinical use of ampicillin during tocolysis should not be recommended.

  19. Antimalarial therapy selection for quinolone resistance among Escherichia coli in the absence of quinolone exposure, in tropical South America.

    Directory of Open Access Journals (Sweden)

    Ross J Davidson

    Full Text Available BACKGROUND: Bacterial resistance to antibiotics is thought to develop only in the presence of antibiotic pressure. Here we show evidence to suggest that fluoroquinolone resistance in Escherichia coli has developed in the absence of fluoroquinolone use. METHODS: Over 4 years, outreach clinic attendees in one moderately remote and five very remote villages in rural Guyana were surveyed for the presence of rectal carriage of ciprofloxacin-resistant gram-negative bacilli (GNB. Drinking water was tested for the presence of resistant GNB by culture, and the presence of antibacterial agents and chloroquine by HPLC. The development of ciprofloxacin resistance in E. coli was examined after serial exposure to chloroquine. Patient and laboratory isolates of E. coli resistant to ciprofloxacin were assessed by PCR-sequencing for quinolone-resistance-determining-region (QRDR mutations. RESULTS: In the very remote villages, 4.8% of patients carried ciprofloxacin-resistant E. coli with QRDR mutations despite no local availability of quinolones. However, there had been extensive local use of chloroquine, with higher prevalence of resistance seen in the villages shortly after a Plasmodium vivax epidemic (p<0.01. Antibacterial agents were not found in the drinking water, but chloroquine was demonstrated to be present. Chloroquine was found to inhibit the growth of E. coli in vitro. Replica plating demonstrated that 2-step QRDR mutations could be induced in E. coli in response to chloroquine. CONCLUSIONS: In these remote communities, the heavy use of chloroquine to treat malaria likely selected for ciprofloxacin resistance in E. coli. This may be an important public health problem in malarious areas.

  20. A response regulator from a soil metagenome enhances resistance to the β-lactam antibiotic carbenicillin in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Heather K Allen

    Full Text Available Functional metagenomic analysis of soil metagenomes is a method for uncovering as-yet unidentified mechanisms for antibiotic resistance. Here we report an unconventional mode by which a response regulator derived from a soil metagenome confers resistance to the β-lactam antibiotic carbenicillin in Escherichia coli. A recombinant clone (βlr16 harboring a 5,169 bp DNA insert was selected from a metagenomic library previously constructed from a remote Alaskan soil. The βlr16 clone conferred specific resistance to carbenicillin, with limited increases in resistance to other tested antibiotics, including other β-lactams (penicillins and cephalosporins, rifampin, ciprofloxacin, erythromycin, chloramphenicol, nalidixic acid, fusidic acid, and gentamicin. Resistance was more pronounced at 24°C than at 37°C. Zone-of-inhibition assays suggested that the mechanism of carbenicillin resistance was not due to antibiotic inactivation. The DNA insert did not encode any genes known to confer antibiotic resistance, but did have two putative open reading frames (ORFs that were annotated as a metallopeptidase and a two-component response regulator. Transposon mutagenesis and subcloning of the two ORFs followed by phenotypic assays showed that the response regulator gene was necessary and sufficient to confer the resistance phenotype. Quantitative reverse transcriptase PCR showed that the response regulator suppressed expression of the ompF porin gene, independently of the small RNA regulator micF, and enhanced expression of the acrD, mdtA, and mdtB efflux pump genes. This work demonstrates that antibiotic resistance can be achieved by the modulation of gene regulation by heterologous DNA. Functional analyses such as these can be important for making discoveries in antibiotic resistance gene biology and ecology.

  1. Novel gyrA point mutation in a strain of Escherichia coli resistant to fluoroquinolones but not to nalidixic acid.

    OpenAIRE

    Cambau, E.; Bordon, F; Collatz, E; Gutmann, L

    1993-01-01

    We have previously described a clinical isolate of Escherichia coli (Q2) that is highly resistant to fluoroquinolones (MIC of ciprofloxacin, 16 micrograms/ml) but susceptible to nalidixic acid (MIC of nalidixic acid, 4 micrograms/ml) (N. Moniot-Ville, J. Guibert, N. Moreau, J.F. Acar, E. Collatz, and L. Gutmann, Antimicrob. Agents Chemother. 35:519-523, 1991). Transformation of strain Q2 with a plasmid carrying the wild-type gyrA gene from E. coli K-12(pAFF801) resulted in a 32-fold decrease ...

  2. A mutation in the 530 loop of Escherichia coli 16S ribosomal RNA causes resistance to streptomycin.

    OpenAIRE

    Melançon, P; Lemieux, C; Brakier-Gingras, L

    1988-01-01

    Oligonucleotide-directed mutagenesis was used to introduce an A to C transversion at position 523 in the 16S ribosomal RNA gene of Escherichia coli rrnB operon cloned in plasmid pKK3535. E. coli cells transformed with the mutated plasmid were resistant to streptomycin. The mutated ribosomes isolated from these cells were not stimulated by streptomycin to misread the message in a poly(U)-directed assay. They were also restrictive to the stimulation of misreading by other error-promoting relate...

  3. Investigation of Biofield Treatment on Antimicrobial Susceptibility, Biochemical Reaction Pattern and Biotyping of Enteropathogenic Multidrug-Resistant Escherichia coli Isolates

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Study background: Multidrug resistant Escherichia coli (MDR E. coli) has become a major health concern, and failure of treatment leads to huge health burden. Aim of the present study was to determine the impact of Mr. Trivedi’s biofield treatment on E. coli. Methods: Four MDR clinical lab isolates (LSs) of E. coli (LS 8, LS 9, LS 10, and LS 11) were taken and divided into two groups i.e. control and biofield treated. Control and treated samples were identified with respect...

  4. Comparison of the Transport of Tetracycline-Resistant and Tetracycline-Susceptible Escherichia coli Isolated from Lake Michigan

    OpenAIRE

    Walczak, Jacob J.; Bardy, Sonia L.; Feriancikova, Lucia; Xu, Shangping

    2011-01-01

    It was recently reported that tetracycline could enhance the mobility of manure-derived Escherichia coli within saturated porous media (Walczak et al. (Water Research 45:1681–1690, 2011)). It was also shown, however, that E. coli from various sources could display marked variation in their mobility (Bolster et al. (Journal of Environmental Quality 35:1018–1025, 2009)). The focus of this research was to examine if the observed difference in the mobility of manure-derived tetracycline-resistant...

  5. Antimicrobial susceptibility patterns of clinical Escherichia coli isolates from dogs and cats in the United States: January 2008 through January 2013.

    Science.gov (United States)

    Thungrat, Kamoltip; Price, Stuart B; Carpenter, D Mark; Boothe, Dawn Merton

    2015-09-30

    Escherichia coli is among the most common bacterial pathogens in dogs and cats. The lack of a national monitoring program limits evidence-based empirical antimicrobial choices in the United States. This study describes antimicrobial susceptibility patterns for presumed clinical E. coli isolates from dogs (n=2392) or cats (n=780) collected from six geographic regions in the United States between May 2008 and January 2013. Minimum inhibitory concentrations (MIC) were determined for 17 drugs representing 6 drug classes. Urinary tract isolates were most common (71%). Population MIC distributions were generally bimodal with the second mode above the resistant breakpoint for all drugs except gentamicin, amikacin, and meropenem. The MIC90 exceeded the susceptible breakpoint for ampicillin, amoxicillin-clavulanic acid, cephalothin (surrogate drug for cephalexin), and doxycycline but was below the susceptible breakpoint for all others. None of isolates was susceptible or resistant to all drug tested; 46% were resistant to 1 or 2 antimicrobial categories, and 52% to more than three categories. The resistance percentages were as follows: doxycycline (100%), cephalothin (98%)>ampicillin (48%)>amoxicillin-clavulanic acid (40%)>ticarcillin-clavulanic acid (18%)>cefpodoxime (13%), cefotaxime (12%), cefoxitin (11%), cefazolin (11%), enrofloxacin (10%), chloramphenicol (9.6%)>ciprofloxacin (9.2%), ceftazidime (8.7%), trimethoprim-sulfamethoxazole (7.9%), gentamicin (7.9%)>meropenem (1.5%), amikacin (0.7%) (P<0.05). Resistance to ampicillin and amoxicillin-clavulanic acid was greatest in the South-Central region (P<0.05). E. coli resistance may preclude empirical treatment with doxycycline, cephalexin, ampicillin, or amoxicillin-clavulanic acid. Based on susceptibility patterns, trimethoprim-sulfonamides may be the preferred empirical oral treatment. PMID:26165272

  6. A simplified kinetic model for the side reactions occurring during the enzymatic synthesis of ampicillin

    Directory of Open Access Journals (Sweden)

    A.L.O. Ferreira

    2000-12-01

    Full Text Available This work presents a kinetic study of the side reactions of the ampicillin enzymatic synthesis, from phenylglycine methyl ester and 6-aminopenicillanic acid using penicillin G acylase immobilized on agarose. A Michaelis-Menten model with competitive inhibition was fitted to initial rates of ester and antibiotic hydrolysis, at pH 6.5 and 25ºC. Inherent kinetic parameters were estimated for low enzymatic loads, to assure that diffusional resistance was not important. It was observed that ampicillin inhibits the hydrolysis of PGME, but the inhibitory effect of the ester on ampicillin hydrolysis was almost negligible. The obtained parameters were: k cat1= 0.025 mM/UI min, Km1 = 155.4mM, K AE = 16.18mM, k cat2= 4.67x10-3 mM/UI min, Km2 = 11.47, K EA = 0.68 mM. Parameter values are in the range reported in the literature, except for Km1, which is much higher. The large confidence interval for this parameter denotes that the model presents low sensitivity with respect to it.

  7. Fluorescent ampicillin analogues as multifunctional disguising agents against opsonization

    Science.gov (United States)

    Kotagiri, Nalinikanth; Sakon, Joshua; Han, Haewook; Zharov, Vladimir P.; Kim, Jin-Woo

    2016-06-01

    Cancer nanomedicines are opening new paradigms in cancer management and recent research points to how they can vastly improve imaging and therapy through multimodality and multifunctionality. However, challenges to achieving optimal efficacy are manifold starting from processing materials and evaluating their intended effectiveness on biological tissue, to developing new strategies aimed at improving transport of these materials through the biological milieu to the target tissue. Here, we report a fluorescent derivative of a beta-lactam antibiotic, ampicillin (termed iAmp) and its multifunctional physicobiochemical characteristics and potential as a biocompatible shielding agent and an effective dispersant. Carbon nanotubes (CNTs) were chosen to demonstrate the efficacy of iAmp. CNTs are known for their versatility and have been used extensively for cancer theranostics as photothermal and photoacoustic agents, but have limited solubility in water and biocompatibility. Traditional dispersants are associated with imaging artifacts and are not fully biocompatible. The chemical structure of iAmp is consistent with a deamination product of ampicillin. Although the four-membered lactam ring is intact, it does not retain the antibiotic properties. The iAmp is an effective dispersant and simultaneously serves as a fluorescent label for single-walled CNTs (SWNTs) with minimal photobleaching. The iAmp also enables bioconjugation of SWNTs to bio-ligands such as antibodies through functional carboxyl groups. Viability tests show that iAmp-coated SWNTs have minimal toxicity. Bio-stability tests under physiological conditions reveal that iAmp coating not only remains stable in a biologically relevant environment with high protein and salt concentrations, but also renders SWNTs transparent against nonspecific protein adsorption, also known as protein corona. Mammalian tissue culture studies with macrophages and opsonins validate that iAmp coating affords immunological resistance

  8. Variation in Resistance Traits, Phylogenetic Backgrounds, and Virulence Genotypes among Escherichia coli Clinical Isolates from Adjacent Hospital Campuses Serving Distinct Patient Populations

    OpenAIRE

    Drawz, Sarah M.; Porter, Stephen; Kuskowski, Michael A.; Johnston, Brian; Clabots, Connie; Kline, Susan; FERRIERI, PATRICIA; Johnson, James R.

    2015-01-01

    Escherichia coli sequence type 13 (ST131), an emergent cause of multidrug-resistant extraintestinal infections, has important phylogenetic subsets, notably the H30 and H30Rx subclones, with distinctive resistance profiles and, possibly, clinical associations. To clarify the local prevalence of these ST131 subclones and their associations with antimicrobial resistance, ecological source, and virulence traits, we extensively characterized 233 consecutive E. coli clinical isolates (July and Augu...

  9. Genotyping DNA chip for the simultaneous assessment of antibiotic resistance and pathogenic potential of extraintestinal pathogenic Escherichia coli.

    Science.gov (United States)

    Barl, Timo; Dobrindt, Ulrich; Yu, Xiaolei; Katcoff, Don J; Sompolinsky, David; Bonacorsi, Stéphane; Hacker, Jörg; Bachmann, Till T

    2008-09-01

    Urinary tract infections (UTIs) are among the most frequently occurring infections and are mostly caused by extraintestinal pathogenic Escherichia coli. DNA microarrays are potent molecular diagnostic tools for rapid diagnosis of bacterial infections with high relevance for UTIs. In this study, we present the integration and application of two DNA chip modules for the simultaneous detection of single nucleotide polymorphisms in gyrA (quinolone resistance) and fimH (increased adhesion to urinary tract epithelium). The performance of the combined diagnostic chip was assessed by genotyping 140 E. coli strains. Resistance-causing mutations could only be identified in UTI isolates. A complete genotyping assay could be performed in tool for routine clinical diagnostics. PMID:18640014

  10. Escherichia coli ASKA Clone Library Harboring tRNA-Specific Adenosine Deaminase (tadA Reveals Resistance towards Xanthorrhizol

    Directory of Open Access Journals (Sweden)

    Yogiara

    2015-09-01

    Full Text Available Xanthorrhizol is a potent antimicrobial compound isolated from the rhizome of Curcuma xanthorrhiza. However, the mechanism of xanthorrhizol action is unknown. To screen for probable target(s, we introduced the ASKA pooled-plasmid library into Escherichia coli W3110 imp4213 and enriched the library for resistant clones with increasing concentrations of xanthorrhizol. After three rounds of enrichment, we found nine genes that increased xanthorrhizol resistance. The resistant clones were able to grow in LB medium containing 256 µg/mL xanthorrhizol, representing a 16-fold increase in the minimum inhibitory concentration. Subsequent DNA sequence analysis revealed that overexpression of tadA, galU, fucU, ydeA, ydaC, soxS, nrdH, yiiD, and mltF genes conferred increased resistance towards xanthorrhizol. Among these nine genes, tadA is the only essential gene. tadA encodes a tRNA-specific adenosine deaminase. Overexpression of E. coli W3110 imp4213 (pCA24N-tadA conferred resistance to xanthorrhizol up to 128 µg/mL. Moreover, overexpression of two tadA mutant enzymes (A143V and F149G led to a twofold increase in the MIC. These results suggest that the targets of xanthorrhizol may include tadA, which has never before been explored as an antibiotic target.

  11. Library sequencing strategies for comparative analysis of stress resistance mechanisms in Escherichia coli strains

    DEFF Research Database (Denmark)

    Lennen, Rebecca; Bonde, Ida; Koza, Anna;

    2014-01-01

    exploited Tn-Seq to probe the basis for the large variations in osmotic and acetate stress tolerance of different laboratory strains of Escherichia coli (K-12 MG1655, BL21(DE3), W, and Crooks). Little is currently known to explain the source of this variation and to enable rational engineering to impart...

  12. CTX-M Expression and Selection of Ertapenem Resistance in Klebsiella pneumoniae and Escherichia coli▿

    OpenAIRE

    Girlich, Delphine; Poirel, Laurent; Nordmann, Patrice

    2008-01-01

    In vitro selection of mutants with decreased susceptibility to ertapenem was performed using Escherichia coli and Klebsiella pneumoniae clinical strains producing either the blaCTX-M-2, blaCTX-M-3, blaCTX-M-9, or blaCTX-M-15 gene. Frequencies of mutants with decreased susceptibilities to ertapenem were similar for all β-lactamases expressed.

  13. Overexpression of Salmonella enterica serovar Typhi recA gene confers fluoroquinolone resistance in Escherichia coli DH5α.

    Science.gov (United States)

    Yassien, M A M; Elfaky, M A

    2015-11-01

    A spontaneous fluoroquinolone-resistant mutant (STM1) was isolated from its parent Salmonella enterica serovar Typhi (S. Typhi) clinical isolate. Unlike its parent isolate, this mutant has selective resistance to fluoroquinolones without any change in its sensitivity to various other antibiotics. DNA gyrase assays revealed that the fluoroquinolone resistance phenotype of the STM1 mutant did not result from alteration of the fluoroquinolone sensitivity of the DNA gyrase isolated from it. To study the mechanism of fluoroquinolone resistance, a genomic library from the STM1 mutant was constructed in Escherichia coli DH5α and two recombinant plasmids were obtained. Only one of these plasmids (STM1-A) conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. The chromosomal insert from STM1-A, digested with EcoRI and HindIII restriction endonucleases, produced two DNA fragments and these were cloned separately into pUC19 thereby generating two new plasmids, STM1-A1 and STM1-A2. Only STM1-A1 conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. Sequence and subcloning analyses of STM1-A1 showed the presence of an intact RecA open reading frame. Unlike that of the wild-type E. coli DH5α, protein analysis of a crude STM1-A1 extract showed overexpression of a 40 kDa protein. Western blotting confirmed the 40 kDa protein band to be RecA. When a RecA PCR product was cloned into pGEM-T and introduced into E. coli DH5α, the STM1-A11 subclone retained fluoroquinolone resistance. These results suggest that overexpression of RecA causes selective fluoroquinolone resistance in E. coli DH5α. PMID:26375447

  14. Clonal relationship between human and avian ciprofloxacin-resistant Escherichia coli isolates in North-Eastern Algeria.

    Science.gov (United States)

    Agabou, A; Lezzar, N; Ouchenane, Z; Khemissi, S; Satta, D; Sotto, A; Lavigne, J-P; Pantel, A

    2016-02-01

    The objectives of this study were to determine rates, patterns, and mechanisms of antibiotic resistance, and to assess connections between chicken commensal, human commensal, and pathogenic ciprofloxacin-resistant Escherichia coli isolates. All E. coli isolates collected from chickens, their farmers, and patients in the Constantine region (North-east Algeria) were analyzed for bla and plasmid-mediated quinolone resistance (PMQR) gene contents, phylogroups, Rep-PCR profiles, and multilocus sequence types. A high prevalence of resistance to fluoroquinolones (51.4 % to ciprofloxacin) was recorded in avian isolates. Of these, 22.2 % carried the aac(6')-Ib-cr gene, whereas lower resistance levels to these antibiotics were recorded in chicken farmers' isolates. None of the commensal isolates harbored the qnr, qepA, or oqxAB genes. One human pathogenic isolate was ertapenem-resistant and harbored the bla OXA-48 gene, 84 showed an extended-spectrum β-lactamase phenotype, with bla CTX-M-15 gene prevalent in 87.2 % of them. Seventy isolates were resistant to fluoroquinolones, with aac(6')-Ib-cr present in 72.8 %, qnrB in 5.7 %, and qnrS in 10 %. Three Rep-PCR profiles were common to chicken commensal and human pathogenic isolates (phylogroups D and B1; ST21, ST48, and ST471 respectively); one was found in both chicken and chicken-farmer commensal strains (D; ST108), while another profile was identified in a chicken-farmer commensal strain and a human pathogenic one (B1; ST19). These findings suggest clonal and epidemiologic links between chicken and human ciprofloxacin-resistant E. coli isolates and the important role that poultry may play in the epidemiology of human E. coli infections in the Constantine region. PMID:26634353

  15. Study of the resistance mechanisms to ultraviolet light in Escherichia Coli. III. Genetic mapping of a mutation that confers resistance to radiation

    International Nuclear Information System (INIS)

    Inside this third work with respect to the investigation of the process of adaptation of different subcultures of Escherichia coli, to the UV light, its are present the obtained results in the identification of the gene or genes implied in the resistance to UV of one of the 5 populations derived for repeated exposure to growing dose of UV light of E. coli PQ30. Those obtained data indicate that the causing mutation of the phenotype is located in a single gene, since the insert of the fragment of DNA miniTn5 in this gene, causes the lost one from the resistance and the return to the original phenotype. The gene in question is denominated radA, located in the minute 99.6 of the chromosome of E. coli and required for the efficient repair of double ruptures in the DNA. (Author)

  16. Outer membrane proteomics of kanamycin-resistant Escherichia coli identified MipA as a novel antibiotic resistance-related protein.

    Science.gov (United States)

    Li, Hui; Zhang, Dan-feng; Lin, Xiang-min; Peng, Xuan-xian

    2015-06-01

    Antibiotic-resistant bacteria are a great threat to human health and food safety and there is an urgent need to understand the mechanisms of resistance for combating these bacteria. In the current study, comparative proteomic methodologies were applied to identify Escherichia coli K-12 outer membrane (OM) proteins related to kanamycin resistance. Mass spectrometry and western blotting results revealed that OM proteins TolC, Tsx and OstA were up-regulated, whereas MipA, OmpA, FadL and OmpW were down-regulated in kanamycin-resistant E. coli K-12 strain. Genetic deletion of tolC (ΔtolC-Km) led to a 2-fold decrease in the minimum inhibitory concentration (MIC) of kanamycin and deletion of mipA (ΔmipA-Km) resulted in a 4-fold increase in the MIC of kanamycin. Changes in the MICs for genetically modified strains could be completely recovered by gene complementation. Compared with the wild-type strain, the survival capability of ΔompA-Km was significantly increased and that of Δtsx-Km was significantly decreased. We further evaluated the role and expression of MipA in response to four other antibiotics including nalidixic acid, streptomycin, chloramphenicol and aureomycin, which suggested that MipA was a novel OM protein related to antibiotic resistance. PMID:25940639

  17. Seawater is a reservoir of multi-resistant Escherichia coli, including strains hosting plasmid-mediated quinolones resistance and extended-spectrum beta-lactamases genes

    Directory of Open Access Journals (Sweden)

    IsabelHenriques

    2014-08-01

    Full Text Available The aim of this study was to examine antibiotic resistance (AR dissemination in coastal water, considering the contribution of different sources of faecal contamination. Samples were collected in Berlenga, an uninhabited island classified as Natural Reserve and visited by tourists for aquatic recreational activities. To achieve our aim, AR in Escherichia coli isolates from coastal water was compared to AR in isolates from two sources of faecal contamination: human-derived sewage and seagull faeces. Isolation of E. coli was done on Chromocult agar. Based on genetic typing 414 strains were established. Distribution of E. coli phylogenetic groups was similar among isolates of all sources. Resistances to streptomycin, tetracycline, cephalothin and amoxicillin were the most frequent. Higher rates of AR were found among seawater and faeces isolates, except for last-line antibiotics used in human medicine. Multi-resistance rates in isolates from sewage and seagull faeces (29% and 32% were lower than in isolates from seawater (39%. Seawater AR profiles were similar to those from seagull faeces and differed significantly from sewage AR profiles. Nucleotide sequences matching resistance genes blaTEM, sul1, sul2, tet(A and tet(B, were present in isolates of all sources. Genes conferring resistance to 3rd generation cephalosporins were detected in seawater (blaCTX-M-1 and blaSHV-12 and seagull faeces (blaCMY-2. Plasmid-mediated determinants of resistance to quinolones were found: qnrS1 in all sources and qnrB19 in seawater and seagull faeces. Our results show that seawater is a relevant reservoir of AR and that seagulls are an efficient vehicle to spread human-associated bacteria and resistance genes. The E. coli resistome recaptured from Berlenga coastal water was mainly modulated by seagulls-derived faecal pollution. The repertoire of resistance genes covers antibiotics critically important for humans, a potential risk for human health.

