scholarly journals Genotypic characterization of virulence factors in Escherichia coli strains from patients with cystitis

2008 ◽  
Vol 50 (5) ◽  
pp. 255-260 ◽  
Author(s):  
Monique Ribeiro Tiba ◽  
Tomomasa Yano ◽  
Domingos da Silva Leite
Keyword(s):  
Escherichia Coli ◽  
Iron Acquisition ◽  
Uropathogenic Escherichia Coli ◽  
Pcr Assay ◽  
Single Strain ◽  
Polymerase Chain ◽  
Factor Type ◽  
Tract Infections

Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (α-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.

scholarly journals Genotypic Study of Two Virulence Factors fimH and kpsMTII in Uropathogenic Escherichia coli Isolates from Children Patients with Urinary Tract Infections

2014 ◽  
Vol 11 (4) ◽  
pp. 1475-1480
Author(s):  
Baghdad Science Journal
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Host Defense ◽  
Uropathogenic Escherichia Coli ◽  
Chain Reaction ◽  
Pcr Assay ◽  
Polymerase Chain ◽  
Tract Infections

Adhesion (type 1 fimbriae) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli isolates associated with urinary tract infections. In this work, 50 uropathogenic Escherichia coli (UPEC) isolated from children with urinary tract infections were genotypically characterized by polymerase chain reaction (PCR) assay. We used two genes; fimH and kpsMTII, both of them previously identified in uropathogenic E.coli (UPEC) isolates. The PCR assay results identified fimH (90.0)% and kpsMTII (72.0)% isolates. In the present study, was also demonstrated that these genes may be included in both or one of them within a single isolate.

Molecular Analysis of Uropathogenic E.coli Isolates from Urinary Tract Infections

2019 ◽  
Vol 19 (3) ◽  
pp. 322-326 ◽  
Author(s):  
Hassan Valadbeigi ◽  
Elham Esmaeeli ◽  
Sobhan Ghafourian ◽  
Abbas Maleki ◽  
Nourkhoda Sadeghifard
Keyword(s):  
Escherichia Coli ◽  
Polymerase Chain Reaction ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Multiplex Polymerase Chain Reaction ◽  
Virulence Genes ◽  
Uropathogenic Escherichia Coli ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Tract Infections

Introduction: The aim of the current study was to investigate the prevalence of virulence genes in uropathogenic Escherichia coli (UPEC) isolates in Ilam. Materials and Methods: For this purpose, a total of 80 UPEC isolates were collected for patients with UTIs during a 6 months period. The multiplex polymerase chain reaction (multiplex PCR) was used to detect the papEF, fimH, iucD, hlyA, fyuA, and ompT genes. Results: The prevalence of fimH, papEF, iucD, fyuA, hlyA, hlyA, and ompT genes were 87.5%, 47.5%, 60%, 67.5%, 27.5%, 47.5% and 71.2%, respectively. Among all of the isolates, 27 profiles were obtained. Conclusion: Our findings demonstrated that the most prevalence was found for fimH, and different distribution of virulence genes suggested different ability of pathogenicity.

scholarly journals Comprehensive Identification of Fim-Mediated Inversions in Uropathogenic Escherichia coli with Structural Variation Detection Using Relative Entropy

2018 ◽  
Author(s):  
Colin W. Russell ◽  
Rashmi Sukumaran ◽  
Lu Ting Liow ◽  
Balamurugan Periaswamy ◽  
Shazmina Rafee ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Relative Entropy ◽  
Structural Variation ◽  
Infection Type ◽  
Uropathogenic Escherichia Coli ◽  
Structural Variations ◽  
Type 1 Pili ◽  
Bladder Cells ◽  
Tract Infections

Most urinary tract infections (UTIs) are caused by uropathogenic Escherichia coli (UPEC), which depend on an extracellular organelle (Type 1 pili) for adherence to bladder cells during infection. Type 1 pilus expression is partially regulated by inversion of a piece of DNA referred to as fimS, which contains the promoter for the fim operon encoding Type 1 pili. fimS inversion is regulated by up to five recombinases collectively known as Fim recombinases. These Fim recombinases are currently known to regulate two other switches: the ipuS and hyxS switches. A long-standing question has been whether the Fim recombinases regulate the inversion of other switches, perhaps to coordinate expression for adhesion or virulence. We answered this question using whole genome sequencing with a newly developed algorithm (Structural Variation detection using Relative Entropy, SVRE) for calling structural variations using paired-end short read sequencing. SVRE identified all of the previously known switches, refining the specificity of which recombinases act at which switches. Strikingly, we found no new inversions that were mediated by the Fim recombinases. We conclude that the Fim recombinases are each highly specific for a small number of switches. We hypothesize that the unlinked Fim recombinases have been recruited to regulate fimS, and fimS only, as a secondary locus; this further implies that regulation of Type 1 pilus expression (and its role in gastrointestinal and/or genitourinary colonization) is important enough, on its own, to influence the evolution and maintenance of multiple additional genes within the accessory genome of E. coli.

