Enterotoxigenic Escherichia coli (ETEC) is one of the most important causes of post-weaning diarrhea in piglets. Whilst serotype O149:F4 is frequently associated with hemorrhagic gastroenteritis, other serotypes have been found to be associated with mild or moderate enteritis. As neutrophils are recruited to sites of inflammation, the aim of this study was to ascertain whether or not there is any difference in the in vitro interaction between neutrophils and two different ETEC serotypes: O149:F4 and O147:F18. The association of bacteria with neutrophils was evaluated by flow cytometry. The respiratory burst was measured by the fluorescent probe dichlorofluorescein diacetate using flow cytometry and by L012-amplified chemiluminescence. The titers of antibodies against ETEC present in cultivation sera were assessed by agglutination. The viability of E. coli was ascertained by cultivation. It was found that the strains of O149 serotype were more frequently associated with neutrophils and induced a more intensive respiratory burst compared to the strains of O147 serotype. These differences might be due to the presence of different types of fimbriae on the surface of the strains tested and by the presence of anti-fimbrial antibodies in the porcine plasma. However, the intensive interaction between E. coli and the neutrophils and respiratory burst induced by the O149 strain did not lead to more efficient killing of the bacteria. It is suggested that a stronger respiratory burst may be an important factor causing severe clinical signs of post-weaning diarrhea in piglets.

• MeSH
• bakteriální fimbrie imunologie   MeSH
• enterotoxigenní Escherichia coli imunologie   MeSH
• infekce vyvolané Escherichia coli krev   imunologie   mikrobiologie   veterinární   MeSH
• nemoci prasat krev   imunologie   mikrobiologie   MeSH
• neutrofily imunologie   mikrobiologie   MeSH
• prasata MeSH
• proteiny z Escherichia coli krev   imunologie   MeSH
• průjem krev   imunologie   mikrobiologie   veterinární   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• proteiny z Escherichia coli MeSH

Enterotoxigenic Escherichia coli (ETEC) and Shiga toxin-producing E. coli (STEC) strains are the causative agents of severe foodborne diseases in both humans and animals. In this study, porcine pathogenic E. coli strains (n = 277) as well as porcine commensal strains (n = 188) were tested for their susceptibilities to 34 bacteriocin monoproducers to identify the most suitable bacteriocin types inhibiting porcine pathogens. Under in vitro conditions, the set of pathogenic E. coli strains was found to be significantly more susceptible to the majority of tested bacteriocins than commensal E. coli. Based on the production of bacteriocins with specific activity against pathogens, three potentially probiotic commensal E. coli strains of human origin were selected. These strains were found to be able to outcompete ETEC strains expressing F4 or F18 fimbriae in liquid culture and also decreased the severity and duration of diarrhea in piglets during experimental ETEC infection as well as pathogen numbers on the last day of in vivo experimentation. While the extents of the probiotic effect were different for each strain, the cocktail of all three strains showed the most pronounced beneficial effects, suggesting synergy between the tested E. coli strains. IMPORTANCE Increasing levels of antibiotic resistance among bacteria also increase the need for alternatives to conventional antibiotic treatment. Pathogenic Escherichia coli represents a major diarrheic infectious agent of piglets in their postweaning period; however, available measures to control these infections are limited. This study describes three novel E. coli strains producing antimicrobial compounds (bacteriocins) that actively inhibit a majority of toxigenic E. coli strains. The beneficial effect of three potentially probiotic E. coli strains was demonstrated under both in vitro and in vivo conditions. The novel probiotic candidates may be used as prophylaxis during piglets' postweaning period to overcome common infections caused by E. coli.

• Klíčová slova
• E. coli, ETEC, Escherichia, STEC, bacteriocin, pig, probiotic,
• MeSH
• bakteriální toxiny * metabolismus   MeSH
• bakteriociny metabolismus   terapeutické užití   MeSH
• Escherichia coli * účinky léků   genetika   metabolismus   MeSH
• faktory virulence genetika   MeSH
• feces mikrobiologie   MeSH
• infekce vyvolané Escherichia coli mikrobiologie   prevence a kontrola   veterinární   MeSH
• nemoci prasat mikrobiologie   prevence a kontrola   MeSH
• prasata MeSH
• probiotika terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie veterinární MeSH
• Názvy látek
• bakteriální toxiny * MeSH
• bakteriociny MeSH
• faktory virulence MeSH

