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biofilm producing E. coli

Xiaobei Wang, Huaixu Cheng, Mingsheng Lu, Yaowei Fang, Yuliang Jiao, Weijuan Li, Gengmao Zhao, Shujun Wang
Dental plaque is a biofilm of water-soluble and water-insoluble polysaccharides, produced primarily by Streptococcus mutans. Dextranase can inhibit biofilm formation. Here, a dextranase gene from the marine microorganism Arthrobacter oxydans KQ11-1 is described, and cloned and expressed using E. coli DH5α competent cells. The recombinant enzyme was then purified and its properties were characterized. The optimal temperature and pH were determined to be 60°C and 6.5, respectively. High-performance liquid chromatography data show that the final hydrolysis products were glucose, maltose, maltotriose, and maltotetraose...
November 2016: Biofouling
Santosh Kumar Singh, Seema Kumari, Minakshi Gupta
Escherichia coli mediated urinary tract infection has been reported to be most prevalent among patients of different class, gender and ages. Currently, multidrug resistant E. coli harboring several virulence factors are most perilous threats for patients especially for elders. The aim of this study was to determine the antibiotic resistance pattern, co-resistance and phenotypic virulence factors present in uropathogenic E. coli isolates from aged patients. Thirty-nine E. coli isolates were collected during May-June 2014 from patients aged 50-80 years...
October 12, 2016: Microbial Pathogenesis
David A Hufnagel, Margery L Evans, Sarah E Greene, Jerry S Pinkner, Scott J Hultgren, Matthew R Chapman
The extracellular matrix protects Escherichia coli from immune cells, oxidative stress, predation, and other environmental stresses. Production of the E. coli extracellular matrix is regulated by transcription factors that are tuned to environmental conditions. The biofilm master-regulator protein CsgD upregulates curli and cellulose, the two major polymers in the extracellular matrix of uropathogenic E. coli (UPEC) biofilms. Here, we found that cAMP regulates curli, cellulose, and UPEC biofilms through csgD The alarmone cAMP is produced by adenylate cyclase (CyaA) and deletion of cyaA resulted in lower extracellular matrix production and biofilm formation...
October 3, 2016: Journal of Bacteriology
Leanid Laganenka, Remy Colin, Victor Sourjik
Bacteria communicate by producing and sensing extracellular signal molecules called autoinducers. Such intercellular signalling, known as quorum sensing, allows bacteria to coordinate and synchronize behavioural responses at high cell densities. Autoinducer 2 (AI-2) is the only known quorum-sensing molecule produced by Escherichia coli but its physiological role remains elusive, although it is known to regulate biofilm formation and virulence in other bacterial species. Here we show that chemotaxis towards self-produced AI-2 can mediate collective behaviour-autoaggregation-of E...
2016: Nature Communications
Vicente Bernal, Sara Castaño-Cerezo, Manuel Cánovas
Acetate is ubiquitously found in natural environments. Its availability in the gut is high as a result of the fermentation of nutrients, and although it is rapidly absorbed by intestinal mucosa, it can also be used as carbon source by some members of gut microbiota. The metabolism of acetate in Escherichia coli has attracted the attention of the scientific community due to its role in central metabolism and its link to multiple physiological features. In this microorganism, acetate is involved directly or indirectly on the regulation of functional processes, such as motility, formation of biofilms, and responses to stress...
November 2016: Applied Microbiology and Biotechnology
Shelly L Pringle, Kelli L Palmer, Robert J C McLean
Escherichia coli lives in the gastrointestinal tract and elsewhere, where it coexists within a mixed population. Indole production enables E. coli to grow with other gram-negative bacteria as indole inhibits N-acyl-homoserine lactone (AHL) quorum regulation. We investigated whether E. coli indole production enhanced competition with gram-positive Enterococcus faecalis, wherein quorum signaling is mediated by small peptides. During planktonic co-culture with E. faecalis, the fitness and population density of E...
September 16, 2016: Archives of Microbiology
Malena E Skogman, Sonja Kanerva, Suvi Manner, Pia M Vuorela, Adyary Fallarero
Quorum sensing (QS) is the process by which bacteria produce and detect signal molecules to coordinate their collective behavior. This intercellular communication is a relevant target for anti-biofilm therapies. Here we have optimized a screening-applicable assay to search for new quorum sensing inhibitors from natural compound libraries. In this system, QS is correlated with the production of violacein, which is directly controlled by the LuxI/LuxR system in Chromobacterium violaceum ATCC 31532. The parallel use of C...
2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Marie C Maher, Ji Youn Lim, Cheston Gunawan, Lynette Cegelski
Escherichia coli assemble functional amyloid fibers termed curli that contribute to bacterial adhesion, biofilm formation, and host pathogenesis. We developed a cell-based high-throughput screen to identify inhibitors of curli-mediated adhesion in the laboratory strain MC4100 and curli-associated biofilm formation in the uropathogenic E. coli clinical isolate UTI89. Inhibitors of biofilm formation can operate through many mechanisms, and such inhibitors could hold therapeutic value in preventing and treating urinary tract infections...
October 9, 2015: ACS Infectious Diseases
Yuen Wah Chan, Kim Shyong Siow, Pei Yuen Ng, Usup Gires, Burhanuddin Yeop Majlis
Antibacterial coating is important to prevent the colonization of medical devices by biofilm forming bacteria that would cause infection and sepsis in patients. Current coating techniques such as immobilization of antimicrobial compounds, time-releasing antibiotic agents and silver nanoparticles, require multiple processing steps, and they have low efficacy and low stability. We proposed a single-step plasma polymerization of an essential oil known as carvone to produce a moderately hydrophobic antibacterial coating (ppCar) with an average roughness of <1nm...
November 1, 2016: Materials Science & Engineering. C, Materials for Biological Applications
Anirudha Dutta, Sudipta Bhattacharyya, Anirban Kundu, Debabrata Dutta, Amit Kumar Das
Staphylococcus aureus is a commensal and opportunistic pathogen that causes lethal infections. Biofilm forming ability of S. aureus enhances its virulence since biofilm provides the bacteria protective shield against antibiotics and host immunity. Polysaccharide independent biofilm formation by several virulent S. aureus strains have been identified recently, where protein components substitute polysaccharide intercellular adhesin (PIA) involved in bacterial cell attachment. The suhB gene has been reported to be essential in staphylococcal PIA-independent biofilm formation...
October 2016: Biophysical Chemistry
Naoko Imuta, Tadasuke Ooka, Kazuko Seto, Ryuji Kawahara, Toyoyasu Koriyama, Tsuyoshi Kojyo, Atsushi Iguchi, Koichi Tokuda, Hideki Kawamura, Kiyotaka Yoshiie, Yoshitoshi Ogura, Tetsuya Hayashi, Junichiro Nishi
Enteroaggregative Escherichia coli (EAEC) causes acute or persistent diarrhea. The aggR gene is widely used as a marker for typical EAEC. The heterogeneity of EAEC is well known; however, there are few reports on the phylogenetic relationships of EAEC. Recently, CTX-M extended-spectrum β-lactamase (ESBL)-producing EAEC strains have been reported worldwide. To characterize EAEC strains in Japan, we investigated the population structure of EAEC. A total of 167 aggR-positive strains isolated from stool specimens from diarrheal patients in Kagoshima (139 strains) and Osaka (28 strains), Japan, between 1992 and 2010 were examined for the prevalence of EAEC virulence markers, the blaCTX-M gene, and the capacity to form biofilms...
August 2016: Journal of Clinical Microbiology
José María Gómez Gómez, Jesús Medina, Fernando Rull
UNLABELLED: Biosaline formations (BSFs) are complex self-organized biomineral patterns formed by "hibernating" bacteria as the biofilm that contains them dries out. They were initially described in drying biofilms of Escherichia coli cells + NaCl. Due to their intricate 3-D morphology and anhydrobiosis, these biomineralogical structures are of great interest in astrobiology. Here we report experimental data obtained with various alkali halide salts (NaF, NaCl, NaBr, LiCl, KCl, CsCl) on BSF formation with E...
July 2016: Astrobiology
Kyle A Floyd, Courtney A Mitchell, Allison R Eberly, Spencer J Colling, Ellisa W Zhang, William DePas, Matthew R Chapman, Matthew Conover, Bridget R Rogers, Scott J Hultgren, Maria Hadjifrangiskou
UNLABELLED: Uropathogenic Escherichia coli (UPEC), which causes the majority of urinary tract infections (UTI), uses pilus-mediated adherence to initiate biofilm formation in the urinary tract. Oxygen gradients within E. coli biofilms regulate expression and localization of adhesive type 1 pili. A transposon mutant screen for strains defective in biofilm formation identified the ubiI (formerly visC) aerobic ubiquinone synthase gene as critical for UPEC biofilm formation. In this study, we characterized a nonpolar ubiI deletion mutant and compared its behavior to that of wild-type bacteria grown under aerobic and anoxic conditions...
October 1, 2016: Journal of Bacteriology
Attila Nagy, Yunfeng Xu, Gary R Bauchan, Daniel R Shelton, Xiangwu Nou
The Shiga toxigenic Escherichia coli O104:H4 isolated during the 2011 European outbreak expresses Shiga toxin 2a and possess virulence genes associated with the enteroaggregative E. coli (EAEC) pathotype. It produces plasmid encoded aggregative adherence fimbriae I (AAF/I) which mediate cell aggregation and biofilm formation in human intestine and promote Shiga-toxin adsorption, but it is not clear whether the AAF/I fimbriae are involved in the colonization and biofilm formation on food and environmental matrices such as the surface of fresh produce...
July 16, 2016: International Journal of Food Microbiology
Bruna G Garcia, Tadasuke Ooka, Yasuhiro Gotoh, Mônica A M Vieira, Denise Yamamoto, Yoshitoshi Ogura, Dennys M Girão, Suely C F Sampaio, Alexis Bonfim Melo, Kinue Irino, Tetsuya Hayashi, Tânia A T Gomes
Enteropathogenic Escherichia coli (EPEC) induce attaching and effacing (A/E) lesions in enterocytes and produce the bundle-forming pilus (BFP) contributing to the localized adherence (LA) pattern formation on HeLa cells. Enteroaggregative E. coli (EAEC) produce aggregative adherence (AA) on HeLa cells and form prominent biofilms. The ability to produce LA or AA is an important hallmark to classify fecal E. coli isolates as EPEC or EAEC, respectively. E. coli strains of serotype O119:H6 exhibit an LA+ phenotype and have been considered as comprising a clonal group of EPEC strains...
May 2016: International Journal of Medical Microbiology: IJMM
Charlotte Sahlberg Bang, Robert Kruse, Kjell Johansson, Katarina Persson
BACKGROUND: Increased resistance to antimicrobial agents is a characteristic of many bacteria growing in biofilms on for example indwelling urinary catheters or in intracellular bacterial reservoirs. Biofilm-related infections caused by multidrug-resistant bacteria, such as extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, are a major challenge. The aim of this study was to investigate if a carbon monoxide-releasing molecule (CORM-2) has antibacterial effects against ESBL-producing uropathogenic E...
2016: BMC Microbiology
Michelle Qiu Carter, Jacqueline W Louie, Doris Feng, Wayne Zhong, Maria T Brandl
Several species of enteric pathogens produce curli fimbriae, which may affect their interaction with surfaces and other microbes in nonhost environments. Here we used two Escherichia coli O157:H7 outbreak strains with distinct genotypes to understand the role of curli in surface attachment and biofilm formation in several systems relevant to fresh produce production and processing. Curli significantly enhanced the initial attachment of E. coli O157:H7 to spinach leaves and stainless steel surfaces by 5-fold...
August 2016: Food Microbiology
Laura Iveth Miranda-Estrada, María Ruíz-Rosas, José Molina-López, Isela Parra-Rojas, Edgar González-Villalobos, Natividad Castro-Alarcón
INTRODUCTION: Escherichia coli is the major causative agent of urinary tract infections (UTI), and virulence factors are responsible for the severity of these emerging infections. The aim of this study was to evaluate the relationship between virulence determinants and antibiotic susceptibility with phylogenetic groups of E.coli isolates of UTI in two locations in Mexico. METHODS: An analysis was performed on 50 isolates of E.coli from the centre of the country and 57 from a town in the southwest...
April 2, 2016: Enfermedades Infecciosas y Microbiología Clínica
Elahe Tajbakhsh, Parvin Ahmadi, Elham Abedpour-Dehkordi, Nazila Arbab-Soleimani, Faham Khamesipour
BACKGROUND: Uropathogenic Escherichia coli O- Serogroups with their virulence factors are the most prevalent causes of UTIs. The present research performed to track common uropathogenic E.coli serogroups, antibiotic resistance pattern of strains and prevalence of virulence genes in isolations having the ability to constitute biofilm. METHODS: In this research 130 E.coli isolation from patients having UTI symptoms were collected and antimicrobial resistance pattern was performed by Kirby-Bauer method...
2016: Antimicrobial Resistance and Infection Control
Katharina Schaufler, Torsten Semmler, Derek J Pickard, María de Toro, Fernando de la Cruz, Lothar H Wieler, Christa Ewers, Sebastian Guenther
Pathogenic ESBL-producing E. coli lineages occur frequently worldwide, not only in a human health context but in animals and the environment, also in settings with low antimicrobial pressures. This study investigated the fitness costs of ESBL-plasmids and their influence on chromosomally encoded features associated with virulence, such as those involved in the planktonic and sessile behaviors of ST131 and ST648 E. coli. ESBL-plasmid-carrying wild-type E. coli strains, their corresponding ESBL-plasmid-"cured" variants (PCV), and complementary ESBL-carrying transformants were comparatively analyzed using growth curves, Omnilog® phenotype microarray (PM) assays, macrocolony and biofilm formation, swimming motility, and RNA sequence analysis...
2016: Frontiers in Microbiology
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