The gut microbiota is one of the modulators influencing its host's development, metabolism, as well as immunological, psychological, and cognitive abilities. The gut microbiota consortium influences enteroendocrine regulation, neurohormonal regulation, as well as natural immune regulation. Disruptions occurring in life can lead to dysbiosis that in turn influences the host homeostasis and/or disease. Targeted modulation of microbiota composition thus appears to be an appropriate intervention strategy in cases of certain specific health problems. Here, we demonstrate that application of the nutritional supplement Imuregen, which is a natural immune booster, modulates the Bacteroidetes/Firmicutes ratio in favor of the Bacteroidetes genera and causes no pathological changes to intestinal epithelium.
Exfoliative toxin A (ETA)-coding temperate bacteriophages are leading contributors to the toxic phenotype of impetigo strains of Staphylococcus aureus. Two distinct eta gene-positive bacteriophages isolated from S. aureus strains which recently caused massive outbreaks of pemphigus neonatorum in Czech maternity hospitals were characterized. The phages, designated φB166 and φB236, were able to transfer the eta gene into a prophageless S. aureus strain which afterwards converted into an ETA producer. Complete phage genome sequences were determined, and a comparative analysis of five designed genomic regions revealed major variances between them. They differed in the genome size, number of open reading frames, genome architecture, and virion protein patterns. Their high mutual sequence similarity was detected only in the terminal regions of the genome. When compared with the so far described eta phage genomes, noticeable differences were found. Thus, both phages represent two new lineages of as yet not characterized bacteriophages of the Siphoviridae family having impact on pathogenicity of impetigo strains of S. aureus.
- MeSH
- DNA virů chemie genetika MeSH
- DNA viry genetika izolace a purifikace MeSH
- epidemický výskyt choroby MeSH
- exfoliatiny genetika MeSH
- fylogeneze MeSH
- genom virový * MeSH
- impetigo epidemiologie mikrobiologie MeSH
- infekce spojené se zdravotní péčí epidemiologie MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- novorozenec MeSH
- otevřené čtecí rámce MeSH
- polymorfismus délky restrikčních fragmentů MeSH
- pořadí genů MeSH
- porodnice MeSH
- přenos genů horizontální MeSH
- profágy klasifikace genetika izolace a purifikace MeSH
- sekvenční analýza DNA MeSH
- sekvenční homologie MeSH
- shluková analýza MeSH
- stafylokokové bakteriofágy klasifikace genetika izolace a purifikace MeSH
- stafylokokové infekce epidemiologie mikrobiologie MeSH
- Staphylococcus aureus izolace a purifikace virologie MeSH
- syntenie MeSH
- transdukce genetická MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Natural variation in the presence or the absence of STM0517-0529 genes allowing allantoin utilisation has been described in field isolates of the multidrug resistant Salmonella enterica serovar Typhimurium belonging to the phage type DT104. Interestingly, S. enterica subspecies enterica serovar Typhimurium DT104 is quite frequent in pigs and cattle, but rarely present in egg-laying hens. Taking into account the different mode of allantoin metabolism in birds and mammals, we were interested in whether the absence of STM0517-0529 genes may disable this clone in poultry colonisation. We have therefore constructed the allB (also designated as STM0523) mutants in S. enterica subspecies enterica serovar Typhimurium and S. enterica subspecies enterica serovar Enteritidis, and with these, we infected mice, newly hatched chickens and adult egg-laying hens to show that the defect in allantoin utilisation does not influence S. enterica virulence for mice or adult hens, but slightly decreases virulence of S. enterica for chickens. The decrease in virulence of the allB mutant was relatively minor as it could be observed only after a mixed infection model, consistent with a lower prevalence, but not a total absence of such clones in poultry flocks.
- MeSH
- alantoin metabolismus MeSH
- drůbež MeSH
- kyselina močová metabolismus MeSH
- mnohočetná bakteriální léková rezistence MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- nemoci drůbeže mikrobiologie patologie MeSH
- Salmonella enteritidis genetika metabolismus patogenita MeSH
- Salmonella typhimurium genetika metabolismus patogenita MeSH
- salmonelová infekce u zvířat mikrobiologie patologie MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH