rDNA stability
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In recent years, global warming and the limitation of fossil fuels have been causing the governments of different countries to think about the search for more sustainable fuel sources. Biomethane (CH4) has gained increasing attention in recent years as an alternative option for a sustainable source of energy. Biogas is generated during the anaerobic digestion of organic materials by the metabolism of complex microbial communities in the substrates that make up this digestion. The microbial community evaluation using 16S rDNA metabarcoding in a bench covered pond bioreactor using swine effluent revealed the dominant bacteria belonging to Firmicutes, Proteobacteria, and Bacteroidetes phyla. The methanogenic group was represented by the Euryarchaeota phylum. It was possible to observe that the relative frequency of the methanogenic archaea community decreased with the anaerobic digestion, indicating a biological succession stage. On the other hand, there was a predominant acetogenic diversity in this final stage. These data showed stabilization of biomethane production, although the microbial community of methanogens has drastically reduced in the late process.
- MeSH
- anaerobióza MeSH
- Archaea genetika metabolismus MeSH
- biopaliva * MeSH
- bioreaktory mikrobiologie MeSH
- fosilní paliva MeSH
- hnůj * mikrobiologie MeSH
- methan metabolismus MeSH
- prasata MeSH
- ribozomální DNA genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Genes encoding ribosomal RNA (rDNA) are essential for cell survival and are particularly sensitive to factors leading to genomic instability. Their repetitive character makes them prone to inappropriate recombinational events arising from collision of transcriptional and replication machineries, resulting in unstable rDNA copy numbers. In this review, we summarize current knowledge on the structure and organization of rDNA, its role in sensing changes in the genome, and its linkage to aging. We also review recent findings on the main factors involved in chromatin assembly and DNA repair in the maintenance of rDNA stability in the model plants Arabidopsis thaliana and the moss Physcomitrella patens, providing a view across the plant evolutionary tree.
- MeSH
- Arabidopsis genetika MeSH
- DNA rostlinná genetika MeSH
- genetická transkripce MeSH
- genová dávka MeSH
- lidé MeSH
- mechy genetika MeSH
- nestabilita genomu MeSH
- oprava DNA * MeSH
- replikace DNA MeSH
- restrukturace chromatinu MeSH
- ribozomální DNA genetika MeSH
- stárnutí genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Tick cell lines are an easy-to-handle system for the study of viral and bacterial infections and other aspects of tick cellular processes. Tick cell cultures are often continuously cultivated, as freezing can affect their viability. However, the long-term cultivation of tick cells can influence their genome stability. In the present study, we investigated karyotype and genome size of tick cell lines. Though 16S rDNA sequencing showed the similarity between Ixodes spp. cell lines at different passages, their karyotypes differed from 2n = 28 chromosomes for parental Ixodes spp. ticks, and both increase and decrease in chromosome numbers were observed. For example, the highly passaged Ixodes scapularis cell line ISE18 and Ixodes ricinus cell lines IRE/CTVM19 and IRE/CTVM20 had modal chromosome numbers 48, 23 and 48, respectively. Also, the Ornithodoros moubata cell line OME/CTVM22 had the modal chromosome number 33 instead of 2n = 20 chromosomes for Ornithodoros spp. ticks. All studied tick cell lines had a larger genome size in comparison to the genomes of the parental ticks. Thus, highly passaged tick cell lines can be used for research purposes, but possible differences in encoded genetic information and downstream cellular processes, between different cell populations, should be taken into account.
Microbial and enzymatic degradation of keratin waste is more preferred over various conventional approaches which are costly and not environmentally suitable. Diverse niches are auspicious for the discovery of new microorganisms. To discover novel keratinolytic bacteria, 60 isolates from different poultry dumping sites were initially screened, and among these found a potent keratinolytic isolate (NKSP-7) that displayed higher feather-degrading ability. The selected isolate was identified as Bacillus sp. NKSP-7 based on 16S rDNA sequencing as well as physiochemical and morphological characteristics. The strain NKSP-7 showed complete hydrolysis of native chicken feathers (10 g/L) in nutrient medium after 24 h of incubation at 37 °C under agitation (150 rev/min) and produced thermostable extracellular keratinase. The crude enzyme displayed maximal keratinolytic activity (34.7 U/mL) in phosphate buffer of pH 7.0, and at 60 °C using keratin azure as a substrate. Keratinolytic enzyme showed stability at 20-65 °C for 4 h over the pH range of 5.5-8.0. No obvious inhibitory influence was perceived by cations, organic solvents, EDTA, and detergents. Whereas, enzyme activity was enhanced by adding β-mercaptoethanol, Na+, Cd2+, and Mn2+. All these notable features of keratinase make it a promising candidate for various industrial applications especially for dehairing process in leather industry, bioconversion of poultry waste, and in detergents formulations.
