ETEC
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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.
- 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
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.
- 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
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
The effects of live yeast Saccharomyces cerevisiae (strain CNCM I-4407, 10(10) cfu/g; Actisaf; Lesaffre Feed Additives, Marcq-en-Baroeul, France) on the severity of diarrhea, immune response, and growth performance in weaned piglets orally challenged with enterotoxigenic Escherichia coli (ETEC) strain O149:K88 were investigated. Live yeast was fed to sows and their piglets in the late gestation, suckling, and postweaning periods. Sows were fed a basal diet without (Control; n = 2) or with (Supplemented; n = 2) 1 g/kg of live yeast from d 94 of gestation and during lactation until weaning of the piglets (d 28). Suckling piglets of the supplemented sows were orally treated with 1 g of live yeast in porridge carrier 3 times a week until weaning. Weaned piglets were fed a basal starter diet without (Control; n = 19) or with (Supplemented; n = 15) 5 g of live yeast/kg feed for 2 wk. Significantly lower daily diarrhea scores (P < 0.05), duration of diarrhea (P < 0.01), and shedding of pathogenic ETEC bacteria (P < 0.05) in feces was detected in the supplemented piglets. Administration of live yeast significantly increased (P < 0.05) IgA levels in the serum of piglets. Evidence indicates that decreased infection-related stress and severity of diarrhea in yeast-fed weaned piglets positively affected their growth capacity in the postweaning period (P < 0.05). The results suggest that dietary supplementation with live yeast S. cerevisiae to sows and piglets in the late gestation, suckling, and postweaning periods can be useful in the reduction of the duration and severity of postweaning diarrhea caused by ETEC.
- MeSH
- dieta veterinární MeSH
- enterotoxigenní Escherichia coli klasifikace MeSH
- fyziologie výživy v mateřství MeSH
- fyziologie výživy zvířat MeSH
- imunoglobulin A krev MeSH
- infekce vyvolané Escherichia coli prevence a kontrola veterinární MeSH
- krmivo pro zvířata MeSH
- nemoci prasat etiologie prevence a kontrola MeSH
- prasata růst a vývoj imunologie MeSH
- průjem etiologie prevence a kontrola veterinární MeSH
- Saccharomyces cerevisiae * MeSH
- těhotenství MeSH
- zvířata MeSH
- Check Tag
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky kontrolované MeSH
- práce podpořená grantem MeSH
Poruchy vyprazdňování stolice patří bezesporu k nejčastějším problémům, které postihují cestovatele. Tzv. cestovatelský průjem je vůbec nejčastější poruchou zdraví u osob cestujících do zahraničí. Postihuje 30–80 % cestovatelů během pobytu v rozvojové zemi oblastí teplého klimatu s nedostatečnou úrovní hygieny. Naopak zácpou, na které se nejčastěji podílí cestovní stres, nepravidelné stravování či zadržování stolice při nevyhovujících hygienických podmínkách, trpí 20–30 % cestovatelů. Přestože obecně nejsou zácpa a průjem život ohrožující a nevyžadují zpravidla hospitalizaci, stávají se velmi často značnou komplikací znepříjemňující cestování.
Defecation disorders are undoubtedly among the most common issues affecting travellers. So-called traveller's diarrhoea is the most frequent ailment in people travelling abroad. It affects 30 to 80% of travellers during their stay in a developing country in a region with warm climate and with insufficient standards of hygiene. By contrast, 20 to 30% of travellers suffer from constipation that is most commonly a result of travelling stress, irregular meals, or retaining stools in a setting of inadequate hygiene conditions. Although constipation and diarrhoea generally are not life threatening and do not usually require hospitalization, they very often are a major complication making travelling uncomfortable.
Between 2005 and 2009, a total of 800 Escherichia coli strains isolated from piglets with diarrhea were tested for the presence of enteroaggregative heat-stable enterotoxin EAST1, heat-labile (LT) and heat-stable enterotoxins (STa) and shigatoxin (Stx2e) by PCR with the purpose of investigating the present distribution of virulence factors on swine farms in the Czech Republic. The isolates were analyzed for their O-serogroup, fimbrial (K88, K99, 987P, F41, F18) and nonfimbrial adhesins (adhesin involved in diffuse adherence AIDA and porcine attaching and effacing-associated factor PAA). The detection rates of ETEC and STEC isolates were 36.5% and 7.75%, respectively, which implies that ETEC play the major role in E. coli infections in Czech herds. Generally, the most common serotype was O149:K88 which possessed genetic determinants for LT and EAST1. None of the tested E. coli isolates was positive for genes K99, 987P and F41. It was shown that out of 800 E. coli strains isolated from pigs, 277 were EAST1 positive and 74% from the latter were identified as ETEC. Of the fimbrial adhesins, K88 and F18 were commonly detected. Over 80% of K88/EAST1 positive strains possessed the gene for paa. We detected no EAE isolate positive for fimbrial adhesins or PAA and AIDA. The AIDA was more often associated with F18 than with K88. The gene astA was also identified among E. coli isolates of non-diarrheic piglets. We tested rectal swab samples collected from apparently healthy piglets on three farms. On all farms, E. coli astA positive strains (26.66%, 90.00% and 46.66% astA positive animals) were isolated. Our results showed a significantly higher prevalence of astA positive E. coli isolates among apparently healthy piglets in comparison with diarrheic piglets. The question remains as to what is the role of the astA gene in the pathogenesis of porcine colibacillosis and as a virulence factor.
- MeSH
- bakteriální adheze fyziologie MeSH
- bakteriální adheziny genetika metabolismus MeSH
- bakteriální fimbrie genetika metabolismus MeSH
- enterotoxigenní Escherichia coli izolace a purifikace MeSH
- enterotoxiny izolace a purifikace metabolismus MeSH
- Escherichia coli genetika izolace a purifikace metabolismus patogenita MeSH
- faktory virulence metabolismus MeSH
- feces mikrobiologie MeSH
- infekce vyvolané Escherichia coli patologie veterinární MeSH
- nemoci prasat epidemiologie mikrobiologie MeSH
- polymerázová řetězová reakce veterinární MeSH
- prasata MeSH
- prevalence MeSH
- proteiny z Escherichia coli genetika metabolismus MeSH
- průjem mikrobiologie patologie veterinární MeSH
- shiga toxin metabolismus MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika 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
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.
- 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
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.
- 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
- 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
