The IrgA Homologue Adhesin Iha Is an Escherichia coli Virulence Factor in Murine Urinary Tract Infection

ABSTRACT The role of the Escherichia coli iron-regulated gene homologue adhesin (Iha) in the pathogenesis of urinary tract infections (UTIs) is unknown. We performed a series of complementary analyses to confirm or refute the hypothesis that Iha is a virulence factor in uropathogenic E. coli. Fecal E. coli isolates exhibited significantly lower prevalences of iha (range, 14 to 22%) than did clinical isolates from cases of pediatric cystitis or pyelonephritis, adult pyelonephritis or urosepsis, or bacteremia (range, 38 to 74%). Recombinant Iha from E. coli pyelonephritis isolate CFT073 conferred upon nonadherent E. coli ORN172 the ability to adhere to cultured T-24 human uroepithelial cells. In a well-established mouse model of ascending UTI, CFT073 and its derivative UPEC76 (a pap [P fimbriae] mutant version of strain CFT073) each significantly outcompeted their respective iha deletion mutants in CBA/J mice 48 h after bladder challenge (P < 0.03 for urine, both kidneys, and bladders of both constructs, except for bladders of mice challenged with UPEC76 and its deletion mutant, where P = 0.11). These data suggest that IhaCFT073 is a virulence factor and might be a target for anti-UTI interventions.

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Adhesion of Escherichia Coli to Nanostructured Surfaces and the Role of Type 1 Fimbriae

Nanomaterials ◽

10.3390/nano10112247 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2247

Author(s):

Pawel Kallas ◽

Håvard J Haugen ◽

Nikolaj Gadegaard ◽

John Stormonth-Darling ◽

Mats Hulander ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Virulence Factor ◽

Wild Type ◽

E Coli ◽

Type 1 Fimbriae ◽

Tract Infections

Bacterial fimbriae are an important virulence factor mediating adhesion to both biotic and abiotic surfaces and facilitating biofilm formation. The expression of type 1 fimbriae of Escherichia coli is a key virulence factor for urinary tract infections and catheter-associated urinary tract infections, which represent the most common nosocomial infections. New strategies to reduce adhesion of bacteria to surfaces is therefore warranted. The aim of the present study was to investigate how surfaces with different nanotopography-influenced fimbriae-mediated adhesion. Surfaces with three different nanopattern surface coverages made in polycarbonate were fabricated by injection molding from electron beam lithography nanopatterned templates. The surfaces were constructed with features of approximately 40 nm width and 25 nm height with 100 nm, 250 nm, and 500 nm interspace distance, respectively. The role of fimbriae type 1-mediated adhesion was investigated using the E. coli wild type BW25113 and ΔfimA (with a knockout of major pilus protein FimA) and ΔfimH (with a knockout of minor protein FimH) mutants. For the surfaces with nanotopography, all strains adhered least to areas with the largest interpillar distance (500 nm). For the E. coli wild type, no difference in adhesion between surfaces without pillars and the largest interpillar distance was observed. For the deletion mutants, increased adhesion was observed for surfaces without pillars compared to surfaces with the largest interpillar distance. The presence of a fully functional type 1 fimbria decreased the bacterial adhesion to the nanopatterned surfaces in comparison to the mutants.

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Role of Motility in the Colonization of Uropathogenic Escherichia coli in the Urinary Tract

Infection and Immunity ◽

10.1128/iai.73.11.7644-7656.2005 ◽

2005 ◽

Vol 73 (11) ◽

pp. 7644-7656 ◽

Cited By ~ 144

Author(s):

M. Chelsea Lane ◽

Virginia Lockatell ◽

Greta Monterosso ◽

Daniel Lamphier ◽

Julia Weinert ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Wild Type Strain ◽

