scholarly journals Genomic characterization of asymptomatic Escherichia coli isolated from the neobladder

Microbiology ◽  
2011 ◽  
Vol 157 (4) ◽  
pp. 1088-1102 ◽  
Author(s):  
Jason W. Sahl ◽  
Amanda L. Lloyd ◽  
Julia C. Redman ◽  
Thomas A. Cebula ◽  
David P. Wood ◽  
...  

The replacement of the bladder with a neobladder made from ileal tissue is the prescribed treatment in some cases of bladder cancer or trauma. Studies have demonstrated that individuals with an ileal neobladder have recurrent colonization by Escherichia coli and other species that are commonly associated with urinary tract infections; however, pyelonephritis and complicated symptomatic infections with ileal neobladders are relatively rare. This study examines the genomic content of two E. coli isolates from individuals with neobladders using comparative genomic hybridization (CGH) with a pan-E. coli/Shigella microarray. Comparisons of the neobladder genome hybridization patterns with reference genomes demonstrate that the neobladder isolates are more similar to the commensal, laboratory-adapted E. coli and a subset of enteroaggregative E. coli than they are to uropathogenic E. coli isolates. Genes identified by CGH as exclusively present in the neobladder isolates among the 30 examined isolates were primarily from large enteric isolate plasmids. Isolations identified a large plasmid in each isolate, and sequencing confirmed similarity to previously identified plasmids of enteric species. Screening, via PCR, of more than 100 isolates of E. coli from environmental, diarrhoeagenic and urinary tract sources did not identify neobladder-specific genes that were widely distributed in these populations. These results taken together demonstrate that the neobladder isolates, while distinct, are genomically more similar to gastrointestinal or commensal E. coli, suggesting why they can colonize the transplanted intestinal tissue but rarely progress to acute pyelonephritis or more severe disease.

2007 ◽  
Vol 189 (9) ◽  
pp. 3532-3546 ◽  
Author(s):  
Amanda L. Lloyd ◽  
David A. Rasko ◽  
Harry L. T. Mobley

ABSTRACT Uropathogenic Escherichia coli (UPEC) strains are responsible for the majority of uncomplicated urinary tract infections, which can present clinically as cystitis or pyelonephritis. UPEC strain CFT073, isolated from the blood of a patient with acute pyelonephritis, was most cytotoxic and most virulent in mice among our strain collection. Based on the genome sequence of CFT073, microarrays were utilized in comparative genomic hybridization (CGH) analysis of a panel of uropathogenic and fecal/commensal E. coli isolates. Genomic DNA from seven UPEC (three pyelonephritis and four cystitis) isolates and three fecal/commensal strains, including K-12 MG1655, was hybridized to the CFT073 microarray. The CFT073 genome contains 5,379 genes; CGH analysis revealed that 2,820 (52.4%) of these genes were common to all 11 E. coli strains, yet only 173 UPEC-specific genes were found by CGH to be present in all UPEC strains but in none of the fecal/commensal strains. When the sequences of three additional sequenced UPEC strains (UTI89, 536, and F11) and a commensal strain (HS) were added to the analysis, 131 genes present in all UPEC strains but in no fecal/commensal strains were identified. Seven previously unrecognized genomic islands (>30 kb) were delineated by CGH in addition to the three known pathogenicity islands. These genomic islands comprise 672 kb of the 5,231-kb (12.8%) genome, demonstrating the importance of horizontal transfer for UPEC and the mosaic structure of the genome. UPEC strains contain a greater number of iron acquisition systems than do fecal/commensal strains, which is reflective of the adaptation to the iron-limiting urinary tract environment. Each strain displayed distinct differences in the number and type of known virulence factors. The large number of hypothetical genes in the CFT073 genome, especially those shown to be UPEC specific, strongly suggests that many urovirulence factors remain uncharacterized.


