scholarly journals PSVI-10 Detection of E. coli virulence genes during the pre-weaning and peri-weaning period in young meat goats

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 201-202
Author(s):  
Eunice Ndegwa ◽  
Aber Alahmde

Abstract It has been postulated that changes in prevalence of E. coli isolates with particular virulence genes in animals may be affected by many factors including age, feed, geographical location and stress. The weaning period represents stressful stage during the growth of farm animals. To evaluate if weaning stress affects the prevalence of E. coli possessing virulence genes; shiga toxin (Stx), hemolysin (hly) and intimin (eae) in young meat goats, fecal samples were collected during pre-weaning period, day of weaning (0DPW), one day after weaning (1DPW), two days after weaning (2DPW) and 7 days after weaning (7DPW). Two hundred forty seven two E. coli isolates were screened for the virulence genes. All four virulence genes (Stx1, Stx2, Hly, and eae) evaluated were detected in E. coli during the peri-weaning period while only stx1, eae and hly were detected during the pre-weaning period. No Stx2 had been detected during the pre-weaning period. Both Stx1 and Hly frequency of detection increased significantly from 0DPW to 2DPW and then decreased on 7DPW. The Stx2 gene remained relatively the same between 0DPW and 7DPW. The frequency of eae detection was highest during the pre-weaning period but also increased significantly from 0DPW to 7DPW. Further characterization of peri-weaning isolates possessing either Stx2 or eae revealed that some belonged to serotypes important to animal and public health including O26, O103 and O146. We highlight a previously unreported finding on pattern of colonization by E. coli in young meat goats before and during peri-weaning period. This trend may be suggestive that strains of E. coli harboring specific virulence genes proliferate during times of stress such as weaning in young meat goats while others predominantly colonize very young animals. The significance of E. coli isolates possessing the various virulence genes in relation to animal health need further evaluation.

Author(s):  
J. N. Silva ◽  
M. D. Baliza ◽  
F. Freitas ◽  
E. S Cruz ◽  
V. M. A. Camilo ◽  
...  

Abstract Many Solidarity Economic Venture (SEV) are family farmers who seek to add value to production through artisanal processing, which can lead to food contamination. Thus, this study aimed to genotypically characterize thermotolerant coliforms (TtC) strains from food produced by local agribusinesses of SEV during January to April 2019. Samples from thirteen production units (PU) from the SEV were submitted to a microbiological analysis of thermotolerant coliforms (AFNOR 3M1/2 – 09/89), using a fast count method in Petrifilm™ dishes. The Polymerase Chain Reaction (PCR) technique was used to verify the following virulence genes (VGs) associated with Escherichia coli: stx, typical from enterohemorrhagic E. coli (EHEC); bfpA typical from entheropathogenic E. coli (EPEC) and elt and slt, typical from entherotoxigenic E. coli (ETEC). The results showed that two samples of queijadinha (typical Brazilian candy made with eggs and coconut) and one sample of cassava cake presented characteristic colonies TtC. This way, three strains were isolated in order to perform the PCR technique. However, the genes used in the reaction were not detected in the isolated strains. Therefore, it is suggested that the isolated strains are from E. coli pathotypes with different virulence genes than the ones analyzed belong other types of TtC, such as Enterobacter and Klebsiella. Although the virulence of genes has not been confirmed, the presence of TtC on food indicates hygiene flaws during production and, therefore, measurements to control and prevent contamination should be taken.


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 ◽  
...  

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.


2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Bilel Hassen ◽  
Ahlem Jouini ◽  
Monia Elbour ◽  
Safa Hamrouni ◽  
Abderrazek Maaroufi

