- MeSH
- biologické jevy * MeSH
- mikrobiologie MeSH
- publikace * MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- Bacteria * MeSH
- mikrobiologie MeSH
- půdní mikrobiologie * MeSH
- Publikační typ
- časopisecké články MeSH
Euglena gracilis is a unicellular photosynthetic eukaryotic flagellate of the Discoba supergroup, which also encompasses Kinetoplastida and Diplonema. Plastids have green algal origin and are secondarily acquired. The nuclear genome is extremely large and many genes suggest multiple endosymbiotic/gene transfer events, i.e. derivation from prokaryotes of various lineages. E. gracilis is remarkably robust and can proliferate in environments contaminated with heavy metals and acids. Extraordinary metabolic plasticity and a mixotrophic lifestyle confers an ability to thrive in a broad range of environments, as well as facilitating production of many novel metabolites, making Euglena of considerable biotechnological importance.
- Klíčová slova
- Euglena, evolution, genome, protists, secondary endosymbiosis,
- MeSH
- Chlorophyta * MeSH
- Euglena gracilis * genetika metabolismus MeSH
- fotosyntéza MeSH
- plastidy genetika metabolismus MeSH
- symbióza MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The existence of programmed cell death in Saccharomyces cerevisiae has been reported for many years. Glucose induces the death of S. cerevisiae in the absence of additional nutrients within a few hours, and the absence of active potassium uptake makes cells highly sensitive to this process. S. cerevisiae cells possess two transporters, Trk1 and Trk2, which ensure a high intracellular concentration of potassium, necessary for many physiological processes. Trk1 is the major system responsible for potassium acquisition in growing and dividing cells. The contribution of Trk2 to potassium uptake in growing cells is almost negligible, but Trk2 becomes crucial for stationary cells for their survival of some stresses, e.g. anhydrobiosis. As a new finding, we show that both Trk systems contribute to the relative thermotolerance of S. cerevisiae BY4741. Our results also demonstrate that Trk2 is much more important for the cell survival of glucose-induced cell death than Trk1, and that stationary cells deficient in active potassium uptake lose their ATP stocks more rapidly than cells with functional Trk systems. This is probably due to the upregulated activity of plasma-membrane Pma1 H+-ATPase, and consequently, it is the reason why these cells die earlier than cells with functional active potassium uptake.
- Klíčová slova
- ATP content, GICD, Saccharomyces cerevisiae, potassium uptake, stationary cells, thermotolerance,
- MeSH
- buněčná smrt MeSH
- draslík metabolismus MeSH
- glukosa metabolismus MeSH
- mikrobiální viabilita MeSH
- proteiny přenášející kationty genetika metabolismus MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae cytologie růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- draslík MeSH
- glukosa MeSH
- proteiny přenášející kationty MeSH
- Saccharomyces cerevisiae - proteiny MeSH
- TRK1 protein, S cerevisiae MeSH Prohlížeč
- TRK2 protein, S cerevisiae MeSH Prohlížeč
Lyme borreliosis is a vector-borne infection caused by bacteria under the Borrelia burgdorferi sensu lato complex, both in Europe and North America. Differential gene expression at different times throughout its infectious cycle allows the spirochete to survive very diverse environments within different mammalian hosts as well as the tick vector. To date, the vast majority of data about spirochetal proteins and their functions are from genetic studies carried out on North American strains of a single species, i.e. B. burgdorferi sensu stricto. The whole-genome sequences recently obtained for several European species/strains make it feasible to adapt and use genetic techniques to study inherent differences between them. This review highlights the crucial need to undertake independent studies of genospecies within Europe, given their varying genetic content and pathogenic potential, and differences in clinical manifestation.