2021 ◽  
Vol 9 (2) ◽  
pp. 310
Author(s):  
Masayuki Hashimoto ◽  
Yi-Fen Ma ◽  
Sin-Tian Wang ◽  
Chang-Shi Chen ◽  
Ching-Hao Teng

Uropathogenic Escherichia coli (UPEC) is a major bacterial pathogen that causes urinary tract infections (UTIs). The mouse is an available UTI model for studying the pathogenicity; however, Caenorhabditis elegans represents as an alternative surrogate host with the capacity for high-throughput analysis. Then, we established a simple assay for a UPEC infection model with C. elegans for large-scale screening. A total of 133 clinically isolated E. coli strains, which included UTI-associated and fecal isolates, were applied to demonstrate the simple pathogenicity assay. From the screening, several virulence factors (VFs) involved with iron acquisition (chuA, fyuA, and irp2) were significantly associated with high pathogenicity. We then evaluated whether the VFs in UPEC were involved in the pathogenicity. Mutants of E. coli UTI89 with defective iron acquisition systems were applied to a solid killing assay with C. elegans. As a result, the survival rate of C. elegans fed with the mutants significantly increased compared to when fed with the parent strain. The results demonstrated, the simple assay with C. elegans was useful as a UPEC infectious model. To our knowledge, this is the first report of the involvement of iron acquisition in the pathogenicity of UPEC in a C. elegans model.


Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1348
Author(s):  
Lívia Slobodníková ◽  
Barbora Markusková ◽  
Michal Kajsík ◽  
Michal Andrezál ◽  
Marek Straka ◽  
...  

Urinary tract infections (UTIs) are among the events that most frequently need medical intervention. Uropathogenic Escherichia coli are frequently their causative agents and the infections are sometimes complicated by the presence of polyresistant nosocomial strains. Phage therapy is a tool that has good prospects for the treatment of these infections. In the present study, we isolated and characterized two bacteriophages with broad host specificity against a panel of local uropathogenic E. coli strains and combined them into a phage cocktail. According to genome sequencing, these phages were closely related and belonged to the Tequatrovirus genus. The newly isolated phages showed very good activity on a panel of local clinical E. coli strains from urinary tract infections. In the form of a two-phage cocktail, they were active on E. coli strains belonging to phylogroups B2 and D, with relatively lower activity in B1 and no response in phylogroup A. Our study is a preliminary step toward the establishment of a national phage bank containing local, well-characterized phages with therapeutic potential for patients in Slovakia.


2010 ◽  
Vol 5 (6) ◽  
pp. 827-830
Author(s):  
Georgi Slavchev ◽  
Nadya Markova

AbstractUropathogenic strains of E. coli isolated from urine of patients with urinary tract infections were tested for antibiotic sensitivity using bio-Merieux kits and ATB-UR 5 expression system. The virulence of strains was evaluated by serum bactericidal assay, macrophage “killing” and bacterial adhesive tests. Survival capability of strains was assessed under starvation in saline. The results showed that quinolone-resistant uropathogenic strains of E. coli exhibit significantly reduced adhesive potential but relatively high resistance to serum and macrophage bactericidity. In contrast to laboratory strains, the quinolone-resistant uropathogenic clinical isolate demonstrated increased viability during starvation in saline. Our study suggests that quinolone-resistant uropathogenic strains are highly adaptable clones of E. coli, which can exhibit compensatory viability potential under unfavorable conditions. The clinical occurrence of such phenotypes is likely to contribute to the survival, persistence and spread strategy of resistant bacteria.


mBio ◽  
2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Dana Willner ◽  
Serene Low ◽  
Jason A. Steen ◽  
Narelle George ◽  
Graeme R. Nimmo ◽  
...  