Extended-spectrum β-lactamase and their molecular mechanism in Enterobacteriaceae were analyzed in 126 fish samples of 9 various wild species, living in the lagoon of Bizerte in Tunisia. Fifty-nine (59) Gram-negative strains were isolated and identified as Escherichia coli (n=24), Klebsiella pneumonia (n=21), Citrobacter freundii (n=8), and Shigella boydii (n=6). Forty-seven ESBL producers were identified using the synergic test. β-Lactamase genes detected were blaCTX-M-1 (E. coli/15; K. pneumonia/8; C. freundii/1; Sh. boydii/1), blaCTX-M-1+ blaOXA-1 (E. coli/4; K. pneumonia/3), blaCTX-M-1+ blaTEM-1-a (K. pneumonia/2), blaCTX-M-15+ blaTEM-1-a (K. pneumonia/1; Sh. boydii/1), blaCTX-M-15+ blaOXA-1 (K. pneumonia/1), blaCTX-M-15 (E. coli/3; K. pneumonia/1; Sh. boydii/3), and blaCTX-M-9 (C. freundii/3). Most strains (84.7%) showed a multiresistant phenotype. qnrA and qnrB genes were identified in six E. coli and in ten E. coli+one K. pneumonia isolates, respectively. The resistance to tetracycline and sulfonamide was conferred by the tet and sul genes. Characterization of phylogenic groups in E. coli isolates revealed phylogroups D (n=20 strains), B2 (n=2), and A (n=2). The studied virulence factor showed prevalence of fimA genes in 9 E. coli isolates (37.5%). Similarly, no strain revealed the three other virulence factors tested (eae, aer, and cnf1). Our findings confirmed that the lagoons of Bizerte may be a reservoir of multidrug resistance/ESBL-producing Enterobacteriaceae. This could lead to indisputable impacts on human and animal health, through the food chain.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Solomon Abreham ◽  
Akafete Teklu ◽  
Eric Cox ◽  
Tesfaye Sisay Tessema

Abstract Background Cattle have been identified as a major reservoir of E. coli O157:H7 for human infection; the ecology of the organism in sheep and goats is less understood. This study was carried out to determine prevalence, source of infection, antibiotic resistance and molecular characterization of Escherichia coli O157: H7 isolated from sheep and goat. Methods Systematic random sampling was carried out at Modjo export abattoir, Ethiopia, from November 2012 to April 2013 to collect 408 samples from 72 sheep and 32 goats. Samples collected were skin swabs, fecal samples, intestinal mucosal swabs and the inside and outside part of carcasses as well as carcass in contacts such as workers hands, knife, hook and carcass washing water. Then, samples were processed following standard bacteriological procedures. Non-Sorbitol fermenting colonies were tested on latex agglutination test and the positives are subjected to PCR for detection of attaching and effacing genes (eaeA) and shiga toxin producing genes (stx1 and stx2). All E. coli O157:H7 isolates were checked for their susceptibility pattern towards 15 selected antibiotics. Results E. coli O157:H7 were detected in only 20/408 samples (4.9%). Among these 20 positive samples, 70% (14/20), 25% (5/20) and 5% (1/20) were from sheep, goats and knife samples, respectively. No significant associations were found between carcasses and the assumed sources of contaminations. Of all the 20 isolates virulence genes were found in 10 (50%) of them; 3 (15%) with only the eaeA gene and 7(35%) expressing eaeA and stx2 genes. All the isolates were susceptible to Norfloxacin (NOR) (100%). Conclusions The presence of virulence genes shows E. coli O157:H7 is a potential source of human infection in Ethiopia.


2000 ◽  
Vol 68 (10) ◽  
pp. 5933-5942 ◽  
Author(s):  
Lyla J. Melkerson-Watson ◽  
Christopher K. Rode ◽  
Lixin Zhang ◽  
Betsy Foxman ◽  
Craig A. Bloch

ABSTRACT Escherichia coli J96 is a uropathogen having both broad similarities to and striking differences from nonpathogenic, laboratoryE. coli K-12. Strain J96 contains three large (>100-kb) unique genomic segments integrated on the chromosome; two are recognized as pathogenicity islands containing urovirulence genes. Additionally, the strain possesses a fourth smaller accessory segment of 28 kb and two deletions relative to strain K-12. We report an integrated physical and genetic map of the 5,120-kb J96 genome. The chromosome contains 26 NotI, 13 BlnI, and 7 I-CeuI macrorestriction sites. Macrorestriction mapping was rapidly accomplished by a novel transposon-based procedure: analysis of modified minitransposon insertions served to align the overlapping macrorestriction fragments generated by three different enzymes (each sharing a common cleavage site within the insert), thus integrating the three different digestion patterns and ordering the fragments. The resulting map, generated from a total of 54 mini-Tn10insertions, was supplemented with auxanography and Southern analysis to indicate the positions of insertionally disrupted aminosynthetic genes and cloned virulence genes, respectively. Thus, it contains not only physical, macrorestriction landmarks but also the loci for eight housekeeping genes shared with strain K-12 and eight acknowledged urovirulence genes; the latter confirmed clustering of virulence genes at the large unique accessory chromosomal segments. The 115-kb J96 plasmid was resolved by pulsed-field gel electrophoresis inNotI digests. However, because the plasmid lacks restriction sites for the enzymes BlnI and I-CeuI, it was visualized in BlnI and I-CeuI digests only of derivatives carrying plasmid inserts artificially introducing these sites. Owing to an I-SceI site on the transposon, the plasmid could also be visualized and sized from plasmid insertion mutants after digestion with this enzyme. The insertional strains generated in construction of the integrated genomic map provide useful physical and genetic markers for further characterization of the J96 genome.


2011 ◽  
Vol 78 (5) ◽  
pp. 1615-1618 ◽  
Author(s):  
Lydia V. Rump ◽  
Sonya Bodeis-Jones ◽  
Jason Abbott ◽  
Shaohua Zhao ◽  
Julie Kase ◽  
...  

ABSTRACTEscherichia coliO104 isolates collected from different sources in the United States were examined for virulence genes typical of enterohemorrhagicE. coliand those identified in the O104:H4 isolate associated with the 2011 German outbreak. The unexpected presence of virulence markers in these isolates highlights the importance of screening unusual and potentially pathogenic Shiga toxin-producingE. coliserotypes.


2018 ◽  
Vol 120 (7) ◽  
pp. 1457-1473 ◽  
Author(s):  
Edwin Barrios-Villa ◽  
Gerardo Cortés-Cortés ◽  
Patricia Lozano Zarain ◽  
Sergio Romero-Romero ◽  
Norarizbeth Lara Flores ◽  
...  

Purpose Broad-spectrum cephalosporin resistance is rapidly increasing in Escherichia coli, representing a food safety problem. The purpose of this paper is to characterize eight extended-spectrum-ß-lactamase (ESBL) and acquired AmpC ß-lactamase-producing E. coli isolates and virotypes associated, obtained from chicken and pork food samples in Puebla, Mexico. Design/methodology/approach Samples (36 from chicken and 10 from pork) were cultured on Levine agar plates supplemented with cefotaxime (2 mg/L) for isolation of cefotaxime-resistant (CTXR) E. coli. CTXR-E. coli isolates were detected in 33 of 46 samples (72 percent), and one isolate/sample was characterized (28 from chicken and 5 from pork), for ESBL production, phylogenetic group, sequence typing, resistance and virulence genes by PCR and sequencing. Findings Results showed 16 ESBL-E. coli (35 percent) (12/16 belonging to phylogroup B1) and 8 CMY-2-E. coli (17 percent). ESBL detected were as follows (number of isolates): CTX-M-2 (8); CTX-M-1 (2); CTX-M-15 (1); SHV-2a (4) and TEM-52c (1). In total, 20 different sequence types (STs) were identified among the ESBL- or CMY-2-producing E. coli strains, which included four new ones. The CTX-M-15 β-lactamase was detected in one E. coli ST617-ST10 Cplx-B1 strain that also carried ibeA gene. One CMY-2-positive strain of lineage ST224-B2 was detected and it carried the qnrA1 gene. Originality/value In this study, a ST131-based virotyping scheme for strains from food of animal origin was established since this kind of strains constitutes an important vehicle of virulent ESBL- and CMY-2-producing E. coli isolates, which could be transmitted to humans by direct contact or through the food chain.


2021 ◽  
Vol 4 ◽  
pp. 18
Author(s):  
Kwabena Obeng Duedu ◽  
Joana Qwansima Mends ◽  
Reuben Ayivor-Djanie ◽  
Priscilla Efua Essandoh ◽  
Emmanuel Mawuli Nattah ◽  
...  

Background: Phenotypic characterization of antimicrobial resistance (AMR) in bacteria has remained the gold standard for investigation and monitoring of what resistance is present in an organism. However, the process is laborious and not attractive for screening multiple plasmids from a microbial community (plasmidomes). Instead, genomic tools are used, but a major bottle neck that presence of genes does not always translate into phenotypes. Methods: We designed the plasmidome AMR screening (PAMRS) workflow to investigate the presence of antibiotic resistant phenotypes in a plasmidome using Escherichia coli as a host organism. Plasmidomes were extracted from the faecal matter of chicken, cattle and humans using commercial plasmid extraction kits. Competent E. coli cells were transformed and evaluated using disk diffusion. Thirteen antibiotic resistant phenotypes were screened. Results: Here, we show that multiple antibiotic resistant phenotypes encoded by plasmids can be rapidly screened simultaneously using the PAMRS workflow. E. coli was able to pick up to 7, 5 or 8 resistant phenotypes from a single plasmidome from chicken, cattle or humans, respectively. Resistance to ceftazidime was the most frequently picked up phenotype in humans (52.6%) and cattle (90.5%), whereas in chickens, the most picked up resistant phenotype was resistance to co-trimoxazole, ceftriaxone and ampicillin (18.4% each). Conclusions: This workflow is a novel tool that could facilitate studies to evaluate the occurrence and expression of plasmid-encoded antibiotic resistance in microbial communities and their associated plasmid-host ranges. It could find application in the screening of plasmid-encoded virulence genes.


2003 ◽  
Vol 228 (4) ◽  
pp. 333-344 ◽  
Author(s):  
Karl A. Bettelheim

The problems associated with identification and characterization of non-O157 verotoxin-producing Escherichia coli (VTEC) are discussed. The paradox of VTEC is that most reports of human illnesses are associated with serotypes such as O157:H7, O111:H– (nonmotile), O26:H11, and O113:H21, which are rarely found in domestic animals. However, those VTEC serotypes commonly found in domestic animals, especially ruminants, rarely cause human illnesses. When they cause human illnesses, the symptoms are similar to those caused by the serotypes E. coli O157:H7, O111:H–, O26:H11, and O113:H21. The impact of VTEC on human and animal health is also addressed. The VTEC and their toxicity are considered as a paradigm for emerging pathogens. The question on how such pathogens could arise from a basic commensal population is also addressed.


2008 ◽  
Vol 191 (6) ◽  
pp. 1868-1877 ◽  
Author(s):  
Sivapriya Kailasan Vanaja ◽  
Teresa M. Bergholz ◽  
Thomas S. Whittam

ABSTRACTIntegrating laterally acquired virulence genes into the backbone regulatory network is important for the pathogenesis ofEscherichia coliO157:H7, which has captured many virulence genes through horizontal transfer during evolution. GadE is an essential transcriptional activator of the glutamate decarboxylase (GAD) system, the most efficient acid resistance (AR) mechanism inE. coli. The full contribution of GadE to the AR and virulence ofE. coliO157:H7 remains largely unknown. We inactivatedgadEinE. coliO157:H7 Sakai and compared global transcription profiles of the mutant with that of the wild type in the exponential and stationary phases of growth. Inactivation ofgadEsignificantly altered the expression of 60 genes independently of the growth phase and of 122 genes in a growth phase-dependent manner. Inactivation ofgadEmarkedly downregulated the expression ofgadA, gadB, andgadCand of many acid fitness island genes. Nineteen genes encoded on the locus of enterocyte effacement (LEE), includingler, showed a significant increase in expression upongadEinactivation. Inactivation oflerin the ΔgadEstrain reversed the effect ofgadEdeletion on LEE expression, indicating that Ler is necessary for LEE repression by GadE. GadE is also involved in downregulation of LEE expression under conditions of moderately acidic pH. Characterization of AR of the ΔgadEstrain revealed that GadE is indispensable for a functional GAD system and for survival ofE. coliO157:H7 in a simulated gastric environment. Altogether, these data indicate that GadE is critical for the AR ofE. coliO157:H7 and that it plays an important role in virulence by downregulating expression of LEE.


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