  18. Adaptation mechanisms of Escherichia Coli to the ultraviolet light I. Isolation of mutants resistant to ultraviolet light; Mecanismos de adaptacion de Escherichia Coli a la luz ultravioleta I. Aislamiento de mutantes resistentes a luz ultravioleta

    Energy Technology Data Exchange (ETDEWEB)

    Alcantara D, D. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1995-09-15

    The objective of this work is to study the adaptation mechanisms of Escherichia coli to the ultraviolet light of 254 nm (W), a component of the solar light that induces a variety of damages in the DNA of the cells exposed, which should be eliminated in order to avoid its lethal and mutagenic effects. Inside this first report, the results obtained about the resistance to UV radiation of 5 independent populations of Escherichia coli, which were subjected in parallel form to 80 successive exposures of UV light with inserted periods of growth are reported. (Author)

  19. Predictability of Phenotype in Relation to Common β-Lactam Resistance Mechanisms in Escherichia coli and Klebsiella pneumoniae.

    Science.gov (United States)

    Agyekum, Alex; Fajardo-Lubián, Alicia; Ai, Xiaoman; Ginn, Andrew N; Zong, Zhiyong; Guo, Xuejun; Turnidge, John; Partridge, Sally R; Iredell, Jonathan R

    2016-05-01

    The minimal concentration of antibiotic required to inhibit the growth of different isolates of a given species with no acquired resistance mechanisms has a normal distribution. We have previously shown that the presence or absence of transmissible antibiotic resistance genes has excellent predictive power for phenotype. In this study, we analyzed the distribution of six β-lactam antibiotic susceptibility phenotypes associated with commonly acquired resistance genes in Enterobacteriaceae in Sydney, Australia. Escherichia coli (n = 200) and Klebsiella pneumoniae (n = 178) clinical isolates, with relevant transmissible resistance genes (blaTEM, n = 33; plasmid AmpC, n = 69; extended-spectrum β-lactamase [ESBL], n = 116; and carbapenemase, n = 100), were characterized. A group of 60 isolates with no phenotypic resistance to any antibiotics tested and carrying none of the important β-lactamase genes served as comparators. The MICs for all drug-bacterium combinations had a normal distribution, varying only in the presence of additional genes relevant to the phenotype or, for ertapenem resistance in K. pneumoniae, with a loss or change in the outer membrane porin protein OmpK36. We demonstrated mutations in ompK36 or absence of OmpK36 in all isolates in which reduced susceptibility to ertapenem (MIC, >1 mg/liter) was evident. Ertapenem nonsusceptibility in K. pneumoniae was most common in the context of an OmpK36 variant with an ESBL or AmpC gene. Surveillance strategies to define appropriate antimicrobial therapies should include genotype-phenotype relationships for all major transmissible resistance genes and the characterization of mutations in relevant porins in organisms, like K. pneumoniae. PMID:26912748

  20. Molecular epidemiology and antibiotic resistance pattern of Enteropathogenic Escherichia coli isolated from bovines and their handlers in Jammu, India

    Directory of Open Access Journals (Sweden)

    Majueeb U Rehman

    2014-12-01

    Full Text Available The study was aimed to investigate the molecular epidemiology and antibiotic resistance pattern of Enteropathogenic Escherichia coli (EPEC in bovines and their handlers in Jammu, India. A total of 173 samples comprising of 103 fecal samples from bovines (60 from cattle and 43 from buffaloes, 28 stools and 42 fingertip rinses from bovine handlers were collected during August 2011 to March 2012. The isolated 126 E. coli strains (86 from bovines and 40 from handlers belonged to 25 different serogroups in addition to rough and untypeable strains. Using multiplex polymerase chain reaction, four EPEC strains were isolated; two each from bovines and their handlers, of which two possessed the hemolysin (hlyA gene. The prevalence of EPEC was recorded as 1.66% (n=1/60 in cattle, 2.32% (n=1/43 in buffaloes, and 2.85% (n=2/70 in their handlers. Antibiogram studies with the EPEC revealed the presence of multi-drug resistant E. coli. The isolates were mostly resistant to Amikacin, Amoxicillin, Cefixime and Streptomycin, and sensitive to Chloramphenicol. This study indicates that bovines as well as their handlers in Jammu region harbor EPEC, many of which being multi-drug resistant and carrying the hemolysin gene could be of high pathogenic potential for humans.

  1. Modified Ponorogo bentonite for the removal of ampicillin from wastewater.

    Science.gov (United States)

    Rahardjo, Andi Kurniawan; Susanto, Maria Josephine Jeannette; Kurniawan, Alfin; Indraswati, Nani; Ismadji, Suryadi

    2011-06-15

    The adsorption of ampicillin onto natural and organo-bentonite was studied. Organo-bentonite was obtained by modifying the natural bentonite obtained from Ponorogo, Indonesia, using CTAB surfactant by microwave heating. The temperature dependent form of the Langmuir, Freundlich, Sips and Toth equations was employed to correlate equilibrium data. Based on the evaluation of the physical meaning of fitted isotherm parameters of each model, it is clear that Toth equation can represent the equilibrium data better than other models. The adsorption performance of natural and organo-bentonite for the removal of ampicillin from pharmaceutical company wastewater was also studied. In real wastewater, both adsorbents could not completely remove the ampicillin due to the sorption competition with other substances which also present in the wastewater. PMID:21550716

  2. Virulence factors, serogroups and antimicrobial resistance properties of Escherichia coli strains in fermented dairy products

    OpenAIRE

    Dehkordi, Farhad Safarpoor; Yazdani, Farshad; Mozafari, Jalal; Valizadeh, Yousef

    2014-01-01

    Background From a clinical perspective, it is essential to know the microbial safety of fermented dairy products. Doogh and kashk are fermented dairies. These products are used by millions of people but their microbial qualities are unknown. Shiga toxin producing Escherichia coli (STEC) is one of the most commonly detected pathogens in the cases of food poisoning and food-borne illnesses. The present investigation was carried out in order to study the molecular characterization and antimicrob...

  3. Antibiotic Resistance Patterns in Enteric and Uropathogenic Strains of Escherichia Coli in Children

    OpenAIRE

    This paper should be cited as: Sedighi I, Alikhani MY, Nakhaee S, Karami P . [ Antibiotic Resistance Patterns in Enteric and Uropathogenic Strains of Escherichia Coli in Children ]. mlj goums . 201 4 ; 8 ( Suppl 4 ): 42 - 48 [Article in Per sian] Sedi ghi, I. (MD); Alikhani, MY. (PhD); Nakhaee, S. (MD); Karami, P. (MSc

    2014-01-01

    Background and Objective: Escherichia coli is the most common cause of urinary tract infections in children and the leading cause of intra-abdominal infections (peritonitis and abscess) followed intestinal injuries. Urinary tract infection, including cystitis and pyelonephritis, is a common childhood infection. E. coli causes more than 90 percent of the community acquired and 50% of hospital acquired urinary tract infections; therefore, the determination of E. coli antibiotic susceptibility i...

  4. Tailoring Cytotoxicity of Antimicrobial Peptidomimetics with High Activity against Multidrug-Resistant Escherichia coli

    DEFF Research Database (Denmark)

    Jahnsen, Rasmus D; Sandberg-Schaal, Anne; Vissing, Karina Juul;

    2014-01-01

    Infections with multidrug-resistant pathogens are an increasing concern for public health. Recently, subtypes of peptide-peptoid hybrids were demonstrated to display potent activity against multidrug-resistant Gram-negative bacteria. Here, structural variation of these antibacterial peptidomimetics...... mammalian cells. Thus, lead compounds with a high selectivity toward killing of clinically important multidrug-resistant E. coli were identified....

  5. Genotypic Detection of Antibiotic Resistance in "Escherichia Coli.": A Classroom Exercise

    Science.gov (United States)

    Longtin, Sarah; Guilfoile, Patrick; Asper, Andrea

    2004-01-01

    Bacterial antibiotic resistance remains a problem of clinical importance. Current microbiological methods for determining antibiotic resistance are based on culturing bacteria, and may require up to 48 hours to complete. Molecular methods are increasingly being developed to speed the identification of antibiotic resistance and to determine its…

  6. Prevalence and characteristics of quinolone resistance in Escherichia coli in veal calves

    NARCIS (Netherlands)

    Hordijk, J.; Veldman, K.T.; Dierikx, C.M.; Essen-Zandbergen, van A.; Wagenaar, J.A.; Mevius, D.J.

    2012-01-01

    Quinolone resistance is studied and reported increasingly in isolates from humans, food-producing animals and companion animals. Resistance can be caused by chromosomal mutations in topoisomerase genes, plasmid-mediated resistance genes, and active transport through efflux pumps. Cross sectional dat

  7. Molecular cloning of an ornithine-activating fragment of the gramicidin S synthetase 2 gene from Bacillus brevis and its expression in Escherichia coli.

    OpenAIRE

    Krause, M.; Marahiel, M A; von Döhren, H; Kleinkauf, H

    1985-01-01

    Partially digested chromosomal DNA of Bacillus brevis ATCC 9999, a producer of the cyclic peptide antibiotic gramicidin S, was ligated into the BamHI site of the Escherichia coli expression vector pUR2-Bam. The ligated molecules were used to transfer E. coli to ampicillin resistance. Of 5 X 10(3) colonies tested by in situ immunoassay for a cross-reaction with antibodies against the gramicidin S synthetase 2, 6 colonies were found to be immunoreactive. A clone designated MK2, which had a 3.9-...

  8. Analysis of blaCTX-M-Carrying Plasmids from Escherichia coli Isolates Collected in the BfT-GermVet Study ▿

    OpenAIRE

    Schink, Anne-Kathrin; Kadlec, Kristina; Schwarz, Stefan

    2011-01-01

    In this study, 417 Escherichia coli isolates from defined disease conditions of companion and farm animals collected in the BfT-GermVet study were investigated for the presence of extended-spectrum β-lactamase (ESBL) genes. Three ESBL-producing E. coli isolates were identified among the 100 ampicillin-resistant isolates. The E. coli isolates 168 and 246, of canine and porcine origins, respectively, harbored blaCTX-M-1, and the canine isolate 913 harbored blaCTX-M-15, as confirmed by PCR and s...

  9. Effect of ethnomedicinal plants used in folklore medicine in Jordan as antibiotic resistant inhibitors on Escherichia coli

    Directory of Open Access Journals (Sweden)

    Aburjai Talal A

    2010-02-01

    Full Text Available Abstract Background Escherichia coli occurs naturally in the human gut; however, certain strains that can cause infections, are becoming resistant to antibiotics. Multidrug-resistant E. coli that produce extended-spectrum β lactamases (ESBLs, such as the CTX-M enzymes, have emerged within the community setting as an important cause of urinary tract infections (UTIs and bloodstream infections may be associated with these community-onsets. This is the first report testing the antibiotic resistance-modifying activity of nineteen Jordanian plants against multidrug-resistant E. coli. Methods The susceptibility of bacterial isolates to antibiotics was tested by determining their minimum inhibitory concentrations (MICs using a broth microdilution method. Nineteen Jordanian plant extracts (Capparis spinosa L., Artemisia herba-alba Asso, Echinops polyceras Boiss., Gundelia tournefortii L, Varthemia iphionoides Boiss. & Blanche, Eruca sativa Mill., Euphorbia macroclada L., Hypericum trequetrifolium Turra, Achillea santolina L., Mentha longifolia Host, Origanum syriacum L., Phlomis brachydo(Boiss. Zohary, Teucrium polium L., Anagyris foetida L., Trigonella foenum-graecum L., Thea sinensis L., Hibiscus sabdariffa L., Lepidium sativum L., Pimpinella anisum L. were combined with antibiotics, from different classes, and the inhibitory effect of the combinations was estimated. Results Methanolic extracts of the plant materials enhanced the inhibitory effects of chloramphenicol, neomycin, doxycycline, cephalexin and nalidixic acid against both the standard strain and to a lesser extent the resistant strain of E. coli. Two edible plant extracts (Gundelia tournefortii L. and Pimpinella anisum L. generally enhanced activity against resistant strain. Some of the plant extracts like Origanum syriacum L.(Labiateae, Trigonella foenum- graecum L.(Leguminosae, Euphorbia macroclada (Euphorbiaceae and Hibiscus sabdariffa (Malvaceae did not enhance the activity of

  10. Plasmid-mediated quinolone resistance determinants in quinolone-resistant Escherichia coli isolated from patients with bacteremia in a university hospital in Taiwan, 2001-2015.

    Science.gov (United States)

    Kao, Cheng-Yen; Wu, Hsiu-Mei; Lin, Wei-Hung; Tseng, Chin-Chung; Yan, Jing-Jou; Wang, Ming-Cheng; Teng, Ching-Hao; Wu, Jiunn-Jong

    2016-01-01

    The aim of this study was to characterize fluoroquinolone (FQ)-resistant Escherichia coli isolates from bacteremia in Taiwan in 2001-2015. During the study period, 248 (21.2%) of 1171 isolates were identified as levofloxacin-resistant. The results of phylogenetic group analysis showed that 38.7% of the FQ-resistant isolates belonged to phylogenetic group B2, 23.4% to group B1, 22.6% to groupA, 14.9% to group D, and 0.4% belonged to group F. FQ-resistant isolates were highly susceptible to cefepime (91.5%), imipenem (96.0%), meropenem (98.8%), amikacin (98.0%), and fosfomycin (99.6%), as determined by the agar dilution method. β-lactamases, including blaTEM (66.1%), blaCMY-2 (16.5%), blaCTX-M (5.2%), blaDHA-1 (1.6%), and blaSHV-12 (1.6%), were found in FQ-resistant isolates. The results of PCR and direct sequencing showed that 37 isolates (14.9%) harbored plasmid-mediated quinolone resistance (PMQR) genes. qnrB2, qnrB4, qnrS1, coexistence of qnrB4 and qnrS1, oqxAB, and aac(6')-Ib-cr were found in 1, 4, 4, 1, 15, and 14 isolates, respectively. PMQR genes were successfully transfered for 11 (29.7%) of the 37 PMQR-harboring isolates by conjugation to E. coli C600. These findings indicate that qnr genes remained rare in E. coli but demonstrate the potential spread of oqxAB and aac(6')-Ib-c in Taiwan. PMID:27573927

  11. The chromosomal arsenic resistance genes of Thiobacillus ferrooxidans have an unusual arrangement and confer increased arsenic and antimony resistance to Escherichia coli.

    Science.gov (United States)

    Butcher, B G; Deane, S M; Rawlings, D E

    2000-05-01

    The chromosomal arsenic resistance genes of the acidophilic, chemolithoautotrophic, biomining bacterium Thiobacillus ferrooxidans were cloned and sequenced. Homologues of four arsenic resistance genes, arsB, arsC, arsH, and a putative arsR gene, were identified. The T. ferrooxidans arsB (arsenite export) and arsC (arsenate reductase) gene products were functional when they were cloned in an Escherichia coli ars deletion mutant and conferred increased resistance to arsenite, arsenate, and antimony. Therefore, despite the fact that the ars genes originated from an obligately acidophilic bacterium, they were functional in E. coli. Although T. ferrooxidans is gram negative, its ArsC was more closely related to the ArsC molecules of gram-positive bacteria. Furthermore, a functional trxA (thioredoxin) gene was required for ArsC-mediated arsenate resistance in E. coli; this finding confirmed the gram-positive ArsC-like status of this resistance and indicated that the division of ArsC molecules based on Gram staining results is artificial. Although arsH was expressed in an E. coli-derived in vitro transcription-translation system, ArsH was not required for and did not enhance arsenic resistance in E. coli. The T. ferrooxidans ars genes were arranged in an unusual manner, and the putative arsR and arsC genes and the arsBH genes were translated in opposite directions. This divergent orientation was conserved in the four T. ferrooxidans strains investigated. PMID:10788346

  12. Plasmid and Host Strain Characteristics of Escherichia coli Resistant to Extended-Spectrum Cephalosporins in the Norwegian Broiler Production.

    Science.gov (United States)

    Mo, Solveig Sølverød; Slettemeås, Jannice Schau; Berg, Einar Sverre; Norström, Madelaine; Sunde, Marianne

    2016-01-01

    Escherichia coli resistant to extended-spectrum cephalosporins have been detected in the Norwegian broiler production, despite the fact that antimicrobial agents are rarely used. The genetic mechanism responsible for cephalosporin resistance is mainly attributed to the presence of the blaCMY-2 gene encoding a plasmid-mediated AmpC-beta-lactamase (pAmpC). The aim of this study was to characterize and compare blaCMY-2 containing Escherichia coli isolated from the intestinal flora of broilers and retail chicken meat (fillets) to identify possible successful clones and/or resistance plasmids widespread in the Norwegian broiler production. Methods used included PCR based phylotyping, conjugation experiments, plasmid replicon typing, pulsed-field gel electrophoresis, multiple locus variable-number tandem-repeats analysis and whole genome sequencing. The nucleotide sequence of an IncK plasmid carrying blaCMY-2 was determined. Intestinal isolates displayed a higher degree of genetic diversity than meat isolates. A cluster of genetically related isolates belonging to ST38, phylogroup D, carrying blaCMY-2 containing IncK plasmids was identified. Furthermore, genes encoding plasmid stability systems (relBE/stbDE and pndAC) were identified on the IncK plasmid. Single nucleotide polymorphism (SNP) analysis of a subset of isolates confirmed a close genetic relationship within the two most prevalent STs. The IncK plasmids within these two STs also shared a high degree of similarity. Cephalosporin-resistant E. coli with the same genetic characteristics have been identified in the broiler production in other European countries, and the IncK plasmid characterized in this study showed close homology to a plasmid isolated from retail chicken meat in the Netherlands. The results indicate that both clonal expansion and horizontal transfer of blaCMY-2 containing plasmids contribute to dissemination of cephalosporin resistant E. coli in the broiler production. The presence of plasmid

  13. Plasmid and Host Strain Characteristics of Escherichia coli Resistant to Extended-Spectrum Cephalosporins in the Norwegian Broiler Production

    Science.gov (United States)

    Mo, Solveig Sølverød; Slettemeås, Jannice Schau; Berg, Einar Sverre; Norström, Madelaine; Sunde, Marianne

    2016-01-01

    Escherichia coli resistant to extended-spectrum cephalosporins have been detected in the Norwegian broiler production, despite the fact that antimicrobial agents are rarely used. The genetic mechanism responsible for cephalosporin resistance is mainly attributed to the presence of the blaCMY-2 gene encoding a plasmid-mediated AmpC-beta-lactamase (pAmpC). The aim of this study was to characterize and compare blaCMY-2 containing Escherichia coli isolated from the intestinal flora of broilers and retail chicken meat (fillets) to identify possible successful clones and/or resistance plasmids widespread in the Norwegian broiler production. Methods used included PCR based phylotyping, conjugation experiments, plasmid replicon typing, pulsed-field gel electrophoresis, multiple locus variable-number tandem-repeats analysis and whole genome sequencing. The nucleotide sequence of an IncK plasmid carrying blaCMY-2 was determined. Intestinal isolates displayed a higher degree of genetic diversity than meat isolates. A cluster of genetically related isolates belonging to ST38, phylogroup D, carrying blaCMY-2 containing IncK plasmids was identified. Furthermore, genes encoding plasmid stability systems (relBE/stbDE and pndAC) were identified on the IncK plasmid. Single nucleotide polymorphism (SNP) analysis of a subset of isolates confirmed a close genetic relationship within the two most prevalent STs. The IncK plasmids within these two STs also shared a high degree of similarity. Cephalosporin-resistant E. coli with the same genetic characteristics have been identified in the broiler production in other European countries, and the IncK plasmid characterized in this study showed close homology to a plasmid isolated from retail chicken meat in the Netherlands. The results indicate that both clonal expansion and horizontal transfer of blaCMY-2 containing plasmids contribute to dissemination of cephalosporin resistant E. coli in the broiler production. The presence of plasmid

  14. Health risks associated with the presence of antibiotic resistant bacteria in greywater

    Directory of Open Access Journals (Sweden)

    Juan Moretton

    2012-04-01

    Full Text Available The removal and disposal of waste from domestic activities is a major health problem in densely populated urban areas. In many areas of Greater Buenos Aires, greywater is disposed in open ditches and risk potential of this has not been adequately quantified. The aim of this study was to evaluate the prevalence of antibiotic-resistant bacteria and its resistance profile present in raw greywater obtained from a channel located in the area of Ingeniero Budge Buenos Aires Province. Thus, the prevalence of heterotrophic bacteria, Gram-negative bacteria resistant to beta-lactam antibiotics and vancomycin-resistant enterococci in greywater, their typing, and resistance to other antibiotics were determined. The prevalence of resistant bacteria was determined by the agar dilution method. Of all the antibiotics tested, the highest prevalence of resistant heterotrophic bacteria was detected with cephalothin (19% and ampicillin (8%. With regard to Gram-negative bacteria, the highest prevalence of resistance was given by coliforms ampicillin (34% and cephalothin (17%. A total of 38% of enterococci with low level resistance to vancomycin was detected. The multiresistant isolates were identified as Escherichia coli, Alcaligenes faecalis y Stenotrophomonas maltophilia. These results indicate that greywater can be considered as a reservoir of bacteria resistant to antibiotics, thus increasing their health risk.

  15. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries

    DEFF Research Database (Denmark)

    Österberg, Julia; Wingstrand, Anne; Jensen, Annette Nygaard;

    2016-01-01

    Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in...... Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating...... conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in...

  16. Effective Phages as Green Antimicrobial Agents Against Antibiotic-Resistant Hospital Escherichia coli

    OpenAIRE

    Rahmani, Rana; Zarrini, Gholamreza; Sheikhzadeh, Farzam; Aghamohammadzadeh, Naser

    2015-01-01

    Background: Bacteriophages are viruses that attack bacteria and lead to their lysis in an efficient and highly specific manner. These natural enemies of bacteria were used as therapeutic agents before the advent of antibiotics. Currently, with the rapid spread of multi-drug resistant bacteria, phage therapy can be an effective alternative treatment for antibiotic resistant bacteria. Objectives: This study evaluated the effectiveness of bacteriophages in removing antibiotic-resistant clinical ...

  17. Surveillance and Detection of Inhibitor-Resistant Beta-Lactamases in Clinical Isolates of Escherichia coli

    OpenAIRE

    Carl Urban; Patricia Bradford; Joseph Villarin

    2007-01-01

    In recent years, resistance to beta-lactam antibiotics, such as the widely-used cephalosporins and penicillins, has become a major challenge for disease therapy, particularly in common hospital-acquired infections. In the search for the mechanisms behind this increasingly prevalent form of resistance, microbiologists have identified a new type of beta-lactamase enzyme, called inhibitor-resistant TEMs (IRTs), which can withstand the effects of beta-lactamase inhibitor compounds, further reduci...

  18. Differential Epigenetic Compatibility of qnr Antibiotic Resistance Determinants with the Chromosome of Escherichia coli

    OpenAIRE

    Sánchez, María B.; Martínez, José L.

    2012-01-01

    Environmental bacteria harbor a plethora of genes that, upon their horizontal transfer to new hosts, may confer resistance to antibiotics, although the number of such determinants actually acquired by pathogenic bacteria is very low. The founder effect, fitness costs and ecological connectivity all influence the chances of resistance transfer being successful. We examined the importance of these bottlenecks using the family of quinolone resistance determinants Qnr. The results indicate the ep...

  19. Identification and antimicrobial resistance prevalence of pathogenic Escherichia coli strains from treated wastewater effluents in Eastern Cape, South Africa.

