Novel Method for Rapid Assessment of Antibiotic Resistance in Escherichia coli Isolates from Environmental Waters by Use of a Modified Chromogenic Agar

ABSTRACT We validated a novel method for screening Escherichia coli resistance to antibiotics in environmental samples using modified Difco MI agar (Becton Dickinson) impregnated with selected antibiotics (tetracycline, ampicillin, cephalexin, and sulfamethoxazole), termed MI-R. This method combines an existing rapid assessment technique for E. coli enumeration with clinical reference data for breakpoint analysis of antibiotic resistance and was developed to address issues encountered when clinical methods are used with environmental samples. Initial trials conducted using strains of E. coli with resistance to the selected antibiotics showed that this method was reproducible and accurate with respect to antibiotic resistance. Trials using wastewater effluent demonstrated the precision of the method, and the levels of resistance found in effluent were directly comparable to the levels of antibiotic resistance determined using the more traditional CLSI (formerly NCCLS) disk susceptibility test. All wastewater isolates growing on MI-R plates were confirmed to be resistant using the CLSI disk susceptibility test. Bacterial resistance to ampicillin (38% ± 4% overall), sulfamethoxazole, tetracycline (21% ± 3% overall), and ciprofloxacin (6% ± 1%) were found in wastewater effluent. A successful trial was also conducted with water collected from the Brisbane River, Australia. The levels of antibiotic resistance in E. coli ranged from 0 to 47% for ampicillin, from 0 to 24% for tetracycline, from 0 to 63% for sulfamethoxazole, and from 0 to 1% for ciprofloxacin, with the highest incidence of resistance associated with wastewater treatment plant discharges. This method has great potential for rapid and representative assessment of antibiotic resistance in E. coli and could allow increased sample analysis, resulting in greater confidence in spatial analysis in environmental studies.

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Antimicrobial susceptibility and diarrheagenic diagnosis of Escherichia coli and Salmonella enterica isolated from feral pigeons (Columba livia) captured in Fortaleza, Brazil

Pesquisa Veterinária Brasileira ◽

10.1590/1678-5150-pvb-5633 ◽

2018 ◽

Vol 38 (11) ◽

pp. 2150-2154 ◽

Cited By ~ 2

Author(s):

Ruben V. Horn ◽

Windleyanne G.A. Bezerra ◽

Elisângela S. Lopes ◽

Régis S.C. Teixeira ◽

Isaac N.G. Silva ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Salmonella Enterica ◽

Columba Livia ◽

Susceptibility Test ◽

Antimicrobial Susceptibility Test ◽

E Coli ◽

Feral Pigeons

ABSTRACT: This study aimed to isolate Escherichia coli and Salmonella enterica from captured feral pigeons in Fortaleza, Brazil, and, in addition to evaluate the antimicrobial susceptibility profiles and diagnose diarrheagenic E. coli strains. Pigeons were captured in four public locations in Fortaleza with three techniques. Individual cloacal swab samples were collected and submitted to bacterial isolation, biochemical identification and antimicrobial susceptibility test. Disk diffusion technique was used with twelve antibiotics. E. coli strains were submitted to DNA extraction followed by PCR to diagnose five diarrheagenic pathotypes. A total of 124 birds were captured. One bird was positive for Salmonella enterica (0.81%) and 121 (97.58%) were positive for E. coli. Among these, 110 isolates were submitted to antimicrobial susceptibility test and 28.18% (31/110) presented resistance to at least one antibiotic. Resistance to azithromycin was the most frequent (21.82%), followed by tetracycline (10.91%) and sulfamethoxazole with trimethoprim (8.9%). Multidrug resistance, calculated as a resistance to at least 3 antimicrobial classes, was identified in 3.64% (4/110) of strains. The maximum number of antimicrobial classes to which one strain was resistant was seven. Results demonstrated nine different resistance profiles and the most frequent was tetracycline and sulfamethoxazole with trimethoprim (4 strains), followed by chloramphenicol, azithromycin, tetracycline and sulfamethoxazole with trimethoprim (3 strains). Amoxicillin with clavulanic acid and tobramycin presented lowest levels of antimicrobial resistance, to which none of the tested strains were resistant. A single strain was positive for the eltB gene, which is a diagnostic tool to identify the Enterotoxigenic E. coli (ETEC) pathotype. None of the other investigated genes (stx1, stx2, estA, eaeA, ipaH, aatA and aaiC) were identified. The single isolate of S. enterica was a rough strain of Salmonella enterica subsp. enterica, but serotype identification was not possible. However, this isolate presented resistance to amoxicillin, amoxicillin with clavulanic acid, tetracycline and sulfamethoxazole with trimethoprim. Therefore, captured feral pigeons of Fortaleza presented a low prevalence of S. enterica and diarrheagenic E. coli. Considering the investigated pathogens, our results suggest a good health status and a low public health risk. However, important antimicrobial resistance profiles were identified.

