scholarly journals Virulence Factors of Uropathogenic E. coli

Author(s):  
Sorwer Alam Parvez ◽  
Dolilur Rahman
Keyword(s):  
Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 339
Author(s):  
Denise Dekker ◽  
Frederik Pankok ◽  
Thorsten Thye ◽  
Stefan Taudien ◽  
Kwabena Oppong ◽  
...  

Wound infections are common medical problems in sub-Saharan Africa but data on the molecular epidemiology are rare. Within this study we assessed the clonal lineages, resistance genes and virulence factors of Gram-negative bacteria isolated from Ghanaian patients with chronic wounds. From a previous study, 49 Pseudomonas aeruginosa, 21 Klebsiellapneumoniae complex members and 12 Escherichia coli were subjected to whole genome sequencing. Sequence analysis indicated high clonal diversity with only nine P. aeruginosa clusters comprising two strains each and one E. coli cluster comprising three strains with high phylogenetic relationship suggesting nosocomial transmission. Acquired beta-lactamase genes were observed in some isolates next to a broad spectrum of additional genetic resistance determinants. Phenotypical expression of extended-spectrum beta-lactamase activity in the Enterobacterales was associated with blaCTX-M-15 genes, which are frequent in Ghana. Frequently recorded virulence genes comprised genes related to invasion and iron-uptake in E. coli, genes related to adherence, iron-uptake, secretion systems and antiphagocytosis in P. aeruginosa and genes related to adherence, biofilm formation, immune evasion, iron-uptake and secretion systems in K. pneumonia complex. In summary, the study provides a piece in the puzzle of the molecular epidemiology of Gram-negative bacteria in chronic wounds in rural Ghana.


2001 ◽  
Vol 8 (1) ◽  
pp. 143-149 ◽  
Author(s):  
Ulla Niewerth ◽  
Andreas Frey ◽  
Thomas Voss ◽  
Chantal Le Bouguénec ◽  
Georg Baljer ◽  
...  

ABSTRACT Pathogenic Escherichia coli strains are known to cause edema disease (ED) and postweaning diarrhea (PWD) in piglets. Although the exact mechanisms of pathogenicity that lead to ED-PWD remain to be elucidated, E. coli-borne Shiga-like toxin and adhesion-mediating virulence factors such as F18 adhesin or F4 fimbriae are believed to play a central role in ED-PWD. In light of these observations we investigated whether another E. coliadhesin, the plasmid-encoded AIDA (adhesin involved in diffuse adherence) might also be present in ED-PWD-causing E. coli isolates. For rapid screening for the AIDA system in large numbers of isolates, a multiplex PCR method along with a duplex Western blot procedure was developed. When screening 104 strains obtained from pigs with or without ED-PWD, we observed a high prevalence of the AIDA operon in porcine E. coli isolates, with over 25% of all strains being AIDA positive, and we could demonstrate a significant association of the intact AIDA gene (orfB) with ED-PWD, while defects in orfB were associated with the absence of disease. Although our data hint toward a contribution of AIDA to ED-PWD, further studies will be necessary since the presence of the AIDA genes was also associated with the presence of the Shiga-like toxin and F18 adhesin genes, two reported virulence factors for ED-PWD.


Author(s):  
Ayushi Singh ◽  
Daljeet Chhabra ◽  
Rakhi Gangil ◽  
Rakesh Sharda ◽  
Ravi Sikrodia ◽  
...  

Background: Avian colibacillosis is considered as major cause of morbidity and mortality in poultry. It is a common bacterial disease of poultry and many virulence factors of E. coli are associated with the disease. The current study was aimed to investigate the presence of some virulence factors of E. coli isolated from the cases of colibacillosis.Methods: In present study, total 150 samples (liver, heart, lungs, air sacs and feaces) of chicken exhibiting pathological conditions of colibacillosis were collected from various poultry farms (organized and backyard) situated in and around Mhow and Indore cities. E.coli was isolated and identified from the samples on the basis of cultural characteristics and biochemical test. All E. coli isolates were further subjected to evaluate the presence of virulence factors such as biofilm production, haemolysis, invasiveness and molecular detection of fimH and stx1 gene.Result: Out of these 51.33% of incidence of E. coli was recorded. E. coli O84 and O149 serotypes were found most prevalent. Out of 77 isolates, 46 (59.7%) and 45 (58.4%) were positive for biofilm formation by tube method and modified CRA method, respectively. All E. coli isolates were showing invasiveness in congo red binding assay while none of the isolates was found haemolytic. Molecular detection revealed the presence of fimH (508bp) gene in 33.3% of tested samples while stx1 gene could not be detected in any isolates.


2011 ◽  
Vol 80 (2) ◽  
pp. 493-505 ◽  
Author(s):  
Patrick D. Vigil ◽  
Travis J. Wiles ◽  
Michael D. Engstrom ◽  
Lev Prasov ◽  
Matthew A. Mulvey ◽  
...  