    Science.gov (United States)

    Adefisoye, Martins A; Okoh, Anthony I

    2016-02-01

    Antimicrobial resistance (AMR) is a global problem impeding the effective prevention/treatment of an ever-growing array of infections caused by pathogens; a huge challenge threatening the achievements of modern medicine. In this paper, we report the occurrence of multidrug resistance (MDR) in Escherichia coli strains isolated from discharged final effluents of two wastewater treatment facilities in the Eastern Cape Province of South Africa. Standard disk diffusion method was employed to determine the antibiotic susceptibility profile of 223 polymerase chain reaction (PCR)-confirmed E. coli isolates against 17 common antibiotics in human therapy and veterinary medicine. Seven virulence associated and fourteen antibiotic resistance genes were also evaluated by molecular methods. Molecular characterization revealed five pathotypes of E. coli in the following proportions: enterotoxigenic ETEC (1.4%), enteropathogenic EPEC (7.6%), enteroaggregative EAEC (7.6%), neonatal meningitis (NMEC) (14.8%), uropathogenic (41.7%), and others (26.9%). Isolates showed varying (1.7-70.6%) degrees of resistance to 15 of the test antibiotics. Multidrug resistance was exhibited by 32.7% of the isolates, with the commonest multiple antibiotic-resistant phenotype (MARP) being AP-T-CFX (12 isolates), while multiple antibiotic-resistant indices (MARI) estimated are 0.23 (Site 1) and 0.24 (Site 2). Associated antibiotic resistance genes detected in the isolates include: strA (88.2%), aadA (52.9%), cat I (15%), cmlA1 (4.6%), blaTEM (56.4%), tetA (30.4%), tetB (28.4%), tetC (42.2%), tetD (50%), tetK (11.8%), and tetM (68.6%). We conclude that municipal wastewater effluents are important reservoirs for the dissemination of potentially pathogenic E. coli (and possibly other pathogens) and antibiotic resistance genes in the aquatic milieu of the Eastern Cape and a risk to public health. PMID:26758686

  20. Prevalence and Risk Factors for Colonization With Extended-Spectrum Cephalosporin-Resistant Escherichia coli in Children Attending Daycare Centers : A Cohort Study in the Netherlands

    NARCIS (Netherlands)

    Koningstein, Maike; Leenen, Margriet A; Mughini-Gras, Lapo; Scholts, Rianne M C; van Huisstede-Vlaanderen, Kirstin W; Enserink, Remko; Zuidema, Rody; Kooistra-Smid, Mirjam A M D; Veldman, Kees; Mevius, Dik; van Pelt, Wilfrid

    2015-01-01

    BACKGROUND: The purpose of this study was to determine the prevalence and risk factors for colonization with extended-spectrum cephalosporin-resistant (ESC-R) Escherichia coli in daycare center (DCC)-attending children. METHODS: This is a prospective cohort study including 44 DCCs in the Netherlands

  1. Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains Isolated from Farm Animals from 1999 to 2002: Report from the Japanese Veterinary Antimicrobial Resistance Monitoring Program

    OpenAIRE

    Kojima, Akemi; Ishii, Yoshikazu; Ishihara, Kanako; Esaki, Hidetake; Asai, Tetsuo; Oda, Chitose; Tamura, Yutaka; Takahashi, Toshio; Yamaguchi, Keizo

    2005-01-01

    A nationwide surveillance for antimicrobial susceptibility in Escherichia coli strains isolated from food-producing animals in Japan was conducted from 1999 to 2002. Eighteen cefazolin-resistant E. coli strains were isolated from broilers. Six were CTX-M-type producing, and eight were CMY-2 producing, while eight had mutations at the ampC promoter region.

  2. Mixed biofilm formation by Shiga toxin-producing Escherichia coli and Salmonella enterica serovar typhimurium enhanced bacterial resistance to sanitization due to extracellular polymeric substances

    Science.gov (United States)

    Shiga toxin–producing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium are important foodborne pathogens capable of forming single-species biofilms or coexisting in multispecies biofilm communities. Bacterial biofilm cells are usually more resistant to sanitization than their pla...

  3. The role of RNA polymerase sigma-factor (RpoS) in induction of glutamate-dependent acid-resistance of Escherichia albertii under anaerobic conditions

    Science.gov (United States)

    Escherichia albertii is a potential enteric foodborne pathogen with poorly defined genetic and biochemical properties. Acid resistance is perceived to be an important property of enteric pathogens, enabling them to survive passage through stomach acidity so that they may colonize the mammalian gast...

  4. Relation between tetR and tetA expression in tetracycline resistant Escherichia coli

    DEFF Research Database (Denmark)

    Møller, Thea S. B.; Overgaard, Martin; Nielsen, Søren S.;

    2016-01-01

    Background: Tetracyclines are among the most used antibiotics in livestock worldwide. Resistance is widely disseminated in Escherichia coli, where it is generally mediated by tetracycline efflux pumps, such as TetA. Expression of tetracycline efflux pumps is tightly controlled by the repressor Te...

  5. Detection of mcr-1 encoding plasmid-mediated colistin-resistant Escherichia coli isolates from human bloodstream infection and imported chicken meat, Denmark 2015

    DEFF Research Database (Denmark)

    Hasman, H.; Hammerum, A. M.; Hansen, F.;

    2015-01-01

    The plasmid-mediated colistin resistance gene, mcr-1, was detected in an Escherichia coli isolate from a Danish patient with bloodstream infection and in five E. coli isolates from imported chicken meat. One isolate from chicken meat belonged to the epidemic spreading sequence type ST131. In...

  6. Isolation of Escherichia coli rpoB mutants resistant to killing by lambda cII protein and altered in pyrE gene attenuation

    DEFF Research Database (Denmark)

    Hammer, Karin; Jensen, Kaj Frank; Poulsen, Peter;

    1987-01-01

    Escherichia coli mutants simultaneously resistant to rifampin and to the lethal effects of bacteriophage lambda cII protein were isolated. The sck mutant strains carry alterations in rpoB that allow them to survive cII killing (thus the name sck), but that do not impair either the expression of c...

  7. Substrate specificity of the OqxAB multidrug resistance pump in Escherichia coli and selected enteric bacteria

    DEFF Research Database (Denmark)

    Hansen, Lars Hestbjerg; Jensen, Lars Bogø; Sørensen, Heidi Iskou;

    2007-01-01

    Objectives: A plasmid-encoded multidrug eff lux pump, OqxAB, identified in Escherichia coli of porcine origin, was tested for substrate specificity against selected antibiotics, detergents and disinfectants. The ability of horizontal transfer to food-borne pathogens of the Enterobacteriaceae family...... Typhimurium, Klebsiella pneumoniae, Kluyvera sp. and Enterobacter aerogrenes was investigated. The effect of the presence of the OqxAB pump on susceptibility for selected compounds was investigated using broth dilution assays. Results: The OqxAB pump conferred antimicrobial resistance or reduced....... Conclusions: The plasmid-encoded OqxAB pump has a wide substrate specificity and can be transferred between Enterobacteriaceae conferring reduced susceptibility to a multitude of substrates. These results could indicate some dependence on the outer membrane proteins present in the different species....

  8. Pathways of Resistance to Thymineless Death in Escherichia coli and the Function of UvrD

    OpenAIRE

    Fonville, Natalie C.; Vaksman, Zalman; DeNapoli, Jessica; Hastings, P. J.; Rosenberg, Susan M.

    2011-01-01

    Thymineless death (TLD) is the rapid loss of viability in bacterial, yeast, and human cells starved of thymine. TLD is the mode of action of common anticancer drugs and some antibiotics. TLD in Escherichia coli is accompanied by blocked replication and chromosomal DNA loss and recent work identified activities of recombination protein RecA and the SOS DNA-damage response as causes of TLD. Here, we examine the basis of hypersensitivity to thymine deprivation (hyper-TLD) in mutants that lack th...

  9. Virulence repertoire, characterization, and antibiotic resistance pattern analysis of Escherichia coli isolated from backyard layers and their environment in India.

    Science.gov (United States)

    Samanta, Indranil; Joardar, Siddhartha N; Das, Pradip K; Das, Palas; Sar, Tapas K; Dutta, Tapan K; Bandyopadhyay, Samiran; Batabyal, Subhasis; Isore, Devi P

    2014-03-01

    This study was undertaken to observe the prevalence, serogroup, avian pathogenic Escherichia coli (APEC)-associated virulence gene, randomly amplified polymorphic DNA (RAPD) pattern, and antibiotic resistance genes of E. coli in backyard layers and their environment in India. From the 360 samples of healthy layers and their environment, 272 (75.5%) E. coli were isolated. The majority (28.67%) of them were untypeable. Among the studied virulence genes (papC, tsh, iucC, astA), 52 (14.32%) isolates were found to possess astA, including the isolates from the drinking water of the birds (4/272, 1.47%). These strains belonged to 18 different serogroups. Most of the isolates were typeable by RAPD and they produced different patterns. Phenotypic resistance of the isolates was most frequently observed to erythromycin (95.83%), chloramphenicol (87.52%), and cotrimoxazole (78.26%). None of the isolates was found to possess extended-spectrum beta-lactamases (bla(TEM), bla(SHV), bla(CTX-M) or quinolone resistance (qnrA) genes by PCR. The present study was the first attempt in India to assess APEC distribution in backyard poultry production. PMID:24758111

  10. Emissions of Escherichia coli Carrying Extended-Spectrum β-Lactamase Resistance from Pig Farms to the Surrounding Environment

    Directory of Open Access Journals (Sweden)

    Lili Gao

    2015-04-01

    Full Text Available The dissemination of extended-spectrum β-lactamase (ESBL-producing Escherichia coli (E. coli from food-producing animals to the surrounding environment has attracted much attention. To determine the emissions of ESBL-producing E. coli from pig farms to the surrounding environment, fecal and environmental samples from six pig farms were collected. In total, 119 ESBL-producing E. coli were isolated from feces, air samples, water, sludge and soil samples. Antibiotic susceptibility testing showed that the ESBL-producing isolates were resistant to multiple antibiotics and isolates of different origin within the same farm showed similar resistance phenotypes. Both CTX-M and TEM ESBL-encoding genes were detected in these isolates. CTX-M-14 and CTX-M-15 were the predominant ESBL genes identified. ESBL producers from feces and environmental samples within the same farm carried similar CTX-M types. The results indicated that the ESBL-producing E. coli carrying multidrug resistance could readily disseminate to the surrounding environment.

  11. Cefoxitin resistance mediated by loss of a porin in clinical strains of Klebsiella pneumoniae and Escherichia coli

    Directory of Open Access Journals (Sweden)

    Ananthan S

    2005-01-01

    Full Text Available PURPOSE: Porins are outer membrane protein (OMP that form water filled channels that permit the diffusion of small hydrophilic solutes like -lactam antibiotics across the outer membrane. Two major porins that facilitate diffusion of antimicrobials have been described in Klebsiella spp. and Escherichia coli. The present study was carried out to examine the role of porins among Extended Spectrum -Lactamase (ESBL and AmpC -Lactamase positive strains of Klebsiella spp. and E.coli. METHODS: Preparation of OMP from phenotypically characterized clinical isolates K.pneumoniae and E.coli and the separation of the proteins by sodium dodecyl sulfate - polyacrylamide gel electrophoresis were performed as per a previously described procedure. RESULTS: OMP analysis revealed that cefoxitin and ceftazidime resistance was mediated by loss of a porin Omp K35 in the isolates of K.pneumoniae and E.coli. CONCLUSIONS: Loss of porin mediated resistance mechanism against cefoxitin was observed among the multidrug resistant K.pneumoniae and E.coli.

  12. Variable tellurite resistance profiles of clinically-relevant Shiga toxin-producing Escherichia coli (STEC) influence their recovery from foodstuffs.

    Science.gov (United States)

    Kerangart, Stéphane; Douëllou, Thomas; Delannoy, Sabine; Fach, Patrick; Beutin, Lothar; Sergentet-Thévenot, Delphine; Cournoyer, Benoit; Loukiadis, Estelle

    2016-10-01

    Tellurite (Tel)-amended selective media and resistance (Tel-R) are widely used for detecting Shiga toxin-producing Escherichia coli (STEC) from foodstuffs. Tel-R of 81 O157 and non-O157 STEC strains isolated from animal, food and human was thus investigated. Variations of STEC tellurite minimal inhibitory concentration (MIC) values have been observed and suggest a multifactorial and variable tellurite resistome between strains. Some clinically-relevant STEC were found highly susceptible and could not be recovered using a tellurite-based detection scheme. The ter operon was highly prevalent among highly Tel-R STEC but was not always detected among intermediately-resistant strains. Many STEC serogroup strains were found to harbor sublines showing a gradient of MIC values. These Tel-R sublines showed statistically significant log negative correlations with increasing tellurite concentration. Whatever the tellurite concentration, the highest number of resistant sublines was observed for STEC belonging to the O26 serogroup. Variations in the number of these Tel-R sublines could explain the poor recovery of some STEC serogroups on tellurite-amended media especially from food products with low levels of contamination. Comparison of tellurite MIC values and distribution of virulence-related genes showed Tel-R and virulence to be related. PMID:27375242

  13. Characterisation, dissemination and persistence of gentamicin resistant Escherichia coli from a Danish university hospital to the waste water environment

    DEFF Research Database (Denmark)

    Jakobsen, Lotte; Sandvang, Dorthe; Hansen, Lars H;

    2008-01-01

    The aim of the study was to investigate the potential spread of gentamicin resistant (GEN(R)) Escherichia coli isolates or GEN(R) determinants from a Danish university hospital to the waste water environment. Waste water samples were collected monthly from the outlets of the hospital bed wards an...... water. Most of the GEN(R)E. coli isolates from both patients and waste water had a multi-resistant phenotype and contained virulence genes and should therefore be considered reservoirs of antimicrobial resistance and virulence genes....... the inlet of the related waste water treatment plant (WWTP) from October 2002 to August 2003. Waste water samples were also collected monthly from a residential area in the same period to be able to compare the prevalence of GEN(R)E. coli isolates from hospital related and residential waste water. The...... waste water isolates were compared to GEN(R)E. coli isolates obtained consecutively from September 2002 to September 2003 from patients mainly with urinary tract infections at the hospital with respect to Pulsed Field Gel Electrophoresis (PFGE) profiles. All isolates were investigated for GEN...

  14. Comparison of the selection of antimicrobial resistance in fecal Escherichia coli during enrofloxacin administration with a local drug delivery system or with intramuscular injections in a swine model

    OpenAIRE

    Béraud, Romain; Huneault, Louis; Bernier, Dave; Beaudry, Francis; Letellier, Ann; del Castillo, Jérôme R.E.

    2008-01-01

    This study evaluated, for the first time, the selection of antibiotic resistance in fecal Escherichia coli, a potential reservoir of genes of resistance, during the prolonged exposure to fluoroquinolones after the implantation of a local drug delivery system (LDDS) in a swine model. Fourteen pigs were randomly assigned to group IM (5 mg/kg/day of intramuscular enrofloxacin — EFX) or LD (surgical implantation of EFX-polymethyl-methacrylate perifemoral implants). Blood samples were collected da...

  15. Molecular characterization of vancomycin-resistant enterococci and extended-spectrum beta-lactamase-containing Escherichia coli isolates in wild birds from the Azores Archipelago

    OpenAIRE

    2011-01-01

    Abstract To study the prevalence of vancomycin-resistant enterococci (VRE) and extended-spectrum beta-lactamases (ESBLs) containing Escherichia coli isolates, and the mechanisms of resistance implicated, 220 faecal samples from wild birds were collected between 2006 and 2010 in the Azores Archipelago. Samples were spread in Slanetz-Bartley agar plates supplemented with 4 mg/L of vancomycin and in Levine agar plates supplemented with 2 mg/L of cefotaxime for VRE and ESBL-containing ...

  16. Molecular characterization and drug resistance of Escherichia coli strains isolated from urine from long-term care facility residents in Cracow, Poland

    OpenAIRE

    Pobiega, Monika; Wojkowska-Mach, Jadwiga; Chmielarczyk, Agnieszka; Romaniszyn, Dorota; Adamski, Paweł; Heczko, Piort B.; Gryglewska, Barbara; Grodzicki, Tomasz

    2013-01-01

    Background The aim of this study was to assess the prevalence of multidrug-resistant Escherichia coli and extended-spectrum β-lactamases (ESBL) pathogens isolated from asymptomatic bacteriuria and urinary tract infections (UTIs), and the relationship between the phylogeny, antimicrobial resistance, and virulence among isolates in residents of 3 long-term care facilities (LTCF) in Krakow, Poland. Material/Methods This was point prevalence study and prospective infection control in a group of 2...

  17. Molecular Characterization of Resistance to Extended-Spectrum Cephalosporins in Clinical Escherichia coli Isolates from Companion Animals in the United States ▿ †

    OpenAIRE

    Shaheen, Bashar W.; Nayak, Rajesh; Foley, Steven L.; Kweon, Ohgew; Deck, Joanna; Park, Miseon; Rafii, Fatemeh; Boothe, Dawn M.

    2011-01-01

    Resistance to extended-spectrum cephalosporins (ESC) among members of the family Enterobacteriaceae occurs worldwide; however, little is known about ESC resistance in Escherichia coli strains from companion animals. Clinical isolates of E. coli were collected from veterinary diagnostic laboratories throughout the United States from 2008 to 2009. E. coli isolates (n = 54) with reduced susceptibility to ceftazidime or cefotaxime (MIC ≥ 16 μg/ml) and extended-spectrum-β-lactamase (ESBL) phenotyp...

  18. Association of Veterinary Third-Generation Cephalosporin Use with the Risk of Emergence of Extended-Spectrum-Cephalosporin Resistance in Escherichia coli from Dairy Cattle in Japan

    OpenAIRE

    Sato, Toyotaka; Okubo, Torahiko; Usui, Masaru; Yokota, Shin-ichi; Izumiyama, Satoshi; Tamura, Yutaka

    2014-01-01

    The use of extended-spectrum cephalosporins in food animals has been suggested to increase the risk of spread of Enterobacteriaceae carrying extended-spectrum β-lactamases to humans. However, evidence that selection of extended-spectrum cephalosporin–resistant bacteria owing to the actual veterinary use of these drugs according to criteria established in cattle has not been demonstrated. In this study, we investigated the natural occurrence of cephalosporin-resistant Escherichia coli in dairy...

  19. Genome Sequence of Avian Escherichia coli Strain IHIT25637, an Extraintestinal Pathogenic E. coli Strain of ST131 Encoding Colistin Resistance Determinant MCR-1.

    Science.gov (United States)

    Ewers, Christa; Göttig, Stephan; Bülte, Maria; Fiedler, Sophie; Tietgen, Manuela; Leidner, Ursula; Heydel, Carsten; Bauerfeind, Rolf; Semmler, Torsten

    2016-01-01

    Sequence type 131 (ST131) is one of the predominant Escherichia coli lineages among extraintestinal pathogenic E. coli (ExPEC) that causes a variety of diseases in humans and animals and frequently shows multidrug resistance. Here, we report the first genome sequence of an ST131-ExPEC strain from poultry carrying the plasmid-encoded colistin resistance gene mcr-1. PMID:27587807

  20. Commonality among Fluoroquinolone-Resistant Sequence Type ST131 Extraintestinal Escherichia coli Isolates from Humans and Companion Animals in Australia▿†

    OpenAIRE

    Platell, Joanne L.; Cobbold, Rowland N.; Johnson, James R.; Heisig, Anke; Heisig, Peter; Clabots, Connie; Kuskowski, Michael A.; Trott, Darren J

    2011-01-01

    Escherichia coli sequence type 131 (ST131), an emergent multidrug-resistant extraintestinal pathogen, has spread epidemically among humans and was recently isolated from companion animals. To assess for human-companion animal commonality among ST131 isolates, 214 fluoroquinolone-resistant extraintestinal E. coli isolates (205 from humans, 9 from companion animals) from diagnostic laboratories in Australia, provisionally identified as ST131 by PCR, selectively underwent PCR-based O typing and ...

  1. Apramycin treatment affects selection and spread of a multidrug-resistant Escherichia coli strain able to colonize the human gut in the intestinal microbiota of pigs

    DEFF Research Database (Denmark)

    Herrero-Fresno, Ana; Zachariasen, Camilla; Hansen, Monica Hegstad;

    2016-01-01

    The effect of apramycin treatment on transfer and selection of an Escherichia coli strain (E. coli 912) in the intestine of pigs was analyzed through an in vivo experiment. The strain was sequenced and assigned to the sequence type ST101 and serotype O11. It carried resistance genes to apramycin......-resistant E. coli. Since gentamicin is a first-choice drug for human bacteremia, this is of concern....

  2. β-Lactamases Responsible for Resistance to Expanded-Spectrum Cephalosporins in Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis Isolates Recovered in South Africa

    OpenAIRE

    J.D.D. Pitout; Thomson, K S; Hanson, N D; Ehrhardt, A F; Moland, E S; Sanders, C C

    1998-01-01

    Although resistance to the expanded-spectrum cephalosporins among members of the family Enterobacteriaceae lacking inducible β-lactamases occurs virtually worldwide, little is known about this problem among isolates recovered in South Africa. Isolates of Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis resistant to expanded-spectrum cephalosporins recovered from patients in various parts of South Africa over a 3-month period were investigated for extended-spectrum β-lactamase pr...

  3. Resistance of uropathogenic strains of Escherichia coli in pregnant women and other women in generative ages in comparison with antibiotics consumption in Zagreb

    OpenAIRE

    Marcel Leppée,; Ana Mlinarić-Džepina,; Josip Čulig; Jasmina Vraneš,

    2010-01-01

    Aim To compare resistance of uropathogenic strains of Escherichia coli (UPEC) to antibiotics in women in generative ages and pregnant women during two year period (2004 and 2008) in Zagreb, andcomparison of resistance and the consumption of antibiotics. Methods The standard disk-diffusion method was used for sensitivity testing to 16 different antibiotics.Data on antibiotic utilization were used to calculate the number of defined daily doses (DDD) and DDD per 1000 inhabitants using Anatomical...

  4. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    OpenAIRE

    Nguyen, V.T.; CARRIQUE-MAS, J. J.; Ngo, T.H; Ho, H M; Ha, T.T.; CAMPBELL, J. I.; Nguyen, T N; Hoang, N.N.; PHAM, V. M.; Wagenaar, J. A.; Hardon, A.; Thai, Q.H.; Schultsz, C

    2015-01-01

    Objectives: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. Methods: We collected data on farming and antimicrobial usage from 208 chicken farms. E. coli was isolated from boot swab samples using MacConkey agar (MA) and MA with ceftazidime, nalidixic acid or gentam...

  5. Silent dissemination of colistin-resistant Escherichia coli in South America could contribute to the global spread of the mcr-1 gene.

    Science.gov (United States)

    Fernandes, Miriam R; Moura, Quezia; Sartori, Luciana; Silva, Ketrin C; Cunha, Marcos Pv; Esposito, Fernanda; Lopes, Ralf; Otutumi, Luciana K; Gonçalves, Daniela D; Dropa, Milena; Matté, Maria H; Monte, Daniel Fm; Landgraf, Mariza; Francisco, Gabriela R; Bueno, Maria Fc; de Oliveira Garcia, Doroti; Knöbl, Terezinha; Moreno, Andrea M; Lincopan, Nilton

    2016-04-28

    During a Brazilian multicentric antimicrobial resistance surveillance study, colistin resistance was investigated in 4,620 Enterobacteriaceae isolated from human, animal, food and environmental samples collected from 2000 to 2016. We present evidence that mcr-1-positive Escherichia coli has been emerging in South America since at least 2012, supporting a previous report on the possible acquisition of mcr-1-harbouring E. coli by European travellers visiting Latin American countries. PMID:27168587

  6. Genome Sequence of Avian Escherichia coli Strain IHIT25637, an Extraintestinal Pathogenic E. coli Strain of ST131 Encoding Colistin Resistance Determinant MCR-1

    Science.gov (United States)

    Göttig, Stephan; Bülte, Maria; Fiedler, Sophie; Tietgen, Manuela; Leidner, Ursula; Heydel, Carsten; Bauerfeind, Rolf; Semmler, Torsten

    2016-01-01

    Sequence type 131 (ST131) is one of the predominant Escherichia coli lineages among extraintestinal pathogenic E. coli (ExPEC) that causes a variety of diseases in humans and animals and frequently shows multidrug resistance. Here, we report the first genome sequence of an ST131-ExPEC strain from poultry carrying the plasmid-encoded colistin resistance gene mcr-1. PMID:27587807

  7. Intestinal microbiota shifts towards elevated commensal Escherichia coli loads abrogate colonization resistance against Campylobacter jejuni in mice.

    Directory of Open Access Journals (Sweden)

    Lea-Maxie Haag

    Full Text Available BACKGROUND: The zoonotic pathogen Campylobacter jejuni is a leading cause of bacterial foodborne enterocolitis in humans worldwide. The understanding of immunopathology underlying human campylobacteriosis is hampered by the fact that mice display strong colonization resistance against the pathogen due to their host specific gut microbiota composition. METHODOLOGY/PRINCIPAL FINDINGS: Since the microbiota composition changes significantly during intestinal inflammation we dissected factors contributing to colonization resistance against C. jejuni in murine ileitis, colitis and in infant mice. In contrast to healthy animals C. jejuni could stably colonize mice suffering from intestinal inflammation. Strikingly, in mice with Toxoplasma gondii-induced acute ileitis, C. jejuni disseminated to mesenteric lymphnodes, spleen, liver, kidney, and blood. In infant mice C. jejuni infection induced enterocolitis. Mice suffering from intestinal inflammation and C. jejuni susceptible infant mice displayed characteristical microbiota shifts dominated by increased numbers of commensal Escherichia coli. To further dissect the pivotal role of those distinct microbiota shifts in abrogating colonization resistance, we investigated C. jejuni infection in healthy adult mice in which the microbiota was artificially modified by feeding live commensal E. coli. Strikingly, in animals harboring supra-physiological intestinal E. coli loads, colonization resistance was significantly diminished and C. jejuni infection induced enterocolitis mimicking key features of human campylobacteriosis. CONCLUSION/SIGNIFICANCE: Murine colonization resistance against C. jejuni is abrogated by changes in the microbiota composition towards elevated E. coli loads during intestinal inflammation as well as in infant mice. Intestinal inflammation and microbiota shifts thus represent potential risk factors for C. jejuni infection. Corresponding interplays between C. jejuni and microbiota might

  8. The Widespread Presence of a Multidrug-Resistant Escherichia coli ST131 Clade among Community-Associated and Hospitalized Patients.

    Directory of Open Access Journals (Sweden)

    P Martijn den Reijer

    Full Text Available The extent of entry of multidrug-resistant Escherichia coli from the community into the hospital and subsequent clonal spread amongst patients is unclear. To investigate the extent and direction of clonal spread of these bacteria within a large teaching hospital, we prospectively genotyped multidrug-resistant E. coli obtained from community- and hospital associated patient groups and compared the distribution of diverse genetic markers.A total of 222 E. coli, classified as multi-drug resistant according to national guidelines, were retrieved from both screening (n = 184 and non-screening clinical cultures (n = 38 from outpatients and patients hospitalized for various periods. All isolates were routinely genotyped using an amplified fragment length polymorphism (AFLP assay and real-time PCR for CTX-M genes. Multi-locus sequence typing was additionally performed to confirm clusters. Based on demographics, patients were categorized into two groups: patients that were not hospitalized or less than 72 hours at time of strain isolation (group I and patients that were hospitalized for at least 72 hours (group II.Genotyping showed that most multi-drug resistant E. coli either had unique AFLP profiles or grouped in small clusters of maximally 8 isolates. We identified one large ST131 clade comprising 31% of all isolates, containing several AFLP clusters with similar profiles. Although different AFLP clusters were found in the two patient groups, overall genetic heterogeneity was similar (35% vs 28% of isolates containing unique AFLP profiles, respectively. In addition, similar distributions of CTX-M groups, including CTX-M 15 (40% and 44% of isolates in group I and II, respectively and ST131 (32% and 30% of isolates, respectively were found.We conclude that multi-drug resistant E. coli from the CTX-M 15 associated lineage ST131 are widespread amongst both community- and hospital associated patient groups, with similar genetic diversity and similar

  9. Human Health Hazards from Antimicrobial-Resistant Escherichia coli of Animal Origin

    DEFF Research Database (Denmark)

    Hammerum, A. M.; Heuer, Ole Eske

    2009-01-01

    antimicrobial agents in food animals may add to the burden of antimicrobial resistance in humans. Bacteria from the animal reservoir that carry resistance to antimicrobial agents that are regarded as highly or critically important in human therapy (e.g., aminoglycosides, fluoroquinolones, and third- and fourth...

  10. Adaptive Evolution of Escherichia coli to an α-Peptide/β-Peptoid Peptidomimetic Induces Stable Resistance

    DEFF Research Database (Denmark)

    Hein-Kristensen, Line; Franzyk, Henrik; Holch, Anne;

    2013-01-01

    returned to wild-type level upon addition of 25% plasma. Whole-genome sequencing of twenty isolates from four resistant lineages revealed mutations, in murein transglycosylase D (mltD) and outer-membrane proteins, which were conserved within and between lineages. However, no common resistance...

  11. Antimicrobial resistance and spread of multi drug resistant Escherichia coli isolates collected from nine urology services in the Euregion Meuse-Rhine.

    Directory of Open Access Journals (Sweden)

    Christina F M van der Donk

    Full Text Available We determined the prevalence and spread of antibiotic resistance and the characteristics of ESBL producing and/or multi drug resistant (MDR Escherichia coli isolates collected from urine samples from urology services in the Euregio Meuse-Rhine, the border region of the Netherlands (n=176, Belgium (n=126 and Germany (n=119. Significant differences in resistance between the three regions were observed. Amoxicillin-clavulanic acid resistance ranged from 24% in the Netherlands to 39% in Belgium (p=0.018, from 20% to 40% (p<0.004 for the fluoroquinolones and from 20% to 40% (p=0.018 for the folate antagonists. Resistance to nitrofurantoin was less than 5%. The prevalence of ESBL producing isolates varied from 2% among the Dutch isolates to 8% among the German ones (p=0.012 and were mainly CTX-M 15. The prevalence of MDR isolates among the Dutch, German and Belgian isolates was 11%, 17% and 27%, respectively (p< =0.001 for the Belgian compared with the Dutch isolates. The majority of the MDR and ESBL producing isolates belonged to ST131. This study indicates that most antibiotics used as first choice oral empiric treatment for UTIs (amoxicillin-clavulanic acid, fluoroquinolones and folate antagonists are not appropriate for this purpose and that MDR strains such as CTX-M producing ST131 have spread in the entire Euregion. Our data stress the importance of ward specific surveillance to optimize empiric treatment. Also, prudent use of antibiotics and further research to alternative agents are warranted.

  12. Decrypting the H-NS-dependent regulatory cascade of acid stress resistance in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Soutourina Olga

    2010-10-01

    Full Text Available Abstract Background H-NS regulates the acid stress resistance. The present study aimed to characterize the H-NS-dependent cascade governing the acid stress resistance pathways and to define the interplay between the different regulators. Results We combined mutational, phenotypic and gene expression analyses, to unravel the regulatory hierarchy in acid resistance involving H-NS, RcsB-P/GadE complex, HdfR, CadC, AdiY regulators, and DNA-binding assays to separate direct effects from indirect ones. RcsB-P/GadE regulatory complex, the general direct regulator of glutamate-, arginine- and lysine-dependent acid resistance pathways plays a central role in the regulatory cascade. However, H-NS also directly controls specific regulators of these pathways (e.g. cadC and genes involved in general stress resistance (hdeAB, hdeD, dps, adiY. Finally, we found that in addition to H-NS and RcsB, a third regulator, HdfR, inversely controls glutamate-dependent acid resistance pathway and motility. Conclusions H-NS lies near the top of the hierarchy orchestrating acid response centred on RcsB-P/GadE regulatory complex, the general direct regulator of glutamate-, arginine- and lysine-dependent acid resistance pathways.

  13. Incidence and impact on clinical outcome of infections with piperacillin/tazobactam resistant Escherichia coli in ICU: A retrospective study

    Directory of Open Access Journals (Sweden)

    Mounier Roman

    2008-05-01

    Full Text Available Abstract Background Escherichia coli infections are frequent in ICU patients. The increased resistance to fluoroquinolones and amoxicillin/clavulanate of this pathogen mandates the prescription of broad-spectrum antibiotics such as piperacillin/tazobactam (PIP-TAZ or third generation cephalosporins (3GC. Methods To assess incidence and impact on clinical outcome of infections with PIP-TAZ resistant E. coli in ICU patients, we conducted a retrospective cohort study with infections due to PIP-TAZ resistant (PIP-TAZ R or to PIP-TAZ susceptible strains (PIP-TAZ S between 1 January 2002 and 30 June 2004. Results Of 83 strains, 13 were PIP-TAZ R: 2 strains produced an extended-spectrum β-lactamase (2%, 11 produced a high level penicillinase (13%. Prior amoxicillin or amoxicillin/clavulanate prescription was reported in 7 cases (54% of infections with PIP-TAZ R isolates and in 15 cases (21% of infections with PIP-TAZ S isolates (p = 0.03. Time of onset of the infection from hospital admission was longer in case of infections with PIP-TAZ R than with PIP-TAZ S isolates (22 ± 32 vs 10 ± 21 days, p = 0.01. The overall ICU mortality rate was 38%. Mortality and length of stay in ICU were similar in case of infections with PIP-TAZ R isolates and with PIP-TAZ S isolates. Conclusion Infections with PIP-TAZ R E. coli are frequent in ICU patients. No prognostic impact of this pattern of resistance was found. Prescription of PIP-TAZ for empirical treatment of E. coli infections in ICU however exposes to inappropriate therapy.

  14. Long-Term Carriage of Ciprofloxacin-Resistant Escherichia coli Isolates in High-Risk Nursing Home Residents.

    Science.gov (United States)

    Ismail, Miriam D; Luo, Ting; McNamara, Sara; Lansing, Bonnie; Koo, Evonne; Mody, Lona; Foxman, Betsy

    2016-04-01

    BACKGROUND Rates of multidrug-resistant gram-negative organisms are surpassing those of methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci in nursing homes (NHs). OBJECTIVE To characterize the incidence and duration of carriage of ciprofloxacin-resistant Escherichia coli (CipREc) in NHs and identify those in the O25b-ST131 lineage. METHODS We collected 227 CipREc isolates obtained by routine and regular surveillance of high-risk NH residents with indwelling devices. Repetitive element palindromic (REP)-polymerase chain reaction assay and multiplex polymerase chain reaction amplification for O25b-ST131 E. coli detection were performed using (GTG)5-primers and O25pabBspe and trpA2 primer pairs, respectively. RESULTS We found a high period prevalence of CipREc colonization (21.5%), high rates of recolonization with the same strain following clearing (0.46 recolonizations/ person/ year), and an acquisition incidence of 1.05 cases/1,000 person-days. Almost three-quarters of colonized residents carried strains in the O25b-ST131 E. coli lineage. Compared with isolates not in the lineage, O25b-ST131 isolates were carried significantly longer (10 vs 3 months). We identified 18 different REP-types; 2 occurred in 55% of the residents colonized with CipREc, and in more than 1 NH. Duration of CipREc carriage varied by REP-type and averaged 6 months. CONCLUSION CipREc occurred frequently in NH residents and is carried for long durations, and reacquisition following clearance is common Trial registration. ClinicalTrials.gov identifier: NCT01062841. Infect. Control Hosp. Epidemiol. 2016;37(4):440-447. PMID:26782632

  15. MOLECULAR DETECTION OF ANTIBIOTIC-RESISTANCE DETERMINANTS IN ESCHERICHIA COLI ISOLATED FROM THE ENDANGERED AUSTRALIAN SEA LION (NEOPHOCA CINEREA).

    Science.gov (United States)

    Delport, Tiffany C; Harcourt, Robert G; Beaumont, Linda J; Webster, Koa N; Power, Michelle L

    2015-07-01

    Greater interaction between humans and wildlife populations poses significant risks of anthropogenic impact to natural ecosystems, especially in the marine environment. Understanding the spread of microorganisms at the marine interface is therefore important if we are to mitigate adverse effects on marine wildlife. We investigated the establishment of Escherichia coli in the endangered Australian sea lion (Neophoca cinerea) by comparing fecal isolation from wild and captive sea lion populations. Fecal samples were collected from wild colonies March 2009-September 2010 and from captive individuals March 2011-May 2013. Using molecular screening, we assigned a phylotype to E. coli isolates and determined the presence of integrons, mobile genetic elements that capture gene cassettes conferring resistance to antimicrobial agents common in fecal coliforms. Group B2 was the most abundant phylotype in all E. coli isolates (n = 37), with groups A, B1, and D also identified. Integrons were not observed in E. coli (n = 21) isolated from wild sea lions, but were identified in E. coli from captive animals (n = 16), from which class I integrases were detected in eight isolates. Sequencing of gene cassette arrays identified genes conferring resistance to streptomycin-spectinomycin (aadA1) and trimethoprim (dfrA17, dfrB4). Class II integrases were not detected in the E. coli isolates. The frequent detection in captive sea lions of E. coli with resistance genes commonly identified in human clinical cases suggests that conditions experienced in captivity may contribute to establishment. Identification of antibiotic resistance in the microbiota of Australian sea lions provides crucial information for disease management. Our data will inform conservation management strategies and provide a mechanism to monitor microorganism dissemination to sensitive pinniped populations. PMID:25919463

  16. Effect of liposome-entrapped ampicillin on survival of Listeria monocytogenes in murine peritoneal macrophages.

    OpenAIRE

    Bakker-Woudenberg, I A; Lokerse, A F; Vink-van den Berg, J C; Roerdink, F H; Michel, M F

    1986-01-01

    The effect of liposomal encapsulation of ampicillin on the antibacterial activity against intracellular Listeria monocytogenes was studied by comparing survival of L. monocytogenes within peritoneal mouse macrophages in the presence of free ampicillin alone or in combination with liposome-entrapped ampicillin. In the presence of 50 micrograms of free ampicillin per ml of the incubation medium, intracellular growth of L. monocytogenes was still observed, although less as compared with intracel...

  17. Modification of the rib operon derived from Bacillus subtilis and its expression in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Zhang Huitu; Meng Kun; Wang Yaru; Luo Huiying; Yuan Tiezheng; Yang Peilong; Bai Yingguo; Yao Bin; Fan Yunliu

    2007-01-01

    A riboflavin operon(rib operon)derived from Bacillus subtilis 368 was modified on structure and the resulting operons were expressed in various strains of Escherichia coli. The results showed that the optimization of the rib operon and the host strain used for expression are two main factors affecting the riboflavin production. Replacing the promoter l and rfn box of the rib operon with a strong constructive promoter spo l drastically increased the expression of the rib genes. When E. Coli JMl09 was used as the host strain, the highest riboflavin production reached 95.3μg/mL(about eight times higher than that 0f the unmodified rib operon). In addition, when tetracycline(20 μg/mL)was used as the selective pressure, compared with the ampicillin resistant transformants, a higher riboflavin yield Was obtained in tetracycline resistant host strain.

  18. Determination of antibiotic hypersensitivity among 4,000 single-gene-knockout mutants of Escherichia coli.

    Science.gov (United States)

    Tamae, Cindy; Liu, Anne; Kim, Katherine; Sitz, Daniel; Hong, Jeeyoon; Becket, Elinne; Bui, Ann; Solaimani, Parrisa; Tran, Katherine P; Yang, Hanjing; Miller, Jeffrey H

    2008-09-01

    We have tested the entire Keio collection of close to 4,000 single-gene knockouts in Escherichia coli for increased susceptibility to one of seven different antibiotics (ciprofloxacin, rifampin, vancomycin, ampicillin, sulfamethoxazole, gentamicin, or metronidazole). We used high-throughput screening of several subinhibitory concentrations of each antibiotic and reduced more than 65,000 data points to a set of 140 strains that display significantly increased sensitivities to at least one of the antibiotics, determining the MIC in each case. These data provide targets for the design of "codrugs" that can potentiate existing antibiotics. We have made a number of double mutants with greatly increased sensitivity to ciprofloxacin, and these overcome the resistance generated by certain gyrA mutations. Many of the gene knockouts in E. coli are hypersensitive to more than one antibiotic. Together, all of these data allow us to outline the cell's "intrinsic resistome," which provides innate resistance to antibiotics. PMID:18621901

  19. Dissemination of cephalosporin resistance genes between Escherichia coli strains from farm animals and humans by specific plasmid lineages.

    Directory of Open Access Journals (Sweden)

    Mark de Been

    2014-12-01

    Full Text Available Third-generation cephalosporins are a class of β-lactam antibiotics that are often used for the treatment of human infections caused by Gram-negative bacteria, especially Escherichia coli. Worryingly, the incidence of human infections caused by third-generation cephalosporin-resistant E. coli is increasing worldwide. Recent studies have suggested that these E. coli strains, and their antibiotic resistance genes, can spread from food-producing animals, via the food-chain, to humans. However, these studies used traditional typing methods, which may not have provided sufficient resolution to reliably assess the relatedness of these strains. We therefore used whole-genome sequencing (WGS to study the relatedness of cephalosporin-resistant E. coli from humans, chicken meat, poultry and pigs. One strain collection included pairs of human and poultry-associated strains that had previously been considered to be identical based on Multi-Locus Sequence Typing, plasmid typing and antibiotic resistance gene sequencing. The second collection included isolates from farmers and their pigs. WGS analysis revealed considerable heterogeneity between human and poultry-associated isolates. The most closely related pairs of strains from both sources carried 1263 Single-Nucleotide Polymorphisms (SNPs per Mbp core genome. In contrast, epidemiologically linked strains from humans and pigs differed by only 1.8 SNPs per Mbp core genome. WGS-based plasmid reconstructions revealed three distinct plasmid lineages (IncI1- and IncK-type that carried cephalosporin resistance genes of the Extended-Spectrum Beta-Lactamase (ESBL- and AmpC-types. The plasmid backbones within each lineage were virtually identical and were shared by genetically unrelated human and animal isolates. Plasmid reconstructions from short-read sequencing data were validated by long-read DNA sequencing for two strains. Our findings failed to demonstrate evidence for recent clonal transmission of

  20. Toward repurposing ciclopirox as an antibiotic against drug-resistant Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae.

    Directory of Open Access Journals (Sweden)

    Kimberly M Carlson-Banning

    Full Text Available Antibiotic-resistant infections caused by gram-negative bacteria are a major healthcare concern. Repurposing drugs circumvents the time and money limitations associated with developing new antimicrobial agents needed to combat these antibiotic-resistant infections. Here we identified the off-patent antifungal agent, ciclopirox, as a candidate to repurpose for antibiotic use. To test the efficacy of ciclopirox against antibiotic-resistant pathogens, we used a curated collection of Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae clinical isolates that are representative of known antibiotic resistance phenotypes. We found that ciclopirox, at 5-15 µg/ml concentrations, inhibited bacterial growth regardless of the antibiotic resistance status. At these same concentrations, ciclopirox reduced growth of Pseudomonas aeruginosa clinical isolates, but some of these pathogens required higher ciclopirox concentrations to completely block growth. To determine how ciclopirox inhibits bacterial growth, we performed an overexpression screen in E. coli. This screen revealed that galE, which encodes UDP-glucose 4-epimerase, rescued bacterial growth at otherwise restrictive ciclopirox concentrations. We found that ciclopirox does not inhibit epimerization of UDP-galactose by purified E. coli GalE; however, ΔgalU, ΔgalE, ΔrfaI, or ΔrfaB mutant strains all have lower ciclopirox minimum inhibitory concentrations than the parent strain. The galU, galE, rfaI, and rfaB genes all encode enzymes that use UDP-galactose or UDP-glucose for galactose metabolism and lipopolysaccharide (LPS biosynthesis. Indeed, we found that ciclopirox altered LPS composition of an E. coli clinical isolate. Taken together, our data demonstrate that ciclopirox affects galactose metabolism and LPS biosynthesis, two pathways important for bacterial growth and virulence. The lack of any reported fungal resistance to ciclopirox in over twenty years of use in the clinic

  1. Characterization of Fosfomycin Resistant Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates from Human and Pig in Taiwan.

    Directory of Open Access Journals (Sweden)

    Sung-Pin Tseng

    Full Text Available To investigate the efficacy of fosfomycin against extended-spectrum β-lactamases (ESBL producing Escherichia coli in Taiwan and the resistance mechanisms and characterization of human and pig isolates, we analyzed 145 ESBL-producing isolates collected from two hospitals (n = 123 and five farms (n = 22 in Taiwan from February to May, 2013. Antimicrobial susceptibilities were determined. Clonal relatedness was determined by PFGE and multi-locus sequence typing. ESBLs, ampC, and fosfomycin resistant genes were detected by PCR, and their flanking regions were determined by PCR mapping and sequencing. The fosfomycin resistant mechanisms, including modification of the antibiotic target (MurA, functionless transporters (GlpT and UhpT and their regulating genes such as uhpA, cyaA, and ptsI, and antibiotic inactivation by enzymes (FosA and FosC, were examined. The size and replicon type of plasmids carrying fosfomycin resistant genes were analyzed. Our results revealed the susceptibility rates of fosfomycin were 94% for human ESBL-producing E. coli isolates and 77% for pig isolates. The PFGE analysis revealed 79 pulsotypes. No pulsotype was found existing in both human and pig isolates. Three pulsotypes were distributed among isolates from two hospitals. ISEcp1 carrying blaCTX-M-group 9 was the predominant transposable elements of the ESBL genes. Among the thirteen fosfomycin resistant isolates, functionless transporters were identified in 9 isolates. Three isolates contained novel amino acid substitutions (Asn67Ile, Phe151Ser and Trp164Ser, Val146Ala and His159Tyr, respectively in MurA (the target of fosfomycin. Four isolates had fosfomycin modified enzyme (fosA3 in their plasmids. The fosA3 gene was harboured in an IncN-type plasmid (101 kbp in the three pig isolates and an IncB/O-type plasmid (113 kbp in the human isolate. In conclusion, we identified that 6% and 23% of the ESBL-producing E. coli from human and pigs were resistant to fosfomycin

  2. Multidrug Resistant CTX-M-Producing Escherichia coli: A Growing Threat among HIV Patients in India

    OpenAIRE

    Kesavaram Padmavathy; Krishnan Padma; Sikhamani Rajasekaran

    2016-01-01

    Extended Spectrum β-Lactamases (ESBLs) confer resistance to third-generation cephalosporins and CTX-M types have emerged as the most prominent ESBLs worldwide. This study was designed to determine the prevalence of CTX-M positive ESBL-producing urinary E. coli isolates from HIV patients and to establish the association of multidrug resistance, phylogeny, and virulence profile with CTX-M production. A total of 57 ESBL producers identified among 76 E. coli strains isolated from HIV patients fro...

  3. Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

    OpenAIRE

    Liu, Ping; Soupir, Michelle L; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

    2011-01-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance ...

