Analysis of uropathogenic Escherichia coli biofilm formation under different growth conditions

2015 ◽  
Vol 62 (4) ◽  
pp. 765-771 ◽  
Author(s):  
Wioletta Adamus-Białek ◽  
Anna Kubiak ◽  
Grzegorz Czerwonka
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Growth Conditions ◽  
Uropathogenic Escherichia Coli

scholarly journals Uropathogenic Escherichia coli Biofilm-Forming Capabilities are not Predictable from Clinical Details or from Colonial Morphology

Diseases ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 11 ◽  
Author(s):  
Shane Whelan ◽  
Mary Claire O’Grady ◽  
Dan Corcoran ◽  
Karen Finn ◽  
Brigid Lucey
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Culture Medium ◽  
Recurrent Infection ◽  
Positive Control ◽  
Uropathogenic Escherichia Coli ◽  
E Coli ◽  
Recurrent Uti ◽  
Colonial Morphology ◽  
The Difference

Antibiotic resistance is increasing to an extent where efficacy is not guaranteed when treating infection. Biofilm formation has been shown to complicate treatment, whereby the formation of biofilm is associated with higher minimum inhibitory concentration values of antibiotic. The objective of the current paper was to determine whether biofilm formation is variable among uropathogenic Escherichia coli isolates and whether formation is associated with recurrent urinary tract infection (UTI), and whether it can be predicted by phenotypic appearance on culture medium A total of 62 E. coli isolates that were reported as the causative agent of UTI were studied (33 from patients denoted as having recurrent UTI and 29 from patients not specified as having recurrent UTI). The biofilm forming capability was determined using a standard microtitre plate method, using E. coli ATCC 25922 as the positive control. The majority of isolates (93.6%) were found to be biofilm formers, whereby 81% were denoted as strong or very strong producers of biofilm when compared to the positive control. Through the use of a Wilcox test, the difference in biofilm forming propensity between the two patient populations was found to not be statistically significant (p = 0.5). Furthermore, it was noted that colony morphology was not a reliable predictor of biofilm-forming propensity. The findings of this study indicate that biofilm formation is very common among uropathogens, and they suggest that the biofilm-forming capability might be considered when treating UTI. Clinical details indicating a recurrent infection were not predictors of biofilm formation.

scholarly journals Distribution of genes encoding adhesins and biofilm formation capacity among Uropathogenic Escherichia coli isolates in relation to the antimicrobial resistance

2020 ◽  
Vol 20 (1) ◽  
pp. 238-247
Author(s):  
Ashraf A Kadry ◽  
Nour M Al-Kashef ◽  
Amira M El-Ganiny
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Antimicrobial Resistance ◽  
Biofilm Formation ◽  
Critical Role ◽  
Uropathogenic Escherichia Coli ◽  
Diffusion Method ◽  
Esbl Production ◽  
Microtitre Plate Assay ◽  
Genes Encoding

Background: Escherichia coli is the most predominant pathogen involved in UTIs. Mainly, fimbrial surface appendages are impli- cated in adherence to urothelium besides non-fimbrial proteins. Objectives: To determine prevalence of genes encoding fimbrial and non-fimbrial proteins among Uropathogenic Escherichia coli (UPEC). Furthermore, distribution of these genes and biofilm formation capacity were investigated in relation to antimicrobial resistance. Methods: Antimicrobial susceptibility of 112 UPEC isolates was performed using disc diffusion method. ESBL production was confirmed by double disc synergy test. Genes encoding fimbrial and non-fimbrial proteins were detected using PCR and biofilm formation was investigated using microtitre plate assay. Results: UPEC isolates exhibited high resistance against doxycyclines (88.39 %), β-lactams (7.14-86.6%), sulphamethoxaz- ole–trimethoprim (53.75%) and fluoro-quinolones (50%). Fifty percent of tested isolates were ESBL producers. PapGII gene was statistically more prevalent among pyelonephritis isolates. SfaS, focG and picU genes were statistically associated with flu- oro-quinolone (FQs) sensitive isolates and Dr/afaBC gene was statistically associated with ESBL production. Moreover, non- MDR isolates produced sturdier biofilm. Conclusion: PapGII adhesin variant seems to have a critical role in colonization of upper urinary tract. There is a possible link between antimicrobial resistance and virulence being capable of affecting the distribution of some genes besides its negative impact on biofilm formation. Keywords: Urinary tract infection; Escherichia coli; UPEC; adhesin genes; ESBL; biofilm.  

scholarly journals Evaluation of Biofilm Formation and Virulence Genes and Association with Antibiotic Resistance Patterns of Uropathogenic Escherichia coli Strains in Southwestern Iran

2021 ◽  
Vol 14 (9) ◽  
Author(s):  
Mostafa Boroumand ◽  
Asghar Sharifi ◽  
Mohammad Amin Ghatei ◽  
Mohsen Sadrinasab
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Urinary Tract ◽  
Biofilm Formation ◽  
Virulence Genes ◽  
Uropathogenic Escherichia Coli ◽  
E Coli ◽  
Resistance Patterns ◽  
Pcr Method ◽  
Antibiotic Resistance Patterns

Background: Uropathogenic Escherichia coli (UPEC) strains, encoding superficial and secretory virulence factors, can lead to colonization and facilitation of bacterial growth in the host urinary tract, causing Urinary Tract Infection (UTI). Objectives: This study determined the ability of biofilm formation by the Congo red agar (CRA) method, the presence of virulence genes using the multiplex polymerase chain reaction (PCR) method, and the relationship between biofilm formation and antibiotic resistance patterns and virulence genes in E. coli clinical isolates in Yasuj. Methods: This cross-sectional study was performed on 144 UPEC isolates collected in 2017. Biofilm formation was detected by the CRA phenotypic assay and virulence factors by the multiplex PCR method. Antibiotic resistance tests were performed by the Kirby-Bauer method. Results: Out of 144 isolates of E. coli, 22 (19.4%) isolates showed to be strong biofilm producers, 27 (23.8%) moderate biofilm producers, and 64 (56.3%) weak biofilm producers. A significant relationship was observed between biofilm-producing strains and resistance to ampicillin (P = 0.020) and cotrimoxazole (P = 0.038). The virulence genes in strong biofilm producers included iutA (95%), FimH (93%), ompT (90%), PAI (90%), and TraT (81%) genes. The phylogroup B2 carried the most virulence genes. A significant correlation was observed between E. coli phylogenetic groups and aer (P = 0.019), iroN (P = 0.042), and ompT (P = 0.032) virulence genes. Conclusions: The results of this study showed a high prevalence of virulence genes, and antibiotic-resistant E. coli strains capable of biofilm formation. The results of this study may help elucidate the pathogenesis of UPEC and facilitate better treatment strategies for patients with UTIs in this geographic area.

NoteThe stringent response genes relA and spoT are important for Escherichia coli biofilms under slow-growth conditions

2002 ◽  
Vol 48 (7) ◽  
pp. 675-680 ◽  
Author(s):  
Grant J Balzer ◽  
Robert J.C McLean
Keyword(s):  
Escherichia Coli ◽  
Cell Density ◽  
Biofilm Formation ◽  
Doubling Time ◽  
Stringent Response ◽  
Growth Conditions ◽  
Luria Bertani ◽  
Confocal Laser ◽  
Wild Type ◽  
Microtiter Plate Assay

In order to see whether the stringent response was involved in biofilm formation, Escherichia coli DS291 (MG1655), and its isogenic relA spoT derivative were grown for 48 h in a chemostat at dilution rates of 0.025 and 0.25 h–1 under serine limitation. The absence of the stringent response genes relA and spoT had little effect on the planktonic cell concentrations. However, a significant (P < 0.001) reduction in biofilm cell density of the relA spoT mutants was seen at a doubling time of 40 h. At a doubling time of 4 h, differences in biofilm cell density were not significant. Scanning confocal laser microscopy demonstrated the cell densities of microcolonies in the relA spoT mutant to be lower than those in the wild type. Using a microtiter plate assay, we found biofilm formation in relA spoT mutants to be similarly reduced in minimal media but to be enhanced in rich media (Luria–Bertani broth). No significant differences in biofilm formation were observed between wild type and isogenic relA mutants under any growth conditions. Overall, these results suggest that both stringent response genes relA and spoT are important in nutrient-limited biofilms. Key words: biofilm, stringent response, nutrient limitation, microcolony, Escherichia coli.

Disperse red 15 (DR15) impedes biofilm formation of uropathogenic Escherichia coli

2020 ◽  
Vol 138 ◽  
pp. 103772 ◽  
Author(s):  
Sandeep Miryala ◽  
Himesh Makala ◽  
Siva Prasad Yadavali ◽  
Ulaganathan Venkatasubramanian ◽  
Nagarajan Subbaiah ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Uropathogenic Escherichia Coli
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