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

2019 ◽  
Vol 13 (06) ◽  
pp. 465-472
Author(s):  
Ulises Hernández-Chiñas ◽  
Alejandro Pérez-Ramos ◽  
Laura Belmont-Monroy ◽  
María E Chávez-Berrocal ◽  
Edgar González-Villalobos ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Antimicrobial Agents ◽  
Multidrug Resistant ◽  
Uropathogenic Escherichia Coli ◽  
E Coli ◽  
Resistant Strains ◽  
Tract Infections ◽  
Disk Method

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

scholarly journals Molecular Characterization of Uropathogenic Escherichia coli Reveals Emergence of Drug Resistant O15, O22 and O25 Serogroups

Medicina ◽  
2019 ◽  
Vol 55 (11) ◽  
pp. 733 ◽  
Author(s):  
Ruta Prakapaite ◽  
Frederic Saab ◽  
Rita Planciuniene ◽  
Vidmantas Petraitis ◽  
Thomas J. Walsh ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Asymptomatic Bacteriuria ◽  
Empirical Therapy ◽  
Uropathogenic Escherichia Coli ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Tract Infections ◽  
Resistance Rates

Background and Objectives: Uropathogenic Escherichia coli (UPEC) are common pathogens causing urinary tract infections (UTIs). We aimed to investigate the relationship among clinical manifestation, serogroups, phylogenetic groups, and antimicrobial resistance among UPEC. Materials and Methods: One-hundred Escherichia coli isolates recovered from urine and ureteral scrapings were used for the study. The prevalence of antimicrobial resistance was determined by using European Committee on Antimicrobial Susceptibility Testing (EUCAST) recommendations. E. coli serogroups associated with UTI, as well as phylogenetic diversity were analyzed using multiplex PCR reactions. Results: Eighty-seven strains (87%) were isolated from females, while 13 (13%) from males. A high frequency of resistance to cephalosporins (43%) and fluoroquinolones (31%) was observed. Among UTI-associated serogroups O15 (32.8%), O22 (23.4%), and O25 (15.6%) were dominant and demonstrated elevated resistance rates. The E. coli phylogenetic group B2 was most common. These observations extended to pregnant patients with asymptomatic bacteriuria. Conclusions: Due to high rates of resistance, strategies using empirical therapy of second-generation cephalosporins and fluoroquinolones should be reconsidered in this population.

scholarly journals Characterization of Fosfomycin and Nitrofurantoin Resistance Mechanisms in Escherichia coli Isolated in Clinical Urine Samples

Antibiotics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 534
Author(s):  
Antonio Sorlozano-Puerto ◽  
Isaac Lopez-Machado ◽  
Maria Albertuz-Crespo ◽  
Luis Javier Martinez-Gonzalez ◽  
Jose Gutierrez-Fernandez
Keyword(s):  
Escherichia Coli ◽  
Resistance Genes ◽  
Resistance Mechanisms ◽  
Surveillance Studies ◽  
Epidemiologic Surveillance ◽  
Genetic Mechanisms ◽  
Polymerase Chain ◽  
Plasmid Genes ◽  
Tract Infections

Fosfomycin and nitrofurantoin are antibiotics of choice to orally treat non-complicated urinary tract infections (UTIs) of community origin because they remain active against bacteria resistant to other antibiotics. However, epidemiologic surveillance studies have detected a reduced susceptibility to these drugs. The objective of this study was to determine possible mechanisms of resistance to these antibiotics in clinical isolates of fosfomycin- and/or nitrofurantoin-resistant UTI-producing Escherichia coli. We amplified and sequenced murA, glpT, uhpT, uhpA, ptsI, cyaA, nfsA, nfsB, and ribE genes, and screened plasmid-borne fosfomycin-resistance genes fosA3, fosA4, fosA5, fosA6, and fosC2 and nitrofurantoin-resistance genes oqxA and oqxB by polymerase chain reaction. Among 29 isolates studied, 22 were resistant to fosfomycin due to deletion of uhpT and/or uhpA genes, and 2 also possessed the fosA3 gene. Some modifications detected in sequences of NfsA (His11Tyr, Ser33Arg, Gln67Leu, Cys80Arg, Gly126Arg, Gly154Glu, Arg203Cys), NfsB (Gln44His, Phe84Ser, Arg107Cys, Gly192Ser, Arg207His), and RibE (Pro55His), and the production of truncated NfsA (Gln67 and Gln147) and NfsB (Glu54), were associated with nitrofurantoin resistance in 15/29 isolates; however, the presence of oqxAB plasmid genes was not detected in any isolate. Resistance to fosfomycin was associated with the absence of transporter UhpT expression and/or the presence of antibiotic-modifying enzymes encoded by fosA3 plasmid-mediated gene. Resistance to nitrofurantoin was associated with modifications of NfsA, NfsB, and RibE proteins. The emergence and spread of these resistance mechanisms, including transferable resistance, could compromise the future usefulness of fosfomycin and nitrofurantoin against UTIs. Furthermore, knowledge of the genetic mechanisms underlying resistance may lead to rapid DNA-based testing for resistance.

scholarly journals Mutation of the Gene Encoding Cytotoxic Necrotizing Factor Type 1 (cnf1) Attenuates the Virulence of Uropathogenic Escherichia coli

