Genomic Insights into a Colistin-Resistant Uropathogenic Escherichia coli Strain of O23:H4-ST641 Lineage Harboring mcr-1.1 on a Conjugative IncHI2 Plasmid from Egypt

The reintroduction of colistin, a last-resort antibiotic for multidrug-resistant pathogens, resulted in the global spread of plasmid-mediated mobile colistin resistance (mcr) genes. Our study investigated the occurrence of colistin resistance among Escherichia coli isolated from patients with urinary tract infections admitted to a teaching hospital in Egypt. Out of 67 isolates, three isolates were colistin-resistant, having a minimum inhibitory concentration of 4 µg/mL and possessing the mcr-1 gene. A double mechanism of colistin resistance was detected; production of mcr-1 along with amino acid substitution in PmrB (E123D and Y358N) and PmrA (G144S). Broth mating experiments inferred that mcr-1 was positioned on conjugative plasmids. Whole-genome sequencing of EC13049 indicated that the isolate belonged to O23:H4-ST641 lineage and to phylogroup D. The mcr-1-bearing plasmid corresponded to IncHI2 type with a notable similarity to other E. coli plasmids previously recovered from Egypt. The unbanned use of colistin in the Egyptian agriculture sector might have created a potential reservoir for the mcr-1 gene in food-producing animals that spread to humans. More proactive regulations must be implemented to prevent further dissemination of this resistance. This is the first characterization of mcr-1-carrying IncHI2:ST4 plasmid recovered from E. coli of a clinical source in Egypt.

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Characterization of auto-agglutinating and non-typeable uropathogenic Escherichia coli strains

The Journal of Infection in Developing Countries ◽

10.3855/jidc.11098 ◽

2019 ◽

Vol 13 (06) ◽

pp. 465-472

Author(s):

Ulises Hernández-Chiñas ◽

Alejandro Pérez-Ramos ◽

Laura Belmont-Monroy ◽

María E Chávez-Berrocal ◽

Edgar González-Villalobos ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Multidrug Resistant ◽

Uropathogenic Escherichia Coli ◽

E Coli ◽

Resistant Strains ◽

Tract Infections ◽

Disk Method

Introduction: Uropathogenic Escherichia coli (UPEC) are the main etiological agent of urinary tract infections (UTIs). Association between different serotypes and UTIs is known, however, some strains are incapable to be serotyped. The aim of this work was to study bthe phenotypical and genotypical characteristics of 113 non-typeable (NT) and auto-agglutinating (AA) E. coli strains, isolated from UTIs in children and adults. Methodology: The 113 UPEC strains were analyzed by PCR assays using specific primers to determine their serogroups, fimH, papC, iutA, sat, hlyCA and cnf1, virulence associated genes, and chuA, yjaA and TSPE4.C2 for phylogroup determination. Additionally, the diffusion disk method was performed to evaluate the antimicrobial resistance to 18 antimicrobial agents. Results: Using the PCR assay, 63% (71) of the strains were genotyped showing O25 and O75 as the most common serogroups. The virulence genes fimH (86%) and iutA (74%) were the most prevalent, in relation to the phylogroups the commensal (A and B1) and virulent (B2 and D) showed similar frequencies (P > 0.05). The antimicrobial susceptibility test showed a high percentage (73%) of multidrug-resistant strains. Conclusions: The genotyping allowed identifying the serogroup in many of the strains that could not be typed by traditional serology. The strains carried virulence genes and were multidrug-resistant in both, commensal and virulent phylogroups. Our findings revealed that, in addition to the classical UPEC serogroups, there are pathogenic serogroups not reported yet.

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Three-Year Trend in Escherichia coli Antimicrobial Resistance among Children’s Urine Cultures in an Italian Metropolitan Area

Children ◽

10.3390/children8070597 ◽

2021 ◽

Vol 8 (7) ◽

pp. 597

Author(s):

Luca Pierantoni ◽

Laura Andreozzi ◽

Simone Ambretti ◽

Arianna Dondi ◽

Carlotta Biagi ◽

...

