scholarly journals Abolition of Biofilm Formation in Urinary Tract Escherichia coli and Klebsiella Isolates by Metal Interference through Competition for Fur

2010 ◽  
Vol 76 (12) ◽  
pp. 3836-3841 ◽  
Author(s):  
Viktoria Hancock ◽  
Malin Dahl ◽  
Per Klemm
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Biofilm Formation ◽  
Iron Uptake ◽  
Regulatory System ◽  
Bacterial Biofilms ◽  
Divalent Metal Ions ◽  
Chronic Infections ◽  
E Coli ◽  
Microtiter Plates

ABSTRACT Bacterial biofilms are associated with a large number of persistent and chronic infections. Biofilm-dwelling bacteria are particularly resistant to antibiotics and immune defenses, which makes it hard if not impossible to eradicate biofilm-associated infections. In the urinary tract, free iron is strictly limited but is critical for bacterial growth. Biofilm-associated Escherichia coli cells are particularly desperate for iron. An attractive way of inhibiting biofilm formation is to fool the bacterial regulatory system for iron uptake. Here, we demonstrate that biofilm formation can be impaired by the addition of divalent metal ions, such as Zn(II) and Co(II), which inhibit iron uptake by virtue of their higher-than-iron affinity for the master controller protein of iron uptake, Fur. Reduced biofilm formation of urinary tract-infectious E. coli strains in the presence of Zn(II) was observed in microtiter plates and flow chambers as well as on urinary catheters. These results further support that iron uptake is indeed crucial for biofilm formation, and thereby, targeting these uptake systems might be an effective way to eradicate biofilms caused by infectious strains.

scholarly journals Effects of Trp- and Arg-Containing Antimicrobial-Peptide Structure on Inhibition of Escherichia coli Planktonic Growth and Biofilm Formation

2010 ◽  
Vol 76 (6) ◽  
pp. 1967-1974 ◽  
Author(s):  
Shuyu Hou ◽  
Zhigang Liu ◽  
Anne W. Young ◽  
Sheron L. Mark ◽  
Neville R. Kallenbach ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Surface Coverage ◽  
Antimicrobial Activities ◽  
Peptide Structure ◽  
High Morbidity ◽  
Chronic Infections ◽  
E Coli ◽  
Planktonic Growth ◽  
Biofilm Dispersion

ABSTRACT Biofilms are sessile microbial communities that cause serious chronic infections with high morbidity and mortality. In order to develop more effective approaches for biofilm control, a series of linear cationic antimicrobial peptides (AMPs) with various arginine (Arg or R) and tryptophan (Trp or W) repeats [(RW) n -NH2, where n = 2, 3, or 4] were rigorously compared to correlate their structures with antimicrobial activities affecting the planktonic growth and biofilm formation of Escherichia coli. The chain length of AMPs appears to be important for inhibition of bacterial planktonic growth, since the hexameric and octameric peptides significantly inhibited E. coli growth, while tetrameric peptide did not cause noticeable inhibition. In addition, all AMPs except the tetrameric peptide significantly reduced E. coli biofilm surface coverage and the viability of biofilm cells, when added at inoculation. In addition to inhibition of biofilm formation, significant killing of biofilm cells was observed after a 3-hour treatment of preformed biofilms with hexameric peptide. Interestingly, treatment with the octameric peptide caused significant biofilm dispersion without apparent killing of biofilm cells that remained on the surface; e.g., the surface coverage was reduced by 91.5 ± 3.5% by 200 μM octameric peptide. The detached biofilm cells, however, were effectively killed by this peptide. Overall, these results suggest that hexameric and octameric peptides are potent inhibitors of both bacterial planktonic growth and biofilm formation, while the octameric peptide can also disperse existing biofilms and kill the detached cells. These results are helpful for designing novel biofilm inhibitors and developing more effective therapeutic methods.

scholarly journals Poloxamer 338 Affects Cell Adhesion and Biofilm Formation in Escherichia coli: Potential Applications in the Management of Catheter-Associated Urinary Tract Infections

Pathogens ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 885
Author(s):  
Mariarita Stirpe ◽  
Benedetta Brugnoli ◽  
Gianfranco Donelli ◽  
Iolanda Francolini ◽  
Claudia Vuotto
Keyword(s):  
Escherichia Coli ◽  
Cell Adhesion ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Biofilm Formation ◽  
Attenuated Total Reflection ◽  
Water Contact ◽  
E Coli ◽  
Static Conditions ◽  
Tract Infections

Poloxamers are nontoxic, amphiphilic copolymers used in different formulations. Due to its surfactant properties, Poloxamer 338 (P388) is herein proposed as a strategy to avoid biofilm formation often causing recalcitrant catheter-associated urinary tract infections (CAUTI). The aim is to evaluate the ability of P388 coatings to affect the adhesion of Ec5FSL and Ec9FSL Escherichia coli strains on silicone urinary catheters. Attenuated total reflection infrared spectroscopy, atomic force microscopy, and static water contact angle measurement were employed to characterize the P388-coated silicone catheter in terms of amount of P388 layered, coating thickness, homogeneity, and hydrophilicity. In static conditions, the antifouling power of P388 was defined by comparing the E. coli cells adherent on a hydrophilic P388-adsorbed catheter segment with those on an uncoated one. A P388-coated catheter, having a homogeneous coverage of 35 nm in thickness, reduced of 0.83 log10 and 0.51 log10 the biofilm of Ec5FSL and Ec9FSL, respectively. In dynamic conditions, the percentage of cell adhesion on P388-adsorbed silicone channels was investigated by a microfluidic system, simulating the in vivo conditions of catheterized patients. As a result, both E. coli isolates were undetected. The strong and stable antifouling property against E. coli biofilm lead us to consider P388 as a promising anti-biofilm agent for CAUTIs control.

scholarly journals Global Gene Expression Profiling of Asymptomatic Bacteriuria Escherichia coli during Biofilm Growth in Human Urine

2006 ◽  
Vol 75 (2) ◽  
pp. 966-976 ◽  
Author(s):  
Viktoria Hancock ◽  
Per Klemm
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Expression Profile ◽  
Human Urine ◽  
Biofilm Formation ◽  
Expression Profiles ◽  
Asymptomatic Bacteriuria ◽  
Knockout Mutant ◽  
Biofilm Growth ◽  
E Coli

ABSTRACT Urinary tract infection (UTI) is an important health problem worldwide, with many millions of cases each year, and Escherichia coli is the most common organism causing UTI in humans. Also, E. coli is responsible for most infections in patients with chronic indwelling bladder catheter. The two asymptomatic bacteriuria (ABU) E. coli strains 83972 and VR50 are significantly better biofilm formers in their natural growth medium, human urine, than the two uropathogenic E. coli isolates CFT073 and 536. We used DNA microarrays to monitor the expression profile during biofilm growth in urine of the two ABU strains 83972 and VR50. Significant differences in expression levels were seen between the biofilm expression profiles of the two strains with the corresponding planktonic expression profiles in morpholinepropanesulfonic acid minimal laboratory medium and human urine; 417 and 355 genes were up- and down-regulated, respectively, during biofilm growth in urine of 83972 and VR50. Many genes involved in transcription and stress were up-regulated in biofilm-grown cells. The role in biofilm formation of four of the up-regulated genes, i.e., yceP, yqgA, ygiD, and aaeX, was investigated by creating single-knockout mutant versions of 83972 and VR50; all mutants showed reduced biofilm formation in urine by 18 to 43% compared with the wild type (P < 0.05). Also, the expression profile of strain 83972 in the human urinary tract partially overlaps with the biofilm expression profile.

scholarly journals Pathogenic potential in catheter associated Escherichia coli is associated with separable biofilm and virulence gene determinants

2021 ◽  
Author(s):  
Zongsen Zou ◽  
Robert Potter ◽  
William McCoy ◽  
George Katumba ◽  
Peter J. Mucha ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Biofilm Formation ◽  
Gene Networks ◽  
Bacterial Colonization ◽  
Asymptomatic Bacteriuria ◽  
Virulence Gene ◽  
Multidrug Resistant ◽  
Pathogenic Potential ◽  
E Coli

Urinary catheterization facilitates asymptomatic bacterial colonization of the urinary tract and increases the risk of urinary tract infection (UTI). Differentiating catheter-associated asymptomatic bacteriuria (CAASB) from catheter-associated UTI (CAUTI) can be challenging when the presence or origins of symptoms are unclear. To determine whether strain-specific Escherichia coli characteristics are associated with CAUTI, we compared genomic composition and experimental catheter biofilm production by urinary isolates from catheterized inpatients and rectal isolates from healthy volunteers. CAUTI isolates were associated with a distinctive phylotype B2 sub-clade dominated by the multidrug resistant, pandemic ST131 lineage. While catheter biofilm formation was widespread among E. coli isolates, phylotype B2 biofilms were more extensive and biofilm-associated genes were preferentially found in B2 and ST131 isolates. Distinctive suites of iron-responsive genes were associated with both the ST131 lineage and catheter biofilm formation. Catheter biofilms produced by some CAASB strains could inhibit ST131 colonization, suggesting a potential beneficial function for these strains. These results suggest that the combination of biofilm and non-biofilm-associated gene networks in urinary E. coli influence CAUTI risk in catheterized patients.

scholarly journals Evaluation of antimicrobial effects of Rosemary and Withania somnifera methanol extract prepared by ultrasound waveform on Escherichia coli biofilm isolated from urinary tract infection

2021 ◽  
Vol 1 (01) ◽  
pp. 17-25
Author(s):  
Maryam Beigomi ◽  
Asiyeh Biabangard ◽  
Reza Rohani
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract Infection ◽  
Urinary Tract ◽  
Tract Infection ◽  
Biofilm Formation ◽  
Withania Somnifera ◽  
Significance Level ◽  
Antimicrobial Effects ◽  
E Coli ◽  
Significant Difference

Generally, bacteria co-exist setting up communities associated to solid superficies, this is to which we refer as biofilms that serve as a survival strategy. This type of formation cause serious sanitary problems for both humans and animals. Nowadays, chemical or natural compounds able to block this formation are looked for. In this project, we have evaluation of antimicrobial effects of Rosemary and Withania somnifera extract prepared by ultrasound waveform on Escherichia coli biofilm isolated from urinary tract infection. Rosemary and Withania somnifera extracts were obtained by using rotary devices. E. coli was collected from the patients being cured in Zabol hospitals. The least hindering and killing concentration of the samples were calculated by lowering their densityin sinks. The growth and biofilm formation of strains were determined by microtiterplate method. Data were analyzed statistically by determination of significant difference using analysis of variance (ANOVA) test. All tests were analyzed at the significance level P less than 0.05. The results revealed that the concentrations of 5 and 10 mg/mL are the most restrain in the biofilm formation of the isolated plates. Rosemary and Withania somnifera extracts have considerable antimicrobial and ant biofilm effect on the samples of the E. coli resistant to antibiotics.

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.

scholarly journals Bacterial Profile of Urinary Tract Infections: Evaluation of Biofilm Formation and Antibiotic Resistance Pattern of Uropathogenic Escherichia coli

2020 ◽  
Vol 14 (4) ◽  
pp. 2577-2584
Author(s):  
Tariq Ahmad Shah ◽  
P. Preethishree ◽  
Ashwini ◽  
Vidya Pai
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Urinary Tract ◽  
Biofilm Formation ◽  
Urine Samples ◽  
Diffusion Method ◽  
E Coli ◽  
Biofilm Production ◽  
Tract Infections