ABSTRACTUropathogenicEscherichia coli(UPEC) is responsible for the majority of uncomplicated urinary tract infections (UTI) and represents the most common bacterial infection in adults. UPEC utilizes a wide range of virulence factors to colonize the host, including the novel repeat-in-toxin (RTX) protein TosA, which is specifically expressed in the host urinary tract and contributes significantly to the virulence and survival of UPEC.tosA, found in strains within the B2 phylogenetic subgroup ofE. coli, serves as a marker for strains that also contain a large number of well-characterized UPEC virulence factors. The presence oftosAin anE. coliisolate predicts successful colonization of the murine model of ascending UTI, regardless of the source of the isolate. Here, a detailed analysis of the function oftosArevealed that this gene is transcriptionally linked to genes encoding a conserved type 1 secretion system similar to other RTX family members. TosA localized to the cell surface and was found to mediate (i) adherence to host cells derived from the upper urinary tract and (ii) survival in disseminated infections and (iii) to enhance lethality during sepsis (as assessed in two different animal models of infection). An experimental vaccine, using purified TosA, protected vaccinated animals against urosepsis. From this work, it was concluded that TosA belongs to a novel group of RTX proteins that mediate adherence and host damage during UTI and urosepsis and could be a novel target for the development of therapeutics to treat ascending UTIs.


2016 ◽  
Vol 4 (10) ◽  
pp. 629-638 ◽  
Author(s):  
Armando Navarro ◽  
◽  
CarlosA. Eslava-Campos ◽  
Enrique Melendez-Herrada ◽  
Alejandro Cravioto ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-22 ◽  
Author(s):  
Fernando Navarro-Garcia ◽  
Antonio Serapio-Palacios ◽  
Paul Ugalde-Silva ◽  
Gabriela Tapia-Pastrana ◽  
Lucia Chavez-Dueñas

The actin cytoskeleton is a dynamic structure necessary for cell and tissue organization, including the maintenance of epithelial barriers. Disruption of the epithelial barrier coincides with alterations of the actin cytoskeleton in several disease states. These disruptions primarily affect the paracellular space, which is normally regulated by tight junctions. Thereby, the actin cytoskeleton is a common and recurring target of bacterial virulence factors. In order to manipulate the actin cytoskeleton, bacteria secrete and inject toxins and effectors to hijack the host cell machinery, which interferes with host-cell pathways and with a number of actin binding proteins. An interesting model to study actin manipulation by bacterial effectors isEscherichia colisince due to its genome plasticity it has acquired diverse genetic mobile elements, which allow having differentE. colivarieties in one bacterial species. TheseE. colipathotypes, including intracellular and extracellular bacteria, interact with epithelial cells, and their interactions depend on a specific combination of virulence factors. In this paper we focus onE. colieffectors that mimic host cell proteins to manipulate the actin cytoskeleton. The study of bacterial effector-cytoskeleton interaction will contribute not only to the comprehension of the molecular causes of infectious diseases but also to increase our knowledge of cell biology.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S907-S907
Author(s):  
Teresa C Fox ◽  
Paul Thuras ◽  
Connie Clabots ◽  
Stephen Porter ◽  
James R Johnson

Abstract Background Extraintestinal Escherichia coli infections are an ever-growing threat, to which specific clonal lineages and virulence factors contribute disproportionately. Despite the gut being the main reservoir for such E. coli strains, relationships between clonal lineages, virulence factors, and fecal colonization patterns are poorly understood. Accordingly, we defined E. coli fecal colonization patterns within households (HHs) and assessed specific lineages and virulence genes (VGs) as predictors of colonization behaviors. Methods Veterans with an E. coli clinical isolate (n = 22: 11 fluoroquinoline [FQ]-resistant, 11 FQ-susceptible) and their HH members provided stool samples on 2–6 occasions each. Stools were screened for total and FQ-resistant E. coli. Distinct E. coli strains were resolved by genomic profiling of 10 colonies/sample. Strains underwent molecular lineage identification, VG detection, and comparison with the veteran’s clinical isolate. Clonal lineages and VGs were assessed (Wilcoxon rank-sum test) as predictors of strains’ (i) predominance within the fecal sample, (ii) persistence across serial fecal samples, (iii) within-HH strain sharing, and (iv) overall within-HH colonization prevalence. Results From the 22 veterans and 46 HH members (27 humans, 19 pets) we recovered 139 unique-by-household fecal E. coli strains. Sixty-four traits were evaluated (16 clonal lineages, 48 VGs). Of these, 44 exhibited n ≥ 5, so could be analyzed statistically. Among these 44 traits, the proportion significantly associated with ≥ 1 outcome variable was 5/6 (83%) for clonal lineages and 18/38 (47%) for VGs. Additionally, fecal strains that matched the veteran’s clinical isolate exhibited significantly greater sharing, persistence, and overall colonization. Conclusion The studied E. coli traits – known for their associations with clinical infections –here were significantly associated with within-HH colonization behavior. These findings support that “virulence factors” may be regarded also (or perhaps best) as “colonization factors,” and “virulent lineages” as “colonizing lineages.” This suggests the possibility that future interventions that disrupt colonization behavior also could prevent E. coli infections. Disclosures All authors: No reported disclosures.


