scholarly journals Silver decorated myconanoparticles control growth and biofilm formation in uropathogenic E. coli

2021 ◽  
Author(s):  
Ranjani S ◽  
U. Rubiya Kathun U ◽  
S Hemalatha
Keyword(s):  
Endophytic Fungi ◽  
Biofilm Formation ◽  
Its Region ◽  
Alternative Source ◽  
Antibiotic Resistant ◽  
Synthesis Of Nanoparticles ◽  
E Coli ◽  
Vis Spectroscopy ◽  
Penicillium Sclerotiorum

Abstract Nanotechnology involves the synthesis of nanoparticles that has been used in therapeutic application for treating diseases. In this present study we have adopted the synthesis of myconanoparticles from the extracellular extract of endophytic fungi Penicillium sclerotiorum (PsNps) and validated for its antibacterial potential against antibiotic resistant uropathogenic E. coli and ATCC (25922) strain of E. coli. Endophytic fungi were isolated from the healthy leaves of Tamarindus indica. The genomic DNA from endophytic fungi was isolated and ITS region was amplified by polymerase chain reaction (PCR) using universal fungal primers ITS1 and ITS4and sequenced for the identification of endophytic fungal isolates. Penicillium sclerotiorum extract were used for the synthesis silver nanoparticles (PsNps) and were characterized by UV-Vis spectroscopy, Fourier transform- infrared spectroscopy (FTIR), Zeta potential, FE-SEM and Energy- Dispersive X-ray analysis (EDAX). Antibacterial activity of PsNps was tested against the antibiotic resistant uropathogenic E. coli and ATCC (25922) strain of E. coli. Further experiments were carried out to explore the potential of PsNps in regulating the CTX-M-15 gene. The antimicrobial activity showed that the PsNps inhibited growth, biofilm formation in both the strains of E. coli. The expression of gene encoding CTX-M-15 was down regulated in resistant strain of uropathogenic E. coli. Our results suggest that the PsNps could be used as an alternative source for the antibiotics. Thus, further studies can be conducted to prove the in vivo potential of PsNps and can be formulated for commercialization.

Punica granatum peel extracts mediated the green synthesis of gold nanoparticles and their detailed in vivo biological activities

2021 ◽  
Vol 10 (1) ◽  
pp. 882-892
Author(s):  
Sami Bawazeer ◽  
Abdur Rauf ◽  
Taufiq Nawaz ◽  
Anees Ahmed Khalil ◽  
Muhammad Sameem Javed ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Muscle Relaxant ◽  
Biological Activities ◽  
Punica Granatum ◽  
Environmental Safety ◽  
Surface Plasma Resonance ◽  
Pomegranate Peel ◽  
Synthesis Of Nanoparticles ◽  
Vis Spectroscopy

Abstract Requirements for developing new methodologies to biosynthesize nanoparticles are increasing day by day. The typical chemical synthesis of nanoparticles has raised concerns regarding environmental safety and adverse impact on human health. Therefore, there is an urgent need to develop green synthesized nanoparticles that are considered to be safe, ecofriendly, and cost-effective as compared to chemical approaches. Hence, in this study, we synthesized and characterized pomegranate peel extract-based gold nanoparticles (PP-AuNPs) through UV-visible spectroscopy, FT-IR, and AFM microscopy. Furthermore, the biological activities like analgesic, muscle relaxant, and sedative properties of synthesized PP-AuNPs were also determined. The change of color to dark ruby indicates the formation of AuNPs. The surface plasma resonance (SPR) peak in the absorption spectra was shown at 525 nm by using (UV-Vis) spectroscopy. A single distinctive peak implied the shape of nanoparticles to be spherical. AFM images revealed that the biosynthesized nanoparticles were spherical in shape. Furthermore, the images confirm the uniform distribution of PP-AuNPs with particle sizes ranging from 4 to 16 nm. Different classes of phytochemicals were preliminarily identified in extracts. The analgesic effect of extracts (70.04%) and PP-AuNPs (81.98%) demonstrated a significant (p < 0.001) percent reduction in writhing at a dose of 100 and 15 mg·kg−1, respectively. A mild muscle relaxant effect was noted against both the tested samples while a significant sedative effect was observed for both samples; however, PP-AuNPs weres more sedative compared to the extract. Pomegranate peel extracts and synthesized PP-AuNPs were found to possess significant analgesic, muscle relaxant, and sedative properties.

scholarly journals Effects ofibeADeletion on Virulence and Biofilm Formation of Avian PathogenicEscherichia coli

2010 ◽  
Vol 79 (1) ◽  
pp. 279-287 ◽  
Author(s):  
Shaohui Wang ◽  
Chunling Niu ◽  
Zhenyu Shi ◽  
Yongjie Xia ◽  
Muhammad Yaqoob ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Wild Type Strain ◽  
Chicken Embryo Fibroblast ◽  
Neonatal Meningitis ◽  
Pcr Analysis ◽  
E Coli ◽  
Reverse Transcription Pcr ◽  
Animal System ◽  
The Brain

ABSTRACTTheibeAgene is located on a genomic island, GimA, which is involved in the pathogenesis of neonatal meningitisEscherichia coli(NMEC) and avian pathogenicE. coli(APEC). The prevalence ofibeAin the APEC collection in China was investigated, and 20 of 467 strains (4.3%) were positive. In addition, analysis of the association of theE. colireference (ECOR) groups with positive strains revealed thatibeAwas linked to group B2. TheibeAgene in DE205B was analyzed and compared to those of APEC and NMEC, which indicated that the specificity ofibeAwas not consistent along pathotypes. The invasion of chicken embryo fibroblast DF-1 cells by APEC DE205B and RS218 was observed, which suggested that DF-1 cells could be a model to study the mechanism of APEC invasion. The inactivation ofibeAin APEC DE205B led to the reduced capacity to invade DF-1 cells, defective virulencein vivo, and decreased biofilm formation compared to the wild-type strain. In addition, strain AAEC189 expressingibeAexhibited enhanced invasion capacity and biofilm formation. The results of the quantitative real-time reverse transcription-PCR (qRT-PCR) analysis and animal system infection experiments indicated that the loss ofibeAdecreased the colonization and proliferation capacities of APEC in the brain during system infection.

scholarly journals Sensitivity of antibiotic resistant and antibiotic susceptible Escherichia coli, Enterococcus and Staphylococcus strains against ozone

2015 ◽  
Vol 13 (4) ◽  
pp. 1020-1028 ◽  
Author(s):  
Stefanie Heß ◽  
Claudia Gallert
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Resistance Pattern ◽  
Resistant Bacteria ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Enterococcus Casseliflavus ◽  
Subsurface Layers ◽  
Wastewater Samples ◽  
And Staphylococcus Aureus

Tolerance of antibiotic susceptible and antibiotic resistant Escherichia coli, Enterococcus and Staphylococcus strains from clinical and wastewater samples against ozone was tested to investigate if ozone, a strong oxidant applied for advanced wastewater treatment, will affect the release of antibiotic resistant bacteria into the aquatic environment. For this purpose, the resistance pattern against antibiotics of the mentioned isolates and their survival after exposure to 4 mg/L ozone was determined. Antibiotic resistance (AR) of the isolates was not correlating with higher tolerance against ozone. Except for ampicillin resistant E. coli strains, which showed a trend towards increased resistance, E. coli strains that were also resistant against cotrimoxazol, ciprofloxacin or a combination of the three antibiotics were similarly or less resistant against ozone than antibiotic sensitive strains. Pigment-producing Enterococcus casseliflavus and Staphylococcus aureus seemed to be more resistant against ozone than non-pigmented species of these genera. Furthermore, aggregation or biofilm formation apparently protected bacteria in subsurface layers from inactivation by ozone. The relatively large variance of tolerance against ozone may indicate that resistance to ozone inactivation most probably depends on several factors, where AR, if at all, does not play a major role.

