tRNA genes and pathogenicity islands: influence on virulence and metabolic properties of uropathogenic Escherichia coli

Background: Uropathogenic Escherichia coli (UPEC) is one of the most common etiologic agent of urinary tract infection (UTI). The ability of Escherichia coli to cause UTI is associated with specific virulence determinants, which are encoded by pathogenicity islands (PAIs). Objectives: This study aimed to investigate the distribution of PAIs among the UPEC isolates collected from patients with UTIs. Materials and Methods: In this study, a total of 100 E. coli isolates were collected from patients with UTIs using standard microbiological methods. Polymerase chain reaction (PCR) was used for the identification of the main PAIs of UPEC according to insertion sites and virulence markers. Results: In total, PAI IV536, PAI III536, PAI I536, PAI, IICFT073, PAI ICFT073, PAI IIJ96, PAI II536, and PAI IJ96 were detected in 23, 22, 17, 17, 13, 11, 11, and 8% of isolates. PAI combinations were identified in 15% of isolates. Conclusion: The results showed that PAIs of UPEC are not strain-specific and some strains can carry the PAIs associated with the prototype strains of UPEC simultaneously.

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Evaluation of pathogenicity islands in uropathogenic Escherichia coli isolated from patients with urinary catheters

The Journal of Infection in Developing Countries ◽

10.3855/jidc.8660 ◽

2017 ◽

Vol 11 (07) ◽

pp. 557-562 ◽

Cited By ~ 1

Author(s):

Farzaneh Firoozeh ◽

Leila Soleimani-Moorchekhorti ◽

Mohammad Zibaei

Keyword(s):

Escherichia Coli ◽

Cross Sectional Study ◽

Uropathogenic Escherichia Coli ◽

Pathogenicity Islands ◽

Urinary Catheters ◽

Cross Sectional ◽

Indwelling Catheters ◽

Medical Interventions ◽

Urinary Infections ◽

Tract Infections

Introduction: Uropathogenic Escherichia coli (UPEC), an important causative agent of urinary tract infections (UTIs), carries virulence factors which are clustered on pathogenicity islands (PAIs). The goal of this study was to characterize the PAIs among the UPEC isolated from patients with urinary catheters. Methodology: A descriptive cross-sectional study was designed and from December 2014 to April 2015, 78 non-duplicate E. coli were collected from hospitalized patients with UTIs, including patients with and without indwelling urinary catheters. Two multiplex polymerase chain reaction (PCR) assays were performed to evaluate the presence of the eight most studied PAIs (I 536, II 536, III 536, IV536, I CFT073, II CFT073, PAI IJ96, and PAI IIJ96). Results: Of 78 patients with a UTI 31 (39.7%) used indwelling catheters. Of these 31 patients, 27 (87.1%) carried PAIs markers, including 25 (80.6%) PAI IV536, 12 (38.7%) PAI ICFT073, 6 (19.4%) PAI IICFT073, 6 (19.4%) PAI III536 and 3 (9.7%) PAI II536. PAI I536, PAI IJ96, and PAI IIJ96 were not detected in the UPEC strains. Conclusions: The findings of this study revealed that the frequency of PAI markers in UPEC isolates from patients with indwelling urinary catheters was high. The rate of multiple PAIs carriage was notable among those patients, suggesting that UPEC strains that colonize the indwelling urinary catheters have the potential to cause complicated urinary infections. PAI ICFT073, which was found in association with pyelonephritis, prostatitis, and sepsis, could be considered as a target for medical interventions.

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Molecular investigation of tRNA genes integrity and its relation to pathogenicity islands in Shiga toxin-producing Escherichia coli (STEC) strains

Genetics and Molecular Biology ◽

10.1590/s1415-47572004000400020 ◽

2004 ◽

Vol 27 (4) ◽

pp. 589-593

Author(s):

Rogério Carlos Novais ◽

Marcela Cassin Chaves ◽

Alice Gonçalves Martins Gonzalez ◽

João Ramos Costa Andrade

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Pathogenicity Islands ◽

Trna Genes ◽

Molecular Investigation

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Genome-Based Identification of Chromosomal Regions Specific for Salmonella spp.

Infection and Immunity ◽

10.1128/iai.70.5.2351-2360.2002 ◽

2002 ◽

Vol 70 (5) ◽

pp. 2351-2360 ◽

Cited By ~ 36

Author(s):

Imke Hansen-Wester ◽

Michael Hensel

Keyword(s):

Escherichia Coli ◽

Horizontal Gene Transfer ◽

Virulence Genes ◽

Bacterial Species ◽

Pathogenicity Islands ◽

Trna Genes ◽

Comparative Genome Analysis ◽

Salmonella Spp ◽

Heterogeneous Distribution ◽

Species Specific

ABSTRACT Acquisition of genomic elements by horizontal gene transfer represents an important mechanism in the evolution of bacterial species. Pathogenicity islands are a subset of horizontally acquired elements present in various pathogens. These elements are frequently located adjacent to tRNA genes. We performed a comparative genome analysis of Salmonella enterica serovars Typhi and Typhimurium and Escherichia coli and scanned tRNA loci for the presence of species-specific, horizontally acquired genomic elements. A large number of species-specific elements were identified. Here, we describe the characteristics of four large chromosomal insertions at tRNA genes of Salmonella spp. The tRNA-associated elements harbor various genes previously identified as single virulence genes, indicating that these genes have been acquired with large chromosomal insertions. Southern blot analyses confirmed that the tRNA-associated elements are specific to Salmonella and also indicated a heterogeneous distribution within the salmonellae. Systematic scanning for insertions at tRNA genes thus represents a tool for the identification of novel pathogenicity islands.

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