  4. Biofilm formation by multidrug resistant Escherichia coli ST131 is dependent on type 1 fimbriae and assay conditions.

    Science.gov (United States)

    Sarkar, Sohinee; Vagenas, Dimitrios; Schembri, Mark A; Totsika, Makrina

    2016-04-01

    Escherichia coli sequence type 131 (ST131) has emerged as a pandemic lineage of important multidrug resistant pathogens worldwide. Despite many studies examining the epidemiology of ST131, only a few studies to date have investigated the capacity of ST131 strains to form biofilms. Some of these studies have reported contrasting findings, with no specific ST131 biofilm-promoting factors identified. Here, we examined a diverse collection of ST131 isolates for in vitro biofilm formation in different media and assay conditions, including urine from healthy adult women. We found significant differences among strains and assay conditions, which offers an explanation for the contrasting findings reported by previous studies using a single condition. Importantly, we showed that expression of type 1 fimbriae is a critical determinant for biofilm formation by ST131 strains and that inhibition of the FimH adhesin significantly reduces biofilm formation. We also offer direct genetic evidence for the contribution of type 1 fimbriae in biofilm formation by the reference ST131 strain EC958, a representative of the clinically dominant H30-Rx ST131 subgroup. This is the first study of ST131 biofilm formation in biologically relevant conditions and paves the way for the application of FimH inhibitors in treating drug resistant ST131 biofilm infections. PMID:26940589

  5. Potential antibacterial activity of berberine against multi drug resistant enterovirulent Escherichia coli isolated from yaks (Poephagus grunniens) with haemorrhagic diarrhoea

    Institute of Scientific and Technical Information of China (English)

    Samiran Bandyopadhyay; Debasish Bhattacharyya; Mihir Sarkar; Kishore K Baruah; Pabitra H Patra; Achintya Mahanti; Dipak K Mondal; Premanshu Dandapat; Subhasis Bandyopadhyay; Indranil Samanta; Chandan Lodh; Asit K Bera

    2013-01-01

    Objective: To evaluate the antimicrobial efficacy of berberine, a plant alkaloid. Methods: Five multi-drug resistant (MDR) STEC/EPEC and five MDR ETEC isolates from yaks with haemorrhagic diarrhoea were selected for the study. Antibacterial activity of berberine was evaluated by broth dilution and disc diffusion methods. The binding kinetics of berberine to DNA and protein was also enumerated. Results: For both categories of enterovirulent Escherichia coli (E. coli) isolates, berberine displayed the antibacterial effect in a dose dependent manner. The MIC50 of berberine chloride for STEC/EPEC isolates varied from 2.07 μM to 3.6 μM with a mean of (2.95 ± 0.33) μM where as for ETEC strains it varied from 1.75 to 1.96 μM with a mean of (1.87 ± 0.03) μM. Berberine bind more tightly with double helix DNA with Bmax and Kd of (24.68±2.62) and (357.8± 57.8), respectively. Berberine reacted with protein in comparatively loose manner with Bmax and Kd of (18.9±3.83) and (286.2±113.6), respectively. Conclusions: The results indicate clearly that berberine may serve as a good antibacterial against multi drug resistant E. coli.

  6. The effect of growth conditions on inducible, recA-dependent resistance to X rays in Escherichia coli

    International Nuclear Information System (INIS)

    Escherichia coli cells grown to logarithmic phase in, and plated on, rich medium (yeast extract-nutrient broth) were more resistant to X rays, ultraviolet (uv) radiation, and methyl methanesulfonate (MMS) than cells grown in, and plated on, minimal medium. We have called this enhanced survival capability medium-dependent resistance (MDR). The magnitude of MDR observed after oxic X irradiation was greater than that observed after anoxic X irradiation, uv irradiation, or MMS treatment. MDR was not observed in stationary-phase cells with X or uv radiation. MDR was associated with an increased ability to repair X-ray-induced DNA single-strand breaks, and with reduced X-ray-induced DNA degradation and protein synthesis retardation. Postirradiation protein synthesis was concluded to be critical in allowing the high X-ray survival associated with MDR, because of the large radiosensitization caused by a postirradiation growth medium shift down or treatment with rifampicin (RIF), recA protein must be at least one of the proteins whose synthesis is critical to MDR, as judged by the absence of MDR or a RIF effect in X-irradiated recA and lexA mutants. The results with X-irradiated temperature-conditional recA cells suggest that it is only after cells have been damaged that the recA gene plays a role in MDR

  7. The effect of growth conditions on inducible, recA-dependent resistance to x rays in Escherichia coli

    International Nuclear Information System (INIS)

    Escherichia coli cells grown to logarithmic phase in, and plated on, rich medium (yeast extract-nutrient broth) were more resistant to X rays, ultraviolet (uv) radiation, and methyl methanesulfonate (MMS) than cells grown in, and plated on, minimal medium. We have called this enhanced survival capability medium-dependent resistance (MDR). The magnitude of MDR observed after oxic X irradiation was greater than that observed after anoxic X irradiation, uv irradiation, or MMS treatment. MDR was not observed in stationary-phase cells with X or uv radiation. MDR was associated with an increased ability to repair X-ray-induced DNA single-strand breaks, and with reduced X-ray-induced DNA degradation and protein synthesis retardation. Postirradiation protein synthesis was concluded to be critical in allowing the high X-ray survival associated with MDR, because of the large radiosensitization caused by a postirradiation growth medium shift down or treatment with rifampicin (RIF). recA protein must be at least one of the proteins whose synthesis is critical to MDR, as judged by the absence of MDR or a RIF effect in X-irradiated recA and lexA mutants. The results with X-irradiated temperature-conditional recA cells suggest that it is only after cells have been damaged that the recA gene plays a role in MDR

  8. Antibacterial activity of herbal extracts against multi-drug resistant Escherichia coli recovered from retail chicken meat.

    Science.gov (United States)

    Shaheen, Arfat Yousaf; Sheikh, Ali Ahmad; Rabbani, Masood; Aslam, Asim; Bibi, Tasra; Liaqat, Fakhra; Muhammad, Javed; Rehmani, Shafqat Fatima

    2015-07-01

    Increasing incidence rate of multiple drug resistance in Escherichia coli (E. coli) due to extensive uses of antibiotics is a serious challenge to disease treatment. Contaminated retail chicken meat is one of the major sources of spread of multi drug resistant (MDR) E. coli. Current study has been conducted to study the prevalence of MDR E. coli in retail chicken meat samples from Lahore city of Pakistan and it was found that 73.86% of E. coli isolates have MDR pattern. In vitro evaluation of antibacterial activity of crude ethanolic extracts of six herbs against MDR E. coli phenotypes has revealed that clove and cinnamon have maximum zones of inhibition as compared to other herbal extracts. Mint and coriander gave the intermediate results while garlic and kalonji showed the least antibacterial activity against the MDR E. coli phenotypes using the agar well diffusion technique. Average Minimum Inhibitory Concentrations (MICs) for clove, mint, cinnamon, coriander, kalonji and garlic extracts were 1.15, 1.38, 0.5, 1.99, 2.41, 8.60 mg/mL respectively using the broth micro dilution method. The results obtained in present study were revealed that crude ethanol extracts of selected herbs have had significant antibacterial activity. Hence they can be used as promising alternatives of antimicrobials against MDR E. coli species and can be used for cooked food preservation. PMID:26142503

  9. Simplified process for ethanol production from sugarcane bagasse using hydrolysate-resistant Escherichia coli strain MM160.

    Science.gov (United States)

    Geddes, C C; Mullinnix, M T; Nieves, I U; Peterson, J J; Hoffman, R W; York, S W; Yomano, L P; Miller, E N; Shanmugam, K T; Ingram, L O

    2011-02-01

    Hexose and pentose sugars from phosphoric acid pretreated sugarcane bagasse were co-fermented to ethanol in a single vessel (SScF), eliminating process steps for solid-liquid separation and sugar cleanup. An initial liquefaction step (L) with cellulase was included to improve mixing and saccharification (L+SScF), analogous to a corn ethanol process. Fermentation was enabled by the development of a hydrolysate-resistant mutant of Escherichia coli LY180, designated MM160. Strain MM160 was more resistant than the parent to inhibitors (furfural, 5-hydroxymethylfurfural, and acetate) formed during pretreatment. Bagasse slurries containing 10% and 14% dry weight (fiber plus solubles) were tested using pretreatment temperatures of 160-190°C (1% phosphoric acid, 10 min). Enzymatic saccharification and inhibitor production both increased with pretreatment temperature. The highest titer (30 g/L ethanol) and yield (0.21 g ethanol/g bagasse dry weight) were obtained after incubation for 122 h using 14% dry weight slurries of pretreated bagasse (180°C). PMID:21111615

  10. Extended-spectrum beta-lactamases in ceftazidime-resistant Escherichia coli and Klebsiella pneumoniae isolates in Turkish hospitals

    Directory of Open Access Journals (Sweden)

    Hosoglu S

    2007-01-01

    Full Text Available Purpose: To study the prevalence of TEM-, SHV- and GES-type β -lactamases among Escherichia coli and Klebsiella pneumoniae strains having ceftazidime MICs higher than 2 mg/L. Methods: A total of 63 E. coli and 41 K. pneumoniae isolated from five different university hospitals were studied for the existence of TEM-, SHV- and GES-type β -lactamases. Susceptibility tests were carried out according to the criteria of National Committee for Clinical Laboratory Standards. MICs were obtained by agar dilution method. Existence of extended-spectrum β -lactamases (ESBLs were assessed by double-disc synergy test (DDST. Existence of the above-mentioned β -lactamase genes were studied both by PCR with specific oligonucleotide primers and isoelectric focusing methods. Results: None of the isolates were carbapenem-resistant. DDSTs were positive in 50 (79.3% and 33 (80.5% of E. coli and K. pneumoniae , respectively. TEM gene was detected in 41 (65.1% and 19 (46.3%, whereas SHV gene in 18 (28.6% and 20 (48.8% of E. coli and K. pneumoniae strains, respectively. GES genes were not detected. Conclusions: TEM and SHV genes are highly prevalent among ESBL-producing E. coli and K. pneumoniae , whereas GES-type ESBLs are absent and found not to be responsible of ceftazidime resistance in Turkish hospitals.

  11. Antimicrobial resistance testing of verocytotoxin-producing Escherichia coli and first description of TEM-52 extended-spectrum {beta}-lactamase in serogroup O26.

    OpenAIRE

    Buvens, Glenn; Bogaerts, Pierre; Glupczynski, Gerald; Lauwers, Sabine; Piérard, Denis

    2010-01-01

    We have investigated the antimicrobial resistance of verocytotoxin-producing Escherichia coli (VTEC) strains isolated from humans, animals, food and environment in Belgium. Resistance was more frequent in human non-O157 as compared to O157 strains from humans or other sources and within non-O157 VTEC, intimin-positive strains were more resistant than intimin-negative strains. We also report the first VTEC producing an IncI1 plasmid-borne blaTEM-52 extended-spectrum beta-lactamase previously a...

  12. Antimicrobial Resistance Testing of Verocytotoxin-Producing Escherichia coli and First Description of TEM-52 Extended-Spectrum β-Lactamase in Serogroup O26 ▿

    OpenAIRE

    Buvens, Glenn; Bogaerts, Pierre; Glupczynski, Youri; Lauwers, Sabine; Piérard, Denis

    2010-01-01

    We have investigated the antimicrobial resistance of verocytotoxin-producing Escherichia coli (VTEC) strains isolated from humans, animals, food, and the environment in Belgium. Resistance was more frequent in non-O157 strains from humans than in O157 strains from humans or other sources, and among non-O157 VTEC strains, intimin-positive strains were more resistant than intimin-negative strains. We also report the first VTEC strain producing an IncI1 extended-spectrum β-lactamase encoded by p...

  13. Fluoroquinolone resistance mechanisms in urinary tract pathogenic Escherichia coli isolated during rapidly increasing fluoroquinolone consumption in a low-use country

    DEFF Research Database (Denmark)

    Christiansen, Nina; Nielsen, Lene; Jakobsen, Lotte;

    2011-01-01

    Resistance to ciprofloxacin in Escherichia coli from urinary tract infections (UTI) in Denmark is increasing parallel to increased use of fluoroquinolones both in Denmark and in other European countries. The objective was to investigate the occurrence of ciprofloxacin resistance mechanisms......(6')-Ib-cr gene was detected on plasmids from five isolates showing ciprofloxacin MICs >512 mg/L. No overall clonal relationship among isolates was found according to PFGE. Target modification is the dominating fluoroquinolone resistance mechanism often found in combination with efflux and sometimes...

  14. Oxazolidinone resistance mutations in 23S rRNA of Escherichia coli reveal the central region of domain V as the primary site of drug action

    DEFF Research Database (Denmark)

    Xiong, L; Kloss, P; Douthwaite, S; Andersen, N M; Swaney, S; Shinabarger, D L; Mankin, A S

    2000-01-01

    resistance mutations were clustered in the vicinity of the central loop of domain V of 23S rRNA, suggesting that this rRNA region plays a major role in the interaction of the drug with the ribosome. Although the central loop of domain V is an essential integral component of the ribosomal peptidyl transferase......, we selected Escherichia coli oxazolidinone-resistant mutants, which contained a randomly mutagenized plasmid-borne rRNA operon. The same mutation, G2032 to A, was identified in the 23S rRNA genes of several independent resistant isolates. Engineering of this mutation by site-directed mutagenesis in...... the wild-type rRNA operon produced an oxazolidinone resistance phenotype, establishing that the G2032A substitution was the determinant of resistance. Engineered U and C substitutions at G2032, as well as a G2447-to-U mutation, also conferred resistance to oxazolidinone. All the characterized...

  15. Multidrug Resistant CTX-M-Producing Escherichia coli: A Growing Threat among HIV Patients in India

    Directory of Open Access Journals (Sweden)

    Kesavaram Padmavathy

    2016-01-01

    Full Text Available Extended Spectrum β-Lactamases (ESBLs confer resistance to third-generation cephalosporins and CTX-M types have emerged as the most prominent ESBLs worldwide. This study was designed to determine the prevalence of CTX-M positive ESBL-producing urinary E. coli isolates from HIV patients and to establish the association of multidrug resistance, phylogeny, and virulence profile with CTX-M production. A total of 57 ESBL producers identified among 76 E. coli strains isolated from HIV patients from South India were screened for blaCTX-M, AmpC production, multidrug resistance, and nine virulence associated genes (VAGs, fimH, pap, afa/dra, sfa/foc, iutA, fyuA, iroN, usp, and kpsMII. The majority (70.2% of the ESBL producers harbored blaCTX-M and were AmpC coproducers. Among the CTX-M producers, 47.5% were found to be UPEC, 10% harbored as many as 7 VAGs, and 45% possessed kpsMII. Multidrug resistance (CIPRSXTRGENR was significantly more common among the CTX-M producers compared to the nonproducers (70% versus 41.2%. However, 71.4% of the multidrug resistant CTX-M producers exhibited susceptibility to nitrofurantoin thereby making it an effective alternative to cephalosporins/fluoroquinolones. The emergence of CTX-M-producing highly virulent, multidrug resistant uropathogenic E. coli is of significant public health concern in countries like India with a high burden of HIV/AIDS.

  16. Multidrug Resistant CTX-M-Producing Escherichia coli: A Growing Threat among HIV Patients in India.

    Science.gov (United States)

    Padmavathy, Kesavaram; Padma, Krishnan; Rajasekaran, Sikhamani

    2016-01-01

    Extended Spectrum β-Lactamases (ESBLs) confer resistance to third-generation cephalosporins and CTX-M types have emerged as the most prominent ESBLs worldwide. This study was designed to determine the prevalence of CTX-M positive ESBL-producing urinary E. coli isolates from HIV patients and to establish the association of multidrug resistance, phylogeny, and virulence profile with CTX-M production. A total of 57 ESBL producers identified among 76 E. coli strains isolated from HIV patients from South India were screened for bla CTX-M, AmpC production, multidrug resistance, and nine virulence associated genes (VAGs), fimH, pap, afa/dra, sfa/foc, iutA, fyuA, iroN, usp, and kpsMII. The majority (70.2%) of the ESBL producers harbored bla CTX-M and were AmpC coproducers. Among the CTX-M producers, 47.5% were found to be UPEC, 10% harbored as many as 7 VAGs, and 45% possessed kpsMII. Multidrug resistance (CIP(R)SXT(R)GEN(R)) was significantly more common among the CTX-M producers compared to the nonproducers (70% versus 41.2%). However, 71.4% of the multidrug resistant CTX-M producers exhibited susceptibility to nitrofurantoin thereby making it an effective alternative to cephalosporins/fluoroquinolones. The emergence of CTX-M-producing highly virulent, multidrug resistant uropathogenic E. coli is of significant public health concern in countries like India with a high burden of HIV/AIDS. PMID:27123344

  17. Multidrug Resistant CTX-M-Producing Escherichia coli: A Growing Threat among HIV Patients in India

    Science.gov (United States)

    Padmavathy, Kesavaram; Padma, Krishnan; Rajasekaran, Sikhamani

    2016-01-01

    Extended Spectrum β-Lactamases (ESBLs) confer resistance to third-generation cephalosporins and CTX-M types have emerged as the most prominent ESBLs worldwide. This study was designed to determine the prevalence of CTX-M positive ESBL-producing urinary E. coli isolates from HIV patients and to establish the association of multidrug resistance, phylogeny, and virulence profile with CTX-M production. A total of 57 ESBL producers identified among 76 E. coli strains isolated from HIV patients from South India were screened for blaCTX-M, AmpC production, multidrug resistance, and nine virulence associated genes (VAGs), fimH, pap, afa/dra, sfa/foc, iutA, fyuA, iroN, usp, and kpsMII. The majority (70.2%) of the ESBL producers harbored blaCTX-M and were AmpC coproducers. Among the CTX-M producers, 47.5% were found to be UPEC, 10% harbored as many as 7 VAGs, and 45% possessed kpsMII. Multidrug resistance (CIPRSXTRGENR) was significantly more common among the CTX-M producers compared to the nonproducers (70% versus 41.2%). However, 71.4% of the multidrug resistant CTX-M producers exhibited susceptibility to nitrofurantoin thereby making it an effective alternative to cephalosporins/fluoroquinolones. The emergence of CTX-M-producing highly virulent, multidrug resistant uropathogenic E. coli is of significant public health concern in countries like India with a high burden of HIV/AIDS. PMID:27123344

  18. Detection of Class 1 and 2 Integrons, β-Lactamase Genes and Molecular Characterization of Sulfonamide Resistance in Escherichia coli Isolates Recovered from Poultry in China

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    Jam Kashif§, Rehana Buriro§, Javed Memon, Muhammad Yaqoob, Jamila Soomro§, Diao Dongxue, Huang Jinhu and Wang Liping*

    2013-07-01

    Full Text Available This study aimed to detect integrons, β-lactamase genes and to characterize sulfonamide resistant E. coli isolates recovered from poultry. All the isolates (n=38 were investigated for the presence of integrons, Sul1, Sul2, Sul3 genes by PCR. Class 1 and class 2 integron were present in 79 and 16%, respectively. Additional resistance gene cassette embedded in class 1 and 2 integrons was aadA1, aadA5, dfrA17 and aadA22, dfrA, respectively. Sul1 and Sul2 genes were detected in 42.1 and 60.5% isolates, respectively. Both the Sul1 and Sul2 were present in 23% isolates. However, Sul3 gene was not present. Co-existence of Sul1 and Sul2 with class 1 integrons was found in 28.9 and 60.5% of class 1 integron positive isolates, respectively. Whereas, a less percentage of isolates showed a low level of resistance to β-lactams and no blaCTX-M, blaSHV and blaTEM was found. The MIC results showed resistance to sulfadiazine and sulfamethoxazole-trimethoprim in 88 and 84% isolates, resistance to penicillin, ampicillin, amoxicillin was 52, 52 and 44%, respectively. Chloramphenicol, florfenicol, tetracycline and gentamycin resistance was found in 51, 5, 42 and 67% isolates, respectively. This study revealed high frequency of class 1 integrons, Sul genes among poultry E. coli isolates, therefore further spread of Sul genes and integrons is predictable.

  19. Influence of therapeutic ceftiofur treatments of feedlot cattle on fecal and hide prevalences of commensal Escherichia coli resistant to expanded-spectrum cephalosporins, and molecular characterization of resistant isolates

    Science.gov (United States)

    In the United States the bla**CMY-2** gene contained within incompatibility type A/C (IncA/C) plasmids is frequently identified in extended-spectrum cephalosporin-resistant Escherichia coli (ESCr) from both human and cattle sources. Concerns have been raised that therapeutic use of ceftiofur in catt...

  20. Multidrug resistant AmpC β-lactamase producing Escherichia coli isolated from a paediatric hospital

    OpenAIRE

    Jameel, Noor-ul-Ain; Ejaz, Hasan; Zafar, Aizza; Amin, Hafsa

    2014-01-01

    Objective : The objective of the study was to observe the antimicrobial resistance of AmpC β-lactamase producing E. coli. Methods: Six hundred and seventy E. coli were isolated from 20,257 various pathological samples collected from The Children’s Hospital and Institute of Child Health, Lahore, Pakistan. The isolates showed resistance to ceftazidime which were further examined for AmpC β-lactamase activity by Disc Potentiation method. Results: There were 670 isolates of E. coli out of which 8...

  1. Antibacterial agents and heavy metal resistance in Gram-negative bacteria isolated from seawater, shrimp and sediment in Iskenderun Bay, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Matyar, Fatih [Cukurova University, Faculty of Education, Department of Science and Technology Education, 01330 Balcali, Adana (Turkey)], E-mail: fmatyar@cu.edu.tr; Kaya, Aysenur; Dincer, Sadik [Cukurova University, Faculty of Science and Letters, Department of Biology, 01330 Balcali, Adana (Turkey)

    2008-12-15

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from seawater, sediment and shrimps, and to determine if there is a relationship between antibiotic and heavy metal resistance. We undertook studies in 2007 in the industrially polluted Iskenderun Bay, on the south coast of Turkey. The resistance of 236 Gram-negative bacterial isolates (49 from seawater, 90 from sediment and 97 from shrimp) to 16 different antibiotics, and to 5 heavy metals, was investigated by agar diffusion and agar dilution methods, respectively. A total of 31 species of bacteria were isolated: the most common strains isolated from all samples were Escherichia coli (11.4%), Aeromonas hydrophila (9.7%) and Stenotrophomonas maltophilia (9.3%). There was a high incidence of resistance to ampicillin (93.2%), streptomycin (90.2%) and cefazolin (81.3%), and a low incidence of resistance to imipenem (16.5%), meropenem (13.9%) and cefepime (8.0%). Some 56.8% of all bacteria isolated from seawater, sediment and shrimp were resistant to 7 or more antibiotics. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from 12.5 {mu}g/ml to > 3200 {mu}g/ml. The bacteria from seawater, sediment and shrimp showed high resistance to cadmium of 69.4%, 88.9%, and 81.1% respectively, and low resistance to manganese of 2%, 6.7% and 11.3% respectively. The seawater and sediment isolates which were metal resistant also showed a high resistance to three antibiotics: streptomycin, ampicillin and trimethoprim-sulphamethoxazole. In contrast, the shrimp isolates which were metal resistant were resistant to four antibiotics: cefazolin, nitrofurantoin, cefuroxime and ampicillin. Our results show that Iskenderun Bay has a significant proportion of antibiotic and heavy metal resistant Gram-negative bacteria, and these bacteria constitute a potential risk for

  2. Antibacterial agents and heavy metal resistance in Gram-negative bacteria isolated from seawater, shrimp and sediment in Iskenderun Bay, Turkey

    International Nuclear Information System (INIS)

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from seawater, sediment and shrimps, and to determine if there is a relationship between antibiotic and heavy metal resistance. We undertook studies in 2007 in the industrially polluted Iskenderun Bay, on the south coast of Turkey. The resistance of 236 Gram-negative bacterial isolates (49 from seawater, 90 from sediment and 97 from shrimp) to 16 different antibiotics, and to 5 heavy metals, was investigated by agar diffusion and agar dilution methods, respectively. A total of 31 species of bacteria were isolated: the most common strains isolated from all samples were Escherichia coli (11.4%), Aeromonas hydrophila (9.7%) and Stenotrophomonas maltophilia (9.3%). There was a high incidence of resistance to ampicillin (93.2%), streptomycin (90.2%) and cefazolin (81.3%), and a low incidence of resistance to imipenem (16.5%), meropenem (13.9%) and cefepime (8.0%). Some 56.8% of all bacteria isolated from seawater, sediment and shrimp were resistant to 7 or more antibiotics. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from 12.5 μg/ml to > 3200 μg/ml. The bacteria from seawater, sediment and shrimp showed high resistance to cadmium of 69.4%, 88.9%, and 81.1% respectively, and low resistance to manganese of 2%, 6.7% and 11.3% respectively. The seawater and sediment isolates which were metal resistant also showed a high resistance to three antibiotics: streptomycin, ampicillin and trimethoprim-sulphamethoxazole. In contrast, the shrimp isolates which were metal resistant were resistant to four antibiotics: cefazolin, nitrofurantoin, cefuroxime and ampicillin. Our results show that Iskenderun Bay has a significant proportion of antibiotic and heavy metal resistant Gram-negative bacteria, and these bacteria constitute a potential risk for public

  3. Celulitis in Japanese Quails (coturnix coturnix japonica) for Eschorichia coli: virulence factors, sensibility and profile antimicrobial resistance /
    Celulite em codornas (coturnix coturnix japonica) causada por Escherichia coli: fatores de virulência, sensibilidade e perfil de resistência antimicrobiana

    OpenAIRE

    Marilda Carlos Vidotto; Ivens Gomes Guimarães; Claudia Yurika Tamehiro; Benito Guimarães de Brito

    2000-01-01

    Ten E. coli strains isolated from celulitis lesion s of Japanese quails were to evaluated antimicrobia l resistance to twent y six drugs , to pathogenicity of strains in SPF chickens embryonated eggs and virulence factors. The antimicrobials of higher efficiency wer e ampicillin, florfenicol and the lesser efficiency were erythromycin, oxacilin, lincomicin, novobiocin, penicillin, sulfonamidas, trimethoprim+sulfomethoxazo/e and tetracyicline. The majority of E. coli strains were serum resista...