scholarly journals An Overview of Biological and Computational Methods for Designing Mechanism-Informed Anti-biofilm Agents

2021 ◽  
Vol 12 ◽  
Author(s):  
Andy Y. An ◽  
Ka-Yee Grace Choi ◽  
Arjun S. Baghela ◽  
Robert E. W. Hancock
Keyword(s):  
Antibiotic Resistance ◽  
Small Molecules ◽  
In Silico ◽  
Biofilm Formation ◽  
Stringent Response ◽  
Antibiotic Resistant ◽  
Biologically Relevant ◽  
Biofilm Model

Bacterial biofilms are complex and highly antibiotic-resistant aggregates of microbes that form on surfaces in the environment and body including medical devices. They are key contributors to the growing antibiotic resistance crisis and account for two-thirds of all infections. Thus, there is a critical need to develop anti-biofilm specific therapeutics. Here we discuss mechanisms of biofilm formation, current anti-biofilm agents, and strategies for developing, discovering, and testing new anti-biofilm agents. Biofilm formation involves many factors and is broadly regulated by the stringent response, quorum sensing, and c-di-GMP signaling, processes that have been targeted by anti-biofilm agents. Developing new anti-biofilm agents requires a comprehensive systems-level understanding of these mechanisms, as well as the discovery of new mechanisms. This can be accomplished through omics approaches such as transcriptomics, metabolomics, and proteomics, which can also be integrated to better understand biofilm biology. Guided by mechanistic understanding, in silico techniques such as virtual screening and machine learning can discover small molecules that can inhibit key biofilm regulators. To increase the likelihood that these candidate agents selected from in silico approaches are efficacious in humans, they must be tested in biologically relevant biofilm models. We discuss the benefits and drawbacks of in vitro and in vivo biofilm models and highlight organoids as a new biofilm model. This review offers a comprehensive guide of current and future biological and computational approaches of anti-biofilm therapeutic discovery for investigators to utilize to combat the antibiotic resistance crisis.

Role of theehxAgene fromEscherichia coliserotype O82 in hemolysis, biofilm formation, and in vivo virulence

2015 ◽  
Vol 61 (5) ◽  
pp. 335-341 ◽  
Author(s):  
Chenggang Jiang ◽  
Tongqing An ◽  
Shujie Wang ◽  
Gang Wang ◽  
Wei Si ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Gastrointestinal Disease ◽  
Enterohemorrhagic Escherichia Coli ◽  
Systemic Complications ◽  
E Coli ◽  
Recombination System ◽  
Intestinal Pathology ◽  
Inflammatory Infiltrates

Enterohemorrhagic Escherichia coli (EHEC) strains cause serious gastrointestinal disease, which can lead to potentially life-threatening systemic complications such as hemolytic uremic syndrome. Although the ehx gene is established as a major virulence factor of EHEC, the role of this gene in colonization and biofilm formation remains to be elucidated. We constructed recombinant isogenic mutants of the ehxA locus of E. coli HLJ1122 (serotype O82) using the λ Red homologous recombination system. Significantly higher levels of adherence to human epithelial cells (HEp-2) cells were observed for strain HLJ1122 compared with the mutant strain HLJ1122-ΔehxA (P < 0.05). Strain HLJ1122 also exhibited significantly higher levels of biofilm formation than strain HLJ1122-ΔehxA (P < 0.05). Mice infected with strain HLJ1122 showed severe destruction of the intestinal and gastric mucosa; in contrast, mice infected with HLJ1122-ΔehxA showed limited intestinal pathology, displaying minimal inflammatory infiltrates compared with mock-infected mice. These results showed the multifunctional role of Ehx in E. coli virulence.