2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S337-S338
Author(s):  
Oscar Gomez-Duarte ◽  
Julio Guerra ◽  
Ricky Ko

Abstract Background Enteroinvasive Escherichia coli (EIEC) are involved in dysenteric diarrhea among children in low- and middle-income countries. EIEC strains isolated in Colombia, South America were shown to form biofilms and to be invasive in vitro. The O96:H19 serotypes and biofilm formation (BF) are not common phenotypes among EIEC, and the role they may play in diarrhea is at present unknown. The main goal of this study was to identify virulence and BF genes from EIEC genomic data. We hypothesize that EIEC O96:H19 strain 52.1 originated from horizontal transfer of a Shigella-like virulence plasmid into a non-EIEC pathogenic E coli strain. Methods WGS was performed on the BF-EIEC 52.1 strain using NextGen Illumina and Pacific Biosciences (PacBio) platforms. Publically available genomes from other EIEC O96H19 and Shigella genomes previously published were analyzed using online available software and databases including NCBI, BLAST, Mauve, among others. This analysis was tailored to identify virulence factors from the virulence factor database (VFDB). BLASTn was used to determine identity and query coverage of genes encoding the Shigella virulence factors. EIEC and Shigella genomes were analyzed on a multiple genome alignment software (Mauve) to verify results from BLASTn and to determine pseudogenes. Results The genome of EIEC O96:H19 strain 52.1 was 5,193,449 bp in size, containing 5,050 coding DNA sequences (CDSs). O96:H19 strain 52.1 carries three plasmids, the invasion plasmid (pINV) contains all type 3 secretion system (TTSS) and TTSS effectors genes previously described for Shigella and EIEC O96:H19 CFSAN029787 Italian strain. Non-TTSS virulence genes were also identified, including: long polar fimbrial gene (IpfA), enterotoxin (senB), and antibiotic resistance genes. Conclusion The EIEC O96:H19 strain 52.1 genome carries TTSS genes within a virulence plasmid, protein effector genes, and enterotoxin genes known to be associated with EIEC virulence. The EIEC O96:H19 stain 52.1 is an emergent diarrheagenic pathogen likely derived from an E. coli O96:H19 strain that acquired a Shigella-like virulence plasmid by horizontal transfer. Disclosures All authors: No reported disclosures.


Antibiotics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 152 ◽  
Author(s):  
Ramona Iseppi ◽  
Alessandro Di Cerbo ◽  
Patrizia Messi ◽  
Carla Sabia

Background: We investigated the virulence factors, genes, antibiotic resistance patterns, and genotypes (VRE and ESBL/AmpC) production in Enterococci and Enterobacteriaceae strains isolated from fecal samples of humans, dogs, and cats. Methods: A total of 100 fecal samples from 50 humans, 25 dogs, and 25 cats were used in the study. MICs of nine antimicrobials were determined using the broth microdilution method. Polymerase chain reaction was used for the detection of genes responsible for antibiotic resistance (VRE and ESBL/AmpC) and virulence genes both in Enterococcus species, such as cytolysin (cylA, cylB, cylM), aggregation substance (agg), gelatinase (gelE), enterococcal surface protein (esp), cell wall adhesins (efaAfs and efaAfm), and in Enterobacteriaceae, such as cytolysin (hemolysin) and gelatinase production (afa, cdt, cnf1, hlyA, iutA, papC, sfa). Results: Enterococcus faecium was the most prevalent species in humans and cats, whereas Enterococcus faecalis was the species isolated in the remaining samples. A total of 200 Enterobacteriaceae strains were also detected, mainly from humans, and Escherichia coli was the most frequently isolated species in all types of samples. In the Enterococcus spp, the highest percentages of resistance for ampicillin, amoxicillin/clavulanate, erythromycin, tetracycline, ciprofloxacin, teicoplanin, and vancomycin were detected in cat isolates (41.6%, 52.8%, 38.9%, 23.6%, 62.5%, 20.8%, and 23.6% respectively), and in E. coli, a higher rate of resistance to cefotaxime and ceftazidime emerged in cat and dog samples, if compared with humans (75.4% and 66.0%, 80.0% and 71.4%, and 32.0% and 27.2%, respectively). Regarding the total number of enterococci, 5% and 3.4% of the strains were vancomycin and teicoplanin resistant, and the vancomycin resistance (van A) gene has been detected in all samples by PCR amplification. All the Enterobacteriaceae strains were confirmed as ESBL producers by PCR and sequencing, and the most frequent ESBL genes in E. coli strains from humans and pet samples were blaCTX-M-1 and blaCTX-M-15. Conclusions: Our results provide evidence that one or more virulence factors were present in both genera, underlining again the ability of pet strains to act as pathogens.


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