Uropathogenic Escherichia Coli ◽

Wild Type ◽

Upec Strain ◽

Host Immune Responses ◽

Strain Cft073 ◽

Tract Infections

ABSTRACT Uropathogenic Escherichia coli (UPEC) causes most uncomplicated urinary tract infections (UTIs) in humans. Flagellum-mediated motility and chemotaxis have been suggested to contribute to virulence by enabling UPEC to escape host immune responses and disperse to new sites within the urinary tract. To evaluate their contribution to virulence, six separate flagellar mutations were constructed in UPEC strain CFT073. The mutants constructed were shown to have four different flagellar phenotypes: fliA and fliC mutants do not produce flagella; the flgM mutant has similar levels of extracellular flagellin as the wild type but exhibits less motility than the wild type; the motAB mutant is nonmotile; and the cheW and cheY mutants are motile but nonchemotactic. Virulence was assessed by transurethral independent challenges and cochallenges of CBA mice with the wild type and each mutant. CFU/ml of urine or CFU/g bladder or kidney was determined 3 days postinoculation for the independent challenges and at 6, 16, 48, 60, and 72 h postinoculation for the cochallenges. While these mutants colonized the urinary tract during independent challenge, each of the mutants was outcompeted by the wild-type strain to various degrees at specific time points during cochallenge. Altogether, these results suggest that flagella and flagellum-mediated motility/chemotaxis may not be absolutely required for virulence but that these traits contribute to the fitness of UPEC and therefore significantly enhance the pathogenesis of UTIs caused by UPEC.

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Involvement of biofilm-like in tracellular bacterial communities of uropathogenic Escherichia coli in pathogenesis of urinary tract infections – a mini review

Current Issues in Pharmacy and Medical Sciences ◽

10.12923/j.2084-980x/26.3/a.18 ◽

2013 ◽

Vol 26 (3) ◽

pp. 321-325

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Bacterial Communities ◽

Uropathogenic Escherichia Coli ◽

E Coli ◽

Etiologic Agents ◽

Tract Infections ◽

Intracellular Bacterial Communities

This paper presents a precisely defined question about the role of the biofilm-like intracellular bacterial communities in pathogenesis of the urinary tract infections. According to the recent literature, uropathogenic Escherichia coli is one of the leading etiologic agents of the urinary tract infections. Although E. coli is regarded as an extracellular pathogen, some experiments have revealed a multi-step infection cycle, which involves adhesion, invasion, proliferation within invaded urothelial cell in the form of biofilm-like intracellular bacterial communities and dispersal, leading to infection of next neighbouring cells. Therefore, the prevention and treatment of the urinary tract infections must include intracellular stage of infection.

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Clonal Structure, Virulence Factor-Encoding Genes and Antibiotic Resistance of Escherichia coli Causing Urinary Tract Infections and Other Extraintestinal Infections in Humans in Spain and France During 2016

10.20944/preprints202002.0463.v1 ◽

2020 ◽

Author(s):

Saskia-Camille Flament-Simon ◽

Marie-Hélène Nicolas-Chanoine ◽

Vanesa García ◽

Marion Duprilot ◽

Noémie Mayer ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Urinary Tract ◽

Virulence Factor ◽

Multidrug Resistant ◽

Clonal Structure ◽

E Coli ◽

Tract Infections ◽

Encoding Genes ◽

Sequence Types

Escherichia coli is the main pathogen responsible for extraintestinal infections. A total of 196 clinical E. coli consecutively isolated during 2016 in Spain (100 from Lucus Augusti hospital in Lugo) and France (96 from Beaujon hospital in Clichy) were characterized. Phylogroups, clonotypes, sequence types (STs), O:H serotypes, virulence factor (VF)-encoding genes and antibiotic resistance were determined. Approximately 10% of the infections were caused by ST131 isolates in both hospitals and approximately 60% of these infections were caused by isolates belonging to only 10 STs (ST10, ST12, ST58, ST69, ST73, ST88, ST95, ST127, ST131, ST141). ST88 isolates were frequent especially in Spain while ST141 isolates significantly predominated in France. The 23 ST131 isolates displayed four clonotypes: CH40-30, CH40-41, CH40-22 and CH40-298. Only 13 (6.6%) isolates were carriers of ESBL enzymes. However, 37.2% of the isolates were multidrug-resistant (MDR). Approximately 40% of the MDR isolates belonged to only four of the dominant clones (B2-CH40-30-ST131, B2-CH40-41-ST131, C-CH4-39-ST88 and D-CH35-27-ST69). Among the remaining MDR isolates two isolates belonged to B2-CH14-64-ST1193 i.e the new global emergent MDR clone. To our knowledge, it is the first identification of this emergent clone in Spain. Moreover, a hybrid ExPEC/enteroaggregative isolate belonging to A-CH11-54-ST10 clone was identified.