Phosphodiesterase activity of NbdA from Pseudomonas aeruginosa

2020 ◽  
Author(s):  
Anna Scherhag ◽  
Martina Rüger ◽  
Katrin Gerbracht ◽  
Jaqueline Rehner ◽  
Susanne Zehner ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Model Organism ◽  
Functional Complementation ◽  
Full Length ◽  
Protein Activity ◽  
E Coli ◽  
Diguanylate Cyclases ◽  
Ggdef Domain

&lt;p&gt;The molecule c-di-GMP is a bacterial second messenger that controls various processes such as motility or biofilm formation in bacteria [1]. To synthesize and degrade c-di-GMP, enzymes called diguanylate cyclases (DGC) containing a GGDEF-domain and phosphodiesterases (PDE) containing an EAL-domain or HD-GYP-domain are important [1, 2].&lt;em&gt; Pseudomonas aeruginosa&lt;/em&gt;, a model organism for biofilm formation and dispersion, encodes for 18 GGDEF, 5 EAL, 16 GGDEF / EAL, and 3 HD-GYP-domain-containing proteins [3].&lt;br /&gt;One of the GGDEF / EAL-containing proteins is NbdA. This protein also harbors an N-terminal membrane anchored MHYT-domain, that is predicted to be a sensor for NO, CO or O&lt;sub&gt;2&lt;/sub&gt; [4]. In this work, recombinant and affinity purified NbdA was tested for its PDE activity. Three different methods were used to measure the PDE activity of NbdA: a bis-pNPP-assay in which the conversion of the pseudosubstrate bis-pNPP into p-nitrophenol was detected spectroscopically, an HPLC-analysis of an enzymatic assay with the native substrate c-di-GMP, and a MANT-c-di-GMP-assay in which a fluorescently labeled form of the presumed substrate c-di-GMP was utilized.&lt;br /&gt;To establish these methods, the two known phosphodiesterases, PdeH from &lt;em&gt;Escherichia coli&lt;/em&gt; [5] and RocR from &lt;em&gt;P. aeruginosa&lt;/em&gt; [6], were also produced and tested. Subsequently, three variants of NbdA were investigated: the full-length version and two truncated versions of the protein. Activity was further assessed using functional complementation of an &lt;em&gt;E. coli&lt;/em&gt; phosphodiesterase deficient strain with full-length and truncated NbdA variants confirming PDE activity &lt;em&gt;in vivo&lt;/em&gt;.&lt;/p&gt; &lt;p&gt;&amp;#160;&lt;/p&gt; &lt;p&gt;&amp;#160;&lt;/p&gt; &lt;p&gt;[1] Hengge, R. (2009) Nature Rev. Microbiol. 7: 263-273.&lt;/p&gt; &lt;p&gt;[2] R&amp;#246;mling, U., Gomelsky, M., Galperin, M.Y. (2005). Mol. Microbiol. 57: 629&amp;#8211;639.&lt;/p&gt; &lt;p&gt;[3] Valentini, M., Filloux, A. (2016). J. Biol. Chem. 291: 12547&amp;#8211;12555.&lt;/p&gt; &lt;p&gt;[4] Galperin, M.Y., Gaidenko, T.A., Mulkidjanian, A.Y., Nakano, M., und Price, C.W. (2001). FEMS Microbiol. Lett. 205, 17&amp;#8211;23.&lt;/p&gt; &lt;p&gt;[5] Pesavento, C., Becker, G., Sommerfeldt, N., Possling, A., Tschowri, N., Mehlis, A., Hengge, R. (2008). Genes Dev. 22: 2434&amp;#8211;2446.&lt;/p&gt; &lt;p&gt;[6] Chen et al. (2012) Chen, M.W., Kotaka, M., Vonrhein, C., Bricogne, G., Rao, F., Chuah, M.L.C., Svergun, D., Schneider, G., Liang, Z.-X., Lescar, J.&amp;#160; (2012). Signaling. J. Bacteriol. 194: 4837&amp;#8211;4846&lt;/p&gt; &lt;p&gt;&amp;#160;&lt;/p&gt;

scholarly journals Actividad antibacteriana de extractos vegetales frente a cepas intrahospitalarias, Iquitos-Perú