- MeSH
- Bacillus klasifikace genetika izolace a purifikace metabolismus MeSH
- bakteriální proteiny chemie genetika metabolismus MeSH
- biodegradace MeSH
- drůbež * MeSH
- fermentace MeSH
- keratiny analýza metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- kur domácí MeSH
- molekulová hmotnost MeSH
- odpadky - odstraňování metody MeSH
- peří chemie metabolismus MeSH
- proteasy chemie genetika metabolismus MeSH
- proteolýza MeSH
- RNA ribozomální 16S genetika MeSH
- teplota MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Cichlid fishes are the subject of scientific interest because of their rapid adaptive radiation, resulting in extensive ecological and taxonomic diversity. In this study, we examined 11 morphologically distinct cichlid species endemic to Barombi Mbo, the largest crater lake in western Cameroon, namely Konia eisentrauti, Konia dikume, Myaka myaka, Pungu maclareni, Sarotherodon steinbachi, Sarotherodon lohbergeri, Sarotherodon linnellii, Sarotherodon caroli, Stomatepia mariae, Stomatepia pindu, and Stomatepia mongo. These species supposedly evolved via sympatric ecological speciation from a common ancestor, which colonized the lake no earlier than one million years ago. Here we present the first comparative cytogenetic analysis of cichlid species from Barombi Mbo Lake using both conventional (Giemsa staining, C-banding, and CMA3/DAPI staining) and molecular (fluorescence in situ hybridization with telomeric, 5S, and 28S rDNA probes) methods. We observed stability on both macro and micro-chromosomal levels. The diploid chromosome number was 2n = 44, and the karyotype was invariably composed of three pairs of meta/submetacentric and 19 pairs of subtelo/acrocentric chromosomes in all analysed species, with the same numbers of rDNA clusters and distribution of heterochromatin. The results suggest the evolutionary stability of chromosomal set; therefore, the large-scale chromosomal rearrangements seem to be unlikely associated with the sympatric speciation in Barombi Mbo.
- MeSH
- biologická adaptace genetika účinky záření MeSH
- biologická evoluce MeSH
- chromozomální nestabilita účinky záření MeSH
- cichlidy genetika MeSH
- hybridizace in situ fluorescenční MeSH
- jezera MeSH
- karyotyp MeSH
- karyotypizace MeSH
- mapování chromozomů MeSH
- pruhování chromozomů MeSH
- telomery genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Kamerun MeSH
Paclobutrazol, (2RS, 3RS)-1-(4-chlorophenyl)-4, 4-dimethyl-2-(1H-1,2,4-triazol-1-yl) pentan-3-ol, is a plant growth retardant that mainly inhibits gibberellins (GAs) biosynthesis. In agricultural practice, paclobutrazol is applied to arrest vegetative growth so as to increase the reproductive growth of many orchard fruit, as well as grain crops. However, due to its over-application and chemical stability, paclobutrazol accumulates in soil and inhibits the growth of subsequent crops, especially those grown for vegetative purposes. The present study focused mainly on the changes in the soil bacterial community following application of paclobutrazol. Mung bean (Vigna radiata) plants were treated with paclobutrazol and cultivated for three consecutive seasons. Soil samples were collected and analyzed by denaturing gradient gel electrophoresis (DGGE) using 16S rDNA gene fragments and clone library analyses. The results obtained through clustering and clonal sequencing analysis showed that the bacterial community was affected by paclobutrazol, and in addition, was more diverse in the third stage of mung bean plant cultivation. The results of the study showed that paclobutrazol affected bacterial composition, and the population of bacteria varied greatly across time.
