UpaG, a New Member of the Trimeric Autotransporter Family of Adhesins in Uropathogenic Escherichia coli

ABSTRACT The ability of Escherichia coli to colonize both intestinal and extraintestinal sites is driven by the presence of specific virulence factors, among which are the autotransporter (AT) proteins. Members of the trimeric AT adhesin family are important virulence factors for several gram-negative pathogens and mediate adherence to eukaryotic cells and extracellular matrix (ECM) proteins. In this study, we characterized a new trimeric AT adhesin (UpaG) from uropathogenic E. coli (UPEC). Molecular analysis of UpaG revealed that it is translocated to the cell surface and adopts a multimeric conformation. We demonstrated that UpaG is able to promote cell aggregation and biofilm formation on abiotic surfaces in CFT073 and various UPEC strains. In addition, UpaG expression resulted in the adhesion of CFT073 to human bladder epithelial cells, with specific affinity to fibronectin and laminin. Prevalence analysis revealed that upaG is strongly associated with E. coli strains from the B2 and D phylogenetic groups, while deletion of upaG had no significant effect on the ability of CFT073 to colonize the mouse urinary tract. Thus, UpaG is a novel trimeric AT adhesin from E. coli that mediates aggregation, biofilm formation, and adhesion to various ECM proteins.

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Novel Roles for the AIDA Adhesin from Diarrheagenic Escherichia coli: Cell Aggregation and Biofilm Formation

Journal of Bacteriology ◽

10.1128/jb.186.23.8058-8065.2004 ◽

2004 ◽

Vol 186 (23) ◽

pp. 8058-8065 ◽

Cited By ~ 128

Author(s):

Orla Sherlock ◽

Mark A. Schembri ◽

Andreas Reisner ◽

Per Klemm

Keyword(s):

Escherichia Coli ◽

Biofilm Formation ◽

Mammalian Cells ◽

Gastrointestinal Disease ◽

Cell Aggregation ◽

Bacterial Attachment ◽

E Coli ◽

Abiotic Surfaces ◽

Broad Variety ◽

Self Association

ABSTRACT Diarrhea-causing Escherichia coli strains are responsible for numerous cases of gastrointestinal disease and constitute a serious health problem throughout the world. The ability to recognize and attach to host intestinal surfaces is an essential step in the pathogenesis of such strains. AIDA is a potent bacterial adhesin associated with some diarrheagenic E. coli strains. AIDA mediates bacterial attachment to a broad variety of human and other mammalian cells. It is a surface-displayed autotransporter protein and belongs to the selected group of bacterial glycoproteins; only the glycosylated form binds to mammalian cells. Here, we show that AIDA possesses self-association characteristics and can mediate autoaggregation of E. coli cells. We demonstrate that intercellular AIDA-AIDA interaction is responsible for bacterial autoaggregation. Interestingly, AIDA-expressing cells can interact with antigen 43 (Ag43)-expressing cells, which is indicative of an intercellular AIDA-Ag43 interaction. Additionally, AIDA expression dramatically enhances biofilm formation by E. coli on abiotic surfaces in flow chambers.

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Role of Enteroaggregative Escherichia coli Virulence Factors in Uropathogenesis

Infection and Immunity ◽

10.1128/iai.01376-12 ◽

2013 ◽

Vol 81 (4) ◽

pp. 1164-1171 ◽

Cited By ~ 42

Author(s):

Erik J. Boll ◽

Carsten Struve ◽

Nadia Boisen ◽

Bente Olesen ◽

Steen G. Stahlhut ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Factors ◽

Outbreak Strain ◽

Content Type ◽

E Coli ◽

Abiotic Surfaces ◽

Extraintestinal Disease ◽

First Time ◽

Specific Virulence

ABSTRACTA multiresistant clonalEscherichia coliO78:H10 strain qualifying molecularly as enteroaggregativeEscherichia coli(EAEC) was recently shown to be the cause of a community-acquired outbreak of urinary tract infection (UTI) in greater Copenhagen, Denmark, in 1991. This marks the first time EAEC has been associated with an extraintestinal disease outbreak. Importantly, the outbreak isolates were recovered from the urine of patients with symptomatic UTI, strongly implying urovirulence. Here, we sought to determine the uropathogenic properties of the Copenhagen outbreak strain and whether these properties are conferred by the EAEC-specific virulence factors. We demonstrated that through expression of aggregative adherence fimbriae, the principal adhesins of EAEC, the outbreak strain exhibited pronouncedly increased adherence to human bladder epithelial cells compared to prototype uropathogenic strains. Moreover, the strain was able to produce distinct biofilms on abiotic surfaces, including urethral catheters. These findings suggest that EAEC-specific virulence factors increase uropathogenicity and may have played a significant role in the ability of the strain to cause a community-acquired outbreak of UTI. Thus, inclusion of EAEC-specific virulence factors is warranted in future detection and characterization of uropathogenicE. coli.