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Vibrio cholerae Triggers SOS and Mutagenesis in Response to a Wide Range of Antibiotics: a Route towards Multiresistance

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01549-10 ◽

2011 ◽

Vol 55 (5) ◽

pp. 2438-2441 ◽

Cited By ~ 107

Author(s):

Zeynep Baharoglu ◽

Didier Mazel

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Vibrio Cholerae ◽

Fluorescent Protein ◽

Resistance Development ◽

Content Type ◽

E Coli ◽

Wide Range ◽

Green Fluorescent ◽

Regulated Promoters

ABSTRACTAntibiotic resistance development has been linked to the bacterial SOS stress response. InEscherichia coli, fluoroquinolones are known to induce SOS, whereas other antibiotics, such as aminoglycosides, tetracycline, and chloramphenicol, do not. Here we address whether various antibiotics induce SOS inVibrio cholerae. Reporter green fluorescent protein (GFP) fusions were used to measure the response of SOS-regulated promoters to subinhibitory concentrations of antibiotics. We show that unlike the situation withE. coli, all these antibiotics induce SOS inV. cholerae.

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Removal improvement of bacteria (Escherichia coli and enterococci) in maturation ponds using baffles

Water Science & Technology ◽

10.2166/wst.2012.896 ◽

2012 ◽

Vol 65 (4) ◽

pp. 589-595 ◽

Cited By ~ 5

Author(s):

A. Ouali ◽

H. Jupsin ◽

J. L. Vasel ◽

L. Marouani ◽

A. Ghrabi

Keyword(s):

Escherichia Coli ◽

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

E Coli ◽

Conventional Activated Sludge ◽

In Series ◽

Hydrodynamic Study ◽

Rhodamine Wt ◽

Engineering Intervention

Korba wastewater treatment plant is a conventional activated sludge followed by three maturation ponds (MP1, MP2, MP3) in series acting as a tertiary treatment. The first study of wastewater treatment plants showed that the effluent concentration of Escherichia coli and enterococci at the outlet of the (MP3) varies between 103 and 104CFU/100 ml. After the hydrodynamic study conducted by Rhodamine WT which showed short-circuiting in the MP1, two baffles were introduced in the first maturation pond (MP1) to improve the hydrodynamic and the sanitary performances. The second hydraulic study showed that the dispersion number ‘d’ was reduced from 1.45 to 0.43 by this engineering intervention and the Peclet number was raised from 0.69 to 2.32. The hydraulic retention time was increased by 14 h. Because of well-designed baffles, the removal efficiency of E. coli and enterococci was raised between 0.2 and 0.7 log units for the first maturation pond.

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Assessing the population dynamics of Escherichia coli in a metropolitan river after an extreme flood event

Journal of Water and Health ◽

10.2166/wh.2016.285 ◽

2016 ◽

Vol 15 (2) ◽

pp. 196-208 ◽

Cited By ~ 1

Author(s):

Nicole M. Masters ◽

Aaron Wiegand ◽

Jasmin M. Thompson ◽

Tara L. Vollmerhausen ◽

Eva Hatje ◽

...

Keyword(s):

Escherichia Coli ◽

Population Dynamics ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Wastewater Treatment Plants ◽

Vero Cells ◽

Flood Event ◽

Typing Method ◽

E Coli ◽

Extreme Flood

We investigated Escherichia coli populations in a metropolitan river after an extreme flood event. Between nine and 15 of the 23 selected sites along the river were sampled fortnightly over three rounds. In all, 307 E. coli were typed using the PhP typing method and were grouped into common (C) or single (S) biochemical phenotypes (BPTs). A representative from each of the 31 identified C-BPTs was tested for 58 virulence genes (VGs) associated with intestinal and extra-intestinal E. coli, resistance to 22 antibiotics, production of biofilm and cytotoxicity to Vero cells. The number of E. coli in the first sampling round was significantly (P < 0.01) higher than subsequent rounds, whereas the number of VGs was significantly (P < 0.05) higher in isolates from the last sampling round when compared to previous rounds. Comparison of the C-BPTs with an existing database from wastewater treatment plants (WWTPs) in the same catchment showed that 40.6% of the river isolates were identical to the WWTP isolates. The relatively high number of VGs and antibiotic resistance among the C-BPTs suggests possessing and retaining these genes may provide niche advantages for those naturalised and/or persistent E. coli populations which may pose a health risk to the community.