2001 ◽  
Vol 69 (6) ◽  
pp. 3954-3964 ◽  
Author(s):  
Karen E. Rippere-Lampe ◽  
Alison D. O'Brien ◽  
Richard Conran ◽  
Hank A. Lockman
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Human Neutrophils ◽  
Wild Type ◽  
Single Strain ◽  
E Coli ◽  
Cytotoxic Necrotizing Factor ◽  
Positive Strain ◽  
Factor Type

ABSTRACT Cytotoxic necrotizing factor type 1 (CNF1) is a 115-kDa toxin that activates Rho GTPases and is produced by uropathogenicEscherichia coli (UPEC). While both epidemiological studies that link CNF1 production by E. coli with urinary tract disease and the cytopathic effects of CNF1 on cultured urinary tract cells are suggestive of a role for the toxin as a UPEC virulence factor, few in vivo studies to test this possibility have been reported. Therefore, in this investigation, we evaluated the importance of CNF1 in a murine model of urinary tract infection (UTI) by comparing the degree of colonization and damage induced by three different CNF1-producing E. coli strains with isogenic CNF1-deficient derivatives. The data from single-strain challenge experiments with C3H/HeOuJ mice indicated a trend toward higher counts of the wild-type strains in the urine and bladders of these animals up to 3 days after challenge in two of three strain pairs. Furthermore, this difference was statistically significant at day 2 of infection with one strain pair, C189 and C189cnf 1. To control for the animal-to-animal variability inherent in this model, we infected C3H/HeOuJ mice with a mixture of CNF1-positive and -negative isogenic derivatives of CP9. The CNF1-positive strain was recovered in higher numbers than the CNF1-negative strain in the urine, bladders, and kidneys of the mice up to 9 days postinfection. These striking coinfection findings, taken with the trends observed in single-strain infections, led us to conclude that CNF1-negative strains were generally attenuated compared to the wild type in the C3H/HeOuJ mouse model of UTI. Furthermore, histopathological examination of bladder specimens from mice infected with CNF1-positive strains consistently showed deeper, more extensive inflammation than in those infected with the isogenic mutants. Lastly, we found that CNF1-positive strain CP9 was better able to resist killing by fresh human neutrophils than were CP9cnf 1 bacteria. From these data in aggregate, we propose that CNF1 production increases the capacity of UPEC strains to resist killing by neutrophils, which in turn permits these bacteria to gain access to deeper tissue and persist better in the lower urinary tract.

scholarly journals Cytotoxic Necrotizing Factor Type 1 of Uropathogenic Escherichia coli Kills Cultured Human Uroepithelial 5637 Cells by an Apoptotic Mechanism

2000 ◽  
Vol 68 (10) ◽  
pp. 5869-5880 ◽  
Author(s):  
Melody Mills ◽  
Karen C. Meysick ◽  
Alison D. O'Brien
Keyword(s):  
Escherichia Coli ◽  
Cell Line ◽  
Cell Lines ◽  
Human Bladder ◽  
E Coli ◽  
Cytotoxic Necrotizing Factor ◽  
Bladder Cell ◽  
Factor Type ◽  
Tract Infections

ABSTRACT Pathogenic Escherichia coli associated with urinary tract infections (UTIs) in otherwise healthy individuals frequently produce cytotoxic necrotizing factor type 1 (CNF1), a member of the family of bacterial toxins that target the Rho family of small GTP-binding proteins. To gain insight into the function of CNF1 in the development of E. coli-mediated UTIs, we examined the effects of CNF1 intoxication on a panel of human cell lines derived from physiologically relevant sites (bladder, ureters, and kidneys). We identified one uroepithelial cell line that exhibited a distinctly different CNF1 intoxication phenotype from the prototypic one of multinucleation without cell death that is seen when HEp-2 or other epithelial cells are treated with CNF1. The 5637 bladder cell line detached from the growth surface within 72 h of CNF1 intoxication, a finding that suggested frank cytotoxicity. To determine the basis for the unexpected toxic effect of CNF1 on 5637 cells, we compared the degree of toxin binding, actin fiber formation, and Rho modification with those CNF1-induced events in HEp-2 cells. We found no apparent difference in the amount of CNF1 bound to 5637 cells and HEp-2 cells. Moreover, CNF1 modified Rho, in vivo and in vitro, in both cell types. In contrast, one of the classic responses to CNF1 in HEp-2 and other epithelial cell lines, the formation of actin stress fibers, was markedly absent in 5637 cells. Indeed, actin stress fiber induction by CNF1 did not occur in any of the other human bladder cell lines that we tested (J82, SV-HUC-1, or T24). Furthermore, the appearance of lamellipodia and filopodia in 5637 cells suggested that CNF1 activated the Cdc42 and Rac proteins. Finally, apoptosis was observed in CNF1-intoxicated 5637 cells. If our results with 5637 cells reflect the interaction of CNF1 with the transitional uroepithelium in the human bladder, then CNF1 may be involved in the exfoliative process that occurs in that organ after infection with uropathogenic E. coli.

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