scholarly journals Flagella, Type I Fimbriae and Curli of Uropathogenic Escherichia coli Promote the Release of Proinflammatory Cytokines in a Coculture System

2021 ◽  
Vol 9 (11) ◽  
pp. 2233
Author(s):  
Rubí Vega-Hernández ◽  
Sara A. Ochoa ◽  
Ricardo Valle-Rios ◽  
Gustavo A. Jaimes-Ortega ◽  
José Arellano-Galindo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Proinflammatory Cytokines ◽  
Public Health Problem ◽  
Uropathogenic Escherichia Coli ◽  
Type I ◽  
Upec Strain ◽  
Coculture System ◽  
Type I Fimbriae ◽  
High Concentrations ◽  
Tract Infections

Background. Urinary tract infections (UTIs) are a public health problem in Mexico, and uropathogenic Escherichia coli (UPEC) is one of the main etiological agents. Flagella, type I fimbriae, and curli promote the ability of these bacteria to successfully colonize its host. Aim. This study aimed to determine whether flagella-, type I fimbriae-, and curli-expressing UPEC induces the release of proinflammatory cytokines in an established coculture system. Methods. The fliC, fimH, and csgA genes by UPEC strain were disrupted by allelic replacement. Flagella, type I fimbriae, and curli were visualized by transmission electron microscopy (TEM). HTB-5 (upper chamber) and HMC-1 (lower chamber) cells cocultured in Transwell® plates were infected with these UPEC strains and purified proteins. There was adherence to HTB-5 cells treated with different UPEC strains and they were quantified as colony-forming units (CFU)/mL. Results. High concentrations of IL-6 and IL-8 were induced by the FimH and FliC proteins; however, these cytokines were detected in low concentrations in presence of CsgA. Compared with UPEC CFT073, CFT073ΔfimH, CFT073ΔfimHΔfliC, and CFT073ΔcsgAΔfimH strains significantly reduced the adherence to HTB-5 cells. Conclusion. The FimH and FliC proteins are involved in IL-6 and IL-8 release in a coculture model of HTB-5 and HMC-1 cells.

scholarly journals Effective anti-adhesives of uropathogenic Escherichia coli

2018 ◽  
Vol 68 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Rosana Ribić ◽  
Tomislav Meštrović ◽  
Marijana Neuberg ◽  
Goran Kozina
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Antimicrobial Agents ◽  
Financial Burden ◽  
Uropathogenic Escherichia Coli ◽  
Host Cells ◽  
Type I ◽  
Development Of Resistance ◽  
Type I Fimbriae ◽  
Tract Infections

Abstract Urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) are among the most common infectious diseases in humans. Due to their frequent occurrence in the community and nosocomial settings, as well as the development of resistance to the commonly prescribed antimicrobial agents, an enormous financial burden is placed on healthcare systems around the world. Therefore, novel approaches to the prevention and treatment of UTIs are needed. Although UPEC may harbour a plethora of virulence factors, type I fimbriae and P pili are two of the most studied adhesive organelles, since the attachment to host cells in the urinary tract is a crucial step towards infection. Design of receptor analogues that competitively bind to UPEC surface adhesins placed at the top of pili organelles led to the development of anti-adhesive drugs that are increasingly recognized as important and promising alternatives to antibiotic treatment of UTIs.

scholarly journals D-Mannoside FimH Inhibitors as Non-Antibiotic Alternatives for Uropathogenic Escherichia coli

Antibiotics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1072
Author(s):  
Alfredo Montes-Robledo ◽  
Rosa Baldiris-Avila ◽  
Johan Fabian Galindo
Keyword(s):  
Escherichia Coli ◽  
3D Structure ◽  
Pcr Amplification ◽  
Uropathogenic Escherichia Coli ◽  
Crystallographic Structure ◽  
Type I ◽  
Dynamic Simulations ◽  
Lectin Domain ◽  
In Silico Studies ◽  
Tract Infections

FimH is a type I fimbria of uropathogenic Escherichia coli (UPEC), recognized for its ability to adhere and infect epithelial urinary tissue. Due to its role in the virulence of UPEC, several therapeutic strategies have focused on the study of FimH, including vaccines, mannosides, and molecules that inhibit their assembly. This work has focused on the ability of a set of monosubstituted and disubstituted phenyl mannosides to inhibit FimH. To determine the 3D structure of FimH for our in silico studies, we obtained fifteen sequences by PCR amplification of the fimH gene from 102 UPEC isolates. The fimH sequences in BLAST had a high homology (97–100%) to our UPEC fimH sequences. A search for the three-dimensional crystallographic structure of FimH proteins in the PDB server showed that proteins 4X5P and 4XO9 were found in 10 of the 15 isolates, presenting a 67% influx among our UPEC isolates. We focused on these two proteins to study the stability, free energy, and the interactions with different mannoside ligands. We found that the interactions with the residues of aspartic acid (ASP 54) and glutamine (GLN 133) were significant to the binding stability. The ligands assessed demonstrated high binding affinity and stability with the lectin domain of FimH proteins during the molecular dynamic simulations, based on MM-PBSA analysis. Therefore, our results suggest the potential utility of phenyl mannoside derivatives as FimH inhibitors to mitigate urinary tract infections produced by UPEC; thus, decreasing colonization, disease burden, and the costs of medical care.