  4. A role for Lon protease in the control of the acid resistance genes of Escherichia coli.

    Science.gov (United States)

    Heuveling, Johanna; Possling, Alexandra; Hengge, Regine

    2008-07-01

    Lon protease is a major protease in cellular protein quality control, but also plays an important regulatory role by degrading various naturally unstable regulators. Here, we traced additional such regulators by identifying regulons with co-ordinately altered expression in a lon mutant by genome-wide transcriptional profiling. Besides many members of the RcsA regulon (which validates our approach as RcsA is a known Lon substrate), many genes of the sigmaS-dependent general stress response were upregulated in the lon mutant. However, the lon mutation did not affect sigmaS levels nor sigmaS activity in general, suggesting specific effects of Lon on secondary regulators involved in the control of subsets of sigmaS-controlled genes. Lon-affected genes also included the major acid resistance genes (gadA, gadBC, gadE, hdeAB and hdeD), which led to the discovery that the essential acid resistance regulator GadE (whose expression is sigmaS-controlled) is degraded in vivo in a Lon-dependent manner. GadE proteolysis is constitutive as it was observed even under conditions that induce the system (i.e. at low pH or during entry into stationary phase). GadE degradation was found to rapidly terminate the acid resistance response upon shift back to neutral pH and to avoid overexpression of acid resistance genes in stationary phase. PMID:18630346

  5. Comparison of antimicrobial resistance determinants among Salmonella, Campylobacter, Escherichia coli, and Enterococcus isolated from Swine

    Science.gov (United States)

    Introduction: The importance of Salmonella, Campylobacter, E.coli, and Enterococcus as carriers of antimicrobial resistance is well known, but limited work has been done to examine the relationship between this phenotypic characteristic and genotypic attributes among strains isolated in similar set...

  6. Determination of flavonoids in Triticum aestivum L. treated with ampicillin

    Science.gov (United States)

    Soran, M. L.; Opriş, O.; Copaciu, F.; Varodi, C.

    2012-02-01

    Pharmaceutical residues in the environment, and their potential toxic effects, have been recognized as one of the emerging research area in the environmental chemistry. Antibiotics can reach plants from treated soil or due to irrigation. The flavonoids extraction from Triticum aestivum L. treated with ampicillin and separation of flavonoids are presented in this study. There were used classical and modern extraction techniques (maceration, microwave assisted solvents, etc). The efficiency of extraction process was spectrophotometricaly evaluated by determining the total flavonoids content and by HPTLC on silica gel plates using the mixture: carbon tetrachloride - acetone - formic acid (35:11:3, v/v) as mobile phase. The developed plates were inspected both in ultraviolet and visible after visualization with NTS reagent (diphenylboryloxyethylamin). The chromatographic plates were compared in respect to determine the changes in extract composition due to the different extraction techniques. Depending on the concentration of ampicillin administered to plants, comparative studies on flavonoids content were performed.

  7. Evaluation of hard gelatin capsules and hydroxypropyl methylcellulose containing ampicillin

    Directory of Open Access Journals (Sweden)

    Graziella Gonçalves Weigert

    2012-01-01

    Full Text Available This study aims to develop and evaluate formulations containing ampicillin in capsules of gelatin and hydroxypropyl methylcellulose (HPMC. Two formulations (A and B were developed. The final product quality was evaluated by testing for quality control and the results were in agreement with the Brazilian Pharmacopoeia. The formulations with HPMC capsules showed lower percentages of drug dissolved (99.67%, HPMC-A and 87.70%, HPMC-B than the gelatin (100.18%, GEL-A and 101.16% GEL-B. Because of the delay of the ampicillin release observed in the dissolution profiles, it becomes necessary to evaluate the drugs that can be conditioned in the HPMC capsules.

  8. Intravenous ampicillin pharmacokinetics in the third trimester of pregnancy.

    Science.gov (United States)

    Kubacka, R T; Johnstone, H E; Tan, H S; Reeme, P D; Myre, S A

    1983-01-01

    The pharmacokinetics of a single dose of intravenous ampicillin were studied in nine patients during their third trimester of pregnancy. Each volunteer was given either 500 mg (5.7-8.8 mg/kg) or 1 g (15.4-21.4 mg/kg) of sodium ampicillin by rapid infusion. Postinfusion plasma concentration-time curves followed biexponential decay in all subjects. Calculated parameters included a mean plasma distribution volume of 177.1 +/- 97.5 ml/kg, tissue or peripheral distribution volume of 246.2 +/- 143.9 ml/kg, elimination half-life of 1.60 +/- 0.51 h, and total body clearance of 4.59 +/- 1.48 ml/min/kg. Dose-dependent disposition was not observed. Gestation-specific drug therapy research during pregnancy is discussed. PMID:6845399

  9. Neodymium(III) complexing with ampicillin, amoxicillin, and cephalexin

    International Nuclear Information System (INIS)

    The interaction of Nd3+ ions with ampicillin, amoxicillin, and cephalexin anions (L) in aqueous solution at 20 deg C and ionic strength of 0.1 (KNO3) was studied by pH titration. The NdL and Nd(OH)L complexes are formed in a weak alkaline solution. The distribution curves of neodymium(III) complex species depending on pH were constructed. The formation constants of the complexes were determined

  10. Categorization of the main descriptors of different ampicillin crystal habits

    OpenAIRE

    Oscar Flórez-Acosta; Gloria Tobón-Zapata; Jaime Valencia-Velasquez

    2010-01-01

    With the purpose of enabling the analysis by digital methods of particles of multisource pharmaceutical raw materials, this study analyzed different crystal habits of ampicillin particles, by grouping the external shapes obtained from 3 different solvents (acetonitrile, ethanol, and methanol), thereby reducing the number of descriptors necessary to adequately represent each shape. For this purpose, a selection of morphological descriptors was used including: circularity, roughness, roundness,...

  11. Virulence characteristics and genetic affinities of multiple drug resistant uropathogenic Escherichia coli from a semi urban locality in India.

    Directory of Open Access Journals (Sweden)

    Savita Jadhav

    Full Text Available Extraintestinal pathogenic Escherichia coli (ExPEC are of significant health concern. The emergence of drug resistant E. coli with high virulence potential is alarming. Lack of sufficient data on transmission dynamics, virulence spectrum and antimicrobial resistance of certain pathogens such as the uropathogenic E. coli (UPEC from countries with high infection burden, such as India, hinders the infection control and management efforts. In this study, we extensively genotyped and phenotyped a collection of 150 UPEC obtained from patients belonging to a semi-urban, industrialized setting near Pune, India. The isolates representing different clinical categories were analyzed in comparison with 50 commensal E. coli isolates from India as well as 50 ExPEC strains from Germany. Virulent strains were identified based on hemolysis, haemagglutination, cell surface hydrophobicity, serum bactericidal activity as well as with the help of O serotyping. We generated antimicrobial resistance profiles for all the clinical isolates and carried out phylogenetic analysis based on repetitive extragenic palindromic (rep-PCR. E. coli from urinary tract infection cases expressed higher percentages of type I (45% and P fimbriae (40% when compared to fecal isolates (25% and 8% respectively. Hemolytic group comprised of 60% of UPEC and only 2% of E. coli from feces. Additionally, we found that serum resistance and cell surface hydrophobicity were not significantly (p = 0.16/p = 0.51 associated with UPEC from clinical cases. Moreover, clinical isolates exhibited highest resistance against amoxicillin (67.3% and least against nitrofurantoin (57.3%. We also observed that 31.3% of UPEC were extended-spectrum beta-lactamase (ESBL producers belonging to serotype O25, of which four were also positive for O25b subgroup that is linked to B2-O25b-ST131-CTX-M-15 virulent/multiresistant type. Furthermore, isolates from India and Germany (as well as global sources were found to be

  12. Prevalence of blaCTX-M gene in multi-resistant Escherichia coli isolated from Urinary Tract Infections, Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Mehdi Goudarzi

    2014-11-01

    Full Text Available Background:The emergence and increase in the incidence of Extended-spectrum beta lactamase (ESBL producing Escherichia coli has become an emerging challenge especially in hospitalized patients with UTI. The aim of the present study was to survey the frequency of bla CTX-M genotype in ESBL producing E. coli isolated from hospitalized patients with UTI and determination of their antibiotic resistance pattern.Material and methodsA total of 135 E. coli isolates were collected from isolated from patients with UTI. The isolates were subjected to confirmatory phenotype tests for the presence of ESBL. 75 E. coli isolates were confirmed as ESBL-positive by means of the Double disc synergy test. In vitro susceptibility of ESBL isolates to 15 antimicrobial agents amoxicillin, penicillin, ceftazidime, cefotaxime, cefoxitin, ceftriaxone, cefixime, cephalexin, co-trimoxazole, gentamicin, nalidixic acid, ciprofloxacin, nitrofourantoin, amikacin and imipenem was performed by Kirby-Bauer’s Disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI, 2012 guideline. PCR method was used to identify bla CTX-M gene in 75 ESBL positive strains.Results:PCR and sequence analysis showed that 75 (55.5% isolates produced bla CTX-M genes. In vitro susceptibility of ESBL producing E. coli showed that all of them were resistant to amoxicillin and penicillin and The rates of resistance to the majority of tested antibiotics varied between 61% to 100 %, with the exception of amikacin (14.7% and imipenem (2.7%. Our results showed that the frequency of bla CTX-M was strikingly high (93.3%.Conclusion:These data confirmed that the frequency of bla CTX-M genes were high among E. coli isolated from patients with UTI. The trend of multidrug-resistant profile has been associated with bla CTX-M gene is alarming. Therefore, it is very important to establish a routine screening of ESBL in clinical isolates to prevent dissemination of resistant isolates in health

  13. The Kinetics of Ampicillin Release from Hydroxyapatite for Bones Regeneration

    Directory of Open Access Journals (Sweden)

    Giovanilton Ferreira da Silva

    2009-01-01

    Full Text Available Semisynthetic beta-lactam antibiotics are among the most used pharmaceuticals. Their use in veterinary and human medicine is in continuous expansion. There is a growing need for developing bioactive implants. Advantages of implantable drug delivery tools can include high release efficiency, precise dose control, low toxicity, and allow to overcome disadvantages connected with conventional methods. In this respect, hydroxyapatite (HA is an elective material. It enables to produce architectures similar to those of real bones. Here we studied a kinetic model to describe ampicillin release from HA. In the course of adsorption experiment, ampicillin was dissolved, maintained at 30∘C and shaken at 60 strokes/minute. Samples were withdrawn periodically for analysis and then returned to the mixture. Adsorbed amounts were measured by the difference of the concentration of the antibiotics before and after adsorption using UV adsorption at 225 nm. The aim of this work was to evaluate its application as ampicillin delivery carrier.

  14. Resistência a antibióticos em isolados de Escherichia coli de diferentes fontes

    OpenAIRE

    Alves, Marta Salgueiro

    2013-01-01

    A descoberta e produção de antibióticos foi um grande avanço para a medicina na primeira metade do século passado. No entanto, as bactérias adaptaram-se rapidamente desenvolvendo mecanismos de resistência aos antibióticos cuja disseminação é facilitada pela transferência horizontal de genes. Hoje em dia a resistência a antibióticos constitui um problema de saúde pública sendo detectada não só a nível clínico, mas também em ambientes naturais, com particular destaque para os ...

  15. Stability in Escherichia coli of an antibiotic resistance plasmid from Bacteroides fragilis.

    OpenAIRE

    Rashtchian, A; Booth, S J

    1981-01-01

    A Bacteroides fragilis strain resistant to penicillin G, tetracycline, and clindamycin was screened for the presence of plasmid deoxyribonucleic acid (DNA). Agarose gel electrophoresis of ethanol-precipitated DNA from cleared lysates of this strain revealed two plasmid DNA bands. The molecular weights of the plasmids were estimated by their relative mobility in agarose gel and compared with standard plasmids with known molecular weights. The molecular weights were 3.40 +/- 0.20 x 10(6) and 1....

  16. Human Intestinal Cells Modulate Conjugational Transfer of Multidrug Resistance Plasmids between Clinical Escherichia coli Isolates

    OpenAIRE

    Machado, Ana Manuel; SOMMER, Morten

    2014-01-01

    Bacterial conjugation in the human gut microbiota is believed to play a major role in the dissemination of antibiotic resistance genes and virulence plasmids. However, the modulation of bacterial conjugation by the human host remains poorly understood and there is a need for controlled systems to study this process. We established an in vitro co-culture system to study the interaction between human intestinal cells and bacteria. We show that the conjugation efficiency of a plasmid encoding an...

  17. Mortality and hospital stay associated with resistant Staphylococcus aureus and Escherichia coli bacteremia: estimating the burden of antibiotic resistance in Europe.

    Directory of Open Access Journals (Sweden)

    Marlieke E A de Kraker

    2011-10-01

    Full Text Available BACKGROUND: The relative importance of human diseases is conventionally assessed by cause-specific mortality, morbidity, and economic impact. Current estimates for infections caused by antibiotic-resistant bacteria are not sufficiently supported by quantitative empirical data. This study determined the excess number of deaths, bed-days, and hospital costs associated with blood stream infections (BSIs caused by methicillin-resistant Staphylococcus aureus (MRSA and third-generation cephalosporin-resistant Escherichia coli (G3CREC in 31 countries that participated in the European Antimicrobial Resistance Surveillance System (EARSS. METHODS AND FINDINGS: The number of BSIs caused by MRSA and G3CREC was extrapolated from EARSS prevalence data and national health care statistics. Prospective cohort studies, carried out in hospitals participating in EARSS in 2007, provided the parameters for estimating the excess 30-d mortality and hospital stay associated with BSIs caused by either MRSA or G3CREC. Hospital expenditure was derived from a publicly available cost model. Trends established by EARSS were used to determine the trajectories for MRSA and G3CREC prevalence until 2015. In 2007, 27,711 episodes of MRSA BSIs were associated with 5,503 excess deaths and 255,683 excess hospital days in the participating countries, whereas 15,183 episodes of G3CREC BSIs were associated with 2,712 excess deaths and 120,065 extra hospital days. The total costs attributable to excess hospital stays for MRSA and G3CREC BSIs were 44.0 and 18.1 million Euros (63.1 and 29.7 million international dollars, respectively. Based on prevailing trends, the number of BSIs caused by G3CREC is likely to rapidly increase, outnumbering the number of MRSA BSIs in the near future. CONCLUSIONS: Excess mortality associated with BSIs caused by MRSA and G3CREC is significant, and the prolongation of hospital stay imposes a considerable burden on health care systems. A foreseeable shift in

  18. Spread of Escherichia coli Strains with High-Level Cefotaxime and Ceftazidime Resistance between the Community, Long-Term Care Facilities, and Hospital Institutions

    OpenAIRE

    Oteo, Jesús; Navarro, Carmen; Cercenado, Emilia; Delgado-Iribarren, Alberto; Wilhelmi, Isabel; Orden, Beatriz; García, Carmen; Miguelañez, Silvia; Pérez-Vázquez, María; García-Cobos, Silvia; Aracil, Belén; Bautista, Verónica; Campos, José

    2006-01-01

    A total of 151 Escherichia coli strains resistant to cefotaxime and ceftazidime were isolated during a prospective surveillance study. These strains were characterized by clinical, microbiological, and molecular analyses and were distributed into four clusters of 103, 11, 6, and 5 isolates, along with 25 unrelated strains. The principal cluster was isolated from urine, wound, blood, and other samples in three hospitals, eight nursing homes, and a community healthcare center. This cluster was ...

  19. Multidrug-resistant Escherichia coli from canine urinary tract infections tend to have commensal phylotypes, lower prevalence of virulence determinants and ampC-replicons ☆

    OpenAIRE

    Wagner, Samuel; Gally, David L.; Argyle, Sally A.

    2014-01-01

    Multidrug-resistant Escherichia coli is an emerging clinical challenge in domestic species. Treatment options in many cases are limited. This study characterized MDR E. coli isolates from urinary tract infections in dogs, collected between 2002 and 2011. Isolates were evaluated in terms of β-lactamase production, phylogenetic group, ST type, replicon type and virulence marker profile. Comparisons were made with antibiotic susceptible isolates also collected from dogs with urinary tract infect...

  20. Antibiotic resistance profiles of Escherichia coli isolated from different water sources in the Mmabatho locality, Northwest Province, South Africa

    OpenAIRE

    C. Njie Ateba; D. Tonderai Kawadza; Constance N. Wose Kinge

    2010-01-01

    The antibiotic resistance profiles of Escherichia coli (E. coli), isolated from different water sources in the Mmabatho locality were evaluated. Water samples were collected from the local wastewater- and water-treatment plants, the Modimola Dam and homes in the area, and then analysed for the presence of E. coli, using standard methods. Presumptive isolates obtained were confirmed by the analytical profile index test. Antibiotic ...

  1. Silencing of NADPH-Dependent Oxidoreductase Genes (yqhD and dkgA) in Furfural-Resistant Ethanologenic Escherichia coli▿

    OpenAIRE

    Miller, E. N.; Jarboe, L. R.; Yomano, L P; York, S W; Shanmugam, K. T.; Ingram, L O

    2009-01-01

    Low concentrations of furfural are formed as a side product during the dilute acid hydrolysis of hemicellulose. Growth is inhibited by exposure to furfural but resumes after the complete reduction of furfural to the less toxic furfuryl alcohol. Growth-based selection was used to isolate a furfural-resistant mutant of ethanologenic Escherichia coli LY180, designated strain EMFR9. Based on mRNA expression levels in the parent and mutant in response to furfural challenge, genes encoding 12 oxido...

  2. No evidence for transmission of antibiotic-resistant Escherichia coli strains from humans to wild western lowland gorillas in Lope National Park, Gabon

    OpenAIRE

    Benavides, Julio Andre; Godreuil, Sylvain; Bodenham, Rebecca; Ratiarison, Sandra; Devos, Céline; Petretto, Marie-Odile; Raymond, Michel; Escobar-Páramo, Patricia

    2012-01-01

    The intensification of human activities within the habitats of wild animals is increasing the risk of interspecies disease transmission. This risk is particularly important for great apes, given their close phylogenetic relationship with humans. Areas of high human density or intense research and ecotourism activities expose apes to a high risk of disease spillover from humans. Is this risk lower in areas of low human density? We determined the prevalence of Escherichia coli antibiotic-resist...

  3. Phylogenetic groups and cephalosporin resistance genes of Escherichia coli from diseased food-producing animals in Japan

    Directory of Open Access Journals (Sweden)

    Ozawa Manao

    2011-10-01

    Full Text Available Abstract A total of 318 Escherichia coli isolates obtained from different food-producing animals affected with colibacillosis between 2001 and 2006 were subjected to phylogenetic analysis: 72 bovine isolates, 89 poultry isolates and 157 porcine isolates. Overall, the phylogenetic group A was predominant in isolates from cattle (36/72, 50% and pigs (101/157, 64.3% whereas groups A (44/89, 49.4% and D (40/89, 44.9% were predominant in isolates from poultry. In addition, group B2 was not found among diseased food-producing animals except for a poultry isolate. Thus, the phylogenetic group distribution of E. coli from diseased animals was different by animal species. Among the 318 isolates, cefazolin resistance (minimum inhibitory concentrations: ≥32 μg/ml was found in six bovine isolates, 29 poultry isolates and three porcine isolates. Of them, 11 isolates (nine from poultry and two from cattle produced extended spectrum β-lactamase (ESBL. The two bovine isolates produced blaCTX-M-2, while the nine poultry isolates produced blaCTX-M-25 (4, blaSHV-2 (3, blaCTX-M-15 (1 and blaCTX-M-2 (1. Thus, our results showed that several types of ESBL were identified and three types of β-lactamase (SHV-2, CTX-M-25 and CTX-M-15 were observed for the first time in E. coli from diseased animals in Japan.

  4. Detection and reporting beta-lactam resistance phenotypes in Escherichia coli and Klebsiella pneumoniae: a multicenter proficiency study in Spain.

    Science.gov (United States)

    Conejo, M Carmen; Mata, C; Navarro, F; Pascual, A

    2008-11-01

    The ability of 57 Spanish microbiology laboratories in detecting and reporting beta-lactam resistance phenotypes in Escherichia coli and Klebsiella pneumoniae was evaluated. Laboratories received 6 well-characterized isolates expressing the most widespread extended-spectrum beta-lactamases (ESBLs) in Spain (4 CTX-M type, 1 TEM type, and 1 SHV type), 3 isolates producing AmpC-type enzymes (2 plasmid mediated and 1 E. coli hyperproducing its chromosomal AmpC), and 3 quality control strains. Ninety-one percent of laboratories recognized all ESBL producers correctly, and therefore, low error rates were observed when testing cephalosporins and aztreonam. The highest error rates were observed with combinations of penicillin plus beta-lactamase inhibitor, although more than 60% of cases were due to the interpretation made by the microbiologists. Correct recognition of all AmpC beta-lactamase-producing strains occurred in only 47.4% of laboratories. These isolates were wrongly reported as ESBL producers and penicillinase hyperproducers in 7.6 % and 5.8% of cases, respectively. Detection of the AmpC-type phenotype by Spanish laboratories needs to be improved. PMID:18692340

  5. CTX-M-14, CTX-M-24 and resistance in Escherichia coli and Klebsiella pneumoniae clinical isolates

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Extended-spectrum β-lactamases (ESBLs) are the main cause of resistance to the third and forth-generation cephalosporins in Enterobacteriaceae, which are mediated by plasmids and can hydrolyze oxyiminoaminothiazolyl cephalosporins and mono- bactams.1 Most of ESBLs are mutants of the classical TEM and SHV types, with one or more amino-acid substitution(s) in the active site. β-lactamase inhibitors, such as clavulanic acid, can inhibit their activities. Recently, The cefotaximases (CTX-M) group, a new family of plasmid-mediated ESBLs, reported from many countries increasingly, preferentially hydrolyzes cefotaxime.2 So far, CTX-M-3 has been the most prevalent type of ESBL in China and widespread in Enterobacteriaceae, while other CTX-M type ESBLs are few reported.3 In this study, we identified the CTX-M-14 and CTX-M-24 in Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) clinical isolates from patients in Shanghai Huashan Hospital in 1999.