Keyword(s):

Escherichia Coli ◽

Metropolitan Area ◽

Bacterial Infections ◽

Asymptomatic Bacteriuria ◽

Multidrug Resistant ◽

Resistance Rate ◽

First Line ◽

E Coli ◽

First Line Therapy ◽

Tract Infections

Urinary tract infections (UTIs) are among the most common bacterial infections in children, and Escherichia coli is the main pathogen responsible. Several guidelines, including the recently updated Italian guidelines, recommend amoxicillin-clavulanic acid (AMC) as a first-line antibiotic therapy in children with febrile UTIs. Given the current increasing rates of antibiotic resistance worldwide, this study aimed to investigate the three-year trend in the resistance rate of E. coli isolated from pediatric urine cultures (UCs) in a metropolitan area of northern Italy. We conducted a retrospective review of E. coli-positive, non-repetitive UCs collected in children aged from 1 month to 14 years, regardless of a diagnosis of UTI, catheter colonization, urine contamination, or asymptomatic bacteriuria. During the study period, the rate of resistance to AMC significantly increased from 17.6% to 40.2% (p < 0.001). Ciprofloxacin doubled its resistance rate from 9.1% to 16.3% (p = 0.007). The prevalence of multidrug-resistant E. coli rose from 3.9% to 9.2% (p = 0.015). The rate of resistance to other considered antibiotics remained stable, as did the prevalence of extended spectrum beta-lactamases and extensively resistant E. coli among isolates. These findings call into question the use of AMC as a first-line therapy for pediatric UTIs in our population, despite the indications of recent Italian guidelines.

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Molecular survey of mcr1 and mcr2 plasmid mediated colistin resistance genes in Escherichia coli isolates of animal origin in Iran

BMC Research Notes ◽

10.1186/s13104-021-05519-6 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Kayhan Ilbeigi ◽

Mahdi Askari Badouei ◽

Hossein Vaezi ◽

Hassan Zaheri ◽

Sina Aghasharif ◽

...

Keyword(s):

Escherichia Coli ◽

Resistance Genes ◽

Companion Animals ◽

Multidrug Resistant ◽

Animal Origin ◽

Colistin Resistance ◽

E Coli ◽

High Level ◽

Farming Industry

Abstract Objectives The emergence of colistin-resistant Enterobacteriaceae from human and animal sources is one of the major public health concerns as colistin is the last-resort antibiotic for treating infections caused by multidrug-resistant Gram-negative bacteria. We aimed to determine the prevalence of the prototype widespread colistin resistance genes (mcr-1 and mcr-2) among commensal and pathogenic Escherichia coli strains isolated from food-producing and companion animals in Iran. Results A total of 607 E. coli isolates which were previously collected from different animal sources between 2008 and 2016 used to uncover the possible presence of plasmid-mediated colistin resistance genes (mcr-1 and mcr-2) by PCR. Overall, our results could not confirm the presence of any mcr-1 or mcr-2 positive E. coli among the studied isolates. It is concluded that despite the important role of food-producing animals in transferring the antibiotic resistance, they were not the main source for carriage of mcr-1 and mcr-2 in Iran until 2016. This study suggests that the other mcr variants (mcr-3 to mcr-9) might be responsible for conferring colistin resistance in animal isolates in Iran. The possible linkage between pig farming industry and high level of mcr carriage in some countries needs to be clarified in future prospective studies.

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Comparative Genomics ofEscherichia coliIsolated from Skin and Soft Tissue and Other Extraintestinal Infections

mBio ◽

10.1128/mbio.01070-17 ◽

2017 ◽

Vol 8 (4) ◽

Cited By ~ 12

Author(s):

Amit Ranjan ◽

Sabiha Shaik ◽

Nishant Nandanwar ◽

Arif Hussain ◽

Sumeet K. Tiwari ◽

...

Keyword(s):

