Taylorella equigenitalis is the causative agent of sexually transmitted contagious equine metritis. Infections manifest as cervicitis, vaginitis and endometritis and cause temporary infertility and miscarriages of mares. While previous studies have analyzed this organism for various parameters, the evolutionary dynamics of this pathogen, including the emergence of antibiotic resistance, remains unresolved. The aim of this study was to isolate contemporary strains, determine their genome sequences, evaluate their antibiotic resistance and compare them with other strains. We determined nine complete whole genome sequences of T. equigenitalis strains, mainly from samples collected from Kladruber horses in the Czech Republic. While T. equigenitalis strains from Kladruby isolated between 1982 and 2018 were inhibited by streptomycin, contemporary strains were found to be resistant to streptomycin, suggesting the recent emergence of this mutation. In addition, we used the collection dates of Kladruber horse strains to estimate the genome substitution rate, which resulted in a scaled mean evolutionary rate of 6.9×10-7 substitutions per site per year. Analysis with other available T. equigenitalis genome sequences (n = 18) revealed similarity of the Czech T. equigenitalis genomes with the Austrian T. equigenitalis genome, and molecular dating suggested a common ancestor of all analyzed T. equigenitalis strains from 1.5-2.6 thousand years ago, dating to the first centuries A.D. Our study revealed a recently emerged streptomycin resistance in T. equigenitalis strains from Kladruber horses, emphasizing the need for antibiotic surveillance and alternative treatments. Additionally, our findings provided insights into the pathogen's evolution rate, which is important for understanding its evolution and preparing preventive strategies.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- fylogeneze MeSH
- genom bakteriální * genetika MeSH
- koně mikrobiologie MeSH
- molekulární evoluce MeSH
- nemoci koní * mikrobiologie MeSH
- sekvenování celého genomu * MeSH
- Taylorella equigenitalis * genetika MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Fonticins are phage tail-like bacteriocins produced by the Gram-negative bacterium Pragia fontium from the family Budviciaceae. This bacterium produces contractile-type particles that adsorb on the surface of sensitive bacteria and penetrate the cell wall, probably during contraction, in a way similar to the type VI secretion system. We characterized the pore-forming activity of fonticins using both living cells and in vitro model membranes. Using a potassium leakage assay, we show that fonticins are able to permeabilize sensitive cells. On black lipid membranes, single-pore conductance is about 0.78 nS in 1 M NaCl and appears to be linearly dependent on the increasing molar strength of NaCl solution, which is a property of considerably large pores. In agreement with these findings, fonticins are not ion selective for Na+, K+, and Cl-. Polyethylene glycol 3350 (PEG 3350) molecules of about 3.5 nm in diameter can enter the fonticin pore lumen, whereas the larger molecules cannot pass the pore. The size of fonticin pores was confirmed by transmission electron microscopy. The terminal membrane-piercing complex of the fonticin tube probably creates a selective barrier restricting passage of macromolecules. IMPORTANCE Phage tail-like bacteriocins are now the subject of research as potent antibacterial agents due to their narrow host specificity and single-hit mode of action. In this work, we focused on the structure and mode of action of fonticins. According to some theories, related particles were initially adapted for passage of double-stranded DNA (dsDNA) molecules, but fonticins changed their function during the evolution; they are able to form large pores through the bacterial envelope of Gram-negative bacteria. As various pore-forming proteins are extensively used for nanopore sequencing and stochastic sensing, we decided to investigate the pore-forming properties of fonticin protein complexes on artificial lipid membranes. Our research revealed remarkable structural properties of these particles that may have a potential application as a nanodevice.
The complete genome sequences of five Escherichia coli strains with probiotic attributes were determined, including strain A0 34/86, a component of the probiotic product Colinfant New Born, and strains H22, 582, B771, and B1172 with published probiotic potential. The size of sequenced genomes ranged from 5,092 to 5,408 kb.
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Pathogenic strains of Escherichia coli have been clearly identified as the causative agents of extraintestinal and diarrheal infections; however, the etiopathogenic role of E. coli in other conditions, including colorectal cancer, remains unclear. METHODS: This study aimed to characterize mucosal E. coli isolates (n = 246) from 61 neoplasia patients and 20 healthy controls for the presence of 35 genetic determinants encoding known virulence factors. RESULTS: Virulence determinants encoding invasin (ibeA), siderophore receptor (iroN), S-fimbriae (sfa), and genotoxin (usp) were more prevalent among E. coli isolated from patients with neoplasia compared to the control group (p < 0.05). In addition, the prevalence of these virulence determinants was increased in more advanced neoplasia stages (padj < 0.0125). Compared to patients with advanced colorectal adenoma and carcinoma, the ibeA gene was rarely found in the control group and among patients with non-advanced adenoma (p < 0.05), indicating its potential as the advanced-neoplasia biomarker. Patients with neoplasia frequently had E. coli strains with at least one of the abovementioned virulence factors, whereby specific combinations of these virulence factors were found. DISCUSSION: These findings suggest that E. coli strains isolated from patients with colorectal neoplasia possess several virulence factors, which could contribute to the development of neoplastic processes in the large intestine.
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: The emergence and spread of antibiotic resistance among pathogenic bacteria drives the search for alternative antimicrobial therapies. Bacteriocins represent a potential alternative to antibiotic treatment. In contrast to antibiotics, bacteriocins are peptides or proteins that have relatively narrow spectra of antibacterial activities and are produced by a wide range of bacterial species. Bacteriocins of Escherichia coli are historically classified as microcins and colicins, and, until now, more than 30 different bacteriocin types have been identified and characterized. AREAS COVERED: We performed bibliographical searches of online databases to review the literature regarding bacteriocins produced by E. coli with respect to their occurrence, bacteriocin role in bacterial colonization and pathogenicity, and application of their antimicrobial effect. EXPERT OPINION: The potential use of bacteriocins for applications in human and animal medicine and the food industry includes (i) the use of bacteriocin-producing probiotic strains, (ii) recombinant production in plants and application in food, and (iii) application of purified bacteriocins.
- MeSH
- antibakteriální látky biosyntéza izolace a purifikace farmakologie MeSH
- bakteriociny biosyntéza izolace a purifikace farmakologie MeSH
- Escherichia coli metabolismus MeSH
- koliciny biosyntéza izolace a purifikace farmakologie MeSH
- lidé MeSH
- probiotika farmakologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy 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.
- 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
Common variable immunodeficiency (CVID) is a clinically and genetically heterogeneous disorder with inadequate antibody responses and low levels of immunoglobulins including IgA that is involved in the maintenance of the intestinal homeostasis. In this study, we analyzed the taxonomical and functional metagenome of the fecal microbiota and stool metabolome in a cohort of six CVID patients without gastroenterological symptomatology and their healthy housemates. The fecal microbiome of CVID patients contained higher numbers of bacterial species and altered abundance of thirty-four species. Hungatella hathewayi was frequent in CVID microbiome and absent in controls. Moreover, the CVID metagenome was enriched for low-abundance genes likely encoding nonessential functions, such as bacterial motility and metabolism of aromatic compounds. Metabolomics revealed dysregulation in several metabolic pathways, mostly associated with decreased levels of adenosine in CVID patients. Identified features have been consistently associated with CVID diagnosis across the patients with various immunological characteristics, length of treatment, and age. Taken together, this initial study revealed expansion of bacterial diversity in the host immunodeficient conditions and suggested several bacterial species and metabolites, which have potential to be diagnostic and/or prognostic CVID markers in the future.
- MeSH
- adenosin metabolismus MeSH
- běžná variabilní imunodeficience genetika mikrobiologie MeSH
- biodiverzita MeSH
- Clostridiaceae fyziologie MeSH
- dysbióza genetika mikrobiologie MeSH
- feces mikrobiologie MeSH
- homeostáza MeSH
- lidé MeSH
- metabolomika MeSH
- metagenom MeSH
- RNA ribozomální 16S genetika MeSH
- střevní mikroflóra genetika MeSH
- výpočetní biologie metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Colinfant New Born (CNB) is an orally administered probiotic preparation containing the Escherichia coli strain A0 34/86, which is specially marketed for use in newborns and infants. Although the impact of different probiotics on the composition of the human gut microbiota has been previously described, the effects of E. coli probiotic consumption during infancy on the development of intestinal microbiota are not known. The effect of oral administration of CNB on the Enterobacteriaceae population was mapped using 16S rRNA gene sequencing in DNA samples isolated from the stools of one infant collected at 177 different time points during the first year of life. E. coli strains turnover was analyzed based on the detection of 26 genetic determinants, phylogroups, and pulsed-field gel electrophoresis (PFGE) analysis. Administration of CNB during the second and third month of life introduced the Escherichia genus to the infant's intestinal tract, and Escherichia became dominant among the Enterobacteriaceae family (p < 0.01). Genetic determinants, typical for probiotic E. coli A0 34/86 strain, were detected on the first day after application of CNB and persisted all year. In addition, nine transient E. coli strains were identified; these strains harbored different genetic determinants and showed different PFGE profiles. Transient strains were detected from 2 to 24 days in the stool samples. The first Escherichia colonizer originated from the application of the CNB probiotic preparation. Probiotic E. coli A0 34/86 successfully colonized the intestinal tract of an infant and became resident during the first year of life.
- MeSH
- Escherichia coli * MeSH
- kojenec MeSH
- lidé MeSH
- novorozenec MeSH
- probiotika aplikace a dávkování MeSH
- střeva mikrobiologie MeSH
- střevní mikroflóra * MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- novorozenec MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Optimal therapy for colorectal carcinoma (CRC), a frequently diagnosed malignancy, does not exist. Some of colicins and microcins, ribosomally synthesized peptides by gramnegative bacteria, have shown significant biological activity specifically against different cancer cells in vitro and in vivo conditions. The aim of this prospective study was to evaluate natural colicin and microcin production by large intestinal mucosal bacteria in each stage of colorectal neoplasia and in those with a history of colorectal neoplasia. METHODS: A total of 21 patients with non-advanced adenoma (non-a-A; 16/21 with current and 5/21 with history of non-a-A), 20 patients with advanced colorectal adenoma (a-A; 11/20 with current and 9/20 with history of a-A), 22 individuals with CRC (9/22 with current and 13/22 with history of CRC) and 20 controls were enrolled. Mucosal biopsies from the caecum, transverse colon and the rectum were taken during colonoscopy in each individual. Microbiological culture followed. Production of colicins and microcins was evaluated by PCR methods. RESULTS: A total of 239 mucosal biopsies were taken. Production of colicins and microcins was significantly more frequent in individuals with non-a-A, a-A and CRC compared to controls. No significant difference in colicin and microcin production was found between patients with current and previous non-a-A, a-A and CRC. Significantly more frequent production of colicins was observed in men compared to women at the stage of colorectal carcinoma. A later onset of increased production of microcins during the adenoma-carcinoma sequence has been observed in males compared to females. CONCLUSIONS: Strains isolated from large intestinal mucosa in patients with colorectal neoplasia produce colicins and microcins more frequently compared to controls. Bacteriocin production does not differ between patients with current and previous colorectal neoplasia. Fundamental differences in bacteriocin production have been confirmed between males and females.