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Waterborne Urinary Tract Infections: Have We Overlooked an Important Source of Exposure?

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.20-1271 ◽

2021 ◽

Author(s):

Jay P. Graham ◽

Heather Amato ◽

Renata Mendizabal-Cabrera ◽

Danilo Alvarez ◽

Brooke Ramay

Keyword(s):

Escherichia Coli ◽

Drinking Water ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Scientific Literature ◽

Adult Women ◽

Water Supplies ◽

E Coli ◽

Tract Infections

The presence of intestinal pathogenic Escherichia coli in drinking water is well recognized as a risk for diarrhea. The role of drinking water in extraintestinal infections caused by E. coli—such as urinary tract infections (UTIs)—remains poorly understood. Urinary tract infections are a leading cause of outpatient infections globally, with a lifetime incidence of 50–60% in adult women. We reviewed the scientific literature on the occurrence of uropathogenic E. coli (UPEC) in water supplies to determine whether the waterborne route may be an important, overlooked, source of UPEC. A limited number of studies have assessed whether UPEC isolates are present in drinking water supplies, but no studies have measured whether their presence in water may increase UPEC colonization or the risk of UTIs in humans. Given the prevalence of drinking water supplies contaminated with E. coli across the globe, efforts should be made to characterize UTI-related risks associated with drinking water, as well as other pathways of exposure.

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Iron Acquisition of Urinary Tract Infection Escherichia coli Involves Pathogenicity in Caenorhabditis elegans

Microorganisms ◽

10.3390/microorganisms9020310 ◽

2021 ◽

Vol 9 (2) ◽

pp. 310

Author(s):

Masayuki Hashimoto ◽

Yi-Fen Ma ◽

Sin-Tian Wang ◽

Chang-Shi Chen ◽

Ching-Hao Teng

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Caenorhabditis Elegans ◽

Large Scale ◽

Iron Acquisition ◽

Infection Model ◽

High Throughput Analysis ◽

E Coli ◽

C Elegans ◽

Tract Infections

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.

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Characterization of Anti-Bacterial Effect of the Two New Phages against Uropathogenic Escherichia coli

Viruses ◽

10.3390/v13071348 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1348

Author(s):

Lívia Slobodníková ◽

Barbora Markusková ◽

Michal Kajsík ◽

Michal Andrezál ◽

Marek Straka ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Therapeutic Potential ◽

Medical Intervention ◽

Uropathogenic Escherichia Coli ◽

E Coli ◽

Phage Cocktail ◽

Causative Agents ◽

Tract Infections

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.

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Viability and survival capability of quinolone-resistant uropathogenic Escherichia coli

Open Life Sciences ◽

10.2478/s11535-010-0070-9 ◽

2010 ◽

Vol 5 (6) ◽

pp. 827-830

Author(s):

Georgi Slavchev ◽

Nadya Markova

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Expression System ◽

Antibiotic Sensitivity ◽

Uropathogenic Escherichia Coli ◽

Resistant Bacteria ◽

E Coli ◽

Serum Bactericidal Assay ◽

Tract Infections ◽

Macrophage Killing

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.

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Single Clinical Isolates from Acute Uncomplicated Urinary Tract Infections Are Representative of Dominant In Situ Populations

mBio ◽

10.1128/mbio.01064-13 ◽

2014 ◽

Vol 5 (2) ◽

Cited By ~ 18

Author(s):

Dana Willner ◽

Serene Low ◽

Jason A. Steen ◽

Narelle George ◽

Graeme R. Nimmo ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Clinical Isolates ◽

Content Type ◽

E Coli ◽

Strain Diversity ◽

Amplicon Pyrosequencing ◽

Culture Independent ◽

Tract Infections

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.

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Biological Cost of Single and Multiple Norfloxacin Resistance Mutations in Escherichia coli Implicated in Urinary Tract Infections

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.6.2343-2351.2005 ◽

2005 ◽

Vol 49 (6) ◽

pp. 2343-2351 ◽

Cited By ~ 91

Author(s):

Patricia Komp Lindgren ◽

Linda L. Marcusson ◽

Dorthe Sandvang ◽

Niels Frimodt-Møller ◽

Diarmaid Hughes

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Infection Model ◽

Resistance Mutations ◽

Topoisomerase Iv ◽

E Coli ◽

Tract Infections ◽

Subsequent Selection

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.

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