Escherichia Coli ◽

Comparative Genomics ◽

Soft Tissue ◽

Multidrug Resistant ◽

Primary Concern ◽

Beta Lactamase ◽

Soft Tissue Infections ◽

E Coli ◽

Recent Emergence ◽

Tract Infections

ABSTRACTEscherichia coli, an intestinal Gram-negative bacterium, has been shown to be associated with a variety of diseases in addition to intestinal infections, such as urinary tract infections (UTIs), meningitis in neonates, septicemia, skin and soft tissue infections (SSTIs), and colisepticemia. Thus, for nonintestinal infections, it is categorized as extraintestinal pathogenicE. coli(ExPEC). It is also an opportunistic pathogen, causing cross infections, notably as an agent of zoonotic diseases. However, comparative genomic data providing functional and genetic coordinates for ExPEC strains associated with these different types of infections have not proven conclusive. In the study reported here, ExPECE. coliisolated from SSTIs was characterized, including virulence and drug resistance profiles, and compared with isolates from patients suffering either pyelonephritis or septicemia. Results revealed that the majority of the isolates belonged to two pathogenic phylogroups, B2 and D. Approximately 67% of the isolates were multidrug resistant (MDR), with 85% producing extended-spectrum beta-lactamase (ESBL) and 6% producing metallo-beta-lactamase (MBL). TheblaCTX-M-15genotype was observed in at least 70% of theE. coliisolates in each category, conferring resistance to an extended range of beta-lactam antibiotics. Whole-genome sequencing and comparative genomics of the ExPEC isolates revealed that two of the four isolates from SSTIs, NA633 and NA643, belong to pandemic sequence type ST131, whereas functional characteristics of three of the ExPEC pathotypes revealed that they had equal capabilities to form biofilm and were resistant to human serum. Overall, the isolates from a variety of ExPEC infections demonstrated similar resistomes and virulomes and did not display any disease-specific functional or genetic coordinates.IMPORTANCEInfections caused by extraintestinal pathogenicE. coli(ExPEC) are of global concern as they result in significant costs to health care facilities management. The recent emergence of a multidrug-resistant pandemic clone,Escherichia coliST131, is of primary concern as a global threat. In developing countries, such as India, skin and soft tissue infections (SSTIs) associated withE. coliare marginally addressed. In this study, we employed both genomic analysis and phenotypic assays to determine relationships, if any, among the ExPEC pathotypes. Similarity between antibiotic resistance and virulence profiles was observed, ST131 isolates from SSTIs were reported, and genomic similarities among strains isolated from different disease conditions were detected. This study provides functional molecular infection epidemiology insight into SSTI-associatedE. colicompared with ExPEC pathotypes.

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Molecular Characterization of Plasmid-Mediated Non-O157 Verotoxigenic Escherichia coli Isolated from Infants and Children with Diarrhea

Baghdad Science Journal ◽

10.21123/bsj.2020.17.3.0710 ◽

2020 ◽

Vol 17 (3) ◽

pp. 0710

Author(s):

Md Fazlul Karim Khan ◽

Shah Samiur Rashid

Keyword(s):

Escherichia Coli ◽

Virulence Gene ◽

Multidrug Resistant ◽

Plasmid Curing ◽

Health Issues ◽

E Coli ◽

Disk Diffusion Assay ◽

Microbiological Techniques ◽

Polymerase Chain

A significant increase in the incidence of non-O157 verotoxigenic Escherichia coli (VTEC) infections have become a serious health issues, and this situation is worsening due to the dissemination of plasmid mediated multidrug-resistant microorganisms worldwide. This study aims to investigate the presence of plasmid-mediated verotoxin gene in non-O157 E. coli. Standard microbiological techniques identified a total of 137 E. coli isolates. The plasmid was detected by Perfectprep Plasmid Mini preparation kit. These isolates were subjected to disk diffusion assay, and plasmid curing with ethidium bromide treatment. The plasmid containing isolates were subjected to a polymerase chain reaction (PCR) for investigating the presence of plasmid mediated verotoxin gene (VT1 and VT2) in non-O157 E. coli. Among the 137 E. coli isolates, 49 isolates were non-O157 E. coli while 29 (59.1%) isolates were verotoxin producing non-O157 serotypes and 26 non-O157 VTEC isolates possessed plasmids. Certain isolates harboured single sized plasmid while others had multiple plasmids with different size varied from 1.8kb to 7.6kb. A plasmid containing all (100%) the isolates was multidrug-resistant. Eight isolates changed their susceptibility patterns while three isolates were found to lose plasmid after post plasmid curing treatment and the rest of the isolates (15) remained constant. Different PCR sets characterized 3 plasmid-mediated verotoxins producing non-O157 E. coli. This current study demonstrated the occurrence of plasmid mediated verotoxin gene in non-O157 E. coli. To the best of our knowledge, this is the first report in the global literature on plasmid-mediated verotoxin gene in non-O157 E. coli. Timely diagnosis and surveillance of VTEC infections should prioritize to stop or slow down the virulence gene for dissemination by plasmid-mediated gene transfer amongst the same bacteria or other species.