scholarly journals Fur Represses Adhesion to, Invasion of, and Intracellular Bacterial Community Formation within Bladder Epithelial Cells and Motility in Uropathogenic Escherichia coli

2016 ◽  
Vol 84 (11) ◽  
pp. 3220-3231 ◽  
Author(s):  
Kumiko Kurabayashi ◽  
Tomohiro Agata ◽  
Hirofumi Asano ◽  
Haruyoshi Tomita ◽  
Hidetada Hirakawa
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cells ◽  
Antimicrobial Agents ◽  
Host Cells ◽  
Type I ◽  
Wild Type ◽  
Content Type ◽  
Type I Fimbriae ◽  
Tract Infections

Uropathogenic Escherichia coli (UPEC) is a major pathogen that causes urinary tract infections (UTIs). This bacterium adheres to and invades the host cells in the bladder, where it forms biofilm-like polymicrobial structures termed intracellular bacterial communities (IBCs) that protect UPEC from antimicrobial agents and the host immune systems. Using genetic screening, we found that deletion of the fur gene, which encodes an iron-binding transcriptional repressor for iron uptake systems, elevated the expression of type I fimbriae and motility when UPEC was grown under iron-rich conditions, and it led to an increased number of UPEC cells adhering to and internalized in bladder epithelial cells. Consequently, the IBC colonies that the fur mutant formed in host cells were denser and larger than those formed by the wild-type parent strain. Fur is inactivated under iron-restricted conditions. When iron was depleted from the bacterial cultures, wild-type UPEC adhesion, invasion, and motility increased, similar to the case with the fur mutant. The purified Fur protein bound to regions upstream of fimA and flhD , which encode type I fimbriae and an activator of flagellar expression that contributes to motility, respectively. These results suggest that Fur is a repressor of fimA and flhD and that its repression is abolished under iron-depleted conditions. Based on our in vitro experiments, we conclude that UPEC adhesion, invasion, IBC formation, and motility are suppressed by Fur under iron-rich conditions but derepressed under iron-restricted conditions, such as in patients with UTIs.

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

2005 ◽  
Vol 73 (11) ◽  
pp. 7644-7656 ◽  
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.

scholarly journals FNR Regulates Expression of Important Virulence Factors Contributing to Pathogenicity of Uropathogenic Escherichia coli

2014 ◽  
Vol 82 (12) ◽  
pp. 5086-5098 ◽  
Author(s):  
Nicolle L. Barbieri ◽  
Bryon Nicholson ◽  
Ashraf Hussein ◽  
Wentong Cai ◽  
Yvonne M. Wannemuehler ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Factors ◽  
Bacterial Infections ◽  
Uropathogenic Escherichia Coli ◽  
Type I ◽  
Wild Type ◽  
Global Regulator ◽  
Content Type ◽  
Tract Infections

ABSTRACTUropathogenicEscherichia coli(UPEC) is responsible for the majority of urinary tract infections (UTIs), which are some of the world's most common bacterial infections of humans. Here, we examined the role of FNR (fumarate andnitratereduction), a well-known global regulator, in the pathogenesis of UPEC infections. We constructed anfnrdeletion mutant of UPEC CFT073 and compared it to the wild type for changes in virulence, adherence, invasion, and expression of key virulence factors. Compared to the wild type, thefnrmutant was highly attenuated in the mouse model of human UTI and showed severe defects in adherence to and invasion of bladder and kidney epithelial cells. Our results showed that FNR regulates motility and multiple virulence factors, including expression of type I and P fimbriae, modulation of hemolysin expression, and expression of a novel pathogenicity island involved in α-ketoglutarate metabolism under anaerobic conditions. Our results demonstrate that FNR is a key global regulator of UPEC virulence and controls expression of important virulence factors that contribute to UPEC pathogenicity.

scholarly journals d-Mannose Treatment neither Affects Uropathogenic Escherichia coli Properties nor Induces Stable FimH Modifications