2018 ◽  
pp. 31-38
Keyword(s):  
Antibacterial Activity ◽  
Plant Extracts ◽  
Diffusion Method ◽  
Cedrela Odorata ◽  
Annona Muricata ◽  
Antibiotic Resistant ◽  
Averrhoa Carambola ◽  
E Coli

Actividad antibacteriana de extractos vegetales frente a cepas intrahospitalarias, Iquitos-Perú Antibacterial activity of plant extracts against nosocomial strains, Iquitos-Peru Ricardo E. Abadie, Ronald Medina O., Lastenia Ruiz, Alvaro Tresierra-Ayala Laboratorio de Microbiología. Centro de Investigación de Recursos Naturales de la Universidad Nacional de la Amazonía Peruana (CIRNA-UNAP). Psje. Los Paujiles S/N, San Lorenzo, distrito de San Juan Bautista, Iquitos-Perú DOI: https://doi.org/10.33017/RevECIPeru2014.0005/  Resumen La región amazónica es una de las áreas que posee la mayor biodiversidad del mundo, albergando varios miles de especies de plantas, muchas de las cuales son utilizadas por sus pobladores como plantas medicinales. Durante los últimos años, el empleo de estos recursos vegetales o de sus productos viene incrementándose de manera importante, lo cual podría deberse a una serie de factores, entre los que destacan el conocimiento de su composición química, y al hecho que en la actualidad se han realizado numerosos ensayos farmacológicos tanto in vivo como in vitro. La aparición de cepas resistentes a los antibióticos comerciales en los últimos tiempos, está creando la necesidad de buscar otras estrategias o alternativas para controlarlas, tal es el caso del uso de las plantas (medicina tradicional), debido a los principios activos que poseen. Se pretende con este trabajo, determinar probables alternativas para combatir infecciones bacterianas de aquellos agentes drogoresistentes, este problema reviste importancia crítica particular en los países en desarrollo, donde quizás no se dispone de antibióticos de segunda línea más costosos o, si los hay, su precio es inasequible. El estudio se realizó en la ciudad de Iquitos, Provincia de Maynas, Departamento de Loreto. Los ensayos microbiológicos se realizaron en el Laboratorio de Microbiología del Centro de Investigación de Recursos Naturales de la Amazonia (CIRNA) de la Universidad Nacional de la Amazonia  Peruana (UNAP). Se determinó la actividad antibacteriana de 6 extractos vegetales (Alchornea triplinervia, Annona muricata, Averrhoa carambola, Brunfelsia grandiflora, Caraipa grandifolia y Cedrela odorata) mediante la técnica de difusión en disco, y a aquellos que presentaron actividad se les determinó la Concentración Inhibitoria Mínima y la Concentración Bactericida Mínima mediante la técnica de macrodilución en caldo. Ninguno de los extractos tuvieron actividad frente a las cepas de E. coli; cuatro extractos tuvieron actividad frente a las cepas de P. aeruginosa, siendo los extractos de Cedrela odorata y Alchornea triplinervia los que tuvieron mayor actividad frente a esta bacteria, con CIM = 15.62 y 62.5 mg/ml, respectivamente; todos los extractos tuvieron actividad frente a las cepas de S. aureus, siendo los extracto de C. odorata, A. triplinervia y Caraipa grandiflora, los de mayor actividad con una CIM = 3.91 mg/ml para cada uno.  Se obtuvieron prometedores resultados de actividad antibacteriana de los extractos en estudio frente a cepas intrahospitalarias, mayormente contra S. aureus. Descriptores: Actividad antibacteriana, extractos vegetales, cepas intrahospitalarias Abstract The Amazon region is one of the areas with the largest biodiversity in the world, hosting several thousand species of plants, many of which are used by its people as medicinal plants. In recent years, the use of these plant resources or products has been increasing significantly, which could be due to a number of factors, among them the knowledge of their chemical composition, and the fact that at present there have been numerous pharmacological tests both in vivo and in vitro. The emergence of antibiotic-resistant strains in recent years, is creating a need for other strategies or ways to control them, as in the case of the use of plants (traditional medicine), because the active ingredients bearing. This work is intended to determine probable alternatives to combat bacterial infections of those agents antibiotic-resistant, this problem is particularly critical in developing countries, where perhaps there are no antibiotics or expensive second line, if any, price is unavailable. The study was conducted in Iquitos city, Province of Maynas, Department of Loreto. Microbiological tests were performed at Microbiology Laboratory of Research Center of Natural Resources of the Amazon (CIRNA) of the National University of the Peruvian Amazon (UNAP). The antibacterial activity of six plant extracts (Alchornea triplinervia, Annona muricata, Averrhoa carambola, Brunfelsia grandiflora, Caraipa grandifolia y Cedrela odorata) by the disk diffusion method was determined, and those that showed activity were determined Minimum Inhibitory Concentration and Minimum Bactericidal Concentration by macrodilution technique. None of the extracts were active against strains of E. coli; four extracts had activity against strains of P. aeruginosa, with Cedrela odorata and Alchornea triplinervia extracts which had greater activity against these bacteria, with MIC = 15.62 and 62.5 mg/ml, respectively; all extracts were active against strains of S. aureus, with the extract of C. odorata, A. triplinervia and Caraipa grandiflora, the most active with an MIC = 3.91 mg/ml for each. Was obtained Promising results of antibacterial activity of the extracts in study against nosocomial strains, mostly against S. aureus. Keywords: Antibacterial activity, plant extracts, nosocomial strains

