scholarly journals Transcriptome of Uropathogenic Escherichia coli during Urinary Tract Infection

2004 ◽  
Vol 72 (11) ◽  
pp. 6373-6381 ◽  
Author(s):  
Jennifer A. Snyder ◽  
Brian J. Haugen ◽  
Eric L. Buckles ◽  
C. Virginia Lockatell ◽  
David E. Johnson ◽  
...  

ABSTRACT A uropathogenic Escherichia coli strain CFT073-specific DNA microarray that includes each open reading frame was used to analyze the transcriptome of CFT073 bacteria isolated directly from the urine of infected CBA/J mice. The in vivo expression profiles were compared to that of E. coli CFT073 grown statically to exponential phase in rich medium, revealing the strategies this pathogen uses in vivo for colonization, growth, and survival in the urinary tract environment. The most highly expressed genes overall in vivo encoded translational machinery, indicating that the bacteria were in a rapid growth state despite specific nutrient limitations. Expression of type 1 fimbriae, a virulence factor involved in adherence, was highly upregulated in vivo. Five iron acquisition systems were all highly upregulated during urinary tract infection, as were genes responsible for capsular polysaccharide and lipopolysaccharide synthesis, drug resistance, and microcin secretion. Surprisingly, other fimbrial genes, such as pap and foc/sfa, and genes involved in motility and chemotaxis were downregulated in vivo. E. coli CFT073 grown in human urine resulted in the upregulation of iron acquisition, capsule, and microcin secretion genes, thus partially mimicking growth in vivo. On the basis of gene expression levels, the urinary tract appears to be nitrogen and iron limiting, of high osmolarity, and of moderate oxygenation. This study represents the first assessment of any E. coli pathotype's transcriptome in vivo and provides specific insights into the mechanisms necessary for urinary tract pathogenesis.

Microbiology ◽  
2009 ◽  
Vol 155 (5) ◽  
pp. 1634-1644 ◽  
Author(s):  
Lixiang Zhao ◽  
Song Gao ◽  
Haixia Huan ◽  
Xiaojing Xu ◽  
Xiaoping Zhu ◽  
...  

Avian pathogenic Escherichia coli (APEC) and uropathogenic E. coli (UPEC) establish infections in extraintestinal habitats of different hosts. As the diversity, epidemiological sources and evolutionary origins of extraintestinal pathogenic E. coli (ExPEC) are so far only partially defined, in the present study,100 APEC isolates and 202 UPEC isolates were compared by their content of virulence genes and phylogenetic groups. The two groups showed substantial overlap in terms of their serogroups, phylogenetic groups and virulence genotypes, including their possession of certain genes associated with large transmissible plasmids of APEC. In a chicken challenge model, both UPEC U17 and APEC E058 had similar LD50, demonstrating that UPEC U17 had the potential to cause significant disease in poultry. To gain further information about the similarities between UPEC and APEC, the in vivo expression of 152 specific genes of UPEC U17 and APEC E058 in both a murine urinary tract infection (UTI) model and a chicken challenge model was compared with that of these strains grown statically to exponential phase in rich medium. It was found that in the same model (murine UTI or chicken challenge), various genes of UPEC U17 and APEC E058 showed a similar tendency of expression. Several iron-related genes were upregulated in the UTI model and/or chicken challenge model, indicating that iron acquisition is important for E. coli to survive in blood or the urinary tract. Based on these results, the potential for APEC to act as human UPEC or as a reservoir of virulence genes for UPEC should be considered. Further, this study compared the transcriptional profile of virulence genes among APEC and UPEC in vivo.


2003 ◽  
Vol 71 (6) ◽  
pp. 3088-3096 ◽  
Author(s):  
Peter Redford ◽  
Paula L. Roesch ◽  
Rodney A. Welch

ABSTRACT Extraintestinal Escherichia coli strains cause meningitis, sepsis, urinary tract infection, and other infections outside the bowel. We examined here extraintestinal E. coli strain CFT073 by differential fluorescence induction. Pools of CFT073 clones carrying a CFT073 genomic fragment library in a promoterless gfp vector were inoculated intraperitoneally into mice; bacteria were recovered by lavage 6 h later and then subjected to fluorescence-activated cell sorting. Eleven promoters were found to be active in the mouse but not in Luria-Bertani (LB) broth culture. Three are linked to genes for enterobactin, aerobactin, and yersiniabactin. Three others are linked to the metabolic genes metA, gltB, and sucA, and another was linked to iha, a possible adhesin. Three lie before open reading frames of unknown function. One promoter is associated with degS, an inner membrane protease. Mutants of the in vivo-induced loci were tested in competition with the wild type in mouse peritonitis. Of the mutants tested, only CFT073 degS was found to be attenuated in peritoneal and in urinary tract infection, with virulence restored by complementation. CFT073 degS shows growth similar to that of the wild type at 37°C but is impaired at 43°C or in 3% ethanol LB broth at 37°C. Compared to the wild type, the mutant shows similar serum survival, motility, hemolysis, erythrocyte agglutination, and tolerance to oxidative stress. It also has the same lipopolysaccharide appearance on a silver-stained gel. The basis for the virulence attenuation is unclear, but because DegS is needed for σE activity, our findings implicate σE and its regulon in E. coli extraintestinal pathogenesis.


Revista Fitos ◽  
2019 ◽  
Vol 13 (4) ◽  
pp. 278-288
Author(s):  
Mariê Scotegagna Chiavini ◽  
Jane Mary Lafayette Neves Gelinski ◽  
Claudriana Locatelli ◽  
Pâmela Aparecida da Costa ◽  
Vânia Aparecida Vicente

The antimicrobial potential of cranberry hydro alcoholic extracts (CrE) was evaluated against Escherichia coli isolated from women with urinary tract infection (UTI). CrE was diluted based on the percentage of proanthocyanidins (PACs) in extract powder for final concentrations: 1.26%; 2.52%; 3.35%, 5.03% and 10.06%. CrE antimicrobial potential was evaluated by disk and well diffusion assays, and by in vitro direct action against E. coli. Antibacterial action was observed for all performed tests: minimal inhibitory concentration (MIC) was 1.26% PACs per disk diffusion assay and 2.52% of PACs by well diffusion assay. The in vitro antimicrobial direct action against E. coli resulted 3.8 Log10 cycles reduction for a concentration of 5.03% of PACs. One of the isolates showed multi resistance to antibiotics. But it was also inhibited more than any of the antibiotic tested in well diffusion assay. Only for concentrations 1.26%, 2.52% and 3.45% the inhibition of Escherichia coli by cranberry extract was dose-dependent, i.e directly proportional to the concentration of PACs. The results indicate a inhibitory action high potential of CrE. However, more in vitro and in vivo analysis can be performed to fix which the best concentration of CrE capable of causing a real beneficial effect on UTI´s.


2006 ◽  
Vol 74 (6) ◽  
pp. 3427-3436 ◽  
Author(s):  
Simon Léveillé ◽  
Mélissa Caza ◽  
James R. Johnson ◽  
Connie Clabots ◽  
Mourad Sabri ◽  
...  

ABSTRACT Virulence factors of pathogenic Escherichia coli belonging to a recently emerged and disseminated clonal group associated with urinary tract infection (UTI), provisionally designated clonal group A (CGA), have not been experimentally investigated. We used a mouse model of ascending UTI with CGA member strain UCB34 in order to identify genes of CGA that contribute to UTI. iha was identified to be expressed by strain UCB34 in the mouse kidney using selective capture of transcribed sequences. iha from strain UCB34 demonstrated a siderophore receptor phenotype when cloned in a catecholate siderophore receptor-negative E. coli K-12 strain, as shown by growth promotion experiments and uptake of 55Fe complexed to enterobactin or its linear 2, 3-dihydroxybenzoylserine (DHBS) siderophore derivatives. Siderophore-mediated growth promotion by Iha was TonB dependent. Growth and iron uptake were more marked with linear DHBS derivatives than with purified enterobactin. The reported phenotype of adherence to epithelial cells conferred by expressing iha from a multicopy cloning vector in a poorly adherent E. coli K-12 host strain was confirmed to be specific to iha, in comparison with other siderophore receptor genes. iha expression was regulated by the ferric uptake regulator Fur and by iron availability, as shown by real-time reverse transcriptase PCR. In a competitive infection experiment using the mouse UTI model, wild-type strain UCB34 significantly outcompeted an isogenic iha null mutant. Iha thus represents a Fur-regulated catecholate siderophore receptor that, uniquely, exhibits an adherence-enhancing phenotype and is the first described urovirulence factor identified in a CGA strain.


2020 ◽  
Vol 17 (35) ◽  
pp. 621-627
Author(s):  
May Ali Hussien UMRAN ◽  
Sumaya Najim AL-KHATEEB

The bacterium Escherichia coli is one of the best free-living organisms studied in depth. It is a surprisingly diverse species, since some strains of E. coli live in the intestine of animals as harmless commensals, while other distinct genotypes, such as an enteropathogenic or enterohemorrhagic E. coli, for example, cause morbidity and death marked as human intestinal pathogens. The purpose of this study was to develop and validate a PCR assay for a known and suspected uropathogenic E. coli virulence factor (kpsMT) gene region to determine the distribution of the gene and its role in the development of clinical diseases of the urinary system. A total of 25 urine samples were collected from patients with urinary tract infection (UTI) at Azadi and Kirkuk hospitals in the city of Kirkuk, Iraq. Samples of both genders and different ages were collected from patients with suspected urinary tract infection according to the clinical manifestations and symptoms diagnosed by the examining physician. The samples were cultured and positive samples were subjected to the IMViC test to identify E. coli bacteria and subsequently identified using the Vitek 2 compact system. Among 25 samples, 24 (96%) showed positive results for bacterial cultural growth. Of these, 17 (68%) were identified as Escherichia coli. Of the total of 17 isolates, 14 from patients with mild urinary tract infection, and 3 from patients with Urosepsis. The kpsMT gene was present in 14 isolates (82.3%), including 11 (78.5%) isolates from patients with mild urinary tract infection, and 3 (100%) isolates from patients with Urosepsis. It was concluded that Escherichia coli is the most prevalent in urine tract infection samples. Due to the abundance of the kpsMT gene in uropathogenic Escherichia coli (UPEC), this gene plays an important role in developing UTI if it is not treated correctly and quickly; mild cases of UTI can turn into Urosepsis.