- MeSH
- Bacteria klasifikace účinky léků genetika izolace a purifikace MeSH
- biodiverzita MeSH
- časové faktory MeSH
- květy účinky léků růst a vývoj MeSH
- mikrobiota účinky léků MeSH
- půda chemie MeSH
- půdní mikrobiologie * MeSH
- RNA ribozomální 16S genetika MeSH
- shluková analýza MeSH
- triazoly farmakologie MeSH
- vigna účinky léků růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
Telomeres and ribosomal RNA genes (rDNA) are essential for cell survival and particularly sensitive to factors affecting genome stability. Here, we examine the role of RAD51 and its antagonist, RTEL1, in the moss Physcomitrella patens. In corresponding mutants, we analyse their sensitivity to DNA damage, the maintenance of telomeres and rDNA, and repair of double-stranded breaks (DSBs) induced by genotoxins with various modes of action. While the loss of RTEL1 results in rapid telomere shortening, concurrent loss of both RAD51 genes has no effect on telomere lengths. We further demonstrate here the linked arrangement of 5S and 45S rRNA genes in P. patens. The spacer between 5S and 18S rRNA genes, especially the region downstream from the transcription start site, shows conspicuous clustering of sites with a high propensity to form quadruplex (G4) structures. Copy numbers of 5S and 18S rDNA are reduced moderately in the pprtel1 mutant, and significantly in the double pprad51-1-2 mutant, with no progression during subsequent cultivation. While reductions in 45S rDNA copy numbers observed in pprtel1 and pprad51-1-2 plants apply also to 5S rDNA, changes in transcript levels are different for 45S and 5S rRNA, indicating their independent transcription by RNA polymerase I and III, respectively. The loss of SOL (Sog One-Like), a transcription factor regulating numerous genes involved in DSB repair, increases the rate of DSB repair in dividing as well as differentiated tissue, and through deactivation of G2/M cell-cycle checkpoint allows the cell-cycle progression manifested as a phenotype resistant to bleomycin.
- MeSH
- DNA-helikasy genetika metabolismus MeSH
- genetické lokusy MeSH
- mechy enzymologie genetika MeSH
- mutace MeSH
- nestabilita genomu * MeSH
- rekombinasa Rad51 genetika metabolismus MeSH
- ribozomální DNA genetika MeSH
- RNA ribozomální 18S genetika MeSH
- RNA ribozomální 5S genetika MeSH
- RNA ribozomální genetika MeSH
- rostlinné proteiny genetika metabolismus MeSH
- telomery genetika MeSH
- transkripční faktory genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An agar well diffusion assay (AWDA) was used to isolate a high bacteriocin-producing strain with a broad spectrum of antibacterial activity, strain MXG-68, from Inner Mongolia traditional fermented koumiss. Lactobacillus plantarum MXG-68 was identified by morphological, biochemical, and physiological characteristics and 16S rDNA analysis. The production of antibacterial substance followed a growth-interrelated model, starting at the late lag phase of 4 h and arriving at a maximum value in the middle of the stationary phase at 24 h. Antibacterial activity was abolished or decreased in the presence of pepsin, chymotrypsin, trypsin, proteinase, and papain K. The results showed that antibacterial substances produced by L. plantarum MXG-68 were proteinaceous and could thus be classified as the bacteriocin, named plantaricin MXG-68. The molar mass of plantaricin MXG-68 was estimated to be 6.5 kDa, and the amino acid sequence of its N-terminal was determined to be VYGPAGIFNT. The mode of plantaricin MXG-68 action was determined to be bactericidal. Bacteriocin in cell-free supernatant (CFS) at pH 7 was stable at different temperatures (60 °C, 80 °C, 100 °C, 121 °C for 30 min; 4 °C and - 20 °C for 30 days), as well as at pH 2.0-10.0. Antibacterial activity maintained stable after treatment with organic solvents, surfactants, and detergents but increased in response to EDTA. Response surface methodology (RSM) revealed the optimum conditions of bacteriocin production in L. plantarum MXG-68, and the bacteriocin production in medium optimized by RSM was 26.10% higher than that in the basal MRS medium.