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Heterogeneous and Flexible Transmission ofmcr-1in Hospital-AssociatedEscherichia coli

mBio ◽

10.1128/mbio.00943-18 ◽

2018 ◽

Vol 9 (4) ◽

Cited By ~ 23

Author(s):

Yingbo Shen ◽

Zuowei Wu ◽

Yang Wang ◽

Rong Zhang ◽

Hong-Wei Zhou ◽

...

Keyword(s):

Escherichia Coli ◽

Genomic Analysis ◽

Multidrug Resistant ◽

Fluoroquinolone Resistance ◽

Gram Negative Bacteria ◽

Colistin Resistance ◽

Gram Negative ◽

Content Type ◽

E Coli ◽

Genes Encoding

ABSTRACTThe recent emergence of a transferable colistin resistance mechanism, MCR-1, has gained global attention because of its threat to clinical treatment of infections caused by multidrug-resistant Gram-negative bacteria. However, the possible transmission route ofmcr-1amongEnterobacteriaceaespecies in clinical settings is largely unknown. Here, we present a comprehensive genomic analysis ofEscherichia coliisolates collected in a hospital in Hangzhou, China. We found thatmcr-1-carrying isolates from clinical infections and feces of inpatients and healthy volunteers were genetically diverse and were not closely related phylogenetically, suggesting that clonal expansion is not involved in the spread ofmcr-1. Themcr-1gene was found on either chromosomes or plasmids, but in most of theE. coliisolates,mcr-1was carried on plasmids. The genetic context of the plasmids showed considerable diversity as evidenced by the different functional insertion sequence (IS) elements, toxin-antitoxin (TA) systems, heavy metal resistance determinants, and Rep proteins of broad-host-range plasmids. Additionally, the genomic analysis revealed nosocomial transmission ofmcr-1and the coexistence ofmcr-1with other genes encoding β-lactamases and fluoroquinolone resistance in theE. coliisolates. These findings indicate thatmcr-1is heterogeneously disseminated in both commensal and pathogenic strains ofE. coli, suggest the high flexibility of this gene in its association with diverse genetic backgrounds of the hosts, and provide new insights into the genome epidemiology ofmcr-1among hospital-associatedE. colistrains.IMPORTANCEColistin represents one of the very few available drugs for treating infections caused by extensively multidrug-resistant Gram-negative bacteria. The recently emergentmcr-1colistin resistance gene threatens the clinical utility of colistin and has gained global attention. Howmcr-1spreads in hospital settings remains unknown and was investigated by whole-genome sequencing ofmcr-1-carryingEscherichia coliin this study. The findings revealed extraordinary flexibility ofmcr-1in its spread among genetically diverseE. colihosts and plasmids, nosocomial transmission ofmcr-1-carryingE. coli, and the continuous emergence of novel Inc types of plasmids carryingmcr-1and newmcr-1variants. Additionally,mcr-1was found to be frequently associated with other genes encoding β-lactams and fluoroquinolone resistance. These findings provide important information on the transmission and epidemiology ofmcr-1and are of significant public health importance as the information is expected to facilitate the control of this significant antibiotic resistance threat.

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Molecular characterization of Escherichia coli isolates from patients with urinary tract infections in Palestine

Journal of Medical Microbiology ◽

10.1099/jmm.0.067140-0 ◽

2014 ◽

Vol 63 (2) ◽

pp. 229-234 ◽

Cited By ~ 16

Author(s):

Kamel Adwan ◽

Naser Jarrar ◽

Awni Abu-Hijleh ◽

Ghaleb Adwan ◽

Elena Awwad

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Enterobacterial Repetitive Intergenic Consensus ◽

The West ◽

E Coli ◽

Amoxicillin Clavulanic Acid ◽

Tract Infections ◽

Resistance Rates

Antibiotic resistance of Escherichia coli isolated from urinary tract infections (UTIs) is increasing worldwide. A total of 41 E. coli isolates were obtained from urine samples from hospitalized patients with a UTI in three hospitals in the northern districts of the West Bank, Palestine during March and June 2011. Resistance rates were: erythromycin (95 %), trimethoprim–sulfamethoxazole (59 %), ciprofloxacin (56 %), gentamicin (27 %), imipenem (22 %), amoxicillin (93 %), amoxicillin–clavulanic acid (32 %), ceftazidime (66 %) and cefotaxime (71 %). No meropenem-resistant isolates were identified in this study. Among the isolates, phylogenetic group B2 was observed in 13 isolates, D in 12 isolates, A in 11 isolates and B1 in five isolates. Thirty-five of the isolates were positive for an extended-spectrum β-lactamase phenotype. Among these isolates, the bla CTX-M gene was detected in 25, and eight harboured the bla TEM gene. None of the isolates contained the bla SHV gene. Transformation experiments indicated that some of the β-lactamase genes (i.e. bla CTX-M and bla TEM) with co-resistance to erythromycin and gentamicin were plasmid encoded and transmissible. Apart from this, enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) revealed that the 41 isolates were genetically diverse and comprised a heterogeneous population with 11 ERIC-PCR profiles at a 60 % similarity level.

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Characterization of Multidrug-Resistant Escherichia coli Isolates from Animals Presenting at a University Veterinary Hospital

Applied and Environmental Microbiology ◽

10.1128/aem.00599-11 ◽

2011 ◽

Vol 77 (20) ◽

pp. 7104-7112 ◽

Cited By ~ 59

Author(s):

Maria Karczmarczyk ◽

Yvonne Abbott ◽

Ciara Walsh ◽

Nola Leonard ◽

Séamus Fanning

Keyword(s):

Escherichia Coli ◽

Molecular Mechanisms ◽

Gene Array ◽

Multidrug Resistant ◽

Genetic Determinants ◽

Gene Encoding ◽

Content Type ◽

E Coli ◽

Class 1

ABSTRACTIn this study, we examined molecular mechanisms associated with multidrug resistance (MDR) in a collection ofEscherichia coliisolates recovered from hospitalized animals in Ireland. PCR and DNA sequencing were used to identify genes associated with resistance. Class 1 integrons were prevalent (94.6%) and contained gene cassettes recognized previously and implicated mainly in resistance to aminoglycosides, β-lactams, and trimethoprim (aadA1,dfrA1-aadA1,dfrA17-aadA5,dfrA12-orfF-aadA2,blaOXA-30-aadA1,aacC1-orf1-orf2-aadA1,dfr7). Class 2 integrons (13.5%) contained thedfrA1-sat1-aadA1gene array. The most frequently occurring phenotypes included resistance to ampicillin (97.3%), chloramphenicol (75.4%), florfenicol (40.5%), gentamicin (54%), neomycin (43.2%), streptomycin (97.3%), sulfonamide (98.6%), and tetracycline (100%). The associated resistance determinants detected includedblaTEM,cat,floR,aadB,aphA1,strA-strB,sul2, andtet(B), respectively. TheblaCTX-M-2gene, encoding an extended-spectrum β-lactamase (ESβL), andblaCMY-2, encoding an AmpC-like enzyme, were identified in 8 and 18 isolates, respectively. The mobility of the resistance genes was demonstrated using conjugation assays with a representative selection of isolates. High-molecular-weight plasmids were found to be responsible for resistance to multiple antimicrobial compounds. The study demonstrated that animal-associated commensalE. coliisolates possess a diverse repertoire of transferable genetic determinants. Emergence of ESβLs and AmpC-like enzymes is particularly significant. To our knowledge, theblaCTX-M-2gene has not previously been reported in Ireland.

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Phenotypic and Molecular Detection of Resistance Genes from Multi-drug Resistant Escherichia coli Isolated from Patients Attending Selected Hospitals in Damaturu, Yobe State, Nigeria

International Journal of Research and Review ◽

10.52403/ijrr.20210951 ◽

2021 ◽

Vol 8 (9) ◽

pp. 396-407

Author(s):

