Nejvíce citovaný článek - PubMed ID 23760833
Human Escherichia coli strains of different geographical and time source: bacteriocin types and their gene sequences are population-specific
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
Escherichia coli strains are classified into four main phylogenetic groups (A, B1, B2, and D) and strains of these phylogroups differ in a number of characteristics. This study tested whether human fecal E. coli isolates belonging to different phylogroups differ in prevalence of bacteriocinogenic isolates and prevalence of individual bacteriocinogenic determinants. A set of 1283 fecal E. coli isolates from patients with different diseases was tested for the presence of DNA regions allowing classification into E. coli phylogroups and for the ability to produce bacteriocins (23 colicins and 7 microcins). Of the isolates tested, the most common was phylogroup B2 (38.3%) followed by phylogroups A (28.3%), D (26.3%) and B1 (7.2%). Altogether, 695 bacteriocin producers were identified representing 54.2% of all tested isolates. The highest prevalence of bacteriocin producers was found in group B2 (60.3%) and the lowest in group B1 (44.6%). Determinants encoding colicins E1, Ia, and microcin mV were most common in phylogroup A, determinants encoding microcins mM and mH47 were most common in phylogroup B2, and determinant encoding mB17 was most common in phylogroup D. The highest prevalence of bacteriocinogeny was found in phylogroup B2, suggesting that bacteriocinogeny and especially the synthesis of microcins was associated with virulent and resident E. coli strains.
- Klíčová slova
- Bacteriocin, E. coli, colicin, microcin, phylogroup.,
- MeSH
- bakteriociny metabolismus MeSH
- Escherichia coli klasifikace izolace a purifikace metabolismus patogenita MeSH
- feces mikrobiologie MeSH
- fylogeneze MeSH
- gastrointestinální trakt mikrobiologie MeSH
- koliciny metabolismus MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- bakteriociny MeSH
- koliciny MeSH
- microcin MeSH Prohlížeč
BACKGROUND: To screen whether E. coli strains encoding type 1 fimbriae, isolated from fecal microflora, produce bacteriocins more often relative to fimA-negative E. coli strains of similar origin. METHODS: PCR assays were used to detect presence of genes encoding 30 bacteriocin determinants (23 colicin- and 7 microcin-encoding genes) and 18 virulence determinants in 579 E. coli strains of human and animal origin isolated from hospitals and animal facilities in the Czech and Slovak Republic. E. coli strains were also classified into phylogroups (A, B1, B2 and D). RESULTS: fimA-negative E. coli strains (defined as those possessing none of the 18 tested virulence determinants) were compared to fimA-positive E. coli strains (possessing fimA as the only detected virulence determinant). Strains with identified bacteriocin genes were more commonly found among fimA-positive E. coli strains (35.6%) compared to fimA-negative E. coli strains (21.9%, p<0.01) and this was true for both colicin and microcin determinants (p=0.02 and p<0.01, respectively). In addition, an increased number of strains encoding colicin E1 were found among fimA-positive E. coli strains (p<0.01). CONCLUSIONS: fimA-positive E. coli strains produced bacteriocins (colicins and microcins) more often compared to fimA-negative strains of similar origin. Since type 1 fimbriae of E. coli have been shown to mediate adhesion to epithelial host cells and help colonize the intestines, bacteriocin synthesis appears to be an additional feature of colonizing E. coli strains.
- MeSH
- bakteriální fimbrie genetika MeSH
- bakteriociny genetika MeSH
- DNA bakterií genetika MeSH
- Escherichia coli genetika metabolismus MeSH
- faktory virulence genetika MeSH
- feces mikrobiologie MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- polymerázová řetězová reakce MeSH
- prasata MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Slovenská republika MeSH
- Názvy látek
- bakteriociny MeSH
- DNA bakterií MeSH
- faktory virulence MeSH
BACKGROUND: A set of 1181 E. coli strains of human fecal origin isolated in the South Moravia region of the Czech Republic was collected during the years 2007-2010. Altogether, 17 virulence determinants and 31 bacteriocin-encoding genes were tested in each of them. RESULTS: The occurrence of bacteriocin-encoding genes was found to be positively correlated with the occurrence of E. coli virulence factors. Based on the presence of virulence factors and their combinations, E. coli strains were classified as non-pathogenic E. coli (n = 399), diarrhea-associated E. coli (n = 179) and ExPEC strains (n = 603). Non-pathogenic and diarrhea-associated E. coli strains had a low frequency of bacteriocinogeny (32.6% and 36.9%, respectively). ExPEC strains encoding S-fimbriae (sfa), P-fimbriae (pap) and having genes for aerobactin biosynthesis (aer, iucC), α-hemolysis (α-hly) and cytotoxic necrosis factor (cnf1) were often bacteriocinogenic (73.8%), had a high prevalence of bacteriocin multi-producers and showed a higher frequency of genes encoding microcins H47, M, V, B17 and colicins E1, Ia and S4. CONCLUSIONS: The occurrence of bacteriocin-encoding genes and ExPEC virulence determinants correlate positively in E. coli strains of human fecal origin. Bacteriocin synthesis appears to modulate the ability of E. coli strains to reside in the human intestine and/or the virulence of the corresponding strains.
- MeSH
- bakteriální geny * MeSH
- bakteriociny genetika MeSH
- DNA bakterií chemie genetika MeSH
- Escherichia coli genetika izolace a purifikace MeSH
- faktory virulence genetika MeSH
- feces mikrobiologie MeSH
- genotyp MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- sekvenční analýza DNA MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví 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