- MeSH
- antibakteriální látky biosyntéza chemie farmakologie MeSH
- bakteriociny biosyntéza chemie farmakologie MeSH
- fylogeneze MeSH
- kinetika MeSH
- kultivační média MeSH
- kumys mikrobiologie MeSH
- Lactobacillus plantarum chemie klasifikace fyziologie MeSH
- molekulová hmotnost MeSH
- potravinářská mikrobiologie MeSH
- RNA ribozomální 16S genetika MeSH
- sekvence aminokyselin MeSH
- stabilita proteinů MeSH
- Staphylococcus účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Čína MeSH
Tyrophagus putrescentiae is inhabited by bacteria that differ among mite populations (strains) and diets. Here, we investigated how the microbiome and fitness of Tputrescentiae are altered by dietary perturbations and mite populations. Four T. putrescentiae populations, referred to as dog, Koppert, laboratory, and Phillips, underwent a perturbation, i.e., a dietary switch from a rearing diet to two experimental diets. The microbiome was investigated by sequencing the V1-V3 portion of the 16S rRNA gene, and selected bacterial taxa were quantified by quantitative PCR (qPCR) using group/taxon-specific primers. The parameters observed were the changes in mite population growth and nutritional status, i.e., the total glycogen, lipid, saccharide, and protein contents in mites. The effect of diet perturbation on the variability of the microbiome composition and population growth was lower than the effect induced by mite population. In contrast, the diet perturbation showed a greater effect on nutritional status of mites than the mite population. The endosymbionts exhibited high variations among T. putrescentiae populations, including Cardinium in the laboratory population, Blattabacterium-like bacteria in the dog population, and Wolbachia in the dog and Phillips populations. Solitalea-like and Bartonella-like bacteria were present in the dog, Koppert, and Phillips populations in different proportions. The T. putrescentiae microbiome is dynamic and varies based on both the mite population and perturbation; however, the mites remain characterized by robust bacterial communities. Bacterial endosymbionts were found in all populations but represented a dominant portion of the microbiome in only some populations.IMPORTANCE We addressed the question of whether population origin or perturbation exerts a more significant influence on the bacterial community of the stored product mite Tyrophagus putrescentiae The microbiomes of four populations of T. putrescentiae insects subjected to diet perturbation were compared. Based on our results, the bacterial community was more affected by the mite population than by diet perturbation. This result can be interpreted as indicating high stability of the putative intracellular symbionts in response to dietary perturbation. The changes in the absolute and relative numbers of Wolbachia, Blattabacterium-like, Solitalea-like, and Cardinium bacteria in the T. putrescentiae populations can also be caused by neutral processes other than perturbation. When nutritional status is considered, the effect of population appeared less important than the perturbation. We hypothesize that differences in the proportions of the endosymbiotic bacteria result in changes in mite population growth.
- MeSH
- Acaridae mikrobiologie MeSH
- Bacteria klasifikace genetika MeSH
- dieta metody MeSH
- DNA bakterií chemie genetika MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- ribozomální DNA chemie genetika MeSH
- RNA ribozomální 16S genetika MeSH
- sekvenční analýza DNA MeSH
- shluková analýza MeSH
- stravovací zvyklosti MeSH
- střevní mikroflóra * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Collisions between replication and transcription machineries represent a significant source of genomic instability. RECQ5 DNA helicase binds to RNA-polymerase (RNAP) II during transcription elongation and suppresses transcription-associated genomic instability. Here, we show that RECQ5 also associates with RNAPI and enforces the stability of ribosomal DNA arrays. We demonstrate that RECQ5 associates with transcription complexes in DNA replication foci and counteracts replication fork stalling in RNAPI- and RNAPII-transcribed genes, suggesting that RECQ5 exerts its genome-stabilizing effect by acting at sites of replication-transcription collisions. Moreover, RECQ5-deficient cells accumulate RAD18 foci and BRCA1-dependent RAD51 foci that are both formed at sites of interference between replication and transcription and likely represent unresolved replication intermediates. Finally, we provide evidence for a novel mechanism of resolution of replication-transcription collisions wherein the interaction between RECQ5 and proliferating cell nuclear antigen (PCNA) promotes RAD18-dependent PCNA ubiquitination and the helicase activity of RECQ5 promotes the processing of replication intermediates.
- MeSH
- biologické modely MeSH
- DNA řízené RNA-polymerasy metabolismus MeSH
- DNA vazebné proteiny metabolismus MeSH
- DNA-dependentní DNA-polymerasy metabolismus MeSH
- elongace genetické transkripce MeSH
- fyziologický stres genetika MeSH
- genetická transkripce * MeSH
- HEK293 buňky MeSH
- helikasy RecQ metabolismus MeSH
- interakční proteinové domény a motivy MeSH
- lidé MeSH
- multienzymové komplexy metabolismus MeSH
- otevřené čtecí rámce genetika MeSH
- prekurzory RNA genetika MeSH
- proliferační antigen buněčného jádra metabolismus MeSH
- protein BRCA1 metabolismus MeSH
- rekombinasa Rad51 metabolismus MeSH
- replikace DNA * MeSH
- ribozomální DNA metabolismus MeSH
- ubikvitinace MeSH
- ubikvitinligasy metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH