Escherichia albertii is a recently discovered species with a limited number of well characterized strains. The aim of this study was to characterize four of the E. albertii strains, which were among 41 identified Escherichia strains isolated from the feces of living animals on James Ross Island, Antarctica, and Isla Magdalena, Patagonia. Sequencing of 16S rDNA, automated ribotyping, and rep-PCR were used to identify the four E. albertii isolates. Phylogenetic analyses based on multi-locus sequence typing showed these isolates to be genetically most similar to the members of E. albertii phylogroup G3. These isolates encoded several virulence factors including those, which are characteristic of E. albertii (cytolethal distending toxin and intimin) as well as bacteriocin determinants that typically have a very low prevalence in E. coli strains (D, E7). Moreover, E. albertii protein extracts caused cell cycle arrest in human cell line A375, probably because of cytolethal distending toxin activity.

• Klíčová slova
• Antarctica, Escherichia albertii, bacteriocins, cytolethal distending toxin,
• MeSH
• Charadriiformes mikrobiologie   MeSH
• Escherichia genetika   izolace a purifikace   metabolismus   MeSH
• feces mikrobiologie   MeSH
• multilokusová sekvenční typizace veterinární   MeSH
• polymerázová řetězová reakce veterinární   MeSH
• pulzní gelová elektroforéza veterinární   MeSH
• ribotypizace veterinární   MeSH
• RNA ribozomální 16S genetika   MeSH
• Spheniscidae mikrobiologie   MeSH
• tuleňovití mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Antarktida MeSH
• Chile MeSH
• Názvy látek
• RNA ribozomální 16S MeSH

BACKGROUND: The study used a set of 407 human extraintestinal pathogenic E. coli strains (ExPEC) isolated from (1) skin and soft tissue infections, (2) respiratory infections, (3) intra-abdominal infections, and (4) genital smears. The set was tested for bacteriocin production, for prevalence of bacteriocin and virulence determinants, and for phylogenetic typing. Results obtained from the group of ExPEC strains were compared to data from our previously published analyses of 1283 fecal commensal E. coli strains. RESULTS: The frequency of bacteriocinogeny was significantly higher in the set of ExPEC strains (63.1 %), compared to fecal E. coli (54.2 %; p < 0.01). Microcin producers and microcin determinants dominated in ExPEC strains, while colicin producers and colicin determinants were more frequent in fecal E. coli (p < 0.01). Higher production of microcin M and lower production of microcin B17, colicin Ib, and Js was detected in the set of ExPEC strains. ExPEC strains had a significantly higher prevalence of phylogenetic group B2 (52.6 %) compared to fecal E. coli strains (38.3 %; p < 0.01). CONCLUSIONS: Human ExPEC strains were shown to differ from human fecal strains in a number of parameters including bacteriocin production, prevalence of several bacteriocin and virulence determinants, and prevalence of phylogenetic groups. Differences in these parameters were also identified within subgroups of ExPEC strains of diverse origin. While some microcin determinants (mM, mH47) were associated with virulent strains, other bacteriocin types (mB17, Ib, and Js) were associated with fecal flora.

• Klíčová slova
• Bacteriocinogeny, Colicin, Escherichia coli, ExPEC, Microcin, Virulence factor,
• MeSH
• bakteriální geny MeSH
• bakteriociny klasifikace   genetika   metabolismus   MeSH
• dítě MeSH
• DNA bakterií genetika   MeSH
• dospělí MeSH
• dýchací soustava mikrobiologie   MeSH
• extraintestinální patogenní Escherichia coli genetika   izolace a purifikace   metabolismus   patogenita   MeSH
• faktory virulence genetika   metabolismus   MeSH
• feces mikrobiologie   MeSH
• fylogeneze * MeSH
• gastrointestinální trakt mikrobiologie   MeSH
• infekce reprodukčního traktu mikrobiologie   MeSH
• infekce vyvolané Escherichia coli mikrobiologie   MeSH
• kojenec MeSH
• koliciny metabolismus   MeSH
• kůže mikrobiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• předškolní dítě MeSH
• prevalence * MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• bakteriociny MeSH
• DNA bakterií MeSH
• faktory virulence MeSH
• koliciny MeSH
• microcin MeSH Prohlížeč

A novel colicin type, designated colicin Fy, was found to be encoded and produced by the strain Yersinia frederiksenii Y27601. Colicin Fy was active against both pathogenic and nonpathogenic strains of the genus Yersinia. Plasmid YF27601 (5,574 bp) of Y. frederiksenii Y27601 was completely sequenced. The colicin Fy activity gene (cfyA) and the colicin Fy immunity gene (cfyI) were identified. The deduced amino acid sequence of colicin Fy was very similar in its C-terminal pore-forming domain to colicin Ib (69% identity in the last 178 amino acid residues), indicating pore forming as its lethal mode of action. Transposon mutagenesis of the colicin Fy-susceptible strain Yersinia kristensenii Y276 revealed the yiuR gene (ykris001_4440), which encodes the YiuR outer membrane protein with unknown function, as the colicin Fy receptor molecule. Introduction of the yiuR gene into the colicin Fy-resistant strain Y. kristensenii Y104 restored its susceptibility to colicin Fy. In contrast, the colicin Fy-resistant strain Escherichia coli TOP10F' acquired susceptibility to colicin Fy only when both the yiuR and tonB genes from Y. kristensenii Y276 were introduced. Similarities between colicins Fy and Ib, similarities between the Cir and YiuR receptors, and the detected partial cross-immunity of colicin Fy and colicin Ib producers suggest a common evolutionary origin of the colicin Fy-YiuR and colicin Ib-Cir systems.

• MeSH
• bakteriální chromozomy genetika   MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• buněčná membrána fyziologie   MeSH
• Escherichia coli genetika   metabolismus   MeSH
• fylogeneze MeSH
• genotyp MeSH
• klonování DNA MeSH
• koliciny metabolismus   farmakologie   MeSH
• membránové proteiny genetika   metabolismus   MeSH
• molekulární sekvence - údaje MeSH
• plazmidy genetika   MeSH
• regulace genové exprese u bakterií fyziologie   MeSH
• sekvence aminokyselin MeSH
• Yersinia účinky léků   genetika   metabolismus   patogenita   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• koliciny MeSH
• membránové proteiny MeSH
• tonB protein, Bacteria MeSH Prohlížeč

The strain Escherichia coli Nissle 1917 (EcN) is widely used as an efficient probiotic in therapy and prevention of human infectious diseases, especially of the intestinal system. Concurrently, small adult pigs are being used as experimental omnivore models to study human gastrointestinal functions. EcN bacteria were applied to 6 adult healthy female pigs in a 2-week trial. 6 Control animals remained untreated. Altogether, 164 and 149 bacterial strains were isolated from smear samples taken from gastrointestinal mucosa in the experimental and control group, respectively. Each individual E. coli strain was then tested for the presence of 29 bacteriocin-encoding determinants as well as for DNA markers of A, B1, B2 and D phylogenetic groups. A profound reduction of E. coli genetic variance (from 32 variants to 13 ones, P = 0.0006) was found in the experimental group, accompanied by a lower incidence of bacteriocin producers in the experimental group when compared to control (21.3 and 34.9%, respectively; P = 0.007) and by changes in the incidence of individual bacteriocin types. The experimental administration of EcN strain was not sufficient for stable colonization of porcine gut, but induced significant changes in the enterobacterial microbiota.

• MeSH
• bakteriální geny MeSH
• bakteriociny genetika   MeSH
• Escherichia coli klasifikace   izolace a purifikace   MeSH
• fylogeneze MeSH
• genetická variace MeSH
• molekulární typizace MeSH
• prasata MeSH
• probiotika aplikace a dávkování   MeSH
• společenstvo * MeSH
• střevní sliznice mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriociny MeSH

BACKGROUND: Bacteriocin production is an important characteristic of E. coli strains of human origin. To date, 26 colicin and 9 microcin types have been analyzed on a molecular level allowing molecular detection of the corresponding genes. The production incidence of 29 bacteriocin types and E. coli phylogroups were tested in a set of 361 E. coli strains isolated from human urinary tract infections (UTI) and in 411 control strains isolated from feces of patients without bacterial gut infection. RESULTS: Production of 17 and 20 individual bacteriocin types was found in the UTI and control strains, respectively. Microcin H47 encoding determinants were found more often among UTI strains compared to controls (37.9% and 27.0% respectively, p = 0.02) and strains producing microcin H47 belonged predominantly to phylogroup B2 when compared to other bacteriocin producers (67.4% and 36.7%, respectively; p < 0.0001). Producers of 3 or more identified bacteriocin types were more common in the UTI group (20.0% compared to 12.4% in controls, p = 0.03). In the UTI strains, there was a markedly higher number of those producing colicin E1 compared to controls (22.1% to 10.2%, respectively, p = 0.0008). Moreover, colicin E1 production was more common in the UTI bacteriocinogenic strains with multi-producer capabilities. As shown by Southern blotting, pColE1 DNA was not recognized by the ColIa probe and vice versa suggesting that pColE1 was independently associated with pColIa in UTI strains. CONCLUSION: E. coli strains isolated from human urinary tract infections showed increased incidence of microcin H47 and colicin E1 production, respectively. Moreover, colicin E1 itself appears to be a potentially important virulence factor of certain uropathogenic E. coli strains.

• MeSH
• bakteriociny biosyntéza   genetika   MeSH
• Escherichia coli genetika   izolace a purifikace   metabolismus   MeSH
• faktory virulence genetika   metabolismus   MeSH
• feces mikrobiologie   MeSH
• infekce močového ústrojí mikrobiologie   MeSH
• infekce vyvolané Escherichia coli mikrobiologie   MeSH
• koliciny genetika   metabolismus   MeSH
• lidé MeSH
• uropatogenní Escherichia coli genetika   izolace a purifikace   metabolismus   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriociny MeSH
• faktory virulence MeSH
• koliciny MeSH