The ability to adhere via colonization factors to specific receptors located on the intestinal mucosa is a key virulence factor in enterotoxigenic Escherichia coli (ETEC) pathogenesis. Here, the potential glycosphingolipid receptors of the novel human ETEC colonization factor CS30 were examined by binding of CS30-expressing bacteria to glycosphingolipids on thin-layer chromatograms. We thereby found a highly specific binding of CS30-expressing bacteria to a fast-migrating acid glycosphingolipid of human and porcine small intestine, while no binding was obtained with a mutant ETEC strain unable to express CS30 fimbriae. The CS30 binding glycosphingolipid from human small intestine was isolated and characterized by mass spectrometry as sulfatide (SO3-3Galβ1Cer). Comparative binding studies using sulfatides with different ceramide compositions gave a preferential binding of CS30 to sulfatide with d18:1-h24:0 ceramide. This ceramide species of sulfatide was also isolated from human small intestine and characterized by mass spectrometry and antibody binding. These studies implicate sulfatide as candidate receptor for mediating attachment of CS30-fimbriated ETEC to human and porcine small intestinal cells. Our findings may be a basis for designing receptor saccharide analogues for inhibition of the intestinal adhesion of CS30-expressing E. coli.

• Klíčová slova
• Enterotoxigenic E. coli, carbohydrate binding, colonization factor CS30, glycosphingolipid characterization, microbial adhesion, sulfatide,
• MeSH
• bakteriální adheze * MeSH
• ceramidy analýza   MeSH
• enterotoxigenní Escherichia coli metabolismus   MeSH
• faktory virulence metabolismus   MeSH
• glykosfingolipidy metabolismus   MeSH
• lidé MeSH
• prasata MeSH
• proteiny fimbrií genetika   metabolismus   MeSH
• proteiny z Escherichia coli metabolismus   MeSH
• střevní sliznice cytologie   mikrobiologie   MeSH
• sulfoglykosfingolipidy metabolismus   MeSH
• tenké střevo cytologie   mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ceramidy MeSH
• colonization factor antigens MeSH Prohlížeč
• faktory virulence MeSH
• glykosfingolipidy MeSH
• proteiny fimbrií MeSH
• proteiny z Escherichia coli MeSH
• sulfoglykosfingolipidy MeSH

Enterotoxigenic Escherichia coli (ETEC) is an extracellular bacterium that causes post-weaning diarrhoea (PWD) in piglets with different severity of clinical signs. The pathogenesis of ETEC is ascribed to the effect of enterotoxins. ETEC colonizes ileum and probably can penetrate the epithelium and stimulate macrophages. The aim of study was to examine whether there is any difference in cytokine response in vitro produced by two porcine cell lines, intestinal epithelial cell line (IPI-2I) and macrophage cell line (3D4/31) after stimulation with different serotypes of ETEC associated with different clinical course of PWD in piglets. Three serotypes, O149:K88 (F4), O147:F18 and O8:K88, were used. We observed that all the used serotypes were unable to induce IL-8 and TNF-alpha mRNA expression in IPI-2I cell line as measured by the real-time RT-PCR. In 3D4/31 cell line, we detected differences in cytokine response among the used serotypes. The highest IL-8 and TNF-alpha mRNA expression in 3D4/31 was detected after stimulation with serotype O149:K88 frequently associated with hemorrhagic gastroenteritis.

• MeSH
• buněčné linie MeSH
• cytokiny genetika   metabolismus   MeSH
• enterotoxigenní Escherichia coli fyziologie   MeSH
• epitelové buňky metabolismus   mikrobiologie   MeSH
• ileum fyziologie   MeSH
• makrofágy metabolismus   mikrobiologie   MeSH
• messenger RNA genetika   metabolismus   MeSH
• prasata MeSH
• regulace genové exprese fyziologie   MeSH
• střevní sliznice cytologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cytokiny MeSH
• messenger RNA MeSH

Enterotoxigenic and Shiga-toxigenic Escherichia coli (i.e., ETEC and STEC) are important causative agents of human and animal diseases. In humans, infections range from mild diarrhea to severe life-threating conditions, while infections of piglets result in lower weight gain and higher pig mortality with the accompanying significant economic losses. In this study, frequencies of four phylogenetic groups, fourteen virulence- and thirty bacteriocin determinants were analyzed in a set of 443 fecal E. coli isolates from diseased pigs and compared to a previously characterized set of 1283 human fecal E. coli isolates collected in the same geographical region. In addition, these characteristics were compared among ETEC, STEC, and non-toxigenic porcine E. coli isolates. Phylogenetic group A was prevalent among porcine pathogenic E. coli isolates, whereas the frequency of phylogroup B2, adhesion/invasion (fimA, pap, sfa, afaI, ial, ipaH, and pCVD432) and iron acquisition (aer and iucC) determinants were less frequent compared to human fecal isolates. Additionally, porcine isolates differed from human isolates relative to the spectrum of produced bacteriocins. While human fecal isolates encoded colicins and microcins with a similar prevalence, porcine pathogenic E. coli isolates produced predominantly colicins (94% of isolates); especially colicins B (42.6%), M (40.1%), and Ib (34.0%), which are encoded on large conjugative plasmids. The observed high prevalence of these colicin determinants suggests the importance of large colicinogenic plasmids and/or the importance of colicin production in intestinal inflammatory conditions.

• Klíčová slova
• Bacteriocin, Colicin, E. coli, ETEC, Pig, STEC,
• MeSH
• bakteriální adheze MeSH
• bakteriociny genetika   MeSH
• enterotoxigenní Escherichia coli genetika   patogenita   MeSH
• faktory virulence genetika   MeSH
• feces mikrobiologie   MeSH
• fylogeneze MeSH
• gastrointestinální trakt mikrobiologie   MeSH
• koliciny genetika   MeSH
• lidé MeSH
• mezibuněčné signální peptidy a proteiny MeSH
• plazmidy MeSH
• polymerázová řetězová reakce MeSH
• prasata MeSH
• proteiny fimbrií genetika   MeSH
• proteiny z Escherichia coli genetika   MeSH
• průjem mikrobiologie   MeSH
• shiga-toxigenní Escherichia coli genetika   patogenita   MeSH
• symbióza MeSH
• transportní proteiny genetika   MeSH
• železo metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• Aer protein, E coli MeSH Prohlížeč
• bakteriociny MeSH
• faktory virulence MeSH
• fimbrillin MeSH Prohlížeč
• ipaH protein, E coli MeSH Prohlížeč
• koliciny MeSH
• mezibuněčné signální peptidy a proteiny MeSH
• proteiny fimbrií MeSH
• proteiny z Escherichia coli MeSH
• transportní proteiny MeSH
• železo MeSH

Outer membrane vesicles (OMVs) are nanoscale proteoliposomes secreted from the cell envelope of all Gram-negative bacteria. Originally considered as an artifact of the cell wall, OMVs are now recognized as a general secretion system, which serves to improve the fitness of bacteria and facilitate bacterial interactions in polymicrobial communities as well as interactions between the microbe and the host. In general, OMVs are released in increased amounts from pathogenic bacteria and have been found to harbor much of the contents of the parental bacterium. They mainly encompass components of the outer membrane and the periplasm including various virulence factors such as toxins, adhesins, and immunomodulatory molecules. Numerous studies have clearly shown that the delivery of toxins and other virulence factors via OMVs essentially influences their interactions with host cells. Here, we review the OMV-mediated intracellular deployment of toxins and other virulence factors with a special focus on intestinal pathogenic Escherichia coli. Especially, OMVs ubiquitously produced and secreted by enterohemorrhagic E. coli (EHEC) appear as a highly advanced mechanism for secretion and simultaneous, coordinated and direct delivery of bacterial virulence factors into host cells. OMV-associated virulence factors are not only stabilized by the association with OMVs, but can also often target previously unknown target structures and perform novel activities. The toxins are released by OMVs in their active forms and are transported via cell sorting processes to their specific cell compartments, where they can develop their detrimental effects. OMVs can be considered as bacterial "long distance weapons" that attack host tissues and help bacterial pathogens to establish the colonization of their biological niche(s), impair host cell function, and modulate the defense of the host. Thus, OMVs contribute significantly to the virulence of the pathogenic bacteria.

• Klíčová slova
• EHEC, ETEC, intestinal pathogenic Escherichia coli, outer membrane vesicles, toxins, virulence factors,
• MeSH
• bakteriální sekreční systémy metabolismus   MeSH
• bakteriální toxiny metabolismus   MeSH
• enterohemoragická Escherichia coli metabolismus   patogenita   MeSH
• enterotoxigenní Escherichia coli metabolismus   patogenita   MeSH
• enterotoxiny metabolismus   MeSH
• faktory virulence metabolismus   MeSH
• fyziologický stres MeSH
• infekce vyvolané Escherichia coli mikrobiologie   MeSH
• lidé MeSH
• proteolipidy metabolismus   ultrastruktura   MeSH
• střeva mikrobiologie   MeSH
• transport proteinů MeSH
• virulence MeSH
• vnější bakteriální membrána metabolismus   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• bakteriální sekreční systémy MeSH
• bakteriální toxiny MeSH
• enterotoxiny MeSH
• faktory virulence MeSH
• proteolipidy MeSH
• proteoliposomes MeSH Prohlížeč

One hundred and four enterotoxin producing Escherichia coli strains of wide geographical origin were tested for the expression of curli fimbriae by transmission electronmicroscopy and by ELISA using curli-specific antibodies, as well as for the presence of curli-specific gene sequences by PCR. All isolates, irrespective of the production of the fimbriae, carried sequences specific for the structure (csgA) and for one of the regulator genes (crl) of curli expression, respectively. Curli fimbriae were detected in 56 strains (53.8 %). Thirty-six strains expressed curli only when growing at 30 degrees C, 4 isolates were weakly curliated at 37 degrees C only, while on 16 strains curli was observed at both temperatures. On isolates carrying curli at both temperatures the expression of the fimbria was significantly stronger at 30 degrees C than at 37 degrees C. Curli proficiency significantly, but not completely, correlated with the binding of the Congo Red dye. The expression of curli did not confer epithelial cell invasiveness to ETEC strains but, once expressed at 30 degrees C, it facilitated the adherence of the bacteria to plastic surfaces. Curli present in more than half of the ETEC strains and expressed preferentially at low temperatures could be a factor facilitating the environmental survival of this food- and water-borne pathogen.

• MeSH
• bakteriální adheze MeSH
• bakteriální fimbrie * ultrastruktura   MeSH
• bakteriální geny MeSH
• bakteriální proteiny analýza   MeSH
• ELISA MeSH
• enterotoxiny biosyntéza   MeSH
• Escherichia coli genetika   izolace a purifikace   ultrastruktura   MeSH
• Kongo červeň metabolismus   MeSH
• proteiny z Escherichia coli chemie   genetika   imunologie   MeSH
• regulace genové exprese u bakterií MeSH
• regulační geny MeSH
• teplota MeSH
• transmisní elektronová mikroskopie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• Crl protein, Bacteria MeSH Prohlížeč
• csgA protein, E coli MeSH Prohlížeč
• enterotoxiny MeSH
• Kongo červeň MeSH
• proteiny z Escherichia coli MeSH

Experiments were focused on diarrhea prevention in weaned piglets caused by enterotoxigenic strains of Escherichia coli (ETEC) with colonizing factor 8813. An immunization procedure consisted of intramuscular application of ETEC strain bacterin a day before weaning and a peroral administration of a live culture of nontoxic E. coli strain with the same colonizing factor on the day of weaning. In an experiment on the litter of 10 piglets (six were immunized, four were controls), their intestines were colonized by the nontoxic E. coli strain for 4-7 days (Fig. 1). The challenge peroral infection by virulent ETEC strain demonstrated the protection of immunized piglets from the disease as well as from intestinal colonization by the administered ETEC strain. The same immunization procedure was tested on three pig farms with enzootic occurrence of diarrheas in weaned piglets. On these farms, besides ETEC strain with colonizing factor 8813 (F18) ETEC strains with other colonizing factors (K88, F not specified) were found out in the weanlings - Tab. I. Immunization effect was evaluated according to the rate of mortality of immunized and nonimmunized piglets within a fortnight after weaning. Out of 222 immunized piglets on S farm (Tab. II), 25 piglets died (11.3%), out of 232 nonimmunized animals it was 39 that died (16.8%). As for T farm (Tab. III), 22 piglets (8.6%) died out of 255 immunized animals while 71 out of control 274 piglets died (25.7%). A total of 3,692 were immunized on V farm (Tab. IV). Ninety-four animals died among them (2.5%). Mortality rate in the control group of 6,301 animals was 523 piglets (8.3%).

• MeSH
• aplikace orální MeSH
• bakteriální vakcíny aplikace a dávkování   MeSH
• Escherichia coli imunologie   MeSH
• infekce vyvolané Escherichia coli prevence a kontrola   veterinární   MeSH
• injekce intramuskulární MeSH
• nemoci prasat prevence a kontrola   MeSH
• prasata MeSH
• průjem mikrobiologie   prevence a kontrola   veterinární   MeSH
• vakcíny proti Escherichia coli MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální vakcíny MeSH
• vakcíny proti Escherichia coli MeSH

The study focused on the incidence of enterotoxigenic Escherichia coli (ETEC) and verotoxigenic E. coli (VTEC) in raw milk and traditional dairy cheeses marketed in Romania, characterizing the virulence and antibiotic resistance genes of these isolates. One hundred and twenty samples of raw milk and 80 samples of unpasteurized telemy cheese were collected and cultured according to the international standard protocol. All the characteristic E. coli cultures were analyzed for the presence of STa, STb, LT, stx1, and stx2 toxicity genes. The ETEC/VTEC strains were tested for the presence of antibiotic resistance genes, such as aadA1, tetA, tetB, tetC, tetG, dfrA1, qnrA, aaC, sul1, bla SHV , bla CMY , bla TEM , and ere(A), using PCR. The results showed that 27 samples (18.62%) were positive for one of the virulence genes investigated. 48.1% (n = 13) tested positive at the genes encoding for tetracycline resistance, tetA being the most prevalent one (61.5%; n = 8). A high percent (33.3%; n = 9) revealed the beta-lactamase (bla TEM ) resistance gene, and none of the samples tested positive for bla CMY and bla SHV genes. The genes responsible for resistance to sulfonamides (sul1) and trimethoprim (dfrA1) were detected in rates of 14.8% (n = 4) and 7.4% (n = 2), respectively. E. coli is highly prevalent in raw milk and unpasteurized cheeses marketed in Romania. These strains might represent an important reservoir of resistance genes which can easily spread into other European countries, given the unique market.

• MeSH
• bakteriální geny genetika   MeSH
• bakteriální léková rezistence genetika   MeSH
• enterotoxigenní Escherichia coli účinky léků   genetika   izolace a purifikace   patogenita   MeSH
• exprese genu MeSH
• faktory virulence genetika   metabolismus   MeSH
• genotyp MeSH
• infekce vyvolané Escherichia coli mikrobiologie   přenos   veterinární   MeSH
• mikrobiální testy citlivosti MeSH
• mléko mikrobiologie   MeSH
• nemoci skotu mikrobiologie   přenos   MeSH
• polymerázová řetězová reakce MeSH
• shiga-toxigenní Escherichia coli účinky léků   genetika   izolace a purifikace   patogenita   MeSH
• skot MeSH
• sýr mikrobiologie   MeSH
• virulence MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Rumunsko MeSH
• Názvy látek
• faktory virulence MeSH

This study aimed to detect virulence factors, pathovars, and phylogenetic groups of Escherichia coli strains obtained from feces of calves with and without diarrhea up to 70 days old and to determine the association between occurrence of diarrhea, phylogenetic groups, and pathovars. Phylo-typing analysis of the 336 E. coli strains isolated from calves with Clermont method showed that 21 (6.25 %) belong to phylogroup A, 228 (67.85 %) to phylogroup B1, 2 (0.6 %) to phylogroup B2, 5 (1.49 %) to phylogroup C, 57 (16.96 %) to phylogroup E, and 3 (0.9 %) to phylogroup F. Phylogroup D was not identified and 20 strains (5.95 %) were assigned as "unknown." The distribution of phylogenetic groups among pathovars showed that NTEC belong to phylogroups B1 (17) and C (4); EPEC to phylogroups B1 (6) and E (8); STEC to phylogroups A (5), B1 (56), B2 (2), C (1), and E (15); EHEC to phylogroups B1 (95) and E (5); and ETEC to phylogroups A (3), B1 (7), and E (10). The EAST-1 strains were phylogroups A (13), B1 (47), E (19), and F (3); E. coli strains of "unknown" phylogroups belonged to pathovars EPEC (1), EHEC (2), STEC (7), and EAST-1 strains (6). ETEC was associated with diarrhea (P = 0.002). Our study did not find association between the phylogenetic background and occurrence of diarrhea (P = 0.164) but did find some relationship in phylogenetic group and pathovar. The study showed that EHEC and STEC are classified as phylogroup B1, EAST-1 phylogroup A, ETEC, and EPEC phylogroup E.

• Klíčová slova
• Calves, Escherichia coli, Pathovars, Phylogenetic group,
• MeSH
• DNA bakterií genetika   MeSH
• enteropatogenní Escherichia coli klasifikace   genetika   růst a vývoj   patogenita   MeSH
• enterotoxigenní Escherichia coli klasifikace   genetika   růst a vývoj   patogenita   MeSH
• exprese genu MeSH
• faktory virulence genetika   metabolismus   MeSH
• feces mikrobiologie   MeSH
• fylogeneze MeSH
• genotyp MeSH
• infekce vyvolané Escherichia coli diagnóza   mikrobiologie   patologie   veterinární   MeSH
• nemoci skotu diagnóza   mikrobiologie   patologie   MeSH
• polymerázová řetězová reakce MeSH
• průjem diagnóza   mikrobiologie   patologie   veterinární   MeSH
• shiga-toxigenní Escherichia coli klasifikace   genetika   růst a vývoj   patogenita   MeSH
• skot MeSH
• techniky typizace bakterií MeSH
• virulence MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH
• Názvy látek
• DNA bakterií MeSH
• faktory virulence MeSH