ABSTRACTUrinary tract infections (UTIs) are one of the most commonly acquired bacterial infections in humans, and uropathogenicEscherichia colistrains are responsible for over 80% of all cases. The standard method for identification of uropathogens in clinical laboratories is cultivation, primarily using solid growth media under aerobic conditions, coupled with morphological and biochemical tests of typically a single isolate colony. However, these methods detect only culturable microorganisms, and characterization is phenotypic in nature. Here, we explored the genotypic identity of communities in acute uncomplicated UTIs from 50 individuals by using culture-independent amplicon pyrosequencing and whole-genome and metagenomic shotgun sequencing. Genus-level characterization of the UTI communities was achieved using the 16S rRNA gene (V8 region). Overall UTI community richness was very low in comparison to other human microbiomes. We strain-typedEscherichia-dominated UTIs using amplicon pyrosequencing of the fimbrial adhesin gene,fimH. There were nine highly abundantfimHtypes, and each UTI sample was dominated by a single type. Molecular analysis of the corresponding clinical isolates revealed that in the majority of cases the isolate was representative of the dominant taxon in the community at both the genus and the strain level. Shotgun sequencing was performed on a subset of eightE. coliurine UTI and isolate pairs. The majority of UTI microbial metagenomic sequences mapped to isolate genomes, confirming the results obtained using phylogenetic markers. We conclude that for the majority of acute uncomplicatedE. coli-mediated UTIs, single cultured isolates are diagnostic of the infection.IMPORTANCEIn clinical practice, the diagnosis and treatment of acute uncomplicated urinary tract infection (UTI) are based on analysis of a single bacterial isolate cultured from urine, and it is assumed that this isolate represents the dominant UTI pathogen. However, these methods detect only culturable bacteria, and the existence of multiple pathogens as well as strain diversity within a single infection is not examined. Here, we explored bacteria present in acute uncomplicated UTIs using culture-independent sequence-based methods.Escherichia coliwas the most common organism identified, and analysis ofE. colidominant UTI samples and their paired clinical isolates revealed that in the majority of infections the cultured isolate was representative of the dominant taxon at both the genus and the strain level. Our data demonstrate that in most cases single cultured isolates are diagnostic of UTI and are consistent with the notion of bottlenecks that limit strain diversity during UTI pathogenesis.


2005 ◽  
Vol 49 (6) ◽  
pp. 2343-2351 ◽  
Author(s):  
Patricia Komp Lindgren ◽  
Linda L. Marcusson ◽  
Dorthe Sandvang ◽  
Niels Frimodt-Møller ◽  
Diarmaid Hughes

ABSTRACT Resistance to fluoroquinolones in urinary tract infection (UTIs) caused by Escherichia coli is associated with multiple mutations, typically those that alter DNA gyrase and DNA topoisomerase IV and those that regulate AcrAB-TolC-mediated efflux. We asked whether a fitness cost is associated with the accumulation of these multiple mutations. Mutants of the susceptible E. coli UTI isolate Nu14 were selected through three to five successive steps with norfloxacin. Each selection was performed with the MIC of the selected strain. After each selection the MIC was measured; and the regions of gyrA, gyrB, parC, and parE, previously associated with resistance mutations, and all of marOR and acrR were sequenced. The first selection step yielded mutations in gyrA, gyrB, and marOR. Subsequent selection steps yielded mutations in gyrA, parE, and marOR but not in gyrB, parC, or acrR. Resistance-associated mutations were identified in almost all isolates after selection steps 1 and 2 but in less than 50% of isolates after subsequent selection steps. Selected strains were competed in vitro, in urine, and in a mouse UTI infection model against the starting strain, Nu14. First-step mutations were not associated with significant fitness costs. However, the accumulation of three or more resistance-associated mutations was usually associated with a large reduction in biological fitness, both in vitro and in vivo. Interestingly, in some lineages a partial restoration of fitness was associated with the accumulation of additional mutations in late selection steps. We suggest that the relative biological costs of multiple mutations may influence the evolution of E. coli strains that develop resistance to fluoroquinolones.


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.


Author(s):  
Rachana Kanaujia ◽  
Amit Kumar ◽  
Malay Bajpai

Background: Urinary tract infections (UTIs) are one of the most common infections. For treatment of UTIs, there are limited antibiotics due to increased resistance among uropathogens. Two older antibiotics; Nitrofurantoin and Fosfomycin have become novel oral therapeutic options against uropathogens. Aim of the study was to identify UTI causing micro-organisms and evaluate in-vitro activity of nitrofurantoin and fosfomycin against most common isolated organism (E. coli).Methods: Results of urine samples culture and susceptibility testing over a period of 1 year were analysed and included in this study.Results: Micro-organisms were isolated from 568 urine samples. Most commonly isolated organism was Escherichia coli (40.50%), followed by Klebsiella spp. (20.07%) and Staphylococcus spp. (17.07%). Susceptibility of E. coli to nitrofurantoin and fosfomycin was 91.74% and 65.65% respectively. Conclusion: Good activity of nitrofurantoin and fosfomycin against E. coli indicates that these two drugs are potential therapeutic alternatives for urinary tract infections.


