1
|
Delago J, Miller EA, Flores-Figueroa C, Munoz-Aguayo J, Cardona C, Smith AH, Johnson TJ. Survey of clinical and commensal Escherichia coli from commercial broilers and turkeys, with emphasis on high-risk clones using APECTyper. Poult Sci 2023; 102:102712. [PMID: 37156077 DOI: 10.1016/j.psj.2023.102712] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 04/09/2023] [Indexed: 05/10/2023] Open
Abstract
Molecular characterization of avian pathogenic Escherichia coli (APEC) is challenging due to the complex nature of its associated disease, colibacillosis, in poultry. Numerous efforts have been made toward defining APEC, and it is becoming clear that certain clonal backgrounds are predictive of an avian E. coli isolate's virulence potential. Thus, APEC can be further differentiated as high-risk APEC based upon their clonal background's virulence potential. However, less clear is the degree of overlap between clinical isolates of differing bird type, and between clinical and gastrointestinal isolates. This study aimed to determine genomic similarities and differences between such populations, comparing commercial broiler vs. turkey isolates, and clinical vs. gastrointestinal isolates. Differences were observed in Clermont phylogenetic groups between isolate populations, with B2 as the dominant group in turkey clinical isolates and G as the dominant group in broiler clinical isolates. Nearly all clinical isolates were classified as APEC using a traditional gene-based typing scheme, whereas 53.4% and 44.1% of broiler and turkey gastrointestinal isolates were classified as APEC, respectively. High-risk APEC were identified among 31.0% and 46.9% of broiler and turkey clinical isolates, compared with 5.7% and 2.9% of broiler and turkey gastrointestinal isolates. As found in previous studies, no specific known virulence or fitness gene sets were identified which universally differentiate between clinical and gastrointestinal isolates. This study further demonstrates the utility of a hybrid APEC typing approach, considering both plasmid content and clonal background, for the identification of dominant and highly virulent APEC clones in poultry production.
Collapse
Affiliation(s)
- Jodi Delago
- Arm and Hammer Animal and Food Production, Waukesha, WI, 53186, USA
| | - Elizabeth A Miller
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, USA
| | | | | | - Carol Cardona
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, USA
| | | | - Timothy J Johnson
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, USA; Mid-Central Research and Outreach Center, University of Minnesota, Willmar, MN, USA.
| |
Collapse
|
2
|
Molecular Detection of Complement Resistance Genes (traT and iss) in some Enterobacteriaceae Isolates. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2018. [DOI: 10.22207/jpam.12.4.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
3
|
Gao J, Duan X, Li X, Cao H, Wang Y, Zheng SJ. Emerging of a highly pathogenic and multi-drug resistant strain of Escherichia coli causing an outbreak of colibacillosis in chickens. INFECTION GENETICS AND EVOLUTION 2018; 65:392-398. [PMID: 30157463 DOI: 10.1016/j.meegid.2018.08.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 08/08/2018] [Accepted: 08/24/2018] [Indexed: 10/28/2022]
Abstract
Extraintestinal pathogenic Escherichia coli (ExPEC) are important human pathogens responsible for urinary tract infection and meningitis. Therefore, infection of chickens by highly pathogenic E. coli with multi-drug resistance has become a major concern to food safety. In this study, we isolated a strain of E. coli (HB2016) from the oviduct of a diseased chicken with colibacillosis. Inoculation of chickens with 2 × 106 CFU of the isolate E. coli HB2016 by intraperitoneal injection successfully reproduced colibacillosis in chickens. We also found that E. coli HB2016 harbored four more virulence genes (tsh, trat, cvaC and cvaA/B) than E. coli reference strain CVCC1428. Importantly, E. coli HB2016 was resistant to cefuroxime, tobramycin, medemycin, cefazolin, cefoperazone, streptomycin and ampicillin, and carried multiple antibiotic resistance genes such as strA, strB, blaCMY-2, blaCTX-M-19, blaTEM-1B, fosA, mph(A), floR, sul2, tet(A) and tet(B). These findings suggest that the causative E. coli act as a potential zoonotic agent affecting human health.
Collapse
Affiliation(s)
- Junfeng Gao
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China; College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Xueyan Duan
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China; College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Xiaoqi Li
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China; College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Hong Cao
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China; College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yongqiang Wang
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China; College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
| | - Shijun J Zheng
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China; College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
| |
Collapse
|
4
|
Escherichia coli isolates from patients with inflammatory bowel disease: ExPEC virulence- and colicin-determinants are more frequent compared to healthy controls. Int J Med Microbiol 2018; 308:498-504. [PMID: 29735381 DOI: 10.1016/j.ijmm.2018.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 04/04/2018] [Accepted: 04/30/2018] [Indexed: 12/12/2022] Open
Abstract
A set of 178 Escherichia coli isolates taken from patients with inflammatory bowel disease (IBD) was analyzed for bacteriocin production and tested for the prevalence of 30 bacteriocin and 22 virulence factor determinants. Additionally, E. coli phylogenetic groups were also determined. Pulsed-field gel electrophoresis (PFGE) was used for exclusion of clonal character of isolates. Results were compared to data from a previously published analysis of 1283 fecal commensal E. coli isolates. The frequency of bacteriocinogenic isolates (66.9%) was significantly higher in IBD E. coli compared to fecal commensal E. coli isolates (54.2%, p < 0.01). In the group of IBD E. coli isolates, a higher prevalence of determinants for group B colicins (i.e., colicins B, D, Ia, Ib, M, and 5/10) (p < 0.01), including a higher prevalence of the colicin B determinant (p < 0.01) was found. Virulence factor determinants encoding fimbriae (fimA, 91.0%; pap, 27.5%), cytotoxic necrotizing factor (cnf1, 11.2%), aerobactin synthesis (aer, 43.3%), and the locus associated with invasivity (ial, 9.0%) were more prevalent in IBD E. coli (p < 0.05 for all five determinants). E. coli isolates from IBD mucosal biopsies were more frequently bacteriocinogenic (84.6%, p < 0.01) compared to fecal IBD isolates and fecal commensal E. coli. PFGE analysis revealed clusters specific for IBD E. coli isolates (n = 11), for fecal isolates (n = 13), and clusters containing both IBD and fecal isolates (n = 10). ExPEC (Extraintestinal Pathogenic E. coli) virulence and colicin determinants appear to be important characteristics of IBD E. coli isolates, especially the E. coli isolates obtained directly from biopsy samples.
Collapse
|
5
|
Gao Q, Xia L, Liu J, Wang X, Gao S, Liu X. DNA microarray-mediated transcriptional profiling of avian pathogenic Escherichia coli O2 strain E058 during its infection of chicken. Microb Pathog 2016; 100:1-9. [PMID: 27569534 DOI: 10.1016/j.micpath.2016.08.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 08/24/2016] [Accepted: 08/24/2016] [Indexed: 01/15/2023]
Abstract
Avian pathogenic Escherichia coli (APEC) cause typical extraintestinal infections in poultry, including acute fatal septicemia, subacute pericarditis, and airsacculitis. These bacteria most often infect chickens, turkeys, ducks, and other avian species, and therefore pose a significant economic burden on the poultry industry worldwide. Few studies have analyzed the genome-wide transcriptional profile of APEC during infection in vivo. In this study, we examined the genome-wide transcriptional response of APEC O2 strain E058 in an in vivo chicken infection model to better understand the factors necessary for APEC colonization, growth, and survival in vivo. An Affymetrix multigenome DNA microarray, which contains most of the genomic open reading frames of E. coli K-12 strain MG1655, uropathogenic E. coli strain CFT073, and E. coli O157:H7 strain EDL 933, was used to profile the gene expression in APEC E058. We identified the in vivo transcriptional response of APEC E058 bacteria collected directly from the blood of infected chickens. Significant differences in expression levels were detected between the in vivo expression profile and the in vitro expression profile in LB medium. The genes highly expressed during infection were involved in metabolism, iron acquisition or transport, virulence, response to stress, and biological regulation. The reliability of the microarray data was confirmed by performing quantitative real-time PCR on 12 representative genes. Moreover, several significantly upregulated genes, including yjiY, sodA, phoB and spy, were selected to study their role in APEC pathogenesis. The data will help to better understand the mechanisms of APEC pathogenesis.
Collapse
Affiliation(s)
- Qingqing Gao
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| | - Le Xia
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| | - Juanhua Liu
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| | - Xiaobo Wang
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| | - Song Gao
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| |
Collapse
|
6
|
Gao Q, Ye Z, Wang X, Mu X, Gao S, Liu X. RstA is required for the virulence of an avian pathogenic Escherichia coli O2 strain E058. INFECTION GENETICS AND EVOLUTION 2014; 29:180-8. [PMID: 25461694 DOI: 10.1016/j.meegid.2014.11.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 11/21/2014] [Accepted: 11/22/2014] [Indexed: 11/25/2022]
Abstract
Certain strains of avian pathogenic Escherichia coli (APEC) cause severe extraintestinal infections in poultry, including acute fatal septicemia, subacute pericarditis, and airsacculitis. These bacteria contain an RstA/RstB regulatory system, a two-component system that may help APEC strains adapt to the extra-intestinal environment and survive under stressful conditions. Whether RstA correlates with APEC pathogenesis or acts as an APEC virulence factor has not been established. Here we provide the first evidence for an important role of rstA in APEC virulence. We generated an rstA-deficient mutant from the highly virulent APEC strain E058. Virulence of the mutant strain was evaluated in vivo and in vitro through bird infection assays, a cytotoxicity assay on chicken macrophage cell line HD-11, and a bactericidal assay to serum complement. Based on lethality assays in 1-day-old birds, rstA deletion from APEC E058 reduced the bacterial virulence in birds. The deletion also deeply impaired the capacity of APEC E058 to colonize deeper tissues of 5-week-old specific pathogen free chickens. No obvious gross or histopathological lesions were observed in the visceral organs of chickens challenged with the rstA-deficient strain. Also, rstA inactivation reduced the survival of APEC E058 within chicken macrophages. However, no significant differences were observed between the mutant and the wild-type strain in resistance to serum. Our data collectively show that the rstA gene functions in the pathogenesis of diseases caused by avian pathogenic E. coli.
Collapse
Affiliation(s)
- Qingqing Gao
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Zhengqin Ye
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Xiaobo Wang
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Xiaohui Mu
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Song Gao
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, Ministry of Agriculture, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| |
Collapse
|
7
|
Comparison and phylogenetic analysis of the ISS gene in two predominant avian pathogenic E. coli serogroups isolated from avian colibacillosis in Iran. Res Vet Sci 2012; 94:5-8. [PMID: 22854600 DOI: 10.1016/j.rvsc.2012.07.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 06/11/2012] [Accepted: 07/02/2012] [Indexed: 11/23/2022]
Abstract
The ISS (increased serum survival) gene and its protein product (ISS) of avian pathogenic Escherichia coli (APEC) are important characteristics of resistance to the complement system. The aims of this study were to clone, sequence and characterize sequence diversity of the ISS gene between two predominant serogroups in Iran and among those previously deposited in Genbank. The ISS gene of 309 bp from the APEC χ1390 strain was amplified by PCR, cloned and sequenced using pTZ57R/T vector. The ISS gene from the χ1390 strain has 100% identity among different serogroups of APEC in different geographical regions throughout the world. Phylogenetic analysis shows two different phylogenic groups among the different strains. Strong association of nucleotide sequences among different E. coli strains suggests that it may be a conserved gene and could be a suitable antigen to control and detect avian pathogenic E. coli, at least in our region. Currently, our group is working on the ISS protein as candidate vaccine in SPF poultry.
Collapse
|
8
|
Carotenoid supplementation and GnRH challenges influence female endocrine physiology, immune function, and egg-yolk characteristics in Japanese quail (Coturnix japonica). J Comp Physiol B 2012; 182:687-702. [DOI: 10.1007/s00360-011-0638-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 11/02/2011] [Accepted: 12/21/2011] [Indexed: 10/14/2022]
|
9
|
Abstract
Bacterial plasmids are self-replicating, extrachromosomal elements that are key agents of change in microbial populations. They promote the dissemination of a variety of traits, including virulence, enhanced fitness, resistance to antimicrobial agents, and metabolism of rare substances. Escherichia coli, perhaps the most studied of microorganisms, has been found to possess a variety of plasmid types. Included among these are plasmids associated with virulence. Several types of E. coli virulence plasmids exist, including those essential for the virulence of enterotoxigenic E. coli, enteroinvasive E. coli, enteropathogenic E. coli, enterohemorrhagic E. coli, enteroaggregative E. coli, and extraintestinal pathogenic E. coli. Despite their diversity, these plasmids belong to a few plasmid backbones that present themselves in a conserved and syntenic manner. Thanks to some recent research, including sequence analysis of several representative plasmid genomes and molecular pathogenesis studies, the evolution of these virulence plasmids and the implications of their acquisition by E. coli are now better understood and appreciated. Here, work involving each of the E. coli virulence plasmid types is summarized, with the available plasmid genomic sequences for several E. coli pathotypes being compared in an effort to understand the evolution of these plasmid types and define their core and accessory components.
Collapse
|
10
|
Sequence analysis and characterization of a transferable hybrid plasmid encoding multidrug resistance and enabling zoonotic potential for extraintestinal Escherichia coli. Infect Immun 2010; 78:1931-42. [PMID: 20160015 DOI: 10.1128/iai.01174-09] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
ColV plasmids of extraintestinal pathogenic Escherichia coli (ExPEC) encode a variety of fitness and virulence factors and have long been associated with septicemia and avian colibacillosis. These plasmids are found significantly more often in ExPEC, including ExPEC associated with human neonatal meningitis and avian colibacillosis, than in commensal E. coli. Here we describe pAPEC-O103-ColBM, a hybrid RepFIIA/FIB plasmid harboring components of the ColV pathogenicity island and a multidrug resistance (MDR)-encoding island. This plasmid is mobilizable and confers the ability to cause septicemia in chickens, the ability to cause bacteremia resulting in meningitis in the rat model of human disease, and the ability to resist the killing effects of multiple antimicrobial agents and human serum. The results of a sequence analysis of this and other ColV plasmids supported previous findings which indicated that these plasmid types arose from a RepFIIA/FIB plasmid backbone on multiple occasions. Comparisons of pAPEC-O103-ColBM with other sequenced ColV and ColBM plasmids indicated that there is a core repertoire of virulence genes that might contribute to the ability of some ExPEC strains to cause high-level bacteremia and meningitis in a rat model. Examination of a neonatal meningitis E. coli (NMEC) population revealed that approximately 58% of the isolates examined harbored ColV-type plasmids and that 26% of these plasmids had genetic contents similar to that of pAPEC-O103-ColBM. The linkage of the ability to confer MDR and the ability contribute to multiple forms of human and animal disease on a single plasmid presents further challenges for preventing and treating ExPEC infections.
Collapse
|
11
|
Johnson TJ, DebRoy C, Belton S, Williams ML, Lawrence M, Nolan LK, Thorsness JL. Pyrosequencing of the Vir plasmid of necrotoxigenic Escherichia coli. Vet Microbiol 2009; 144:100-9. [PMID: 20060660 DOI: 10.1016/j.vetmic.2009.12.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2009] [Revised: 12/11/2009] [Accepted: 12/16/2009] [Indexed: 10/20/2022]
Abstract
Necrotoxigenic Escherichia coli, or NTEC, are defined as E. coli producing the toxin known as cytotoxic necrotizing factor, or CNF. NTEC are responsible for various diseases of humans and animals, including urinary tract infection, septicemia, and diarrhea. A subgroup of NTEC known as NTEC-2 produce a variant of CNF (CNF-2) whose gene is located on a plasmid known as Vir. Because of its involvement in NTEC-2 pathogenesis and its broad distribution among production animals, a Vir plasmid from a bovine NTEC-2 strain was sequenced and analyzed. This plasmid was found to belong to the RepFIB and RepFIIA replicon types, and it totaled 138,682 base pairs in size. Within this plasmid was an approximately 60-kb pathogenicity island, defined by its possession of multiple virulence factors within distinct genetic regions of lower G+C content bounded by inverted repeats. Within this PAI were a variety of putative virulence factors, including F17b fimbrial genes, genes of a novel fimbrial operon, tibAC, hemolysins, and the cnf2 and cdt toxin-encoding genes. The occurrence of this plasmid's virulence- and replication-associated genes was sought among a collection of 96 CNF-2-positive isolates. The most prevalent genes among this collection included repA (RepFIB), cnf2, an ompP homolog, and the tib-AC genes encoding for aggregation and biofilm formation. The Vir plasmid has evolved from an IncFIB ancestral backbone, with the RepFIB locus apparently driving the acquisition of its accessory virulence-associated elements via site-specific recombination. Overall, the completed sequence of a Vir plasmid increases our understanding of NTEC-2 pathogenomics and IncFIB plasmid evolution.
Collapse
Affiliation(s)
- Timothy J Johnson
- Department of Veterinary and Biomedical Sciences, University of Minnesota, 1971 Commonwealth Ave, 205 Veterinary Science, Saint Paul, MN 55108, United States.
| | | | | | | | | | | | | |
Collapse
|
12
|
Derakhshandeh A, Zahraei Salehi T, Tadjbakhsh H, Karimi V. Identification, cloning and sequencing of Escherichia coli strain chi1378 (O78:K80) iss gene isolated from poultry colibacillosis in Iran. Lett Appl Microbiol 2009; 49:403-7. [PMID: 19622075 DOI: 10.1111/j.1472-765x.2009.02681.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To identify, clone and sequence the iss (increased serum survival) gene from E. coli strain chi1378 isolated from Iranian poultry and to predict its protein product, Iss. METHODS AND RESULTS The iss gene from E. coli strain chi1378 was amplified and cloned into the pTZ57R/T vector and sequenced. From the DNA sequence, the Iss predictive protein was evaluated using bioinformatics. Iss from strain chi1378 had 100% identity with other E. coli serotypes and isolates from different origins and also 98% identity with E. coli O157:H7 Iss protein. Phylogenetic analysis showed no significant different phylogenic groups among E. coli strains. CONCLUSIONS The strong association of predicted Iss protein among different E. coli strains suggests that it could be a good antigen to control and detect avian pathogenic E. coli (APEC). SIGNIFICANCE AND IMPACT OF THE STUDY Because the exact pathogenesis and the role of virulence factors are unknown, the Iss protein could be used as a target for vaccination in the future, but further research is required.
Collapse
Affiliation(s)
- A Derakhshandeh
- Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | | | | | | |
Collapse
|
13
|
Dziva F, Stevens MP. Colibacillosis in poultry: unravelling the molecular basis of virulence of avian pathogenicEscherichia coliin their natural hosts. Avian Pathol 2008; 37:355-66. [DOI: 10.1080/03079450802216652] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
14
|
Lynne AM, Skyberg JA, Logue CM, Doetkott C, Foley SL, Nolan LK. Characterization of a series of transconjugant mutants of an avian pathogenic Escherichia coli isolate for resistance to serum complement. Avian Dis 2007; 51:771-6. [PMID: 17992940 DOI: 10.1637/0005-2086(2007)51[771:coasot]2.0.co;2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Colibacillosis, caused by avian pathogenic Escherichia coli (APEC) is a major problem for the poultry industry resulting in significant losses annually. Previous work in our lab and by others has shown that the increased serum survival gene (iss) is a common trait associated with the virulence of APEC. This gene was first described for its contributions to E. coli serum resistance. However, recently published research has called the contribution of iss to this trait into question. In the present study, the level of serum resistance conferred on an E. coli isolate by iss is examined. Additionally, the contribution of lambda bor gene to E. coli serum resistance is studied, as iss is thought to be derived from bor and bor occurs commonly among E. coli. To better understand the iss and bor contributions to serum resistance, a series of iss and bor mutants was generated. An iss deletion (iss-) mutant showed a significant drop in its resistance to serum. Similarly, a bor mutant showed a drop in serum resistance but not as drastic as that observed with the iss mutant, suggesting that iss contributes more to serum resistance than bor in this E. coli strain. Also, when iss was reintroduced into the iss- mutant the wild-type level of serum resistance was restored, confirming that the deletion of iss was responsible for the change in resistance seen in the mutant.
Collapse
Affiliation(s)
- Aaron M Lynne
- National Farm Medicine Center, Marshfield Clinic Research Foundation, Marshfield, WI 54449, USA
| | | | | | | | | | | |
Collapse
|
15
|
Lynne AM, Skyberg JA, Logue CM, Nolan LK. Detection of Iss and Bor on the surface of Escherichia coli. J Appl Microbiol 2007; 102:660-6. [PMID: 17309614 DOI: 10.1111/j.1365-2672.2006.03133.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To confirm the presence of Iss and Bor on the outer membrane of Escherichia coli using Western blots of outer membrane protein (OMP) preparations and fluorescence microscopy, and explore the use of fluorescence microscopy for the detection of avian pathogenic E. coli (APEC) and diagnosis of avian colibacillosis. METHODS AND RESULTS Knockout mutants of iss and bor were created using a one-step recombination of target genes with PCR-generated antibiotic resistance cassettes. Anti-Iss monoclonal antibodies (Mabs) that cross-react with Bor protein were used to study the mutants relative to the wild-type organism. These Mabs were used as reagents to study OMP preparations of the mutants with Western blotting and intact E. coli cells with fluorescence microscopy. Iss and Bor were detected in Western blots of OMP preparations of the wild type. Also, Iss was detected on Deltabor mutants, and Bor was detected on Deltaiss mutants. Iss and Bor were also detected on the surface of the intact, wild-type cells and mutants using fluorescence microscopy. CONCLUSIONS These results demonstrate that Bor and Iss are exposed on E. coli's outer membrane where they may be recognized by the host's immune system. SIGNIFICANCE AND IMPACT OF THE STUDY To our knowledge, this is the first report confirming Iss' location in the outer membrane of an E. coli isolate. Such surface exposure has implications for the use of these Mabs for APEC detection and colibacillosis control.
Collapse
Affiliation(s)
- A M Lynne
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | | | | | | |
Collapse
|
16
|
Johnson TJ, Johnson SJ, Nolan LK. Complete DNA sequence of a ColBM plasmid from avian pathogenic Escherichia coli suggests that it evolved from closely related ColV virulence plasmids. J Bacteriol 2006; 188:5975-83. [PMID: 16885466 PMCID: PMC1540072 DOI: 10.1128/jb.00204-06] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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.
Collapse
Affiliation(s)
- Timothy J Johnson
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 1802 Elwood Drive, VMRI 2, Iowa State University, Ames, IA 50011, USA
| | | | | |
Collapse
|
17
|
Johnson TJ, Siek KE, Johnson SJ, Nolan LK. DNA sequence of a ColV plasmid and prevalence of selected plasmid-encoded virulence genes among avian Escherichia coli strains. J Bacteriol 2006; 188:745-58. [PMID: 16385064 PMCID: PMC1347294 DOI: 10.1128/jb.188.2.745-758.2006] [Citation(s) in RCA: 228] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ColV plasmids have long been associated with the virulence of Escherichia coli, despite the fact that their namesake trait, ColV production, does not appear to contribute to virulence. Such plasmids or their associated sequences appear to be quite common among avian pathogenic E. coli (APEC) and are strongly linked to the virulence of these organisms. In the present study, a 180-kb ColV plasmid was sequenced and analyzed. This plasmid, pAPEC-O2-ColV, possesses a 93-kb region containing several putative virulence traits, including iss, tsh, and four putative iron acquisition and transport systems. The iron acquisition and transport systems include those encoding aerobactin and salmochelin, the sit ABC iron transport system, and a putative iron transport system novel to APEC, eit. In order to determine the prevalence of the virulence-associated genes within this region among avian E. coli strains, 595 APEC and 199 avian commensal E. coli isolates were examined for genes of this region using PCR. Results indicate that genes contained within a portion of this putative virulence region are highly conserved among APEC and that the genes of this region occur significantly more often in APEC than in avian commensal E. coli. The region of pAPEC-O2-ColV containing genes that are highly prevalent among APEC appears to be a distinguishing trait of APEC strains.
Collapse
Affiliation(s)
- Timothy J Johnson
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 1802 Elwood Drive, VMRI #2, Iowa State University, Ames, IA 50011.
| | | | | | | |
Collapse
|
18
|
Roland K, Karaca K, Sizemore D. Expression of Escherichia coli antigens in Salmonella typhimurium as a vaccine to prevent airsacculitis in chickens. Avian Dis 2005; 48:595-605. [PMID: 15529982 DOI: 10.1637/7178-031004r1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Avian pathogenic Escherichia coli strains are associated with a variety of extraintestinal poultry diseases, including airsacculitis, colisepticemia, and cellulitis. A number of E. coli serotypes are associated with these diseases, although the most prevalent serotype is O78. Fimbrial proteins expressed by these strains appear to be important virulence factors, including type 1 fimbriae, P fimbriae, and curli. We have been working to develop an effective vaccine to protect chickens against these diseases. We have previously shown that an attenuated Salmonella typhimurium strain expressing O78 lipopolysaccharide provides protection against challenge with an O78 avian pathogenic E. coli strain. In this work, we have constructed an attenuated S. typhimurium that expresses both the O78 lipopolysaccharide and E. coli-derived type 1 fimbriae. In these studies, chickens were vaccinated at day of hatch and again at 2 wk of age. Birds were challenged at 4 wk of age. We found that the vaccine candidate provided significant protection against airsacculitis as compared to untreated controls or birds vaccinated with an attenuated S. typhimurium that did not express any E. coli antigens. In a separate experiment, challenged vaccinates showed significant weight gain compared to challenged nonvaccinates. We were not able to demonstrate protection against E. coli O1 or O2 serotype challenge, nor against challenge with wild-type S. typhimurium.
Collapse
Affiliation(s)
- Kenneth Roland
- AVANT Immunotherapeutics, Inc., 8620 Pennell Drive, Overland, MO 63114, USA
| | | | | |
Collapse
|
19
|
Gibbs PS, Wooley RE. Comparison of the Intravenous Chicken Challenge Method with the Embryo Lethality Assay for Studies in Avian Colibacillosis. Avian Dis 2003; 47:672-80. [PMID: 14562896 DOI: 10.1637/7011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In previous studies, the embryo lethality assay (ELA) was able to discriminate between virulent and avirulent avian Escherichia coli isolates and to predict percent mortality of the embryos resulting from an isolate based on three traits. The abilities to resist host complement, presence of Colicin V activity, and presence of the increased serum survival gene cluster (iss), were used together in a logistic regression analysis to predict the percentage of embryo deaths resulting from each of 20 avian E. coli isolates used in the ELA. In the present study, the same 20 isolates are used in an intravenous chicken challenge model in an effort to determine whether the ELA could be used to replace chicken challenge studies. Correlations between the mortality and a combination of mortality and morbidity (the survivors at trial termination with lesions suggestive of colibacillosis) and the previous ELA results and with selected isolate traits were performed. Additionally, resulting body weights in surviving chickens were compared between groups. The highest positive correlations were observed between the ELA and the combined mortality/morbidity of the intravenous challenge (r = 0.861, P < 0.0001 for the first ELA challenge, and r = 0.830, P < 0.0001 for the second ELA challenge). The IV challenge combined mortality/morbidity results had the highest correlation coefficients with the presence of iss (r = 0.864, P < 0.0001) and the expression of ColV (r = 0.878, P < 0.0001). The presence of tsh was slightly correlated with mortality (r = 0.465, P = .0389) but demonstrated a higher correlation with the combined mortality and morbidity of the IV challenge (r = 0.558, P = 0.0106). Even though the ELA results in a higher number of nonspecific deaths, the two challenge methods exhibit similar results and a high correlation with each other. Interestingly, some of the isolates showed differences in their ability to cause mortality between the ELA and the IV challenge model. Furthermore, some isolates reflected significant differences in body weights of surviving birds at IV trial termination.
Collapse
Affiliation(s)
- Penelope S Gibbs
- Department of Veterinary and Microbiological Sciences, College of Agriculture, Food Systems, and Natural Resources, North Dakota State University, Fargo, ND 58105, USA
| | | |
Collapse
|
20
|
Gibbs PS, Maurer JJ, Nolan LK, Wooley RE. Prediction of chicken embryo lethality with the avian Escherichia coli traits complement resistance, colicin V production, and presence of the increased serum survival gene cluster (iss). Avian Dis 2003; 47:370-9. [PMID: 12887196 DOI: 10.1637/0005-2086(2003)047[0370:pocelw]2.0.co;2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Differentiating between virulent and avirulent avian Escherichia coli isolates continues to be a problem for poultry diagnostic laboratories and the study of colibacillosis in poultry. The ability of a laboratory to conduct one simple test that correlates with virulence would simplify studies in these areas; however, previous studies have not enabled researchers to establish such a test. In this study, the occurrence of certain phenotypic and genotypic traits purported to contribute to avian E. coli virulence in 20 avian E. coli isolates was correlated with the results of embryo challenge studies. This analysis was undertaken in an effort to determine which trait(s) best identified each avian E. coli isolate as virulent or avirulent. Traits selected were complement resistance, production of colicin V (ColV), motility, type F1 pili expression, presence of the temperature-sensitive hemagglutinin gene (tsh), and presence of the increased serum survival genetic locus (iss). ColV production, complement resistance, and presence of the iss genetic element were the three traits most highly correlated with high embryo lethality. A logistic regression model was used to predict the embryo lethality results on the basis of the most frequent isolate characteristics. Results indicate that ColV, complement resistance, and if are significant predictor variables for the percentage of embryo lethality resulting from challenge with a specific avian E. coli isolate. However, no single trait has the ability to predict virulent isolates 100% of the time. Such results suggest the possibility that the embryo lethality assay may prove to be the one test needed to determine if an avian E. coli isolate is virulent.
Collapse
Affiliation(s)
- Penelope S Gibbs
- Department of Veterinary and Microbiological Sciences, College of Agriculture, North Dakota State University, Fargo, ND 58105, USA
| | | | | | | |
Collapse
|
21
|
da Silveira WD, Lancellotti M, Ferreira A, Solferini VN, de Castro AFP, Stehling EG, Brocchi M. Determination of the clonal structure of avian Escherichia coli strains by isoenzyme and ribotyping analysis. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2003; 50:63-9. [PMID: 12675896 DOI: 10.1046/j.1439-0450.2003.00607.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Forty-nine avian Escherichia coli strains isolated from different outbreak cases of septicemia (24), swollen head syndrome (14) and omphalitis (11), and 20 strains isolated from poultry with no signs of the mentioned illnesses, for a total of 69 strains, were typed by isoenzyme profile and ribotyping analysis by restriction fragment length polymorphism (RFLP). Isoenzyme analysis discriminated better among strains (0-0.07 degree of genetic dissimilarity) than ribotyping analysis (0- 0.02 degree of genetic dissimilarity). The enzyme profiles of the E. coli isolates allowed the identification of 33 clones that were organized into six main clusters (A-F). Cluster A comprised 87% of the pathogenic strains and had no commensal strains, while commensal strains were assigned to clusters B-F. The ribotyping analysis resulted in a more heterogenous distribution of strains but most of those that cause the same type of infection were kept close together. Taken as a whole, these results demonstrate that pathogenic clones are more similar to one another when compared with commensal strains and suggest a correlation between the genetic background and the pathogenic characteristics of avian pathogenic E. coli strains.
Collapse
Affiliation(s)
- W D da Silveira
- Department of Microbiology and Immunology, Biology Institute, CP 6109, Campinas State University, SP, Brazil.
| | | | | | | | | | | | | |
Collapse
|
22
|
Jeffrey JS, Nolan LK, Tonooka KH, Wolfe S, Giddings CW, Horne SM, Foley SL, Lynne AM, Ebert JO, Elijah LM, Bjorklund G, Pfaff-McDonough SJ, Singer RS, Doetkott C. Virulence factors of Escherichia cofi from cellulitis or colisepticemia lesions in chickens. Avian Dis 2002; 46:48-52. [PMID: 11922349 DOI: 10.1637/0005-2086(2002)046[0048:vfoecf]2.0.co;2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This study was designed to compare virulence factors of cellulitis-derived Escherichia coli to colisepticemic E. coli in order to clarify whether E. coli associated with cellulitis comprise a unique subset of pathogenic E. coli. Isolates were tested for serotype, capsule, aerobactin production, colicin production, the presence of the iss gene, and serum resistance. Untypable isolates made up the greatest percentage of each group. Serotypes O2 and O78 were the most commonly identified among both groups of isolates. No statistical differences in the distribution of aerobactin or colicin production, capsule, or iss gene were observed between groups. Cluster analysis showed that 90% of the E. coli isolates had greater than 42% livability in serum-resistance tests. No separation of colisepticemic vs. cellulitis E. coli isolates was observed on the basis of SR. Colicin production by E. coli was highly correlated with serum resistance (P = 0.0029). These data suggest that cellulitis E. coli have virulence traits similar to those of colisepticemic E. coli.
Collapse
Affiliation(s)
- J S Jeffrey
- Department of Population, Health and Reproduction, School of Veterinary Medicine, Veterinary Medicine Teaching and Research Center, Tulare, CA 93274, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Wooley RE, Ritchie BW, Currin MF, Chitwood SW, Sanchez S, Crane MM, Lamberski N. In vitro inhibition of Salmonella organisms isolated from reptiles by an inactivated culture of microcin-producing Escherichia coli. Am J Vet Res 2001; 62:1399-401. [PMID: 11560267 DOI: 10.2460/ajvr.2001.62.1399] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine whether an inactivated culture of a microcin-producing avian Escherichia coli was capable of killing Salmonella isolates from reptiles in an in vitro test system. SAMPLE POPULATION 57 Salmonella isolate from reptiles. PROCEDURE A wild-type avian E. coli electrotransformed with a plasmid coding for the production of microcin 24 was tested in an in vitro microassay system for its ability to kill 57 Salmonella spp isolated from reptiles. The reptile population included snakes, iguana, frilled lizards, turtles, other lizards, and unspecified reptiles. RESULTS 44 of the Salmonella isolates were inhibited strongly, compared with the in vitro assay controls; 12 had weak inhibition, and 1 was not inhibited by the microcin-producing E. coli. Thirteen of the 57 isolates had resistance to at least 1 antibiotic, primarily streptomycin. There were 9 O serogroups identified in the 57 isolates, with serogroup H being the most prevalent (18 to 57). CONCLUSION AND CLINICAL RELEVANCE Antibiotics are not recommended to eliminate Salmonella organisms from reptiles because of the development of antibiotic resistance. Further studies are necessary to determine whether the use of microcin-producing bacteria will be effective in controlling Salmonella infections in companion reptiles.
Collapse
Affiliation(s)
- R E Wooley
- Department of Medical Microbiology and Parasitology, College of Veterinary Medicine, University of Georgia, Athens 30602, USA
| | | | | | | | | | | | | |
Collapse
|
24
|
Dozois CM, Dho-Moulin M, Brée A, Fairbrother JM, Desautels C, Curtiss R. Relationship between the Tsh autotransporter and pathogenicity of avian Escherichia coli and localization and analysis of the Tsh genetic region. Infect Immun 2000; 68:4145-54. [PMID: 10858231 PMCID: PMC101714 DOI: 10.1128/iai.68.7.4145-4154.2000] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The temperature-sensitive hemagglutinin Tsh is a member of the autotransporter group of proteins and was first identified in avian-pathogenic Escherichia coli (APEC) strain chi7122. The prevalence of tsh was investigated in 300 E. coli isolates of avian origin and characterized for virulence in a 1-day-old chick lethality test. Results indicate that among the tsh-positive APEC isolates, 90.6% belonged to the highest virulence class. Experimental inoculation of chickens with chi7122 and an isogenic tsh mutant demonstrated that Tsh may contribute to the development of lesions within the air sacs of birds but is not required for subsequent generalized infection manifesting as perihepatitis, pericarditis, and septicemia. Conjugation and hybridization experiments revealed that the tsh gene is located on a ColV-type plasmid in many of the APEC strains studied, including strain chi7122, near the colicin V genes in most of these strains. DNA sequences flanking the tsh gene of strain chi7122 include complete and partial insertion sequences and phage-related DNA sequences, some of which were also found on virulence plasmids and pathogenicity islands present in various E. coli pathotypes and other pathogenic members of the Enterobacteriaceae. These results demonstrate that the tsh gene is frequently located on the ColV virulence plasmid in APEC and suggest a possible role of Tsh in the pathogenicity of E. coli for chickens in the early stages of infection.
Collapse
Affiliation(s)
- C M Dozois
- Department of Biology, Washington University, St. Louis, Missouri 63130, USA
| | | | | | | | | | | |
Collapse
|
25
|
Ginns CA, Benham ML, Adams LM, Whithear KG, Bettelheim KA, Crabb BS, Browning GF. Colonization of the respiratory tract by a virulent strain of avian Escherichia coli requires carriage of a conjugative plasmid. Infect Immun 2000; 68:1535-41. [PMID: 10678971 PMCID: PMC97312 DOI: 10.1128/iai.68.3.1535-1541.2000] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The E3 strain of E. coli was isolated in an outbreak of respiratory disease in broiler chickens, and experimental aerosol exposure of chickens to this strain induced disease similar to that seen in the field. In order to establish whether the virulent phenotype of this strain was associated with carriage of particular plasmids, four plasmid-cured derivatives, each lacking two or more of the plasmids carried by the wild-type strain, were assessed for virulence. Virulence was found to be associated with one large plasmid, pVM01. Plasmid pVM01 was marked by introduction of the transposon TnphoA, carrying kanamycin resistance, and was then cloned by transformation of E. coli strain DH5alpha. The cloned plasmid was then reintroduced by conjugation into an avirulent plasmid-cured derivative of strain E3 which lacked pVM01. The conjugant was shown to be as virulent as the wild-type strain E3, establishing that this plasmid is required for virulence following aerosol exposure. This virulence plasmid conferred expression of a hydroxamate siderophore, but not colicins, on both strain E3 and strain DH5alpha. Carriage of this plasmid was required for strain E3 to colonize the respiratory tracts of chickens but was not necessary for colonization of the gastrointestinal tract. However, the virulence plasmid did not confer virulence, or the capacity to colonize the respiratory tract, on strain DH5alpha. Thus, these studies have established that infection of chickens with E. coli strain E3 by the respiratory route is dependent on carriage of a conjugative virulence plasmid, which confers the capacity to colonize specifically the respiratory tract and which also carries genes for expression of a hydroxymate siderophore. These findings will facilitate identification of the specific genes required for virulence in these pathogens.
Collapse
Affiliation(s)
- C A Ginns
- Department of Veterinary Science, The University of Melbourne, Parkville, Victoria 3052, Australia
| | | | | | | | | | | | | |
Collapse
|
26
|
Bass L, Liebert CA, Lee MD, Summers AO, White DG, Thayer SG, Maurer JJ. Incidence and characterization of integrons, genetic elements mediating multiple-drug resistance, in avian Escherichia coli. Antimicrob Agents Chemother 1999; 43:2925-9. [PMID: 10582884 PMCID: PMC89589 DOI: 10.1128/aac.43.12.2925] [Citation(s) in RCA: 200] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Antibiotic resistance among avian bacterial isolates is common and is of great concern to the poultry industry. Approximately 36% (n = 100) of avian, pathogenic Escherichia coli isolates obtained from diseased poultry exhibited multiple-antibiotic resistance to tetracycline, oxytetracycline, streptomycin, sulfonamides, and gentamicin. Clinical avian E. coli isolates were further screened for the presence of markers for class 1 integrons, the integron recombinase intI1 and the quaternary ammonium resistance gene qacEDelta1, in order to determine the contribution of integrons to the observed multiple-antibiotic resistance phenotypes. Sixty-three percent of the clinical isolates were positive for the class 1 integron markers intI1 and qacEDelta1. PCR analysis with the conserved class 1 integron primers yielded amplicons of approximately 1 kb from E. coli isolates positive for intI1 and qacEDelta1. These PCR amplicons contained the spectinomycin-streptomycin resistance gene aadA1. Further characterization of the identified integrons revealed that many were part of the transposon Tn21, a genetic element that encodes both antibiotic resistance and heavy-metal resistance to mercuric compounds. Fifty percent of the clinical isolates positive for the integron marker gene intI1 as well as for the qacEDelta1 and aadA1 cassettes also contained the mercury reductase gene merA. The correlation between the presence of the merA gene with that of the integrase and antibiotic resistance genes suggests that these integrons are located in Tn21. The presence of these elements among avian E. coli isolates of diverse genetic makeup as well as in Salmonella suggests the mobility of Tn21 among pathogens in humans as well as poultry.
Collapse
Affiliation(s)
- L Bass
- Departments of Microbiology, University of Georgia, Athens, Georgia 30602, USA
| | | | | | | | | | | | | |
Collapse
|
27
|
Edens FW, Qureshi RA, Parkhurst CR, Qureshi MA, Havenstein GB, Casas IA. Characterization of two Escherichia coli isolates associated with poult enteritis and mortality syndrome. Poult Sci 1997; 76:1665-73. [PMID: 9438280 DOI: 10.1093/ps/76.12.1665] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Two colonial types (1 and 2) of Escherichia coli are represented predominantly in cultures isolated from turkey poults with poult enteritis and mortality syndrome (PEMS). Biotype codes determined using two systems (BBL: 36570 and 34560 for colony types 1 and 2, respectively; API-20E: 5144572 and 5144512 for colony types 1 and 2, respectively) clearly establish these organisms as E. coli. These isolates were not clearly divergent from the general profile for E. coli, but colony type 2 differs from colony type 1 with regard to its negative reactions for ornithine decarboxylase and the fermentation of dulcitol, rhamnose, sucrose, and melibiose, suggesting that it is atypical. Colony type 1 is nonserotypable and nonmotile, whereas colony type 2 is serotyped as O136: motile because it has H antigens associated with flagella. Capsular antigens were not found, but thin capsules were seen on cells from both colony types in stained preparations. Cultural morphology was different with colony type 1 having a circular, mucoid, raised morphology and colony type 2 having an irregular, flat, rough morphology. Colony type 1 has a doubling time at 37 C of about 20 min, whereas colony type 2 doubles in 30 min. Furthermore, colony type 1 is a potent colicin producer, but colony type 2 is not a colicin producer. Both E. coli isolates have resistance profiles for multiple antibiotics. Each strain responds to third generation fluoroquinolone antibiotics by changing their biotypes and become resistant after culturing once in their presence. These E. coli are proposed as possible etiological links in the complex series of events that take place in poults susceptible to PEMS.
Collapse
Affiliation(s)
- F W Edens
- Department of Poultry Science, North Carolina State University, Raleigh 27695-7635, USA
| | | | | | | | | | | |
Collapse
|