Complete DNA Sequence of a ColBM Plasmid from Avian Pathogenic Escherichia coli Suggests that It Evolved from Closely Related ColV Virulence Plasmids

ABSTRACT Avian pathogenic Escherichia coli (APEC), an extraintestinal pathogenic E. coli causing colibacillosis in birds, is responsible for significant economic losses for the poultry industry. Recently, we reported that the APEC pathotype was characterized by possession of a set of genes contained within a 94-kb cluster linked to a ColV plasmid, pAPEC-O2-ColV. These included sitABCD, genes of the aerobactin operon, hlyF, iss, genes of the salmochelin operon, and the 5′ end of cvaB of the ColV operon. However, the results of gene prevalence studies performed among APEC isolates revealed that these traits were not always linked to ColV plasmids. Here, we present the complete sequence of a 174-kb plasmid, pAPEC-O1-ColBM, which contains a putative virulence cluster similar to that of pAPEC-O2-ColV. These two F-type plasmids share remarkable similarity, except that they encode the production of different colicins; pAPEC-O2-ColV contains an intact ColV operon, and pAPEC-O1-ColBM encodes the colicins B and M. Interestingly, remnants of the ColV operon exist in pAPEC-O1-ColBM, hinting that ColBM-type plasmids may have evolved from ColV plasmids. Among APEC isolates, the prevalence of ColBM sequences helps account for the previously observed differences in prevalence between genes of the “conserved” portion of the putative virulence cluster of pAPEC-O2-ColV and those genes within its “variable” portion. These results, in conjunction with Southern blotting and probing of representative ColBM-positive strains, indicate that this “conserved” cluster of putative virulence genes is primarily linked to F-type virulence plasmids among the APEC isolates studied.

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Virulence gene profiles of avian pathogenic Escherichia coli isolated from chickens with colibacillosis in Bulawayo, Zimbabwe

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v82i1.850 ◽

2015 ◽

Vol 82 (1) ◽

Cited By ~ 10

Author(s):

Joshua Mbanga ◽

Yvonne O. Nyararai

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Virulence Gene ◽

Economic Losses ◽

Avian Pathogenic Escherichia Coli ◽

Pcr Assay ◽

E Coli ◽

Gene Profiles ◽

Pathogenic Escherichia Coli ◽

Polymerase Chain

Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC), is one of the main causes of economic losses in the poultry industry worldwide. This study was carried out in order to determine the APEC-associated virulence genes contained by E. coli isolates causing colibacillosis in chickens. A total of 45 E. coli isolates were obtained from the diagnostics and research branch of the Central Veterinary Laboratories, Bulawayo, Zimbabwe. These isolates were obtained from chickens with confirmed cases of colibacillosis after postmortem examination. The presence of the iutA, hlyF, ompT, frz, sitD, fimH, kpsM, sitA, sopB, uvrY, pstB and vat genes were investigated by multiplex polymerase chain reaction (PCR) assay. Of the 45 isolates, 93% were positive for the presence of at least one virulence gene. The three most prevalent virulence genes were iutA (80%), fimH (33.3%) and hlyF (24.4%). The kpsM, pstB and ompT genes had the lowest prevalence, having been detected in only 2.2% of the isolates. All 12 virulence genes studied were detected in the 45 APEC isolates. Virulence gene profiles were constructed for each APEC isolate from the multiplex data. The APEC isolates were profiled as 62.2% fitting profile A, 31.1% profile B and 6.7% profile C. None of the isolates had more than seven virulence genes. Virulence profiles of Zimbabwean APEC isolates are different from those previously reported. Zimbabwean APEC isolates appear to be less pathogenic and may rely on environmental factors and stress in hosts to establish infection.

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IDENTIFICATION OF THE AVIAN PATHOTYPE OF ESCHERICHIA COLI ON LAYER FLOCKS BY MULTIPLEX PCR

CBU International Conference Proceedings ◽

10.12955/cbup.v7.1473 ◽

2019 ◽

Vol 7 ◽

pp. 905-911

Author(s):

Marilena Burtan ◽

Virgilia Popa ◽

Maria Rodica Gurau ◽

Doina Danes

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Virulence Genes ◽

Virulence Gene ◽

Economic Losses ◽

Ompa Gene ◽

Avian Pathogenic Escherichia Coli ◽

E Coli ◽

Pathogenic Escherichia Coli

Introduction: Colibacillosis in poultry is determined by avian pathogenic Escherichia coli (APEC) and represents an important source of economic losses in the poultry industry. APEC’s pathogenicity relies on the presence and expression of different virulence factors. The genes ompA , iss and fimH, encoding the outer membrane protein, the protein inducing resistance to complement and the synthesis of type 1 fimbria are present in APEC strains. Objective: Escherichia coli strains isolated from layers were analysed to assess the pathotype they belong to. Methods: In order to detect the three genes associated with APEC strains, 16 E. coli isolates were investigated for virulence associated genes ompA, iss and fimH, using multiplex PCR. Results: From the 16 E.coli strains submitted, multiplex PCR assessment revealed that 14 (87.5%) of the E. coli strains isolated contained at least one virulence gene, while 2 (12.5%) strains did not harbour any of the virulence genes tested. The fimH gene was noted in 13 (81.25%) of the strains tested, the ompA gene has been present in 12 (75%) strains and the iss gene was present in 9 (56.25%) strains. Eight (50%) strains were found to present all three investigated genes. Conclusion: Presence of these genes is a strong indicatory to consider those strains as belonging to the APEC pathotype.

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Specific Roles of the iroBCDEN Genes in Virulence of an Avian Pathogenic Escherichia coli O78 Strain and in Production of Salmochelins

Infection and Immunity ◽

10.1128/iai.00455-08 ◽

2008 ◽

Vol 76 (8) ◽

pp. 3539-3549 ◽

Cited By ~ 65

Author(s):

Mélissa Caza ◽

François Lépine ◽

Sylvain Milot ◽

Charles M. Dozois

Keyword(s):

Escherichia Coli ◽

Respiratory Infections ◽

Mass Spectrometry Analysis ◽

Liquid Chromatography Mass Spectrometry ◽

Avian Pathogenic Escherichia Coli ◽

Prevalence Studies ◽

Spectrometry Analysis ◽

E Coli ◽

Pathogenic Escherichia Coli ◽

Negative Mutant

ABSTRACT Avian pathogenic Escherichia coli (APEC) strains are a subset of extraintestinal pathogenic E. coli (ExPEC) strains associated with respiratory infections and septicemia in poultry. The iroBCDEN genes encode the salmochelin siderophore system present in Salmonella enterica and some ExPEC strains. Roles of the iro genes for virulence in chickens and production of salmochelins were assessed by introducing plasmids carrying different combinations of iro genes into an attenuated salmochelin- and aerobactin-negative mutant of O78 strain χ7122. Complementation with the iroBCDEN genes resulted in a regaining of virulence, whereas the absence of iroC, iroDE, or iroN abrogated restoration of virulence. The iroE gene was not required for virulence, since introduction of iroBCDN restored the capacity to cause lesions and colonize extraintestinal tissues. Prevalence studies indicated that iro sequences were associated with virulent APEC strains. Liquid chromatography-mass spectrometry analysis of supernatants of APEC χ7122 and the complemented mutants indicated that (i) for χ7122, salmochelins comprised 14 to 27% of the siderophores present in iron-limited medium or infected tissues; (ii) complementation of the mutant with the iro locus increased levels of glucosylated dimers (S1 and S5) and monomer (SX) compared to APEC strain χ7122; (iii) the iroDE genes were important for generation of S1, S5, and SX; (iv) iroC was required for export of salmochelin trimers and dimers; and (v) iroB was required for generation of salmochelins. Overall, efficient glucosylation (IroB), transport (IroC and IroN), and processing (IroD and IroE) of salmochelins are required for APEC virulence, although IroE appears to serve an ancillary role.

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Bacteriophage activity against and characterisation of avian pathogenic Escherichia coli isolated from colibacillosis cases in Uganda

PLoS ONE ◽

10.1371/journal.pone.0239107 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0239107

Author(s):

George Kazibwe ◽

Phionah Katami ◽

Ruth Alinaitwe ◽

Stephen Alafi ◽

Ann Nanteza ◽

...

Keyword(s):

Escherichia Coli ◽

Host Range ◽

Bacterial Infections ◽

Virulence Genes ◽

Virulence Gene ◽

Economic Losses ◽

Multi Drug Resistance ◽

Avian Pathogenic Escherichia Coli ◽

Alternative Strategies ◽

Pathogenic Escherichia Coli

Avian Pathogenic Escherichia coli (APEC) cause colibacillosis leading to significant economic losses in the poultry industry. This laboratory-based study aimed at establishing stocks of avian pathogenic Escherichia coli lytic bacteriophages, for future development of cocktail products for colibacillosis management. The study determined the antibiotic susceptibility; phylogenetic categories, occurrence of selected serotypes and virulence genes among Escherichia coli stock isolates from chicken colibacillosis cases; and evaluated bacteriophage activity against the bacteria. Escherichia coli characterization was done through phenotypic and multiplex PCR methods. Bacteriophage isolation and preliminary characterization was achieved using the spot assay and overlay plating techniques. Fifty-six (56) isolates were phenotypically confirmed as E. coli and all exhibited resistance to at least one antimicrobial agent; while multi-drug resistance (at least three drugs) was encountered in 50 (89.3%) isolates. The APEC isolates mainly belonged to phylogroups A and D, representing 44.6% and 39.3%, respectively; whereas serotypes O1, O2 and O78 were not detected. Of the 56 isolates, 69.6% harbored at least one virulence gene, while 50% had at least four virulence genes; hence confirmed as APEC. Virulence genes, ompT and iutA were the most frequent in 33 (58.9%) and 32 (57.1%) isolates respectively; while iroN least occurred in 23 (41.1%) isolates. Seven lytic bacteriophages were isolated and their host range, at 1×108 PFU/ml, varied from 1.8% to 17.9% of the 56 APEC isolates, while the combined lytic spectrum was 25%. Phage stability was negatively affected by increasing temperatures with both UPEC04 and UPEC10 phages being undetectable at 70°C; whereas activity was detected between pH 2 and 12. The high occurrence of APEC isolates resistant against the commonly used antibiotics supports the need for alternative strategies of bacterial infections control in poultry. The low host range exhibited by the phages necessitates search for more candidates before in-depth phage characterization and application.

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Virulence-Associated Gene Profiles of Avian Pathogenic Escherichia coli Isolated From Broilers With Colibacillosis: A Pilot Study in Iran

International Journal of Enteric Pathogens ◽

10.15171/ijep.2019.02 ◽

2019 ◽

Vol 7 (1) ◽

pp. 4-8

Author(s):

Payam Haghighi Khoshkhoo ◽

Hadi Pourtaghi ◽

Gita Akbariazad ◽

Saeed Mokhayeri

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Economic Losses ◽

Avian Pathogenic Escherichia Coli ◽

Chain Reaction ◽

Biochemical Tests ◽

Gene Profiles ◽

Pathogenic Escherichia Coli ◽

Poultry Farms ◽

Polymerase Chain

Background: Avian pathogenic Escherichia coli (APEC) causes economic losses in the chicken industry worldwide. Objective: In this study, virulence-associated gene profiles of APEC isolates were investigated by polymerase chain reaction (PCR). Materials and Methods: A total of 60 Escherichia coli isolates were collected from 60 colibacillosis cases from 30 broiler poultry farms in Alborz, Tehran, and Golestan provinces, Iran. After identification by biochemical tests, DNA was extracted by boiling method and 5 virulence-associated genes including: iutA, hlyF, iroN, ompT, and iss were detected by 2 multiplex PCR protocols. Results: Of the 60 APEC isolates, 26 (43.3%) isolates had at least three virulence genes from which 12 (20%) isolates were positive for all 5 virulence genes, whereas 34 (56.6%) carried no investigated virulence genes. Presence of iutA, hlyF, iroN, ompT, and iss genes in the APEC isolates were 17 (28.3%), 17 (28.3%), 24 (40%), 26 (43.3%), and 23 (38.3%), respectively. Conclusion: According to the results, four different virulence-associated gene profiles were seen in isolates, from which profile 1 with 12 (20%) isolates was predominant. These findings were in agreement with the previous reports.

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Multidrug-Resistant Avian Pathogenic Escherichia coli Strains and Association of Their Virulence Genes in Bangladesh

Microorganisms ◽

10.3390/microorganisms8081135 ◽

2020 ◽

Vol 8 (8) ◽

pp. 1135

Author(s):

Otun Saha ◽

M. Nazmul Hoque ◽

Ovinu Kibria Islam ◽

Md. Mizanur Rahaman ◽

Munawar Sultana ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Multidrug Resistant ◽

Avian Pathogenic Escherichia Coli ◽

E Coli ◽

Molecular Approaches ◽

Clade B ◽

Pathogenic Escherichia Coli ◽

Resistance Patterns

The avian pathogenic Escherichia coli (APEC) strains are the chief etiology of colibacillosis worldwide. The present study investigated the circulating phylotypes, existence of virulence genes (VGs), and antimicrobial resistance (AMR) in 392 APEC isolates, obtained from 130 samples belonged to six farms using both phenotypic and PCR-based molecular approaches. Congo red binding (CRB) assay confirmed 174 APEC isolates which were segregated into ten, nine, and eight distinct genotypes by RAPD assay (discriminatory index, DI = 0.8707), BOX-PCR (DI = 0.8591) and ERIC-PCR (DI = 0.8371), respectively. The combination of three phylogenetic markers (chuA, yjaA and DNA fragment TspE4.C2) classified APEC isolates into B23 (37.36%), A1 (33.91%), D2 (11.49%), B22 (9.20%), and B1 (8.05%) phylotypes. Majority of the APEC isolates (75–100%) harbored VGs (ial, fimH, crl, papC, and cjrC). These VGs (papC and cjrC) and phylotypes (D2 and B2) of APEC had significant (p = 0.004) association with colibacillosis. Phylogenetic analysis showed two distinct clades (clade A and clade B) of APEC, where clade A had 98–100% similarity with E. coli APEC O78 and E. coli EHEC strains, and clade B had closest relationship with E. coli O169:H41 strain. Interestingly, phylogroups B2 and D2 were found in the APEC strains of both clades, while the strains from phylogroups A1 and B1 were found in clade A only. In this study, 81.71% of the isolates were biofilm formers, and possessed plasmids of varying ranges (1.0 to 54 kb). In vitro antibiogram profiling revealed that 100% isolates were resistant to ≥3 antibiotics, of which 61.96%, 55.24%, 53.85%, 51.16% and 45.58% isolates in phylotypes B1, D2, B22, B23, and A1, respectively, were resistant to these antimicrobials. The resistance patterns varied among different phylotypes, notably in phylotype B22, showing the highest resistance to ampicillin (90.91%), nalidixic acid (90.11%), tetracycline (83.72%), and nitrofurantoin (65.12%). Correspondence analysis also showed significant correlation among phylotypes with CRB (p = 0.008), biofilm formation (p = 0.02), drug resistance (p = 0.03), and VGs (p = 0.06). This report demonstrated that B2 and A1 phylotypes are dominantly circulating APEC phylotypes in Bangladesh; however, B2 and D2 are strongly associated with the pathogenicity. A high prevalence of antibiotic-resistant APEC strains from different phylotypes suggest the use of organic antimicrobial compounds, and/or metals, and the rotational use of antibiotics in poultry farms in Bangladesh.

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Antibiotic Resistance and Virulence Gene Patterns Associated with Avian Pathogenic Escherichia coli from Broiler Chickens in Qatar

10.29117/quarfe.2021.0102 ◽

2021 ◽

Author(s):

Alreem Johar ◽

Najlaa Al-Thani ◽

Sara Al-Hadidi ◽

Elyes Dlissi ◽

Mahmoud Mahoud ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Broiler Chickens ◽

Virulence Genes ◽

Virulence Gene ◽

Avian Pathogenic Escherichia Coli ◽

Chi Square ◽

E Coli ◽

Pathogenic Escherichia Coli ◽

Special Programs

Introduction: Avian Pathogenic Escherichia coli (APEC) is the contributing agent behind the avian infectious disease colibacillosis, which causes substantial fatalities in poultry industries that significantly impact the economy and food safety. Several virulence genes have been shown to be concomitant with the extra-intestinal survival of APEC. This study investigates the antibiotic resistance patterns and APEC‐associated virulence genes content in Escherichia coli (E. coli) isolated from non‐healthy and healthy broiler chickens from a commercial poultry farm in Qatar. Material and Methods: 158 E. coli strains were isolated from 47 chickens from five different organs (air sac, cloacal, kidney, liver, and trachea). Genomic DNA was extracted from E. coli using the QIAamp Pathogen Mini Kit. Multiplex PCR was executed to detect tsh, iucD, ompT, hlyF, iroN, iss, vat, cvi/cva genes associated with PPEC. Antibiotic susceptibility testing was performed using the standard Kirby-Bauer disk and E-test. Amplified virulence genes detected were sequenced and analyzed. Graph Pad version 8 and PAST software version 4.03 were used for statistical and clustering analysis. The chi-square test was performed on all data to compare the antibiotic resistance and virulence gene patterns between non-healthy and healthy chicken samples Results: 65% of the isolated bacteria were APEC strains containing five or more virulence genes, and 34% were non‐pathogenic E. coli (NPEC) strains. The genes ompT, hlyF, iroN, tsh, vat, iss, cvi/cva, and iucD were significantly prevalent in all APEC strains. E. coli isolates showed 96% resistance to at least one of the 18 antibiotics, with high resistance to ampicillin, cephalothin, ciprofloxacin, tetracycline, and fosfomycin. Conclusions: Our findings indicate high antibiotic resistance prevalence in non-healthy and healthy chicken carcasses. Such resistant E. coli can spread to humans. Hence, special programs are required to monitor the use of antibiotics in chicken production in Qatar.

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Virulence factors and antibiotic resistance of avian pathogenic Escherichia coli in eastern China

Journal of Veterinary Research ◽

10.2478/jvetres-2019-0056 ◽

2019 ◽

Vol 63 (3) ◽

pp. 317-320 ◽

Cited By ~ 1

Author(s):

Xiaojing Xu ◽

Qing Sun ◽

Lixiang Zhao

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Virulence Factors ◽

Virulence Genes ◽

Eastern China ◽

Economic Losses ◽

Avian Pathogenic Escherichia Coli ◽

Phylogenetic Groups ◽

Important Data ◽

Pathogenic Escherichia Coli

Abstract Introduction Avian pathogenicEscherichia coli (APEC) causes serious colibacillosis and significant economic losses. Data on profiles of virulence factors and antibiotic resistances among APEC strains are crucial to the control of infection. In this study, strains were isolated from eastern China, and the prevalence of virulence factors and distribution of antibiotic resistance were determined. Material and Methods APEC strains were isolated and characterised by PCR for O serogroups, virulence factor genes, antibiotic resistance, and phylogenetic groups. Results O78 was the most prevalent serogroup and type A was the most frequent phylogenetic group. ThefimH,feoB, andiron genes were the most prevalent among the isolates. All isolates were multiresistant, and all strains were resistant to ampicillin and tetracycline, which are widely used in the poultry industry in China. Conclusion This study provided important data on the presence of virulence genes and antibiotic resistance profiles of APEC from poultry farms in eastern China.

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Genomic analysis of avian-pathogenic Escherichia coli (APEC) isolated from diseased chicken

10.21203/rs.2.13990/v1 ◽

2019 ◽

Author(s):

Aneta Papoušková ◽

Martina Masaříková ◽

Adam Valček ◽

David Šenk ◽

Darina Čejková ◽

...

Keyword(s):

Escherichia Coli ◽

Economic Losses ◽

Zoonotic Potential ◽

Beta Lactamase ◽

Avian Pathogenic Escherichia Coli ◽

Phylogenetic Groups ◽

E Coli ◽

Molecular Features ◽

Local Spread ◽

Pathogenic Escherichia Coli

Abstract Background Avian pathogenic Escherichia coli (APEC) can cause various extraintestinal infections in chicken, resulting in massive economic losses in poultry industry. Apart from that, some avian E. coli strains may have zoonotic potential, making poultry a possible source of infection for humans. Due to its extreme genetic diversity, this pathotype remains poorly defined. This study aimed to investigate the diversity of colibacillosis-associated E. coli isolates from Central European countries with a focus on the Czech Republic.Results Out of 95 preliminarily characterized clinical isolates 32 isolates were selected for whole-genome sequencing. A multiresistant phenotype was detected in a majority of them and the predominant resistance to lactams and quinolones was widely associated with TEM-type beta-lactamase genes and chromosomal gyrA mutations, respectively. The phylogenetic analysis confirmed a great diversity of isolates, that were derived from nearly all phylogenetic groups, with predominace of B2, B1 and C phylogroups. Clusters of closely related isolates within ST23 (phylogroup C) and ST429 (phylogroup B2) indicated a long-term local spread of these clones. Besides, the ST429 cluster carried bla CMY-2, -59 genes for AmpC beta-lactamase and isolates of both clusters were generally well-equipped with virulence-associated genes, with considerable differences in distribution of certain virulence-associated genes between phylogenetically distant lineages. Other important and potentially zoonotic APEC STs were detected, incl. ST117, ST354 and ST95, showing several molecular features typical for human ExPEC.Conclusions The results support the concept of local spread of virulent APEC clones, as well as of zoonotic potential of specific poultry-associated lineages, and highlight the need to investigate the possible source of these pathogenic strains.

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Molecular profile of avian pathogenic Escherichia coli (APEC) from poultry associated with colibacillosis in Algeria

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.23666 ◽

2020 ◽

Vol 71 (2) ◽

pp. 2113

Author(s):

M. LOUNIS ◽

G. ZHAO ◽

Y. LI ◽

Y. GAO ◽

J. WANG ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Molecular Profile ◽

Avian Pathogenic Escherichia Coli ◽

Highly Pathogenic ◽

E Coli ◽

Pathogenic Escherichia Coli ◽

Six Genes

The objective of the present study was the detection of virulence-associated genes of E. coli isolated from chicken with colibacillosis. Seventeen (17) APEC isolates were examined by two panels of PCRs for the presence of 11 genes described for avian pathogenic (hlyF, iroN, iss, ompT, iutA and fimC) and diarrheagenic (eae, stx, est, elt, ipaH and aggR) E. coli. Results revealed that none of the APEC isolates harbored the genes eae, stx, est, elt, ipaH and aggR. In another hand, 88.2% of the isolates were positive for 3 or more of the virulence genes hlyF, iroN, iss, ompT, iutA and fimC. Also, 35.3% of the isolates harbored all the six genes. Genes fimC (88.2%), iss (82.3%) and ompT (76.5%) were the most prevalent while genes hylF, iutA and iroN which were present with the same frequency (52.9%) were mostly associated with highly pathogenic strains.

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