- Klíčová slova
- Borrelia diversity, Europe vs North America, Lyme borreliosis, genetic manipulations, tick,
- MeSH
- biodiverzita MeSH
- Borrelia burgdorferi genetika patogenita MeSH
- DNA bakterií genetika MeSH
- faktory virulence genetika MeSH
- genetická variace MeSH
- genotyp MeSH
- interakce hostitele a patogenu MeSH
- klíšťata mikrobiologie MeSH
- lidé MeSH
- lymeská nemoc epidemiologie mikrobiologie přenos MeSH
- regulace genové exprese u bakterií * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Geografické názvy
- Evropa MeSH
- Severní Amerika MeSH
- Názvy látek
- DNA bakterií MeSH
- faktory virulence MeSH
Exposure to stressors can negatively impact the mammalian gastrointestinal microbiome (GIM). Here, we used 454 pyrosequencing of 16S rRNA bacterial gene amplicons to evaluate the impact of physiological stress, as evidenced by faecal glucocorticoid metabolites (FGCM; ng/g), on the GIM composition of free-ranging western lowland gorillas (Gorilla gorilla gorilla). Although we found no relationship between GIM alpha diversity (H) and FGCM levels, we observed a significant relationship between the relative abundances of particular bacterial taxa and FGCM levels. Specifically, members of the family Anaerolineaceae (ρ=0.4, FDR q=0.01), genus Clostridium cluster XIVb (ρ=0.35, FDR q=0.02) and genus Oscillibacter (ρ=0.35, FDR q=0.02) were positively correlated with FGCM levels. Thus, while exposure to stressors appears to be associated with minor changes in the gorilla GIM, the consequences of these changes are unknown. Our results may have implications for conservation biology as well as for our overall understanding of factors influencing the non-human primate GIM.
- Klíčová slova
- bacteria, faecal glucocorticoid metabolites, gastrointestinal microbiome, stress, western lowland gorilla,
- MeSH
- Bacteria klasifikace genetika MeSH
- DNA bakterií MeSH
- feces chemie mikrobiologie MeSH
- fyziologický stres * MeSH
- glukokortikoidy analýza MeSH
- Gorilla gorilla mikrobiologie fyziologie MeSH
- RNA ribozomální 16S MeSH
- sekvenční analýza DNA MeSH
- statistické modely MeSH
- střevní mikroflóra fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- DNA bakterií MeSH
- glukokortikoidy MeSH
- RNA ribozomální 16S MeSH
Pseudomonas aeruginosa causes chronic lung infections in people with cystic fibrosis (CF) and acute opportunistic infections in people without CF. Forty-two P. aeruginosa strains from a range of clinical and environmental sources were collated into a single reference strain panel to harmonise research on this diverse opportunistic pathogen. To facilitate further harmonized and comparable research on P. aeruginosa, we characterized the panel strains for growth rates, motility, virulence in the Galleria mellonella infection model, pyocyanin and alginate production, mucoid phenotype, LPS pattern, biofilm formation, urease activity, and antimicrobial and phage susceptibilities. Phenotypic diversity across the P. aeruginosa panel was apparent for all phenotypes examined, agreeing with the marked variability seen in this species. However, except for growth rate, the phenotypic diversity among strains from CF versus non-CF sources was comparable. CF strains were less virulent in the G. mellonella model than non-CF strains (P = 0.037). Transmissible CF strains generally lacked O-antigen, produced less pyocyanin and had low virulence in G. mellonella. Furthermore, in the three sets of sequential CF strains, virulence, O-antigen expression and pyocyanin production were higher in the earlier isolate compared to the isolate obtained later in infection. Overall, this full phenotypic characterization of the defined panel of P. aeruginosa strains increases our understanding of the virulence and pathogenesis of P. aeruginosa and may provide a valuable resource for the testing of novel therapies against this problematic pathogen.
- MeSH
- analýza přežití MeSH
- cystická fibróza komplikace MeSH
- fenotyp * MeSH
- LD50 MeSH
- Lepidoptera mikrobiologie MeSH
- lidé MeSH
- lokomoce MeSH
- mikrobiologie životního prostředí * MeSH
- modely nemocí na zvířatech MeSH
- pseudomonádové infekce mikrobiologie MeSH
- Pseudomonas aeruginosa klasifikace izolace a purifikace patogenita fyziologie MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
Our basic cell biology research was aimed at investigating the effect on eukaryotic cells of the sudden loss of the F-actin cytoskeleton. Cells treated with latrunculin A (LA) in yeast extract peptone dextrose (YEPD) medium were examined using phase-contrast and fluorescent microscopy, freeze-substitution, transmission and scanning electron microscopy, counted using a Bürker chamber and their absorbance measured. The cells responded to the presence of LA, an F-actin inhibitor, with the disappearance of actin patches, actin cables and actin rings. This resulted in the formation of larger spherical cells with irregular morphology in the cell walls and ultrastructural disorder of the cell organelles and secretory vesicles. Instead of buds, LA-inhibited cells formed only 'table-mountain-like' wide flattened swellings without apical growth with a thinner glucan cell-wall layer containing β-1,3-glucan microfibrils. The LA-inhibited cells lysed. Actin cables and patches were required for bud formation and bud growth. In addition, actin patches were required for the formation of β-1,3-glucan microfibrils in the bud cell wall. LA has fungistatic, fungicidal and fungilytic effects on the budding yeast Saccharomyces cerevisiae.
- MeSH
- aktiny antagonisté a inhibitory MeSH
- antifungální látky farmakologie MeSH
- bicyklické sloučeniny heterocyklické farmakologie MeSH
- mikrobiální viabilita účinky léků MeSH
- mikroskopie MeSH
- počet mikrobiálních kolonií MeSH
- Saccharomyces cerevisiae cytologie účinky léků fyziologie MeSH
- Saccharomycetales cytologie účinky léků fyziologie MeSH
- thiazolidiny farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- aktiny MeSH
- antifungální látky MeSH
- bicyklické sloučeniny heterocyklické MeSH
- latrunculin A MeSH Prohlížeč
- thiazolidiny MeSH
L-serine is one of the proteinogenic amino acids and participates in several essential processes in all organisms. In plants, the light-dependent photorespiratory and the light-independent phosphoserine pathways contribute to serine biosynthesis. In cyanobacteria, the light-dependent photorespiratory pathway for serine synthesis is well characterized, but the phosphoserine pathway has not been identified. Here, we investigated three candidate genes for enzymes of the phosphoserine pathway in Synechocystis sp. PCC 6803. Only the gene for the D-3-phosphoglycerate dehydrogenase is correctly annotated in the genome database, whereas the 3-phosphoserine transaminase and 3-phosphoserine phosphatase (PSP) proteins are incorrectly annotated and were identified here. All enzymes were obtained as recombinant proteins and showed the activities necessary to catalyse the three-step phosphoserine pathway. The genes coding for the phosphoserine pathway were found in most cyanobacterial genomes listed in CyanoBase. The pathway seems to be essential for cyanobacteria, because it was impossible to mutate the gene coding for PSP in Synechocystis sp. PCC 6803 or in Synechococcus elongatus PCC 7942. A model approach indicates a 30-60% contribution of the phosphoserine pathway to the overall serine pool. Hence, this study verified that cyanobacteria, similar to plants, use the phosphoserine pathway in addition to photorespiration for serine biosynthesis.
- MeSH
- aktivace enzymů MeSH
- fosfoglycerátdehydrogenasa genetika metabolismus MeSH
- fosfoserin metabolismus MeSH
- metabolické sítě a dráhy * MeSH
- molekulární sekvence - údaje MeSH
- regulace genové exprese enzymů MeSH
- sekvence aminokyselin MeSH
- sekvenční seřazení MeSH
- serin metabolismus MeSH
- substrátová specifita MeSH
- světlo * MeSH
- Synechocystis fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fosfoglycerátdehydrogenasa MeSH
- fosfoserin MeSH
- serin MeSH
The ability of bacteria to bind different compounds and to adhere to biotic and abiotic surfaces provides them with a range of advantages, such as colonization of various tissues, internalization, avoidance of an immune response, and survival and persistence in the environment. A variety of bacterial surface structures are involved in this process and these promote bacterial adhesion in a more or less specific manner. In this review, we will focus on those surface adhesins and exopolymers in selected foodborne pathogens that are involved mainly in primary adhesion. Their role in biofilm development will also be considered when appropriate. Both the clinical impact and the implications for food safety of such adhesion will be discussed.
- MeSH
- Bacteria metabolismus MeSH
- bakteriální adheze * MeSH
- bakteriální adheziny analýza MeSH
- biofilmy růst a vývoj MeSH
- biopolymery metabolismus MeSH
- fyziologie bakterií * MeSH
- nemoci přenášené potravou mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- bakteriální adheziny MeSH
- biopolymery MeSH