scholarly journals Myrobalans Mediated Nanocolloids in Controlling Marine Pathogens

2021 ◽  
Author(s):  
Ranjani S ◽  
Pradeep Parthasarathy ◽  
Rameshkumar p ◽  
Hemalatha S
Keyword(s):  
Zeta Potential ◽  
Biofilm Formation ◽  
Foodborne Pathogen ◽  
Disease Outbreak ◽  
Infected Fish ◽  
Antibiotic Resistant ◽  
Vis Spectroscopy ◽  
Aquaculture Industry ◽  
Genes Encoding ◽  
Aquaculture Production

Abstract Aquaculture production is affected by disease outbreak, which affect the production, profitability, and sustainability of the global aquaculture industry. Antibiotics have been widely used to control various pathogens. Due to its uncontrollable and indiscriminate usage, pathogens have developed resistance towards antibiotics. This current study aims to synthesize green silver- of silver nanocolloids (MBNc) from the extract of three myrobalans. MBNc was characterized by using UV-Vis spectroscopy, DLS, Zeta potential, FE-SEM. EDX, HRTEM, and SAED techniques. The array of antimicrobial assays were performed to evaluate the efficacy of MBNc against vibriosis causing pathogens including V. harveyi, V. alginolyticus, V. parahaemolyticus, and foodborne pathogen S. haemolyticus, isolated from infected fish. Further, the presence of ESBL genes including CTX-M-15 and Amp C were analyzed in control and MBNc treated strains. From our studies, it was observed that MBNc was very effective in controlling the growth and biofilm formation in all tested marine pathogens and effectively abolish the genes encoding ESBL CTX-M-15 in antibiotic-resistant pathogens tested. Thus, MBNc can be formulated to control the growth of marine pathogens and it can be used as an alternative to antibiotics to prevent infection in cage culturing and aquafarming.

scholarly journals Truncation of poly-N-acetylglucosamine (PNAG) polymerization with N-acetylglucosamine analogues

2021 ◽  
Author(s):  
Zachary Morrison ◽  
Alexander Eddenden ◽  
Adithya S Subramanian ◽  
P. Lynne Howell ◽  
mark nitz
Keyword(s):  
Biofilm Formation ◽  
Chain Termination ◽  
Salvage Pathway ◽  
Biofilm Inhibition ◽  
E Coli ◽  
Substrate Analogues

Bacteria require polysaccharides for structure, survival, and virulence. Despite the central role these structures play in microbiology few tools are available to manipulate their production. In E. coli the glycosyltransferase complex PgaCD produces poly-N-acetylglucosamine (PNAG), an extracellular matrix polysaccharide required for biofilm formation. We report that C6-substituted (H, F, N3, SH, NH2) UDP-GlcNAc substrate analogues are inhibitors of PgaCD. In vitro the inhibitors cause PNAG chain termination; consistent with the mechanism of PNAG polymerization from the non-reducing terminus. In vivo, expression of the GlcNAc-1-kinase NahK in E. coli provided a non-native GlcNAc salvage pathway that produced the UDP-GlcNAc analogue inhibitors in situ. The 6-fluoro and 6-deoxy derivatives were potent inhibitors of biofilm formation in the transformed strain, providing a tool to manipulate this key exopolysaccharide. Characterization of the UDP-GlcNAc pool and quantification of PNAG generation support PNAG termination as the primary in vivo mechanism of biofilm inhibition by 6-fluoro UDP-GlcNAc.

scholarly journals Fimbrial Profiles Predict Virulence of Uropathogenic Escherichia coli Strains: Contribution of Ygi and Yad Fimbriae

2011 ◽  
Vol 79 (12) ◽  
pp. 4753-4763 ◽  
Author(s):  
Rachel R. Spurbeck ◽  
Ann E. Stapleton ◽  
James R. Johnson ◽  
Seth T. Walk ◽  
Thomas M. Hooton ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Mouse Model ◽  
Cell Line ◽  
Biofilm Formation ◽  
Asymptomatic Bacteriuria ◽  
Wild Type ◽  
Content Type ◽  
E Coli ◽  
Tract Infections

ABSTRACTEscherichia coli, a cause of ∼90% of urinary tract infections (UTI), utilizes fimbrial adhesins to colonize the uroepithelium. Pyelonephritis isolateE. coliCFT073 carries 12 fimbrial operons, 5 of which have never been studied. Using multiplex PCR, the prevalence of these 12 and 3 additional fimbrial types was determined for a collection of 303E. coliisolates (57 human commensal, 32 animal commensal, 54 asymptomatic bacteriuria, 45 complicated UTI, 38 uncomplicated cystitis, and 77 pyelonephritis). The number of fimbrial types perE. coliisolate was distributed bimodally: those with low (3.2 ± 1.1) and those with high (8.3 ± 1.3) numbers of fimbrial types (means ± standard errors of the means). The fimbrial genesygiL,yadN,yfcV, andc2395were significantly more prevalent among urine isolates than human commensal isolates. The effect of deletion of Ygi and Yad fimbrial operons on growth, motility, biofilm formation, adherence to immortalized human epithelial cells, and pathogenesis in the mouse model of UTI was examined. Yad fimbriae were necessary for wild-type levels of adherence to a bladder epithelial cell line and for biofilm formation. Deletion of these fimbrial genes increased motility. Ygi fimbriae were necessary for wild-type levels of adherence to a human embryonic kidney cell line, biofilm formation, andin vivofitness in the urine and kidneys. Complementation of each fimbrial mutant restored wild-type levels of motility, biofilm formation, adherence and, forygi,in vivofitness. A double deletion strain, Δygi Δyad, was attenuated in the urine, bladder, and kidneys in the mouse model, demonstrating that these fimbriae contribute to uropathogenesis.

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