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Mechanisms of Resistance in Multiple-Antibiotic-Resistant Escherichia coli Strains of Human, Animal, and Food Origins

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.48.10.3996-4001.2004 ◽

2004 ◽

Vol 48 (10) ◽

pp. 3996-4001 ◽

Cited By ~ 269

Author(s):

Yolanda Sáenz ◽

Laura Briñas ◽

Elena Domínguez ◽

Joaquim Ruiz ◽

Myriam Zarazaga ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Amino Acid ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Mechanisms Of Resistance ◽

Antibiotic Resistant ◽

E Coli ◽

Class 1 ◽

Human Animal

ABSTRACT Seventeen multiple-antibiotic-resistant nonpathogenic Escherichia coli strains of human, animal, and food origins showed a wide variety of antibiotic resistance genes, many of them carried by class 1 and class 2 integrons. Amino acid changes in MarR and mutations in marO were identified for 15 and 14 E. coli strains, respectively.

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Impact of Feed Supplementation with Antimicrobial Agents on Growth Performance of Broiler Chickens, Clostridium perfringens and Enterococcus Counts, and Antibiotic Resistance Phenotypes and Distribution of Antimicrobial Resistance Determinants in Escherichia coli Isolates

Applied and Environmental Microbiology ◽

10.1128/aem.01086-07 ◽

2007 ◽

Vol 73 (20) ◽

pp. 6566-6576 ◽

Cited By ~ 103

Author(s):

Moussa S. Diarra ◽

Fred G. Silversides ◽

Fatoumata Diarrassouba ◽

Jane Pritchard ◽

Luke Masson ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Broiler Chickens ◽

Antimicrobial Agents ◽

Growth Promoters ◽

Feed Supplementation ◽

E Coli ◽

Resistance Determinants ◽

Class 1

ABSTRACT The effects of feed supplementation with the approved antimicrobial agents bambermycin, penicillin, salinomycin, and bacitracin or a combination of salinomycin plus bacitracin were evaluated for the incidence and distribution of antibiotic resistance in 197 commensal Escherichia coli isolates from broiler chickens over 35 days. All isolates showed some degree of multiple antibiotic resistance. Resistance to tetracycline (68.5%), amoxicillin (61.4%), ceftiofur (51.3%), spectinomycin (47.2%), and sulfonamides (42%) was most frequent. The levels of resistance to streptomycin, chloramphenicol, and gentamicin were 33.5, 35.5, and 25.3%, respectively. The overall resistance levels decreased from day 7 to day 35 (P < 0.001). Comparing treatments, the levels of resistance to ceftiofur, spectinomycin, and gentamicin (except for resistance to bacitracin treatment) were significantly higher in isolates from chickens receiving feed supplemented with salinomycin than from the other feeds (P < 0.001). Using a DNA microarray analysis capable of detecting commonly found antimicrobial resistance genes, we characterized 104 tetracycline-resistant E. coli isolates from 7- to 28-day-old chickens fed different growth promoters. Results showed a decrease in the incidence of isolates harboring tet(B), bla TEM, sulI, and aadA and class 1 integron from days 7 to 35 (P < 0.01). Of the 84 tetracycline-ceftiofur-resistant E. coli isolates, 76 (90.5%) were positive for bla CMY-2. The proportions of isolates positive for sulI, aadA, and integron class 1 were significantly higher in salinomycin-treated chickens than in the control or other treatment groups (P < 0.05). These data demonstrate that multiantibiotic-resistant E. coli isolates can be found in broiler chickens regardless of the antimicrobial growth promoters used. However, the phenotype and the distribution of resistance determinants in E. coli can be modulated by feed supplementation with some of the antimicrobial agents used in broiler chicken production.