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Escherichia coli Strains with Virulent Factors Typical for Uropathogens were Isolated from Sinuses from Patients with Chronic Rhinosinusitis—Case Report

Pathogens ◽

10.3390/pathogens9050318 ◽

2020 ◽

Vol 9 (5) ◽

pp. 318

Author(s):

Beata Krawczyk ◽

Michał Michalik ◽

Magdalena Fordon ◽

Magdalena Wysocka ◽

Alfred Samet ◽

...

Keyword(s):

Escherichia Coli ◽

Chronic Rhinosinusitis ◽

Virulence Factors ◽

Previous Treatment ◽

Uptake System ◽

E Coli ◽

Fitness Advantage ◽

Pcr Method ◽

The Rich ◽

Specific Virulence

Escherichia coli were isolated from three patients with chronic rhinosinusitis (CRS) by intraoperative sinus tissue biopsy. Taking into account the unusual replicative niche and previous treatment failures, it was decided to focus on the virulence and drug resistance of these bacteria. The strains turned out to be multi-sensitive, but the rich virulence factors profile of bacteria typical for phylogenetic group B2 deserved attention. Tests were carried out for the presence of 32 genes using the PCR method. Particularly noteworthy are the toxins Cnf-1, HlyA, Usp—an extensive iron uptake system (enterobactin, salmochelin, yersiniabactin and outer membrane hemin receptor ChuA)—SPATE autotransporters such as vat and pic, Ag43 autoaggregative protein—important for biofilm formation—and TosA/B which enhance the fitness of E.coli. All these virulence factors are identified predominantly in UPEC strains and provide a fitness advantage during colonization of the sinuses. Patients with CRS should be asked for past or present UTI. The specific virulence factors of E. coli that facilitate the colonization of the GI tract and urinary tract may also favor the colonization of a new ecological niche (sinuses) as a result of microbial imbalance or dysbiosis.

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Virulence factors and phylogenetic group profile of uterine Escherichia coli in early postpartum of high-producing dairy cows

Animal Production Science ◽

10.1071/an17729 ◽

2019 ◽

Vol 59 (10) ◽

pp. 1898

Author(s):

Luana de Cássia Bicudo ◽

Eunice Oba ◽

Sony Dimas Bicudo ◽

Domingos da Silva Leite ◽

Amanda Keller Siqueira ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Factors ◽

Pasteurella Multocida ◽

Anaerobic Bacteria ◽

Sampling Time ◽

Phylogenetic Groups ◽

E Coli ◽

Haemolytic Streptococcus ◽

Early Postpartum ◽

Group Profile

Escherichia coli is the most common contaminant of the bovine uterus in the first few weeks postpartum, and one of the most important pathogens involved in uterine infections. This bacterium is characterised by diverse virulence factors (VF); however, the profile of E. coli VF in physiologic postpartum uterine contamination is not well established. Therefore, the present study aimed to investigate the prevalence of intrauterine bacteria, a set of virulence factors and phylogroups of E. coli isolates, leukogram and uterine cytology in 75 Holstein cows at 24 h (Sampling time 1) and 14 days (Sampling time 2) postpartum. Escherichia coli, α-haemolytic Streptococcus, Trueperella pyogenes, and Pasteurella multocida were the most common microorganisms isolated in pure culture, whereas E. coli and Clostridium perfringens Type A, E. coli and α-haemolytic Streptococcus, and E. coli and Proteus mirabilis were the most frequent microorganisms in mixed colonies at both studied sampling times. In the 59 E. coli isolates after 24 h (n = 35) and 14 days (n = 24) postpartum, the genes detected for VF were fimH, iucD/aer, kps, hlyA, usp, vt1 and vt2. Most E. coli strains detected in both moments of study belonged to Commensal phylogenetic groups A and B1, whereas Pathogenic groups D and B2 were identified at 24 h and 14 days postpartum respectively. All cows presented suitable immune response against the presence of bacteria in uterine lumen, observed by leukocytosis, neutrophilia, lymphocytosis and monocytosis at leukogram and a high number of polymorphonuclear leukocytes in uterine cytology, in both studied moments. Thus, a complex diversity of aerobic and anaerobic bacteria is involved in uterine contamination in the early postpartum of cows, besides the predominance of E. coli. Moreover, the genes fimH, iucD/aer, hlyA, kps, usp, vt1 and vt2 play a key role in the virulence of E. coli in this period.

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The TibA Adhesin/Invasin from Enterotoxigenic Escherichia coli Is Self Recognizing and Induces Bacterial Aggregation and Biofilm Formation

Infection and Immunity ◽

10.1128/iai.73.4.1954-1963.2005 ◽

2005 ◽

Vol 73 (4) ◽

pp. 1954-1963 ◽

Cited By ~ 93

Author(s):

Orla Sherlock ◽

Rebecca Munk Vejborg ◽

Per Klemm

Keyword(s):

Escherichia Coli ◽

Biofilm Formation ◽

Mammalian Cells ◽

Gastrointestinal Disease ◽

Bacterial Attachment ◽

Enterotoxigenic Escherichia Coli ◽

E Coli ◽

Abiotic Surfaces ◽

Self Association ◽

Exclusive Group

ABSTRACT Escherichia coli strains are responsible for many cases of gastrointestinal disease and represent a serious health problem worldwide. An essential step in the pathogenesis of such strains involves recognition and attachment to host intestinal surfaces. TibA is a potent bacterial adhesin associated with a number of enterotoxigenic E. coli strains and mediates bacterial attachment to a variety of human cells; additionally, it promotes invasion of such cells. This adhesin is a surface-displayed autotransporter protein and belongs to the exclusive group of bacterial glycoproteins; only the glycosylated form confers binding to and invasion of mammalian cells. Here we characterized TibA and showed that it possesses self-association characteristics and can mediate autoaggregation of E. coli cells. We demonstrated that intercellular TibA-TibA interaction is responsible for bacterial autoaggregation. Also, TibA expression significantly enhances biofilm formation by E. coli on abiotic surfaces.

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Virulence genes and phylogenetic groups of uropathogenic Escherichia coli isolates from patients with urinary tract infection and uninfected control subjects: a case-control study

BMC Infectious Diseases ◽

10.1186/s12879-021-06036-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Seyedeh Elham Rezatofighi ◽

Mahsa Mirzarazi ◽

Mansour Salehi

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Virulence Factors ◽

Virulence Genes ◽

Strong Association ◽

Phylogenetic Groups ◽

E Coli ◽

Healthy Humans

Abstract Background Urinary Tract Infection (UTI) is one of the most common bacterial infectious diseases which causes considerable morbidity and costly health problems. Uropathogenic Escherichia coli (UPEC), the most common pathogen causing UTI, is a highly heterogeneous group of extraintestinal pathogenic E. coli (ExPEC) which may carry a variety of virulence factors and belonging to different phylogenetic backgrounds. The current study aimed to investigate the frequency and association between various virulence factors (VFs) and phylogenetic groups of UPEC and commensal isolates. Methods UPEC and commensal E. coli strains isolated from UTI and feces of healthy humans were compared for the presence of VFs and phylogenetic groups. Association between virulence genes was investigated and cluster analysis was employed. Results According to the results, among a 30 virulence markers tested, the pathogenicity-associated island (PAI), papAH, papEF, fimH, fyuA, and traT genes prevalence were statistically significant in UPEC isolates. A strong association was found between the B2 and D phylogenetic groups and clinical isolates of UPEC; while, commensal isolates were mostly associated with phylogenetic group A. The aggregated VFs scores were more than twice higher in the UPEC isolates in comparison with the commensal isolates. Interestingly, the B2 group in both UPEC and commensal isolates had the highest VF scores. A strong positive association was found between several virulence genes. The clustering results demonstrated that UPEC or commensal E. coli isolates were highly heterogeneous due to different composition of their virulence gene pool and pathogenicity islands. Conclusion Genetic structure and VFs of UPEC strains vary from region to region; therefore, to control the UTI, the epidemiological aspects and characterization of the UPEC isolates need to be investigated in different regions. Since UPEC isolates are generally originate from the commensal strains, it may be feasible to reduce the UTI burden by interfering the intestinal colonization, particularly in the highly pathogenic clonal lineages such as B2.

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Antimicrobial resistance among canine enteric Escherichia coli isolates and prevalence of attaching–effacing and extraintestinal pathogenic virulence factors in Spain

Acta Veterinaria Hungarica ◽

10.1556/004.2020.00013 ◽

2020 ◽

Vol 68 (1) ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Eloisa Sevilla ◽

Raúl C. Mainar-Jaime ◽

Bernardino Moreno ◽

Inmaculada Martín-Burriel ◽

Mariano Morales ◽

...

Keyword(s):

Escherichia Coli ◽

Multidrug Resistance ◽

Antimicrobial Resistance ◽

Virulence Factors ◽

Shiga Toxin ◽

E Coli ◽

Extended Spectrum ◽

Specific Virulence

AbstractThe aim of this study was to estimate the prevalence of antimicrobial resistance (AMR) in Escherichia coli from a dog population in Spain and assess specific virulence factors. Susceptibility to 22 antimicrobials was tested along with the production of extended-spectrum β-lactamases (ESBLs) and AmpC in faecal isolates from 100 dogs. Virulence-related genes associated with attaching and effacing E. coli (eae, Stx1, Stx2) and extraintestinal pathogenic E. coli – ExPEC – (papC, hlyA and cnf1) were detected by PCR. At least one kind of AMR was observed in 73% of the isolates. The highest prevalences corresponded to penicillin (45%), aminoglycoside (40%) and non-extended spectrum cephalosporin (39%) classes. Multidrug resistance (MDR) was observed in 53.4% of the resistant isolates. No resistance to colistin was found. Production of ESBL/AmpC enzymes was detected in 5% of E. coli. Shiga toxin-producing E. coli were not observed, enteropathogenic E. coli were identified in only 12% of them, and ExPEC were found in 25%. Dog faeces can be a source of E. coli strains potentially presenting a threat to humans through their virulence factors or AMR. The non-hygienic keeping of animals may increase the risk of colonisation of such pathogens in humans.

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Carbapenem Resistance Profiles of Pathogenic Escherichia coli in Uganda

European Journal of Biology and Biotechnology ◽

10.24018/ejbio.2021.2.2.171 ◽

2021 ◽

Vol 2 (2) ◽

pp. 63-73

Author(s):

Kenneth Ssekatawa ◽

Denis K. Byarugaba ◽

Jesca L. Nakavuma ◽

Charles D. Kato ◽

Francis Ejobi ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Factors ◽

Virulence Genes ◽

Carbapenem Resistance ◽

Phylogenetic Group ◽

Clinical Isolates ◽

Phylogenetic Groups ◽

Phenotypic Resistance ◽

E Coli ◽

Tract Infections

Escherichia coli has been implicated as one of the main etiological agents of diarrhea, urinary tract infections, meningitis and septicemia worldwide. The ability to cause diseases is potentiated by presence of virulence factors. The virulence factors influence the capacity of E. coli to infect and colonize different body systems. Thus, pathogenic E. coli are grouped into DEC strains that are mainly clustered in phylogenetic group B1 and A; ExPEC belonging to A, B2 and D. Coexistence of virulence and beta-lactamase encoding genes complicates treatment outcomes. Therefore, this study aimed at presenting the carbapenem resistance (CR) profiles among pathogenic E. coli. This was a retrospective cross-sectional study involving use of 421 archived E. coli clinical isolates collected in 2019 from four Uganda tertiary hospitals. The isolates were subjected to antibiotics sensitivity assays to determine phenotypic resistance. Four sets of multiplex PCR were performed to detect CR genes, DEC pathotypes virulence genes, ExPEC PAI and the E. coli phylogenetic groups. Antibiotic susceptibility revealed that all the 421 E. coli isolates used were MDR as they exhibited 100% resistance to more than one of the first-line antibiotics. The study registered phenotypic and genotypic CR prevalence of 22.8% and 33.0% respectively. The most predominant gene was blaOXA-48 with genotypic frequency of 33.0%, then blaVIM (21.0%), blaIMP (16.5%), blaKPC (14.8%) and blaNDM (14.8%). Spearman’s correlation revealed that presence of CR genes was highly associated with phenotypic resistance. Furthermore, of 421 MDR E. coli isolates, 19.7% harboured DEC virulence genes, where EPEC recorded significantly higher prevalence (10.8%) followed by S-ETEC (3.1%), STEC (2.9%), EIEC (2.0%) and L-ETEC (2.0%). Genetic analysis characterized 46.1% of the isolates as ExPEC and only PAI IV536 (33.0%) and PAI IICFT073 (13.1%) were detected. Phylogenetic group B2 was predominantly detected (41.1%), followed by A (30.2%), B1(21.6%), and D (7.1%). Furthermore, 38.6% and 23.1% of the DEC and ExPEC respectively expressed phenotypic resistance. Our results exhibited significant level of CR carriage among the MDR DEC and ExPEC clinical isolates belonging to phylogenetic groups B1 and B2 respectively. Virulence and CR genetic factors are mainly located on mobile elements. Thus, constitutes a great threat to the healthcare system as this promotes horizontal gene transfer.

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Isolation of an Escherichia coli strain mutant unable to form biofilm on polystyrene and to adhere to human pneumocyte cells: involvement of tryptophanase

Canadian Journal of Microbiology ◽

10.1139/w02-001 ◽

2002 ◽

Vol 48 (2) ◽

pp. 132-137 ◽

Cited By ~ 36

Author(s):

P Di Martino ◽

A Merieau ◽

R Phillips ◽

N Orange ◽

C Hulen

Keyword(s):

Escherichia Coli ◽

Biofilm Formation ◽

A549 Cells ◽

Coli Strain ◽

Gene Encoding ◽

Cell Monolayers ◽

E Coli ◽

Transposon Insertion ◽

Abiotic Surfaces ◽

Tryptophanase Activity

Escherichia coli adherence to biotic and abiotic surfaces constitutes the first step of infection by promoting colonization and biofilm formation. The aim of this study was to gain a better understanding of the relationship between E. coli adherence to different biotic surfaces and biofilm formation on abiotic surfaces. We isolated mutants defective in A549 pneumocyte cells adherence, fibronectin adherence, and biofilm formation by random transposition mutagenesis and sequential passages over A549 cell monolayers. Among the 97 mutants tested, 80 were decreased in biofilm formation, 8 were decreased in A549 cells adherence, 7 were decreased in their adherence to fibronectin, and 17 had no perturbations in either of the three phenotypes. We observed a correlation between adherence to fibronectin or A549 cells and biofilm formation, indicating that biotic adhesive factors are involved in biofilm formation by E. coli. Molecular analysis of the mutants revealed that a transposon insertion in the tnaA gene encoding for tryptophanase was associated with a decrease in both A549 cells adherence and biofilm formation by E. coli. The complementation of the tnaA mutant with plasmid-located wild-type tnaA restored the tryptophanase activity, epithelial cells adherence, and biofilm formation on polystyrene. The possible mechanism of tryptophanase involvement in E. coli adherence and biofilm formation is discussed.Key words: Escherichia coli, biofilm, adherence, A549 cells, fibronectin, tryptophanase.

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Virulence Genes in Expanded-Spectrum-Cephalosporin-Resistant and -Susceptible Escherichia coli Isolates from Treated and Untreated Chickens

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01996-15 ◽

2015 ◽

Vol 60 (3) ◽

pp. 1874-1877 ◽

Cited By ~ 1

Author(s):

S. Baron ◽

S. Delannoy ◽

S. Bougeard ◽

E. Larvor ◽

E. Jouy ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Virulence Factors ◽

Shiga Toxin ◽

Virulence Genes ◽

Phylogenetic Groups ◽

Content Type ◽

E Coli ◽

Heat Stable ◽

Intestinal Infections

This study investigated antimicrobial resistance, screened for the presence of virulence genes involved in intestinal infections, and determined phylogenetic groups ofEscherichia coliisolates from untreated poultry and poultry treated with ceftiofur, an expanded-spectrum cephalosporin. Results show that none of the 76 isolates appeared to be Shiga toxin-producingE. colior enteropathogenicE. coli. All isolates were negative for the major virulence factors/toxins tested (ehxA,cdt, heat-stable enterotoxin [ST], and heat-labile enterotoxin [LT]). The few virulence genes harbored in isolates generally did not correlate with isolate antimicrobial resistance or treatment status. However, some of the virulence genes were significantly associated with certain phylogenetic groups.

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