Urinary tract infection (UTI) is one of the most common complaints in the outpatient clinic and a major health problem owing to the emergence of antibiotic resistance and biofilm formation. The objective of this study was to isolate and identify the causative bacterial agent of UTI and detect in vitro biofilm formation by Escherichia coli and investigate its correlation with antibiotic resistance. Urine samples from 519 patients with suspected UTIs were collected and processed by conventional microbiological procedures. Antimicrobial susceptibility testing for E. coli isolates was performed on Mueller Hinton agar (MHA) plates using the Kirby-Bauer disk diffusion method. Biofilm production was evaluated using the tissue culture plate method. Of 519 urine samples, 115 (22.1%) showed significant bacteriuria. The most common isolate was E. coli (n=57, 49.6%), followed by Klebsiella spp. (n=23, 20%). All E. coli isolates were evaluated for their ability to form biofilms in vitro. Of 57 isolates, 50 (87.7%) were biofilm producers and 7 (12.3%) were non-biofilm producers. Antibiogram of E. coli isolates revealed the highest resistance to ampicillin (96.5%) and nitrofurantoin (91.2%), followed by amoxyclav (82.5%), ceftazidime (73.7%), cefepime (71.9%), and tetracycline (71.9%). A significant association (p<0.05) was observed between biofilm formation and resistance to amoxyclav, ceftazidime, cefepime, imipenem, and nitrofurantoin. A significant correlation was noted between biofilm production and antibiotic resistance. Hence, screening of all isolates of uropathogenic E. coli for biofilm production and studying their antibiogram would allow appropriate choice of antibiotic therapy.

scholarly journals Efficacy of A Poly(MeOEGMA) Brush on the Prevention of Escherichia coli Biofilm Formation and Susceptibility

Antibiotics ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 216 ◽  
Author(s):  
Patrícia Alves ◽  
Luciana Calheiros Gomes ◽  
Cesar Rodríguez-Emmenegger ◽  
Filipe José Mergulhão
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Biofilm Formation ◽  
Polymer Brush ◽  
Cell Number ◽  
Flow Chamber ◽  
E Coli ◽  
Tract Infections ◽  
Hospital Acquired ◽  
Control Surfaces

Urinary tract infections are one of the most common hospital-acquired infections, and they are often associated with biofilm formation in indwelling medical devices such as catheters and stents. This study aims to investigate the antibiofilm performance of a polymer brush—poly[oligo(ethylene glycol) methyl ether methacrylate], poly(MeOEGMA)—and evaluate its effect on the antimicrobial susceptibility of Escherichia coli biofilms formed on that surface. Biofilms were formed in a parallel plate flow chamber (PPFC) for 24 h under the hydrodynamic conditions prevailing in urinary catheters and stents and challenged with ampicillin. Results obtained with the brush were compared to those obtained with two control surfaces, polydimethylsiloxane (PDMS) and glass. The polymer brush reduced by 57% the surface area covered by E. coli after 24 h, as well as the number of total adhered cells. The antibiotic treatment potentiated cell death and removal, and the total cell number was reduced by 88%. Biofilms adapted their architecture, and cell morphology changed to a more elongated form during that period. This work suggests that the poly(MeOEGMA) brush has potential to prevent bacterial adhesion in urinary tract devices like ureteral stents and catheters, as well as in eradicating biofilms developed in these biomedical devices.

scholarly journals Enzymatically Active and Inactive Phosphodiesterases and Diguanylate Cyclases Are Involved in Regulation of Motility or Sessility in Escherichia coli CFT073

mBio ◽  
2012 ◽  
Vol 3 (5) ◽  
Author(s):  
Rachel R. Spurbeck ◽  
Rebecca J. Tarrien ◽  
Harry L. T. Mobley
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Biofilm Formation ◽  
Second Messenger ◽  
Content Type ◽  
E Coli ◽  
Diguanylate Cyclases ◽  
Genes Encoding ◽  
K 12 ◽  
Messenger Molecule

ABSTRACTIntracellular concentration of cyclic diguanylate monophosphate (c-di-GMP), a second messenger molecule, is regulated in bacteria by diguanylate cyclases (DGCs) (synthesizing c-di-GMP) and phosphodiesterases (PDEs) (degrading c-di-GMP). c-di-GMP concentration ([c-di-GMP]) affects motility and sessility in a reciprocal fashion; high [c-di-GMP] typically inhibits motility and promotes sessility. A c-di-GMP sensor domain, PilZ, also regulates motility and sessility. UropathogenicEscherichia coliregulates these processes during infection; motility is necessary for ascending the urinary tract, while sessility is essential for colonization of anatomical sites. Here, we constructed and screened 32 mutants containing deletions of genes encoding each PDE (n= 11), DGC (n= 13), PilZ (n= 2), and both PDE and DGC (n= 6) domains for defects in motility, biofilm formation, and adherence for the prototypical pyelonephritis isolateE. coliCFT073. Three of 32 mutations affected motility, all of which were in genes encoding enzymatically inactive PDEs. Four PDEs, eight DGCs, four PDE/DGCs, and one PilZ regulated biofilm formation in a medium-specific manner. Adherence to bladder epithelial cells was regulated by [c-di-GMP]. Four PDEs, one DGC, and three PDE/DGCs repress adherence and four DGCs and one PDE/DGC stimulate adherence. Thus, specific effectors of [c-di-GMP] and catalytically inactive DGCs and PDEs regulate adherence and motility in uropathogenicE. coli.IMPORTANCEUropathogenicEscherichia coli(UPEC) contains several genes annotated as encoding enzymes that increase or decrease the abundance of the second messenger molecule, c-di-GMP. While this class of enzymes has been studied in anE. coliK-12 lab strain, these proteins have not been comprehensively examined in UPEC. UPEC utilizes both swimming motility and adherence to colonize and ascend the urinary tract; both of these processes are hypothesized to be regulated by the concentration of c-di-GMP. Here, for the first time, in a uropathogenic strain,E. coliCFT073, we have characterized mutants lacking each protein and demonstrated that the uropathogen has diverged fromE. coliK-12 to utilize these enzymes to regulate adherence and motility by distinct mechanisms.

scholarly journals Contribution of Siderophore Systems to Growth and Urinary Tract Colonization of Asymptomatic Bacteriuria Escherichia coli

2011 ◽  
Vol 80 (1) ◽  
pp. 333-344 ◽  
Author(s):  
Rebecca E. Watts ◽  
Makrina Totsika ◽  
Victoria L. Challinor ◽  
Amanda N. Mabbett ◽  
Glen C. Ulett ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Human Urine ◽  
Iron Uptake ◽  
Asymptomatic Bacteriuria ◽  
Content Type ◽  
E Coli ◽  
Siderophore Biosynthesis ◽  
Iron Deficient ◽  
Deficient Medium

ABSTRACTThe molecular mechanisms that define asymptomatic bacteriuria (ABU)Escherichia colicolonization of the human urinary tract remain to be properly elucidated. Here, we utilize ABUE. colistrain 83972 as a model to dissect the contribution of siderophores to iron acquisition, growth, fitness, and colonization of the urinary tract. We show thatE. coli83972 produces enterobactin, salmochelin, aerobactin, and yersiniabactin and examine the role of these systems using mutants defective in siderophore biosynthesis and uptake. Enterobactin and aerobactin contributed most to total siderophore activity and growth in defined iron-deficient medium. No siderophores were detected in an 83972 quadruple mutant deficient in all four siderophore biosynthesis pathways; this mutant did not grow in defined iron-deficient medium but grew in iron-limited pooled human urine due to iron uptake via the FecA ferric citrate receptor. In a mixed 1:1 growth assay with strain 83972, there was no fitness disadvantage of the 83972 quadruple biosynthetic mutant, demonstrating its capacity to act as a “cheater” and utilize siderophores produced by the wild-type strain for iron uptake. An 83972 enterobactin/salmochelin double receptor mutant was outcompeted by 83972 in human urine and the mouse urinary tract, indicating a role for catecholate receptors in urinary tract colonization.

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