  6. Human Intestinal Cells Modulate Conjugational Transfer of Multidrug Resistance Plasmids between Clinical Escherichia coli Isolates

    DEFF Research Database (Denmark)

    Machado, Ana Manuel; Sommer, Morten

    2014-01-01

    Bacterial conjugation in the human gut microbiota is believed to play a major role in the dissemination of antibiotic resistance genes and virulence plasmids. However, the modulation of bacterial conjugation by the human host remains poorly understood and there is a need for controlled systems to...... the intestinal cells exposed to bacteria leading to a two-fold reduction in conjugation efficiency. These results show that human gut epithelial cells can modulate bacterial conjugation and may have relevance to gene exchange in the gut....

  7. Production of L-threonine by auxotrophs and analogue resistant mutants of Escherichia coli

    International Nuclear Information System (INIS)

    A threonine overproducer, E. coli TF427, which is resistant to threonine analogue, α-amino-β-hydroxyvaleric acid (AHV), and requires both methionine and isoleucine was developed by the mutations of E. coli W3110 using N-methyl-N'-nitro-N-nitrosoguanidine (NTG) and UV. The E. coli TF427 produced 46.5 g/l of threonine in a 5-L jar fermentor after 44 hr cultivation. The aspartokinase I of TF427 was not inhibited by threonine, and its synthesis was not repressed by threonine plus isoleucine

  8. Chromate Reductase YieF from Escherichia coli Enhances Hexavalent Chromium Resistance of Human HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Xuan Liu

    2015-05-01

    Full Text Available Hexavalent chromium (Cr(VI is a serious environmental pollutant and human toxicant. Mammalian cells are very sensitive to chromate as they lack efficient chromate detoxifying strategy, e.g., chromate-reducing genes that are widely present in prokaryotes. To test whether introduction of prokaryotic chromate-reducing gene into mammalian cells could render higher chromate resistance, an Escherichia coli chromate-reducing gene yieF was transfected into human HepG2 cells. The expression of yieF was measured in stably transfected cells HepG2-YieF by quantitative RT-PCR and found up-regulated by 3.89-fold upon Cr(VI induction. In chromate-reducing ability test, HepG2-YieF cells that harbored the reductase showed significantly higher reducing ability of Cr(VI than HepG2 control cells. This result was further supported by the evidence of increased Cr(VI-removing ability of crude cell extract of HepG2-YieF. Moreover, HepG2-YieF demonstrated 10% higher viability and decreased expression of GSH synthesizing enzymes under Cr(VI stress. Subcellular localization of YieF was determined by tracing GFP-YieF fusion protein that was detected in both nucleus and cytoplasm by laser confocal microscopy. Altogether, this study successfully demonstrated that the expression of a prokaryotic Cr(VI-reducing gene yieF endowed mammalian cell HepG2 with enhanced chromate resistance, which brought new insight of Cr(VI detoxification in mammalian cells.

  9. Class 1 integrons contributes to antibiotic resistance among clinical isolates of Escherichia coli producing extended-spectrum beta-lactamases

    Directory of Open Access Journals (Sweden)

    T Chen

    2013-01-01

    Full Text Available Objectives: The objective of this study is to determine the prevalence of antibiotic resistance factors, including the production of extended-spectrum beta-lactamases (ESBLs and the presence of class 1 integrons among Escherichia coli isolated from clinical specimens. Materials and Methods: Bacterial species identification was performed using a VITEK-2 system (VITEK2 GN-card; bioMérieux, France. Antimicrobial susceptibility testing was determined using the disk diffusion method according to the 2010 Clinical and Laboratory Standards Institute guidelines. Polymerase chain reaction (PCR was used to detect integrons and amplify variable regions of the bla TEM, bla SHV and bla CTX-M genes. Gene cassettes were detected by deoxyribonucleic acid sequencing. Results: In this study, 58% (100/172 of clinical E. coli isolates were identified as ESBL producers. We found that 90% of the ESBL-producing E. coli isolates harbored the blaCTX-M gene, whereas only 59% and 32% possessed the blaTEM and blaSHV genes respectively. The presence of class 1 integrons was based on the detection of the integrase gene by PCR. A total of 69% of the ESBL-producing isolates were integron-positive. Resistance to 10 antibiotics, including quinolones, sulfonamides and β-lactam/enzyme inhibitors, was significantly higher in the class 1 integron-positive isolates (P < 0.05. The occurrence of class 1 integrons in blaTEM , blaSHV and blaCTX-M gene carriers was 72.9%, 84.4% and 68.9%, respectively. Class 1 integrons were detected in 61.5% of the isolates with only one ESBL genotype, but in 69.0% and 92.3% of the isolates with two or three different ESBL genotypes, respectively. Conclusions: Our findings indicate that clinical strains of bacteria with multiple ESBL genotypes may have greater opportunities to carry class 1 integrons.

  10. Antibiotic resistant Esherichia coli strains from seafood and its susceptibility to seaweed extracts

    Institute of Scientific and Technical Information of China (English)

    Subramanian Kumaran; Balaraman Deivasigamani; Kumarappan Alagappan; Mannikam Sakthivel; Rajamani Karthikeyan

    2010-01-01

    Objective: To determine the prevalence and antibiotic resistance of Escherichia coli (E.coli) , in seafood obtained from Cuddalore and Parangipettai fish landing centres. Also, to identify the susceptibility of E. coli against predominant seaweeds red alga Kappaphycusalvarezii (K. alvarezii) and brown alga Padina boergessenii (P. boergessenii) extracts as sulfated polysaccharides and polyphenols respectively. Methods: A total of 48 samples (Two stations Cuddalore and Parangipettai, Tamil Nadu, India). Sampling area are fish landing centre where fishes caught from sea and estuary, seafood processing plants (packing and ice packed fishes) and local fish markets (fish samples). After isolation totally 80 strains were analyzed for its antimicrobial resistance and sensitivity against commercially 10 antibiotics. The ampicillin resistant E. coli CE21 was identified through molecular techniques as 16S rDNA sequencing. Two seaweeds K. alvarezii and P. boergessenii were screened for antibacterial activity against 12 antibiotic resistant E. coli strains. Results: Totally 48 swabbed samples from two different fish handling area were characterized for total bacterial and E. coli count. Mostly, the E. coli strains were isolated from fish local market and seafood processing plants before and after packaging process. In that maximum 56.25% strains were resistant to ampicillin and the minimum 2.5% strains were resistant to chloramphenicol. Therefore, the E. coli CE21 was identified through molecular techniques E. coli (GenBank accession number GU065251), The MIC value for polyphenol extract was slightly less than sulfated polysaccharides. E. coli strain isolated from Parangipettai was considerably increased MIC value that Cuddalore. Conclusions:The polyphenol and sulfated polysaccharides showed promising inhibitory response against all antimicrobial resistant E. coli strains and in particular the inhibitory response of ampicillin resistant E. coli.

  11. Antibiotic Resistance in Escherichia Coli Strains Isolated from Urine of Inpatients and Outpatients

    Directory of Open Access Journals (Sweden)

    Abolfazl Davoodabadi

    2012-08-01

    Full Text Available The urinary tract infections regarded as a health problem around the world and not only as an agent of nosocomial infections but also infections in the community. Community acquired UTIs cause significant illness in the first 2 years of life [1]. Urinary tract infections in both inpatient and outpatient are common and widespread use of antibiotics is often the cause of emerging one or more antibiotic-resistant microorganisms [2]. Most studies have shown higher antibiotic resistance in bacterial strains isolated from hospitalized patients than outpatients. In this study, antibiogram was performed using disk diffusion susceptibility method according to NCCLS standards of the International Committee [3]. 8 different antibiotics, including ciprofloxacin (CP: 30 μg, ceftriaxone (CRO: 30 μg, cephalotin (CF: 30 μg, cefixime (CFM: 5 μg, cotrimoxazole (SXT, nalidixic acid (NA: 30 μg, nitrofurantoin (FM: 300 μg, gentamicin (GM: 10 μg were used for antibiogram. During 1388 the total number of urine samples sent to hospital microbiology laboratories valiasr (aj of Arak was 5156, of which 446 samples (65.8% were positive for E. coli culture.

  12. Molecular characterization of vancomycin-resistant enterococci and extended-spectrum beta-lactamase-containing Escherichia coli isolates in wild birds from the Azores Archipelago

    OpenAIRE

    Silva, Nuno; Igrejas, Gilberto; Rodrigues, Pedro; Rodrigues, Tiago; Gonçalves, Alexandre; Felgar, Ana; Pacheco, Rui; Gonçalves, David; Cunha, Regina; Poeta, Patrícia

    2011-01-01

    To study the prevalence of vancomycin-resistant enterococci (VRE) and extended-spectrum beta-lactamases (ESBLs) containing Escherichia coli isolates, and the mechanisms of resistance implicated, 220 faecal samples from wild birds were collected between 2006 and 2010 in the Azores Archipelago. Samples were spread in Slanetz-Bartley agar plates supplemented with 4 mg/L of vancomycin and in Levine agar plates supplemented with 2 mg/L of cefotaxime for VRE and ESBL-containing E. coli isolation, r...

  13. Suppression of thermosensitive initiation of DNA replication in a dnaR mutant of Escherichia coli by a rifampin resistance mutation in the rpoB gene.

    OpenAIRE

    Sakakibara, Y

    1995-01-01

    The thermosensitivity of the Escherichia coli dnaR130 mutant in initiation of DNA replication was suppressed by a spontaneous rifampin resistance mutation in rpoB, the gene for the beta subunit of RNA polymerase. Among the dnaR-suppressing rpoB alleles obtained was rpoB22, which was able to suppress the thermosensitivity of the dnaA46 or dnaA167 mutant, but not that of the dnaA5 mutant, in initiation of replication. Some dnaA-suppressing rpoB alleles obtained from rifampin-resistant derivativ...

  14. Inhibitor-Sensitive AmpC β-Lactamase Variant Produced by an Escherichia coli Clinical Isolate Resistant to Oxyiminocephalosporins and Cephamycins

    OpenAIRE

    Doi, Yohei; Wachino, Jun-ichi; Ishiguro, Masaji; Kurokawa, Hiroshi; Yamane, Kunikazu; Shibata, Naohiro; Shibayama, Keigo; Yokoyama, Keiko; Kato, Haru; Yagi, Tetsuya; Arakawa, Yoshichika

    2004-01-01

    Escherichia coli HKY28, a ceftazidime-resistant strain isolated from a urine specimen in Japan, produced an inhibitor-sensitive AmpC β-lactamase variant. The deduced amino acid sequence of the enzyme contained a number of substitutions and a tripeptide deletion (Gly286-Ser287-Asp288) compared with the sequence of native AmpC of E. coli. When the deletion was reverted by a 9-base insertion at the relevant site of ampC in the clone, the typical inhibitor-resistant phenotype of AmpC was restored...

  15. Solute Transport Proteins and the Outer Membrane Protein NmpC Contribute to Heat Resistance of Escherichia coli AW1.7▿

    OpenAIRE

    Ruan, Lifang; Pleitner, Aaron; Gänzle, Michael G.; McMullen, Lynn M.

    2011-01-01

    This study aimed to elucidate determinants of heat resistance in Escherichia coli by comparing the composition of membrane lipids, as well as gene expression, in heat-resistant E. coli AW1.7 and heat-sensitive E. coli GGG10 with or without heat shock. The survival of E. coli AW1.7 at late exponential phase was 100-fold higher than that of E. coli GGG10 after incubation at 60°C for 15 min. The cytoplasmic membrane of E. coli AW1.7 contained a higher proportion of saturated and cyclopropane fat...

  16. Osteopontin: an early innate immune marker of Escherichia coli mastitis harbors genetic polymorphisms with possible links with resistance to mastitis

    Directory of Open Access Journals (Sweden)

    St-Pierre Jessika

    2009-09-01

    Full Text Available Abstract Background Mastitis is the most important disease in dairy cows and it causes significant lost of profit to producers. Identification of the genes, and their variants, involved in innate immune responses is essential for the understanding of this inflammatory disease and to identify potential genetic markers for resistance to mastitis. The progeny of dairy cows would benefit from receiving favourable alleles that support greater resistance to infection, thus reducing antibiotic use. This study aims to identify a key gene in the innate immune response to mastitis, led us to evaluate its genetic association with somatic cell score (SCS, which is an indicator of clinical mastitis, and to evaluate its impact on other traits related to milk production. Results The osteopontin transcript (SPP1 was identified in the somatic cells from cows experimentally infected with Escherichia coli. By selecting bulls with extreme estimated breeding values (EBVs for SCS, which is an indicator of mammary gland health, four DNA polymorphisms in the SPP1 genomic sequence were found. Statistical analysis revealed that the SNP SPP1c.-1301G>A has an impact on EBV for SCS (P SPP1c.-1251C>T, SPP1c.-430G>A, and SPP1c.*40A>C have an impact on SCS whereas SPP1c.-1301G>A has an effect on the EBVs for milk yield (second and third lactations, fat and protein percentages (all three lactations. Analysis revealed statistically significant differences between haplotype groups at a comparison-wise level with sire EBVS for SCS for the first (P = 0.012, second (P P Conclusion This study reports the link between DNA polymorphisms of SPP1, the number of milk immune cells and, potentially, the susceptibility to mastitis. These SNPs were identified by in silico search to be located in transcription factor recognition sites which factors are presumably involved in the Th1 immune response and in the Th2 regulation pathway. Indeed, one SNP abolished the SP1 recognition site, whereas

  17. Severe sepsis facilitates intestinal colonization by extended-spectrum-β-lactamase-producing Klebsiella pneumoniae and transfer of the SHV-18 resistance gene to Escherichia coli during antimicrobial treatment.

    Science.gov (United States)

    Guan, Jun; Liu, Shaoze; Lin, Zhaofen; Li, Wenfang; Liu, Xuefeng; Chen, Dechang

    2014-01-01

    Infections caused by multidrug-resistant pathogens are frequent and life threatening in critically ill patients. To investigate whether severe sepsis affects gut colonization by resistant pathogens and genetic exchange between opportunistic pathogens, we tested the intestinal-colonization ability of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strain carrying the SHV-18 resistance gene and the transfer ability of the resistance gene to endogenous Escherichia coli under ceftriaxone treatment in rats with burn injury only or severe sepsis induced by burns plus endotoxin exposure. Without ceftriaxone treatment, the K. pneumoniae strain colonized the intestine in both septic and burned rats for a short time, with clearance occurring earlier in burn-only rats but never in sham burn rats. In both burned and septic rats, the colonization level of the challenge strain dropped at the beginning and then later increased during ceftriaxone treatment, after which it declined gradually. This pattern coincided with the change in resistance of K. pneumoniae to ceftriaxone during and after ceftriaxone treatment. Compared with burn-only injury, severe sepsis had a more significant effect on the change in antimicrobial resistance to ceftriaxone. Only in septic rats was the resistance gene successfully transferred from the challenge strain to endogenous E. coli during ceftriaxone treatment; the gene persisted for at least 4 weeks after ceftriaxone treatment. We concluded that severe sepsis can facilitate intestinal colonization by an exogenous resistant pathogen and the transfer of the resistance gene to a potential endogenous pathogen during antimicrobial treatment. PMID:24277046

  18. Prevalence of tetracycline resistance and genotypic analysis of populations of Escherichia coli from animals, carcasses and cuts processed at a pig slaughterhouse

    DEFF Research Database (Denmark)

    Shuyu, Wu; Dalsgaard, Anders; Vieira, Antonio R;

    2009-01-01

    A Danish pig slaughterhouse was visited in this study to investigate the impact of carcass processing on prevalence of tetracycline-resistant Escherichia coli, and to identify the origins of carcass contaminations with E. coli by assessing genetic diversity of E. coli populations on carcasses. A...... total of 105 carcasses were sampled at five sequential stages: after stunning, after scalding, after splitting, after cooling and after cutting. Total and tetracycline-resistant E. coli were counted for each sample and tetracycline resistance prevalence per sample was calculated by the fraction of...... tetracycline-resistant E. coli out of total E. coli. From 15 repeatedly sampled carcasses, 422 E. coli isolates from faeces, stunned carcasses, split carcasses and chilled carcasses were examined by pulse-field gel electrophoresis (PFGE) and tested for antimicrobial susceptibility. The results showed that E...

  19. Identification and antimicrobial resistance of microflora colonizing feral pig (Sus scrofa of Brazilian Pantanal

    Directory of Open Access Journals (Sweden)

    SS Lessa

    2011-06-01

    Full Text Available Antimicrobial resistance of bacteria is a worldwide problem affecting wild life by living with resistant bacteria in the environment. This study presents a discussion of outside factors environment on microflora of feral pigs (Sus scrofa from Brazilian Pantanal. Animals had samples collected from six different body sites coming from two separated geographic areas, Nhecolandia and Rio Negro regions. With routine biochemical tests and commercial kits 516 bacteria were identified, with 240 Gram-positive, predominantly staphylococci (36 and enterococci (186 strains. Among Gram-negative (GN bacteria the predominant specimens of Enterobacteriaceae (247 mainly represented by Serratia spp. (105, Escherichia coli (50, and Enterobacter spp. (40 and specimens not identified (7. Antimicrobial susceptibility was tested against 17 drugs by agar diffusion method. Staphylococci were negative to production of enterotoxins and TSST-1, with all strains sensitive towards four drugs and highest resistance toward ampicillin (17%. Enterococci presented the highest sensitivity against vancomycin (98%, ampicillin (94% and tetracycline (90%, and highest resistance pattern toward oxacillin (99%, clindamycin (83%, and cotrimoxazole (54%. In GN the highest resistance was observed with Serratia marcescens against CFL (98%, AMC (66% and AMP (60% and all drugs was most effective against E. coli SUT, TET (100%, AMP, TOB (98%, GEN, CLO (95%, CFO, CIP (93%. The results show a new profile of oxacillin-resistant enterococci from Brazilian feral pigs and suggest a limited residue and spreading of antimicrobials in the environment, possibly because of low anthropogenic impact reflected by the drug susceptibility profile of bacteria isolated.

  20. Mecanismos moleculares de resistencia antibiótica en Escherichia coli asociadas a diarrea Molecular mechanisms of antibiotic resistance in Escherichia coli- associated diarrhea

    OpenAIRE

    Susan Mosquito; Joaquim Ruiz; José Luis Bauer; Ochoa, Theresa J.

    2011-01-01

    La resistencia antibiótica es un problema emergente a nivel mundial presente en diversas bacterias, en especial en la Escherichia coli, que tiene altos porcentajes de resistencia hacia ampicilina, trimetoprim-sulfametoxazol, tetraciclina, cloramfenicol y ácido nalidíxico, lo que supone grandes complicaciones en el tratamiento antibiótico cuando este es requerido. Este aumento de resistencia antibiótica se debe a la adquisición de diferentes mecanismos moleculares de resistencia mediante mutac...

  1. Antimicrobial resistance in faecal Escherichia coli isolates from farmed red deer and wild small mammals. Detection of a multiresistant E. coli producing extended-spectrum beta-lactamase.

    Science.gov (United States)

    Alonso, C A; González-Barrio, D; Tenorio, Carmen; Ruiz-Fons, F; Torres, C

    2016-04-01

    Eighty-nine Escherichia coli isolates recovered from faeces of red deer and small mammals, cohabiting the same area, were analyzed to determine the prevalence and mechanisms of antimicrobial resistance and molecular typing. Antimicrobial resistance was detected in 6.7% of isolates, with resistances to tetracycline and quinolones being the most common. An E. coli strain carrying blaCTX-M-1 as well as other antibiotic resistant genes included in an unusual class 1 integron (Intl1-dfrA16-blaPSE-1-aadA2-cmlA1-aadA1-qacH-IS440-sul3-orf1-mef(B)Δ-IS26) was isolated from a deer. The blaCTX-M-1 gene was transferred by conjugation and transconjugants also acquired an IncN plasmid. This strain was typed as ST224, which seems to be well adapted to both clinical and environmental settings. The phylogenetic distribution of the 89 strains varied depending on the animal host. This work reveals low antimicrobial resistance levels among faecal E. coli from wild mammals, which reflects a lower selective pressure affecting these bacteria, compared to livestock. However, it is remarkable the detection of a multi-resistant ESBL-E. coli with an integron carrying clinically relevant antibiotic-resistance genes, which can contribute to the dissemination of resistance determinants among different ecosystems. PMID:27012919

  2. Transport of the lipophilic analog minocycline differs from that of tetracycline in susceptible and resistant Escherichia coli strains.

    OpenAIRE

    McMurry, L M; Cullinane, J C; Levy, S. B.

    1982-01-01

    Plasmids which specify resistance to tetracycline offer much less resistance to its more lipophilic analog, minocycline. Resistance to minocycline varies for different plasmids. In the case of plasmid R222 (bearing the class B tetracycline resistance determinant on Tn10), minocycline resistance is comparatively high (10 microgram/ml, or 6% of the tetracycline resistance level). For plasmid pIP7 (bearing the class A determinant), minocycline resistance is only 1% of the tetracycline resistance...

  3. Celulitis in Japanese Quails (coturnix coturnix japonica for Eschorichia coli: virulence factors, sensibility and profile antimicrobial resistance /Celulite em codornas (coturnix coturnix japonica causada por Escherichia coli: fatores de virulência, sensibilidade e perfil de resistência antimicrobiana

    Directory of Open Access Journals (Sweden)

    Marilda Carlos Vidotto

    2000-12-01

    Full Text Available Ten E. coli strains isolated from celulitis lesion s of Japanese quails were to evaluated antimicrobia l resistance to twent y six drugs , to pathogenicity of strains in SPF chickens embryonated eggs and virulence factors. The antimicrobials of higher efficiency wer e ampicillin, florfenicol and the lesser efficiency were erythromycin, oxacilin, lincomicin, novobiocin, penicillin, sulfonamidas, trimethoprim+sulfomethoxazo/e and tetracyicline. The majority of E. coli strains were serum resistance, the others virulence factors, hemolisin and congo red affinity, were lesser frequent on the studied strains. Pathogenicity of E. coli strains, evaluated to DL50 in embryonated eggs, had varied of 8x10 2 the 3,2x10.Dez cepas de E. coli isoladas de lesões de celulite em codornas foram avaliadas quanto a resistência antimicrobiana frente a vinte e seis drogas, a patogenicidade das amostras em ovos embrionários de galinha SPF e quanto aos fatores de virulência: hemolisinas, resistência sérica e afinidade ao vermelho congo Os antimicrobianos de maior eficiência foram ampicilinar florfenicol e os menos eficientes foram eritromicina, oxacilina. lincomicina, novobiocina. penicsilna, sulfonamida, sulfomethoxazole+ trimetoprim e tetraciclina. A maioria das amostras de E. coli foram resistentes ao soro, os outros fatores do virulência, hemolisina e afinidade ao vermelho-congo, foram menos freqüentes nas amostras estudadas. A patogenicidade das amostras de E. coli estimada através da DL50 em ovos embrionados, variaram de 8x10* a 3.2x10a.

  4. 多重耐药与药物敏感大肠杆菌菌株在体外模拟胃肠道环境的生存力研究%Study on viability of multiple drug-resistant and sensitive Escherichia coli in vitro gastrointestinal environment

    Institute of Scientific and Technical Information of China (English)

    张玫; 刘晓阳; 李开雄; 姬华; 卢士玲; 罗娟; 周红

    2014-01-01

    目的:大肠杆菌是人和温血动物肠道重要的兼性厌氧寄居菌群,也是水源和食品粪便污染指示菌。研究多重耐药型大肠杆菌和药物敏感型大肠杆菌菌株在体外模拟胃肠道环境下的生存能力,本文数据为控制有害大肠杆菌提供理论依据。方法从奎屯市超市采集30份零售食品,分离出8份大肠杆菌阳性样品,污染率为27%。利用纸片扩散法对分离的8株大肠杆菌进行耐药实验,从8株菌中选出1株具有多重耐药的E27号菌和1株药物敏感型菌株E25号菌进行人工胃液和人工肠液耐受试验。结果所测定的8株大肠杆菌对大多数耐药纸片敏感,大肠杆菌对氨苄西林和四环素耐药率较高。8株菌中有4株耐药菌和4株敏感菌。结论所选出的两株菌, E25在人工胃肠液中的耐受力较好,菌株E27在人工胃肠液中耐受力较差,敏感菌株E25要比多重耐药菌株E27菌数减少的缓慢。%ObjectiveEscherichia coliis human and warm blooded animal intestinal important facultative anaerobic microflora group. It is indicator bacteria of water and food fecal pollution. The viability of multiple drug-resistant and drug sensitiveEscherichia coli in vitro gastrointestinal environment was studied. The results provided a theoretical basis for control of harmful Escherichia coli.MethodsThe 30 retail food were collected from supermarkets of Kuitun City, the 8 positive samples were identified. The contamination rate was 27%. Then the disk diffusion method was used to conduct the drug test for 8E.coli strains isolated from 8 positive samples respectively. A multi-drug resistantE.coli E27 and a drug sensitiveE.coli E25 were implemented in artificial gastric juice and the intestinal juice by tolerance test. ResultsThe results show that the measured eight E.coliweresensitive to most drugs. The resistant bacteria were keeping resistance for ampicillin and tetracycline. There were four drug-resistant

  5. Short communication: The role of autoinducer 2 (AI-2) on antibiotic resistance regulation in an Escherichia coli strain isolated from a dairy cow with mastitis.

    Science.gov (United States)

    Xue, Ting; Yu, Lumin; Shang, Fei; Li, Wenchang; Zhang, Ming; Ni, Jingtian; Chen, Xiaolin

    2016-06-01

    Extended spectrum β-lactamase (ESBL)-positive Escherichia coli is a major etiological organism responsible for bovine mastitis. The autoinducer 2 (AI-2) quorum sensing system is widely present in many species of gram-negative and gram-positive bacteria and has been proposed to be involved in interspecies communication. In E. coli model strains, the functional mechanisms of AI-2 have been well studied; however, in clinical antibiotic-resistant E. coli strains, whether AI-2 affects the expression of antibiotic resistance genes has not been reported. In this study, we report that exogenous AI-2 increased the antibiotic resistance of a clinical E. coli strain isolated from a dairy cow with mastitis by upregulating the expression of TEM-type enzyme in an LsrR (LuxS regulated repressor)-dependent manner. PMID:27060825

  6. An Investigation of beta-lactam antibiotics resistance in Escherichia coli isolates and molecular detection of Escherichia coli O157:H7 in cage birds from Shahrekord, Iran

    OpenAIRE

    Hossein Tahmasby; Sara Barati; Hassan Momtaz; Mohammad Rafiee Dolatabadi; Mohammad Ghasemi; Seied Vahid Ahmadi Salianeh; Samaneh Mehrabiyan

    2014-01-01

    Introduction: Cage birds can harbor human pathogens and contribute to the transmission and spread of drug resistant infectious agents to human. Since many people are interested in keeping cage birds, present study was conducted in cage birds from Shahrekord to investigate the beta-lactam antibiotics resistant E. coli and molecular detection of E. coli O157:H7 that is responsible for outbreaks of human intestinal diseases and fatal haemolytic-uraemic syndrome worldwide. Materials and metho...

  7. No evidence for transmission of antibiotic-resistant Escherichia coli strains from humans to wild western lowland gorillas in Lopé National Park, Gabon.

    Science.gov (United States)

    Benavides, Julio Andre; Godreuil, Sylvain; Bodenham, Rebecca; Ratiarison, Sandra; Devos, Céline; Petretto, Marie-Odile; Raymond, Michel; Escobar-Páramo, Patricia

    2012-06-01

    The intensification of human activities within the habitats of wild animals is increasing the risk of interspecies disease transmission. This risk is particularly important for great apes, given their close phylogenetic relationship with humans. Areas of high human density or intense research and ecotourism activities expose apes to a high risk of disease spillover from humans. Is this risk lower in areas of low human density? We determined the prevalence of Escherichia coli antibiotic-resistant isolates in a population of the critically endangered western lowland gorilla (Gorilla gorilla gorilla) and other wild mammals in Lopé National Park (LNP), Gabon, and we tested whether the observed pattern could be explained by bacterial transmission from humans and domestic animals into wildlife populations. Our results show a high prevalence of antibiotic-resistant bacterial isolates in humans and low levels in gorillas and other wildlife. The significant differences in the genetic background of the resistant bacteria isolated from humans and gorillas suggest that transmission is low or does not occur between these two species. These findings indicate that the presence of antibiotic-resistant strains in wildlife do not imply direct bacteria transmission from humans. Thus, in areas of low human density, human-wildlife E. coli transmission seems to be low. The presence of antibiotic-resistant isolates in gorillas may be better explained by other mechanisms for resistance acquisition, such as horizontal gene exchange among bacteria or naturally acquired resistance. PMID:22492436

  8. Resistance patterns of bacterial isolates to antimicrobials from 3 hospitals in the United Arab Emirates

    International Nuclear Information System (INIS)

    To compare the resistance pattern of common bacterial pathogens to commonly used drugs. Information and statistics of antimicrobial resistance for 1994 and 2005 were collected from the 3 hospital microbiology laboratories in the United Arab Emirates. The resistance patterns of Staphylococcus aureus, Escherichia coli, Klebsiella spp, and Pseudomonas aeruginosa to several front-line drugs were estimated. All laboratories used automatic machines (Vitek 2), which identifies and determines minimum inhibitory concentrations simultaneously. Increased resistance was observed for Staphylococcus aureus, (n=315, 2005) to erythromycin (approximately 6 fold, Al-Ain Hospital only), cloxacillin (Al-Ain Hospital), and gentamicin (more than 3-10 folds in all hospitals). Increased penicillin resistance was not observed. For the common Gram-negative organisms, there was a high resistance to ampicillin, gentamicin, ceftriaxone, ciprofloxacin, and imipenem, which seemed to increase for Escherichia coli, (by 4.2-200%, n=305, 2005); however, there was very little resistance to imipenem (0.4%) in Tawam Hospital. Variable resistance patterns were obtained for Pseudomonas aeruginosa (n=316, 2005) and Klebsiella spp,(n=316, 2005) against aminoglycosides, cephalosporins, ciprofloxacin, and norfloxacin. Overall, there was an obvious increase in resistance of bacteria and the prevalence rate to a number of drugs from 1-120 folds during the 11-year period. (author)

  9. Analysis of Etiology and Drug Resistance of Biliary Infections

    Institute of Scientific and Technical Information of China (English)

    王欣; 李秋; 邹声泉; 孙自庸; 朱峰

    2004-01-01

    The bile was collected from fro patients with biliary infections, with the bacterium isolated to study the sensitivity of each kind of the bacterium to several antibiotics in common use. Except G- bacterium, we also found some kinds of G+ bacterium in infection bile. G- bacterium were not sensitive to Clindamycin, G+ bacterium were sensitive to Ciprofloxacin. Escherichia coli,Xanthomonas maltophilia, Enterobacter cloacae, Pseudomonas aeruginosa were sensitive to Ampicillin. G+ bacterium were not sensitive to Azactam. Enterococcus faecalis, Enterococcus faecium,Enterobacter cloacae were not sensitive to Ceftazidime. Enterococcus faecalis, Staphylococcus coagulase negative, Staphylococcus epidermidis, Pseudomonas aeruginosa were not sensitive to Ceftriaxone Sodium. We didn't found any bacterium resistance Imipenem. The possibility of the existence of G+ bacterium as well as drug resistance should be considered n patients with biliary infections.The value of susceptibility test should be respected to avoid drug abuse of antibiotics.

  10. Association of veterinary third-generation cephalosporin use with the risk of emergence of extended-spectrum-cephalosporin resistance in Escherichia coli from dairy cattle in Japan.

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    Toyotaka Sato

    Full Text Available The use of extended-spectrum cephalosporins in food animals has been suggested to increase the risk of spread of Enterobacteriaceae carrying extended-spectrum β-lactamases to humans. However, evidence that selection of extended-spectrum cephalosporin-resistant bacteria owing to the actual veterinary use of these drugs according to criteria established in cattle has not been demonstrated. In this study, we investigated the natural occurrence of cephalosporin-resistant Escherichia coli in dairy cattle following clinical application of ceftiofur. E. coli isolates were obtained from rectal samples of treated and untreated cattle (n = 20/group cultured on deoxycholate-hydrogen sulfide-lactose agar in the presence or absence of ceftiofur. Eleven cefazoline-resistant isolates were obtained from two of the ceftiofur-treated cattle; no cefazoline-resistant isolates were found in untreated cattle. The cefazoline-resistant isolates had mutations in the chromosomal ampC promoter region and remained susceptible to ceftiofur. Eighteen extended-spectrum cephalosporin-resistant isolates from two ceftiofur-treated cows were obtained on ceftiofur-supplemented agar; no extended-spectrum cephalosporin-resistant isolates were obtained from untreated cattle. These extended-spectrum cephalosporin-resistant isolates possessed plasmid-mediated β-lactamase genes, including bla(CTX-M-2 (9 isolates, bla(CTX-M-14 (8 isolates, or bla(CMY-2 (1 isolate; isolates possessing bla(CTX-M-2 and bla(CTX-M-14 were clonally related. These genes were located on self-transmissible plasmids. Our results suggest that appropriate veterinary use of ceftiofur did not trigger growth extended-spectrum cephalosporin-resistant E. coli in the bovine rectal flora; however, ceftiofur selection in vitro suggested that additional ceftiofur exposure enhanced selection for specific extended-spectrum cephalosporin-resistant β-lactamase-expressing E. coli clones.

  11. Trends in Expanded-Spectrum Cephalosporin-Resistant Escherichia coli and Klebsiella pneumoniae among Dutch Clinical Isolates, from 2008 to 2012.

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    Matthijs van der Steen

    Full Text Available We investigated time trends in extended-spectrum cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae isolates from different patient settings in The Netherlands from 2008-2012. E. coli and K. pneumoniae isolates from blood and urine samples of patients > = 18 years were selected from the Dutch Infectious Disease Surveillance System-Antimicrobial Resistance (ISIS-AR database. We used multivariable Poisson regression to study the rate per year of blood stream infections by susceptible and resistant isolates, and generalized estimating equation (GEE log-binomial regression for trends in the proportion of extended-spectrum cephalosporin-resistant isolates. Susceptibility data of 197,513 E. coli and 38,244 K. pneumoniae isolates were included. The proportion of extended-spectrum cephalosporin-resistant E. coli and K. pneumoniae isolates from urine and blood samples increased in all patient settings, except for K. pneumoniae isolates from patients admitted to intensive care units. For K. pneumoniae, there was a different time trend between various patient groups (p<0.01, with a significantly higher increase in extended-spectrum cephalosporin-resistant isolates from patients attending a general practitioner than in isolates from hospitalized patients. For E. coli, the increasing time trends did not differ among different patient groups. This nationwide study shows a general increase in extended-spectrum cephalosporin-resistant E. coli and K. pneumoniae isolates. However, differences in trends between E. coli en K. pneumoniae underline the importance of E. coli as a community-pathogen and its subsequent influence on hospital resistance level, while for K. pneumoniae the level of resistance within the hospital seems less influenced by the resistance trends in the community.

  12. Detection of mcr-1 encoding plasmid-mediated colistin-resistant Escherichia coli isolates from human bloodstream infection and imported chicken meat, Denmark 2015.

    Science.gov (United States)

    Hasman, Henrik; Hammerum, Anette M; Hansen, Frank; Hendriksen, Rene S; Olesen, Bente; Agersø, Yvonne; Zankari, Ea; Leekitcharoenphon, Pimlapas; Stegger, Marc; Kaas, Rolf S; Cavaco, Lina M; Hansen, Dennis S; Aarestrup, Frank M; Skov, Robert L

    2015-01-01

    The plasmid-mediated colistin resistance gene, mcr-1, was detected in an Escherichia coli isolate from a Danish patient with bloodstream infection and in five E. coli isolates from imported chicken meat. One isolate from chicken meat belonged to the epidemic spreading sequence type ST131. In addition to IncI2, an incX4 replicon was found to be linked to mcr-1. This report follows a recent detection of mcr-1 in E. coli from animals, food and humans in China. PMID:26676364

  13. Virulence factors, antimicrobial resistance, and plasmid content of Escherichia coli isolated in swine commercial farms Fatores de virulência, resistência aos antimicrobianos, presença de plasmídeos em Escherichia coli isoladas de amostras clínicas e ambientais de suínos

    OpenAIRE

    M.M. Costa; G. Drescher; F Maboni; S.S. Weber; A. Schrank; Vainstein, M. H.; I.S. Schrank; A.C Vargas

    2010-01-01

    Virulence factors and antimicrobial resistance patterns of Escherichia coli isolates were evaluated. A total of 80 E. coli isolates were evaluated, being 64 from clinical samples (intestinal content and fragments of organs from diarrheic piglets), seven from feces of clinically healthy piglets and sows, and nine environmental samples (five from facilities, two from feed, one from insect, and one from waste). Molecular characterization was performed by PCR detection of fimbriae and toxin genes...

  14. Effect of the lexA gene of deinococcus radiodurans on the resistance of escherichia coli to γ-rays and MMC

    International Nuclear Information System (INIS)

    The work is to study the effect of lexA gene of Deinococcus radiodurans expressed in Escherichia coli on its resistance to γ-rays and MMC. Recombinant plasmid pZA172 was constructed by cloning the lexA gene of Deinococcus radiodurans into the vector plasmid PUC 19 in the downstream of lacZ promoter. Transfected Escherichia coli strain JM109 (pZA172) was obtained through transfection of JM109 strain with pZA172 by electroporation. Expression of the lexA protein in the IPTG-INDUCED JM109 (Pza172) was checked by SDS-PAGE, and survival curve of the strain was measured using colony formation assay after treatment with different doses of radiation and different concentrations of MMC. After IPTG induction, the lexA protein was significantly expressed in the strain JM109 (pZA172), and the survival rate of the strain was higher than that of the control. The expression of Deinococcus radiodurans lexA gene in Escherichia coli resulted in the increase of sensitivity of the latter to γ-rays and MMC. Mechanism of the effect remains to be further investigated

  15. 21 CFR 522.90 - Ampicillin implantation and injectible dosage forms.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ampicillin implantation and injectible dosage... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.90 Ampicillin implantation and injectible dosage forms....

  16. Potential pathogens, antimicrobial patterns and genotypic diversity of Escherichia coli isolates in constructed wetlands treating swine wastewater.

    Science.gov (United States)

    Ibekwe, A M; Murinda, Shelton E; DebRoy, Chitrita; Reddy, Gudigopura B

    2016-02-01

    Escherichia coli populations originating from swine houses through constructed wetlands were analyzed for potential pathogens, antimicrobial susceptibility patterns, and genotypic diversity. Escherichia coli isolates (n = 493) were screened for the presence of the following virulence genes: stx1, stx2 and eae (Shiga toxin-producing E. coli [STEC]), heat-labile enterotoxin (LT) genes and heat stable toxin STa and STb (enterotoxigenic E. coli (ETEC), cytotoxin necrotizing factors 1 and 2 (cnf1 and cnf2 [necrotoxigenic E. coli- NTEC]), as well as O and H antigens, and the presence of the antibiotic resistance genes blaTEM, blaSHV, blaCMY-2, tet A, tet B, tet C, mph(A), aadA, StrA/B, sul1, sul2 and sul3. The commensal strains were further screened for 16 antimicrobials and characterized by BOX AIR-1 PCR for unique genotypes. The highest antibiotic resistance prevalence was for tetracycline, followed by erythromycin, ampicillin, streptomycin, sulfisoxazole and kanamycin. Our data showed that most of the isolates had high distribution of single or multidrug-resistant (MDR) genotypes. Therefore, the occurrence of MDR E. coli in the wetland is a matter of great concern due to possible transfer of resistance genes from nonpathogenic to pathogenic strains or vice versa in the environment. PMID:26839381

  17. Antibacterial Effects of Gold Nanoparticles on Multi-sdrug Resistant Klebsiella Pneumoniae and Escherichia Coli and Its Effect on the Liver of Balb/C mice

    Directory of Open Access Journals (Sweden)

    L Rahimzade Torabi

    2016-01-01

    Full Text Available Introduction: The gold nanoparticles as other nanoparticles have catalytic, magnetic, optical, and biological (antimicrobial properties. On the other hand, resistance to antibiotics is one of the greatest public health problems posed in the world. Therefore, the present study aimed to investigate the antibacterial effects of gold nanoparticles on multi-drug resistant klebsiella pneumoniae as well as escherichia coli and its effect on the liver of balb/c mice. Methods: In this study, multi-drug resistant Klebsiella pneumoniae and Escherichia coli bacteria clinical samples were utilized that were isolated from several hospitals in Isfahan and then the toxic effects of nanoparticles were investigated on the Balb / C mice. Colloidal gold nanoparticles were also applied with spherical shape and a concentration of 200 ppm in size of 10 nm, using two wells and disk agar diffusion method. Antibacterial properties of the nanoparticles were evaluated within 1-3 days with 37 ˚c temperature, and diameter of inhibitory zone of growth was measured every day. Tissue and liver enzymes of the mice were examined, as well. Results: The greatest diameter of inhibitory zone was detected in multi drug resistant E. coli. Most of the MIC and MBC were found in multi-drug resistant Klebsiella pneumoniae bacteria .Gold nanoparticles did not reveal any significant changes on the weight, liver enzymes and liver tissue of Balb / C mice after one month. Conclusion: As the findings of the current study revealed, inhibitory effect of gold nanoparticles was observed on the axamined microorganism. Although the laboratories findings are promising, more studies should be conducted in regard with therapeutic standardization.

  18. An Investigation of beta-lactam antibiotics resistance in Escherichia coli isolates and molecular detection of Escherichia coli O157:H7 in cage birds from Shahrekord, Iran

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    Hossein Tahmasby

    2014-04-01

    Full Text Available Introduction: Cage birds can harbor human pathogens and contribute to the transmission and spread of drug resistant infectious agents to human. Since many people are interested in keeping cage birds, present study was conducted in cage birds from Shahrekord to investigate the beta-lactam antibiotics resistant E. coli and molecular detection of E. coli O157:H7 that is responsible for outbreaks of human intestinal diseases and fatal haemolytic-uraemic syndrome worldwide. Materials and methods: Altogether 256 samples of cage birds (lovebirds, quails, nightingales, parrots, mynahs, goldfinchs, finches, kingbirds, peacocks, and pheasants faeces were collected with sterile cotton swabs from different areas of Shahrekord, Iran. Swabs were placed directly into Tryptone Soya Broth (TSB. In the laboratory, samples were streaked onto MacConkey agar and also Sorbitol MacConkey agar as selective plating media. Then, antibiogram tests were performed using disc diffusion method. Suspected colonies to E. coli O157:H7 were tested by polymerase chain reaction (PCR. Results: E. coli was isolated from 31 (12.1% out of 256 the samples. Resistance of isolates to Imipenem, Cefotaxime, Cefixime, Cefalexin, Amoxicillin, Penicillin G and Oxacillin was 0, 3.2, 16.1, 90.3, 100, 100 and 100% respectively. E. coli O157:H7 was not found in any samples. Discussion and conclusion: Although cage birds were not sourcee or carriers of E. coli O157:H7 in the studied region, they harbored beta-lactam antibiotics resistant E. coli and could be an important component of drug-resistant infections transmission from cage-birds to human, especially to kids and can pose a potential risk to human health. For this reason, it is recommended to make pet birds owners and general public aware of potential dangers of cage bird keeping.

  19. Quinolone co-resistance in ESBL- or AmpC-producing Escherichia coli from an Indian urban aquatic environment and their public health implications.

    Science.gov (United States)

    Bajaj, Priyanka; Kanaujia, Pawan Kumar; Singh, Nambram Somendro; Sharma, Shalu; Kumar, Shakti; Virdi, Jugsharan Singh

    2016-01-01

    Quinolone and β-lactam antibiotics constitute major mainstay of treatment against infections caused by pathogenic Escherichia coli. Presence of E. coli strains expressing co-resistance to both these antibiotic classes in urban aquatic environments which are consistently being used for various anthropogenic activities represents a serious public health concern. From a heterogeneous collection of 61 E. coli strains isolated from the river Yamuna traversing through the National Capital Territory of Delhi (India), those harboring blaCTX-M-15 (n = 10) or blaCMY-42 (n = 2) were investigated for co-resistance to quinolones and the molecular mechanisms thereof. Resistance was primarily attributed to amino acid substitutions in the quinolone resistance-determining regions (QRDRs) of GyrA (S83L ± D87N) and ParC (S80I ± E84K). One of the E. coli strains, viz., IPE, also carried substitutions in GyrB and ParE at positions Ser492→Asn and Ser458→Ala, respectively. The phenotypically susceptible strains nevertheless carried plasmid-mediated quinolone resistance (PMQR) gene, viz., qnrS, which showed co-transfer to the recipient quinolone-sensitive E. coli J53 along with the genes encoding β-lactamases and led to increase in minimal inhibitory concentrations of quinolone antibiotics. To the best of our knowledge, this represents first report of molecular characterization of quinolone co-resistance in E. coli harboring genes for ESBLs or AmpC β-lactamases from a natural aquatic environment of India. The study warrants true appreciation of the potential of urban aquatic environments in the emergence and spread of multi-drug resistance and underscores the need to characterize resistance genetic elements vis-à-vis their public health implications, irrespective of apparent phenotypic resistance. PMID:26498967

  20. Resistance of uropathogenic strains of Escherichia coli in pregnant women and other women in generative ages in comparison with antibiotics consumption in Zagreb

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    Marcel Leppée,

    2010-02-01

    Full Text Available Aim To compare resistance of uropathogenic strains of Escherichia coli (UPEC to antibiotics in women in generative ages and pregnant women during two year period (2004 and 2008 in Zagreb, andcomparison of resistance and the consumption of antibiotics. Methods The standard disk-diffusion method was used for sensitivity testing to 16 different antibiotics.Data on antibiotic utilization were used to calculate the number of defined daily doses (DDD and DDD per 1000 inhabitants using Anatomical-Therapeutic-Chemical/DDD methodology.Data on antibiotic consumption during pregnancy were collected using a questionnaire filled in by 893 women after delivery.Results During 2004 resistance of UPEC to antimicrobial drugs was not different in pregnant and in non-pregnant women, with the exception of amoxicillin and nitrofurantoin, with statistically higher resistance in pregnant women (p <0.01. Four years later the statistically higher resistance to norfloxacin was observed in non-pregnant women (p <0.01. Comparing the resistance in 2004 and 2008, in the both groups of women a statistically significant decrease of resistance to cefalexin and nitrofurantoin was detected (p <0.01. Outpatient utilization of antimicrobial drugs in Zagreb increased significantly, from 32 to 39 DDD/1000 inhabitants per day. The most used antibiotic was co-amoxiclav, and its utilization increased from 9.6 to 12.2 DDD/1000/day. Amoxicillin and co-amoxiclav were used during pregnancy by 9.6% interviewed women. Conclusion The observed significant decrease of resistance to cefalexin makes that antibiotic the drug of choice for treatment of urinary tract infections in women in generative ages, and together with coamoxiclavcan be administered in pregnancy. Constant monitoring of urinary tract pathogens resistance to antimicrobial agents ensures the effectiveness of empirical therapy, whose versatile use is limited due the potentially harmful effects of antimicrobial drugs on fetus.