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Spread of Antibiotic Resistance in Aquatic Environments: E. coli as a Case Study

Proceedings ◽

10.3390/proceedings2110693 ◽

2018 ◽

Vol 2 (11) ◽

pp. 693 ◽

Cited By ~ 1

Author(s):

Maria Adamantia Efstratiou ◽

Marina Bountouni ◽

Efthimios Kefalas

Keyword(s):

Escherichia Coli ◽

Drinking Water ◽

Antibiotic Resistance ◽

Rural Communities ◽

Ground Water ◽

Aquatic Environments ◽

Multiple Resistance ◽

E Coli ◽

Of Greece

The aim of this study was to gather information on the spread of antibiotic resistance in Escherichia coli isolates from wells, boreholes and untreated drinking water in islands of Greece. We analyzed for antibiotic resistance 235 E. coli strains isolated from untreated drinking water of small rural communities, and ground water from 4 islands. Resistance was tested against Norfloxacin, Ciprofloxacin, Levofloxacin, Amoxicillin and Cefaclor. More than half (54.9%) were resistant to at least one of the antibiotics tested. Of these 26.3% showed multiple resistance (to two or more antibiotics). Strains from drinking water sources were overall more sensitive. Frequent resistance was observed for Amoxicillin (38.3%) and Levofloxacin (28.5%), low for Norfloxacin (5.5%).

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Antibiotic-resistant Escherichia coli and Salmonella spp. associated with dairy cattle and farm environment having public health significance

Veterinary World ◽

10.14202/vetworld.2019.984-993 ◽

2019 ◽

Vol 12 (7) ◽

pp. 984-993 ◽

Cited By ~ 14

Author(s):

Md. Abdus Sobur ◽

Abdullah Al Momen Sabuj ◽

Ripon Sarker ◽

A. M. M. Taufiqur Rahman ◽

S. M. Lutful Kabir ◽

...

Keyword(s):

Public Health ◽

Escherichia Coli ◽

Antibiotic Resistance ◽

Resistance Genes ◽

One Health ◽

Dairy Farm ◽

Antibiotic Resistance Genes ◽

Salmonella Spp ◽

Antibiotic Resistant ◽

E Coli

Aim: The present study was carried out to determine load of total bacteria, Escherichia coli and Salmonella spp. in dairy farm and its environmental components. In addition, the antibiogram profile of the isolated bacteria having public health impact was also determined along with identification of virulence and resistance genes by polymerase chain reaction (PCR) under a one-health approach. Materials and Methods: A total of 240 samples of six types (cow dung - 15, milk - 10, milkers' hand wash - 10, soil - 10 water - 5, and vegetables - 10) were collected from four dairy farms. For enumeration, the samples were cultured onto plate count agar, eosin methylene blue, and xylose-lysine deoxycholate agar and the isolation and identification of the E. coli and Salmonella spp. were performed based on morphology, cultural, staining, and biochemical properties followed by PCR. The pathogenic strains of E. coli stx1, stx2, and rfbO157 were also identified through PCR. The isolates were subjected to antimicrobial susceptibility test against 12 commonly used antibiotics by disk diffusion method. Detection of antibiotic resistance genes ereA, tetA, tetB, and SHV were performed by PCR. Results: The mean total bacterial count, E. coli and Salmonella spp. count in the samples ranged from 4.54±0.05 to 8.65±0.06, 3.62±0.07 to 7.04±0.48, and 2.52±0.08 to 5.87±0.05 log colony-forming unit/g or ml, respectively. Out of 240 samples, 180 (75%) isolates of E. coli and 136 (56.67%) isolates of Salmonella spp. were recovered through cultural and molecular tests. Among the 180 E. coli isolates, 47 (26.11%) were found positive for the presence of all the three virulent genes, of which stx1 was the most prevalent (13.33%). Only three isolates were identified as enterohemorrhagic E. coli. Antibiotic sensitivity test revealed that both E. coli and Salmonella spp. were found highly resistant to azithromycin, tetracycline, erythromycin, oxytetracycline, and ertapenem and susceptible to gentamycin, ciprofloxacin, and imipenem. Among the four antibiotic resistance genes, the most observable was tetA (80.51-84.74%) in E. coli and Salmonella spp. and SHV genes were the lowest one (22.06-25%). Conclusion: Dairy farm and their environmental components carry antibiotic-resistant pathogenic E. coli and Salmonella spp. that are potential threat for human health which requires a one-health approach to combat the threat.

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EVALUATION OF THE IMPACT OF PLASMID CURING ON ANTIBIOTIC RESISTANCE ON SOME CLINICAL ISOLATES OF ESCHERICHIA COLI

FUDMA Journal of Sciences ◽

10.33003/fjs-2020-0403-335 ◽

2020 ◽

Vol 4 (3) ◽

pp. 323-327

Author(s):

Mamunu Abdulkadir SULAIMAN ◽

H.S Muhammad ◽

Aliyu Muhammad Sani ◽

Aminu Ibrahim ◽

Ibrahim Muhammad Hussain ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Clinical Isolates ◽

Diffusion Method ◽

Plasmid Curing ◽

Sensitivity Testing ◽

E Coli ◽

Risk Of Death ◽

Mar Index ◽

The Impact

Multidrug resistance (MDR) exhibited by some strains of Escherichia coli may be due to acquiring mobile genetic element (R-plasmid) by the bacteria, or intrinsically induced by inappropriate use of antibiotics by the hosts. Infection by such strains may result to prolonged illness and greater risk of death. The study evaluated the impact of curing on antibiotic resistance on selected clinical isolates of E. coli. Twenty clinical isolates of E. coli from our previous studies were re-characterized using conventional microbiological techniques. Antibiotic sensitivity testing was determined by disk diffusion method, MDR selected based on resistance to ≥ 2 classes of antibiotics. Multiple antibiotic resistance (MAR) index was determined as ratio of the number of antibiotic resisted to the total number of antibiotics tested and considered significant if ≥. 0.2. The isolates that showed significant MAR index were subjected to plasmid curing using acridine orange, thereafter, profiled for plasmid and the cured ones were re-tested against the antibiotics they initially resisted. Out of the 20 isolates, 19 (95%) were confirmed as E. coli, all (100%) of which were MDRs, which was highest against augmentin (78.9%) followed by amoxacillin (52.6%). However, after the plasmid curing only 6 (31.6%) out of the 19 isolates cured retained significant MAR index and the level of the significance had reduced drastically in 16 (84.2%) isolates. Conclusively, curing assay can completely eliminate R-plasmid acquired resistance. More studied on plasmid curing agents for possible augmentation of the agents into antibiotics may see the rise of successful antibiotic era again.

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The population genomics of increased virulence and antibiotic resistance in human commensal Escherichia coli over 30 years in France

10.1101/2021.06.24.449745 ◽

2021 ◽

Author(s):

Julie Marin ◽

Olivier Clermont ◽

Guilhem Royer ◽

Melanie Mercier-Darty ◽

Jean-Winoc Decousser ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

High Risk ◽

Virulence Genes ◽

Population Genomics ◽

E Coli ◽

O Antigen ◽

Similar Region ◽

Intestinal Infections ◽

Evolution Of Virulence

Escherichia coli is a commensal species of the lower intestine, but also a major pathogen causing intestinal and extra-intestinal infections. Most studies on genomic evolution of E. coli used isolates from infections, and/or focused on antibiotic resistance, but neglected the evolution of virulence. Here instead, we whole-genome sequenced a collection of 436 E. coli isolated from fecal samples of healthy adult volunteers in France between 1980 and 2010. These isolates were distributed among 159 sequence types (STs), the five most frequent being ST10 (15.6%), ST73 (5.5%) and ST95 (4.8%), ST69 (3.7%) and ST59 (3.7%), and 230 O:H serotypes. ST and serotype diversity increased over time. Comparison with 912 E. coli bacteremia isolates from similar region and time showed a greater diversity in commensal isolates. The O1, O2, O6 and O25-groups used in bioconjugate O-antigen vaccine were found in only 63% of the four main STs associated with a high risk of bacteremia (ST69, ST73, ST95 and ST131). In commensals, STs associated with a high risk of bacteremia increased in frequency. Both extra-intestinal virulence-associated genes and resistance to antibiotics increased in frequency. Evolution of virulence genes was driven by both clonal expansion of STs with more virulence genes, and increases in frequency within STs, whereas the evolution of resistance was dominated by increases in frequency within STs. This study provides a unique picture of the phylogenomic evolution of E. coli in its human commensal habitat over a 30-year period and suggests that the efficacy of O-antigen vaccines would be threatened by serotype replacement.

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