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.


2020 ◽  
Vol 75 (12) ◽  
pp. 3656-3664
Author(s):  
Rasmus Richelsen ◽  
Jesper Smit ◽  
Henrik Carl Schønheyder ◽  
Pavithra Laxsen Anru ◽  
Belen Gutiérrez-Gutiérrez ◽  
...  

Abstract Objectives To assess the impact of ESBL production on mortality and length of hospital stay (LOS) of community-onset infections due to Escherichia coli or Klebsiella pneumoniae. Methods A population-based cohort study including all adult patients hospitalized with a first-time community-onset E. coli or K. pneumoniae bacteraemia or urinary tract infection in the North Denmark Region between 2007 and 2017. For each bacterial agent, we computed 1 year Kaplan–Meier survival curves and cumulative incidence functions of LOS, and by use of Cox proportional hazard regression we computed HRs as estimates of 30 day and 1 year mortality rate ratios (MRRs) and LOS among patients with and without ESBL-producing infections. Results We included 24 518 cases (among 22350 unique patients), of whom 1018 (4.2%) were infected by an ESBL-producing bacterium. The 30 day cumulative mortality and adjusted MRR (aMRR) in patients with and without ESBL-producing isolates was as follows: E. coli bacteraemia (n = 3831), 15.8% versus 14.0%, aMRR = 1.01 (95% CI = 0.70–1.45); E. coli urinary tract infection (n = 17151), 9.5% versus 8.7%, aMRR = 0.97 (95% CI = 0.75–1.26); K. pneumoniae bacteraemia (n = 734), 0% versus 17.2%, aMRR = not applicable; and K. pneumoniae urinary tract infection (n = 2802), 13.8% versus 10.7%, aMRR = 1.13 (95% CI = 0.73–1.75). The 1 year aMRR remained roughly unchanged. ESBL-producing E. coli bacteraemia was associated with an increased LOS compared with non-ESBL production. Conclusions ESBL production was not associated with an increased short- or long-term mortality in community-onset infections due to E. coli or K. pneumoniae, yet ESBL-producing E. coli bacteraemia was associated with an increased LOS.


2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Sunayana Raya ◽  
Ankit Belbase ◽  
Laxmi Dhakal ◽  
Krishna Govinda Prajapati ◽  
Reena Baidya ◽  
...  

Background. Diabetic patients are more susceptible to urinary tract infection compared to nondiabetic patients, Escherichia coli being the most common uropathogen causing UTI. Unreasonable and incorrect antibiotic prescription for UTI in these patients may induce the development of antibiotic-resistant urinary pathogens resulting in delayed recovery and longer hospitalization. In addition to these, biofilm forming capacity of the pathogen may worsen the problem. The main aim of this cross-sectional study (conducted from March to September 2015) is to detect the biofilm forming capacity of UTI causing micro-organisms and compare the antibiotic resistance pattern of Escherichia coli, the most common cause of UTI, which will help the physician in choosing the best antibiotic. Method. Total of 1,099 clean-catch mid stream urine (CCMSU) was processed by standard microbiological technique; 182 were from the diabetic group and 917 nondiabetic. Following identification, all isolates were subjected to antibiotic susceptibility testing using modified Kirby-Bauer disc diffusion method. In-vitro biofilm forming capacity of the isolates were detected by Microtitre plate method. The data were analyzed using SPSS software 16. Result. Urinary tract infection was found to be significantly higher in diabetic patients (42.9%) compared to nondiabetic patients (17.4%) with Escherichia coli as the most common uropathogen in both diabetic and nondiabetic groups. Similarly, UTI was more common in elderly population (29.5%). Imipenem, nitrofurantoin and amikacin were found to be the most effective drug for uropathogenic E. coli in both diabetic and nondiabetic patients, whereas amoxicillin, ciprofloxacin, and cotrimoxazole were least effective. Of the total bacterial isolates, 43.3% showed positive results for in-vitro biofilm production by the Microtitre plate method. A significantly higher resistance rate was observed among biofilm producing E. coli for quinolones, cotrimoxazole, and third generation cephalosporin ceftriaxone. Most of the biofilm producers (79.5%) were found to be MDR (p-value 0.015). Conclusion. Elderly populations with diabetes are at a higher risk of UTI. Higher biofilm production and resistance to in-use antimicrobial agents in this study render its inefficacy for empirical treatment and point out the importance of biofilm screening to ensure the effective management of infection.


Sign in / Sign up

Export Citation Format

Share Document