Sheriff Wakil ◽

Mustafa Alhaji Isa ◽

Adam Mustapa

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Resistance Genes ◽

Molecular Detection ◽

Multidrug Resistant ◽

Clinical Samples ◽

E Coli ◽

Resistant Genes ◽

Tract Infections

Multidrug resistance among Escherichia coli causing urinary tract infections (UTIs) and diarrhea are major public health problem worldwide which cause difficulty in treating the infections caused by Escherichia coli due to the high resistances. The study is aimed to determine the phenotypic and molecular detection of multidrug resistant E. coli isolated from clinical samples of patients attending selected Hospitals in Damaturu, Yobe State-Nigeria. Methods: Two hundred (200) clinical samples were collected aseptically from patient diagnosed with (100 stool samples) and UTI’s (100 urine samples) using sterile universal container. The samples were processed using standard microbiological methods for identification of E. coli. Samples were cultured on MacConkey agar (stool) and Cystine lactose electrolyte deficient agar (urine). The resulting colonies of isolates were further subculture on Eosin methylene blue agar for confirmatory and followed by gram stain, biochemical identification at Microbiology laboratory unit of Yobe State Specialist and Yobe State Teaching Hospital respectively. The antimicrobial susceptibility patterns were determined using Kirby-Bauer disc diffusion techniques and the phenotypic expression of extended spectrum beta-lactamases (ESBLs) were determined using modified double disc synergy test (MDDST) and also the three (3) resistance genes (blaTEM, accC1 and qnrA) were detected using polymerase chain reaction. Results: One hundred and twenty-two (122) isolates were resistant to antibiotics. The highest level of resistance was against amoxicillin (90.2%) while the least resistance was against sparfloxacin (24.3%). Thirty-seven (37) E. coli isolates shows MDR; the highest MDR was (24.3%) while least MDR was (5.4%). The PCR amplification of resistant genes (blaTEM, accC1 and qnrA) were detected on E. coli that shows positive ESBL and the bands were separated using agarose gel electrophoresis. Conclusion: The findings of this study show augmentin, ciprofloxacin and sparfloxacin are the most effective antibiotics against E. coli isolated from patients attending the two hospitals in Damaturu; who are diagnose with UTI and diarrheic infection. The resistant genes include; blaTEM, accC1 and qnrA coding for beta-lactam, aminoglycoside and quinolones were present in E. coli isolated from patients attending selected Hospitals in Yobe State, Nigeria. Keywords: Multidrug resistant, Escherichia coli, extended spectrum beta lactamase, resistance-associated genes, urinary tract infections, diarrheic.

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Molecular Detection of Colistin Resistance mcr-1 Gene in Multidrug-Resistant Escherichia coli Isolated from Chicken

Antibiotics ◽

10.3390/antibiotics11010097 ◽

2022 ◽

Vol 11 (1) ◽

pp. 97

Author(s):

Md Bashir Uddin ◽

Mohammad Nurul Alam ◽

Mahmudul Hasan ◽

S. M. Bayejed Hossain ◽

Mita Debnath ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Agents ◽

Catalytic Domain ◽

Phylogenetic Analyses ◽

Multidrug Resistant ◽

Sequencing Analysis ◽

Global Public Health ◽

Colistin Resistance ◽

E Coli ◽

Chicken Feces

Zoonotic and antimicrobial-resistant Escherichia coli (hereafter, E. coli) is a global public health threat which can lead to detrimental effects on human health. Here, we aim to investigate the antimicrobial resistance and the presence of mcr-1 gene in E. coli isolated from chicken feces. Ninety-four E. coli isolates were obtained from samples collected from different locations in Bangladesh, and the isolates were identified using conventional microbiological tests. Phenotypic disk diffusion tests using 20 antimicrobial agents were performed according to CLSI-EUCAST guidelines, and minimum inhibitory concentrations (MICs) were determined for a subset of samples. E. coli isolates showed high resistance to colistin (88.30%), ciprofloxacin (77.66%), trimethoprim/sulfamethoxazole (76.60%), tigecycline (75.53%), and enrofloxacin (71.28%). Additionally, the pathotype eaeA gene was confirmed in ten randomly selected E. coli isolates using primer-specific polymerase chain reaction (PCR). The presence of mcr-1 gene was confirmed using PCR and sequencing analysis in six out of ten E. coli isolates. Furthermore, sequencing and phylogenetic analyses revealed a similarity between the catalytic domain of Neisseria meningitidis lipooligosaccharide phosphoethanolamine transferase A (LptA) and MCR proteins, indicating that the six tested isolates were colistin resistant. Finally, the findings of the present study showed that E. coli isolated from chicken harbored mcr-1 gene, and multidrug and colistin resistance. These findings accentuate the need to implement strict measures to limit the imprudent use of antibiotics, particularly colistin, in agriculture and poultry farms.

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