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 316 ◽  
Author(s):  
Daniela Scribano ◽  
Meysam Sarshar ◽  
Carla Prezioso ◽  
Marco Lucarelli ◽  
Antonio Angeloni ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Bacterial Growth ◽  
Good Alternative ◽  
Uropathogenic Escherichia Coli ◽  
Bacterial Metabolism ◽  
Upec Strain ◽  
Bladder Cell ◽  
Microbiological Methods ◽  
Strain Cft073 ◽  
Tract Infections

Urinary tract infections (UTIs) are mainly caused by uropathogenic Escherichia coli (UPEC). Acute and recurrent UTIs are commonly treated with antibiotics, the efficacy of which is limited by the emergence of antibiotic resistant strains. The natural sugar d-mannose is considered as an alternative to antibiotics due to its ability to mask the bacterial adhesin FimH, thereby preventing its binding to urothelial cells. Despite its extensive use, the possibility that d-mannose exerts “antibiotic-like” activity by altering bacterial growth and metabolism or selecting FimH variants has not been investigated yet. To this aim, main bacterial features of the prototype UPEC strain CFT073 treated with d-mannose were analyzed by standard microbiological methods. FimH functionality was analyzed by yeast agglutination and human bladder cell adhesion assays. Our results indicate that high d-mannose concentrations have no effect on bacterial growth and do not interfere with the activity of different antibiotics. d-mannose ranked as the least preferred carbon source to support bacterial metabolism and growth, in comparison with d-glucose, d-fructose, and l-arabinose. Since small glucose amounts are physiologically detectable in urine, we can conclude that the presence of d-mannose is irrelevant for bacterial metabolism. Moreover, d-mannose removal after long-term exposure did not alter FimH’s capacity to bind to mannosylated proteins. Overall, our data indicate that d-mannose is a good alternative in the prevention and treatment of UPEC-related UTIs.

Identification and Ranking of Clinical Compounds with Activity Against Log-phase Growing Uropathogenic Escherichia coli

2020 ◽  
Vol 17 (2) ◽  
pp. 191-196
Author(s):  
Hongxia Niu ◽  
Rebecca Yee ◽  
Peng Cui ◽  
Shuo Zhang ◽  
Lili Tian ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Uropathogenic Escherichia Coli ◽  
Protein Synthesis Inhibitor ◽  
Beta Lactam ◽  
Synthesis Inhibitor ◽  
Upec Strain ◽  
Antibiotic Resistant ◽  
Tetracycline Antibiotics ◽  
Cephalosporin Antibiotics ◽  
Tract Infections

Background: Uropathogenic Escherichia coli (UPEC) is a major cause of Urinary Tract Infections (UTIs). Due to increasing antibiotic-resistance among UPEC bacteria, new treatment options for UTIs are urgently needed. Objective: To identify new agents targeting growing bacteria that may be used for the treatment of antibiotic-resistant UTIs. Methods: We screened a clinical compound library consisting of 1,524 compounds using a high throughput 96-well plate assay and ranked the activities of the selected agents according to their MICs against the UPEC strain UTI89. Results: We identified 33 antibiotics which were active against log-phase clinical UPEC strain UTI89. Among the selected antibiotics, there were 12 fluoroquinolone antibiotics (tosufloxacin, levofloxacin, sparfloxacin, clinafloxacin, pazufloxacin, gatifloxacin, enrofloxacin, lomefloxacin, norfloxacin, fleroxacin, flumequine, ciprofloxacin), 15 beta-lactam or cephalosporin antibiotics (cefmenoxime, cefotaxime, ceftizoxime, cefotiam, cefdinir, cefoperazone, cefpiramide, cefamandole, cefixime, ceftibuten, cefmetazole, cephalosporin C, aztreonam, piperacillintazobactam, mezlocillin), 3 tetracycline antibiotics (meclocycline, doxycycline, tetracycline), 2 membrane-acting agents (colistin and clofoctol), and 1 protein synthesis inhibitor (amikacin). Among them, the top 7 hits were colistin, tosufloxacin, levofloxacin, sparfloxacin, clinafloxacin, cefmenoxime and pazufloxacin, where clinafloxacin and pazufloxacin were the newly identified agents active against UPEC strain UTI89. We validated the key results obtained with UTI89 on two other UTI strains CFT073 and KTE181 and found that they all had comparable MICs for fluoroquinolones while CFT073 and KTE181 were more susceptible to cephalosporin antibiotics and tetracycline antibiotics but were less susceptible to colistin than UTI89. Conclusion: Our findings provide possible effective drug candidates for the more effective treatment of antibiotic-resistant UTIs.

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

Viruses ◽  
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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