1998 ◽  
Vol 66 (8) ◽  
pp. 3856-3861 ◽  
Author(s):  
A. E. Stapleton ◽  
M. R. Stroud ◽  
S. I. Hakomori ◽  
W. E. Stamm

ABSTRACT Women with a history of recurrent Escherichia coliurinary tract infections (UTIs) are significantly more likely to be nonsecretors of blood group antigens than are women without such a history, and vaginal epithelial cells (VEC) from women who are nonsecretors show enhanced adherence of uropathogenic E. coli isolates compared with cells from secretors. We previously extracted glycosphingolipids (GSLs) from native VEC and determined that nonsecretors (but not secretors) selectively express two extended globoseries GSLs, sialosyl galactosyl globoside (SGG) and disialosyl galactosyl globoside (DSGG), which specifically bound uropathogenicE. coli R45 expressing a P adhesin. In this study, we demonstrated, by purifying the compounds from this source, that SGG and DSGG are expressed in human kidney tissue. We also demonstrated that SGG and DSGG isolated from human kidneys bind uropathogenic E. coli isolates expressing each of the three classes ofpap-encoded adhesins, including cloned isolates expressing PapG from J96, PrsG from J96, and PapG from IA2, and the wild-type isolates IA2 and R45. We metabolically 35S labeled these five E. coli isolates and measured their relative binding affinities to serial dilutions of SGG and DSGG as well as to globotriaosylceramide (Gb3) and globotetraosylceramide (Gb4), two other globoseries GSLs present in urogenital tissues. Each of the five E. coli isolates bound to SGG with the highest apparent avidity compared with their binding to DSGG, Gb3, and Gb4, and each isolate had a unique pattern of GSL binding affinity. These studies further suggest that SGG likely plays an important role in the pathogenesis of UTI and that its presence may account for the increased binding of E. colito uroepithelial cells from nonsecretors and for the increased susceptibility of nonsecretors to recurrent UTI.


2020 ◽  
Author(s):  
Mohammad Hasan Namaei ◽  
Hengameh Hamzei ◽  
Marzie Moghanni ◽  
Azadeh Ebrahimzadeh

Abstract Background: Urinary Tract Infection (UTI) is the most common bacterial infection in the world. E. coli is the predominant Pathogen. This study evaluates the prevalence of ESBL in E. colis isolated from patients with urinary tract infections with phenotypic and genotypic methods.Methods: This descriptive-analytical study was done on 155 isolates of E. coli isolated from patients with urinary tract infection who had received the study consent. After accurate identification of E. coli strains. ESBL production for Escherichia coli isolates which are resistant to ceftriaxone or ceftazidime was evaluated by CDT method. TEM, SHV and CTX-M genes were identified by PCR.Results: The results showed that 30 strains from 155 strains of E. coli had ESBL. Strains of ESBL producer were more in males was lower in educated persons. 38.9% of ESBL producer had antibiotic use, 29.9% -producing Escherichia hospitalization and 31.6% uti history. The highest level of drug allergy in the ESBL was related to nitrofurantoin, and the highest resistance was related to cefazolin, co-trimoxazole. The CTX-M and the CTX-M15 gene were found in 92.7% and 57.1% of cases, respectively; also the SHV and TEM genes were not found in any of ESBL-producing Escherichia coli strains. Most therapeutic response in patients was related to cefexime, ciprofloxacin and nitrofurantoin 27.4%, 26% 21.9%, respectively.Conclusion: This study showed that the history of antibiotic use, hospitalization, uti related to increase of ESBL-producing in E. coli isolates., the CTMX-M gene is the most common gene in ESBL-producing E. coli strains.


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