Globally, the occurrence of biofilm associated infection has become an alarming menace to the medical fraternity because the thick exopolysaccharide layer encasing the biofilms makes the biofilm producing pathogens inherently resistant to antibiotics. Candida albicans, the most common pathogen among Candida spp. is the causative agent for superficial and invasive candidiasis. The morphological phase switching from yeast to hyphal form is one of the virulent traits of C. albicans critical for its pathogenicity. Owing to the emergence of antifungal resistance among this opportunistic fungus, there is a dire need for improvised alternative antifungal agents. In the present study, we have evaluated a biosurfactant from a marine bacterium for its biofilm disruption ability against C. albicans. This biosurfactant had the potential to disrupt biofilms as well as to inhibit the morphological transition from yeast to hyphae. In addition, this biosurfactant showed enhance disruption of mixed species biofilms of C. albicans and Staphylococcus epidermidis when combined with DNase isolated from marine bacteria. From the results obtained, it is evident that the biosurfactant could act as a potential antibiofilm agent against drug resistant C. albicans strains.

• MeSH
• antifungální látky farmakologie   MeSH
• Bacteria * enzymologie   MeSH
• biofilmy * účinky léků   MeSH
• Candida albicans * účinky léků   MeSH
• deoxyribonukleasy * metabolismus   MeSH
• hyfy MeSH
• kandidóza mikrobiologie   MeSH
• lidé MeSH
• Staphylococcus epidermidis účinky léků   MeSH
• vodní organismy * enzymologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Circulating extracellular DNA (ecDNA) is known to worsen the outcome of many diseases. ecDNA released from neutrophils during infection or inflammation is present in the form of neutrophil extracellular traps (NETs). It has been shown that higher ecDNA concentration occurs in a number of inflammatory diseases including inflammatory bowel disease (IBD). Enzymes such as peptidyl arginine deiminases (PADs) are crucial for NET formation. We sought to describe the dynamics of ecDNA concentrations and fragmentation, along with NETosis during a mouse model of chemically induced colitis. Plasma ecDNA concentration was highest on day seven of dextran sulfate sodium (DSS) intake and the increase was time-dependent. This increase correlated with the percentage of cells undergoing NETosis and other markers of disease activity. Relative proportion of nuclear ecDNA increased towards more severe colitis; however, absolute amount decreased. In colon explant medium, the highest concentration of ecDNA was on day three of DSS consumption. Early administration of PAD4 inhibitors did not alleviate disease activity, but lowered the ecDNA concentration. These results uncover the biological characteristics of ecDNA in IBD and support the role of ecDNA in intestinal inflammation. The therapeutic intervention aimed at NETs and/or nuclear ecDNA has yet to be fully investigated.

• MeSH
• biologické markery metabolismus   MeSH
• deoxyribonukleasy metabolismus   MeSH
• DNA krev   metabolismus   MeSH
• endoskopie MeSH
• extracelulární pasti účinky léků   metabolismus   MeSH
• extracelulární prostor metabolismus   MeSH
• kolitida krev   chemicky indukované   patologie   MeSH
• mitochondriální DNA krev   MeSH
• myši inbrední C57BL MeSH
• ornithin analogy a deriváty   farmakologie   MeSH
• peptidylarginindeiminasa typu 4 metabolismus   MeSH
• síran dextranu MeSH
• streptonigrin farmakologie   MeSH
• střeva účinky léků   patologie   MeSH
• střevní sliznice účinky léků   patologie   MeSH
• stupeň závažnosti nemoci MeSH
• zánět krev   patologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The release of neutrophil extracellular traps (NETs) is one of the weapons neutrophils have in their armory. NETs consist of extracellular chromatin fibers decorated with a plethora of cytoplasmic and granular proteins, such as the antimicrobial serine protease neutrophil elastase (NE). Because the first description of NETs as beneficial to the host, reports on their double-faced role in health and disease have considerably increased recently. On one hand, NETs reportedly trap and kill bacteria and also participate in the resolution of the acute inflammation associated with infection and with tissue damage. On the other hand, numerous negative aspects of NETs contribute to the etiopathogenesis of autoimmune disorders. Employing soluble and solid fluorescent substrates, we demonstrate the interaction of NE with aggregated NETs (aggNETs), the limitation of its enzymatic activity and the containment of the enzyme from surrounding tissues. These events prevent the spread of inflammation and tissue damage. The detection of DNase 1-dependent elevation of NE activity attests the continuous presence of patrolling neutrophils forming NETs and aggNETs even under conditions physiologic conditions.

• MeSH
• aktivace enzymů MeSH
• deoxyribonukleasa I metabolismus   MeSH
• deoxyribonukleasy metabolismus   MeSH
• extracelulární pasti imunologie   metabolismus   MeSH
• leukocytární elastasa metabolismus   MeSH
• lidé MeSH
• myši MeSH
• neutrofily imunologie   metabolismus   MeSH
• tělesné tekutiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Ulcerative colitis and Crohn's disease constitute the two main forms of inflammatory bowel disease. Prevalence of these diseases increases. In the present day, inadequate and inefficient therapy causes complications and frequent relapse. Extracellular DNA (ecDNA) is the DNA that is outside of cells and may be responsible for activation of the inflammatory response. To determine whether colitis is associated with higher concentration of ecDNA we used male mice of the C57BL/6 strain. Colitis was induced by 2% dextran sulphate sodium (DSS). After 7 days, mice exhibited considerable weight loss compared to the control group. Also, there was a higher stool consistency score and the colon was significantly shorter in comparison to the control group. Higher concentration of ecDNA was found in the DSS group. Interestingly, deoxyribonuclease activity was lower in the colon of the DSS group compared with the negative control. These findings may point to ecDNA as a potential pathogenetic factor and marker of inflammation.

• MeSH
• biologické markery metabolismus   MeSH
• deoxyribonukleasy metabolismus   MeSH
• DNA krev   metabolismus   MeSH
• gastrointestinální trakt enzymologie   MeSH
• kolitida krev   metabolismus   patologie   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• síran dextranu MeSH
• tělesná hmotnost MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Circulating cell-free DNA (cfDNA) may be involved in immune response regulation. We studied the variations in abundance of telomeric sequences in plasma and serum in young healthy volunteers and the ability of cfDNA contained in these samples to co-activate the TNF-α m RNA expression in monocytes. We performed qPCR to determine relative telomere length (T/S ratios) in plasma, serum and whole blood of 36 volunteers. Using paired samples of plasma and serum and DNase treatment, we analysed the contribution of cfDNA to the co-activation of TNF-α mRNA expression in THP1 monocytic cell line. We found significant differences between paired plasma and serum samples in relative T/S ratios (median 1.38 ± 1.1 vs. 0.86 ± 0.25, respectively) and in total amounts of cfDNA and in estimated total amounts of telomeres which were significantly higher in serum than in plasma. TNF-α mRNA expression in THP1 cells increased significantly after DNase treatment of all samples used for stimulation. The highest TNF-α mRNA expressions were observed after stimulation with DNase treated serum samples. Our results suggest that the different content of telomeric sequences in plasma and serum may contribute to the tuning of immune response. Further studies of this interesting phenomenon are needed.

• MeSH
• deoxyribonukleasy metabolismus   MeSH
• homeostáza telomer MeSH
• imunita MeSH
• imunomodulace MeSH
• krevní plazma imunologie   metabolismus   MeSH
• lidé MeSH
• mladý dospělý MeSH
• monocyty fyziologie   MeSH
• sérum imunologie   metabolismus   MeSH
• telomery genetika   MeSH
• THP-1 buňky MeSH
• TNF-alfa genetika   metabolismus   MeSH
• upregulace MeSH
• volné cirkulující nukleové kyseliny genetika   imunologie   metabolismus   MeSH
• zdraví dobrovolníci pro lékařské studie MeSH
• Check Tag
• lidé MeSH
• mladý dospělý MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

Genomic DNA is constantly challenged from endogenous as well as exogenous sources. The DNA damage response (DDR) mechanism has evolved to combat these challenges and ensure genomic integrity. In this review, we will focus on repair of DNA double-strand breaks (DSB) by homologous recombination and the role of several nucleases and other recombination factors as suitable targets for cancer therapy. Their inactivation as well as overexpression have been shown to sensitize cancer cells by increasing toxicity to DNA-damaging agents and radiation or to be responsible for resistance of cancer cells. These factors can also be used in targeted cancer therapy by taking advantage of specific genetic abnormalities of cancer cells that are not present in normal cells and that result in cancer cell lethality.

• MeSH
• cílená molekulární terapie MeSH
• deoxyribonukleasy antagonisté a inhibitory   genetika   metabolismus   MeSH
• enzymy opravy DNA antagonisté a inhibitory   genetika   metabolismus   MeSH
• homologní rekombinace * MeSH
• inhibitory enzymů farmakologie   terapeutické užití   MeSH
• lidé MeSH
• nádory farmakoterapie   enzymologie   genetika   MeSH
• rekombinační oprava DNA * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Type I plant nucleases play an important role in apoptotic processes and cell senescence. Recently, they have also been indicated to be potent anticancer agents in in vivo studies. The first structure of tomato nuclease I (TBN1) has been determined, its oligomerization and activity profiles have been analyzed and its unexpected activity towards phospholipids has been discovered, and conclusions are drawn regarding its catalytic mechanism. The structure-solution process required X-ray diffraction data from two crystal forms. The first form was used for phase determination; the second form was used for model building and refinement. TBN1 is mainly α-helical and is stabilized by four disulfide bridges. Three observed oligosaccharides are crucial for its stability and solubility. The active site is localized at the bottom of the positively charged groove and contains a zinc cluster that is essential for enzymatic activity. An equilibrium between monomers, dimers and higher oligomers of TBN1 was observed in solution. Principles of the reaction mechanism of the phosphodiesterase activity are suggested, with central roles for the zinc cluster, the nucleobase-binding pocket (Phe-site) and Asp70, Arg73 and Asn167. Based on the distribution of surface residues, possible binding sites for dsDNA and other nucleic acids with secondary structure were identified. The phospholipase activity of TBN1, which is reported for the first time for a nuclease, significantly broadens the substrate promiscuity of the enzyme, and the resulting release of diacylglycerol, which is an important second messenger, can be related to the role of TBN1 in apoptosis.

• MeSH
• deoxyribonukleasy chemie   metabolismus   MeSH
• fosfolipasy chemie   metabolismus   MeSH
• katalytická doména MeSH
• krystalizace MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• multienzymové komplexy chemie   metabolismus   MeSH
• myši MeSH
• rostlinné proteiny chemie   metabolismus   MeSH
• Solanum lycopersicum enzymologie   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Engineered nucleases are proteins that are able to cleave DNA at specified sites in the genome. These proteins have recently been used for gene targeting in a number of organisms. We showed earlier that zinc finger nucleases (ZFNs) can be used for generating gene-specific mutations in Bombyx mori by an error-prone DNA repair process of non-homologous end joining (NHEJ). Here we test the utility of another type of chimeric nuclease based on bacterial TAL effector proteins in order to induce targeted mutations in silkworm DNA. We designed three TAL effector nucleases (TALENs) against the genomic locus BmBLOS2, previously targeted by ZFNs. All three TALENs were able to induce mutations in silkworm germline cells suggesting a higher success rate of this type of chimeric enzyme. The efficiency of two of the tested TALENs was slightly higher than of the successful ZFN used previously. Simple design, high frequency of candidate targeting sites and comparable efficiency of induction of NHEJ mutations make TALENs an important alternative to ZFNs.

• MeSH
• bourec embryologie   genetika   MeSH
• deoxyribonukleasy metabolismus   MeSH
• genetické vektory MeSH
• genový targeting metody   MeSH
• molekulární sekvence - údaje MeSH
• mutační analýza DNA MeSH
• otevřené čtecí rámce MeSH
• Saccharomyces cerevisiae MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Differentiation of the oxidase positive staphylococci, Staphylococcus sciuri, Staphylococcus lentus, Staphylococcus vitulinus and Staphylococcus fleurettii, based on tributyrin, urease, caseinase, gelatinase and DNase activity is described. These tests may be used for preliminary identification of oxidase positive isolates of staphylococci resulting in more accurate identification of these species.

• MeSH
• deoxyribonukleasy metabolismus   MeSH
• druhová specificita MeSH
• lidé MeSH
• metaloendopeptidasy metabolismus   MeSH
• mikrobiologie životního prostředí MeSH
• oxidoreduktasy metabolismus   MeSH
• potravinářská mikrobiologie MeSH
• senzitivita a specificita MeSH
• stafylokokové infekce mikrobiologie   MeSH
• Staphylococcus klasifikace   enzymologie   MeSH
• techniky typizace bakterií metody   MeSH
• triglyceridy metabolismus   MeSH
• ureasa metabolismus   MeSH
• želatinasy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Jugoslávie MeSH

AIMS: A kinetic 5'-nuclease polymerase chain reaction (real-time PCR) for the quantification of Escherichia coli was developed. METHODS AND RESULTS: Specific primers and a fluorogenic probe oriented to sfmD gene, encoding a putative outer membrane export usher protein, were designed. The PCR system was highly specific and sensitive for E. coli, as determined with 37 non-E. coli strains (exclusivity, 100%) and 24 E. coli strains (inclusivity, 100%). When used in real-time PCR, linear calibration lines were obtained in the range from 10(2) to 10(8) CFU ml(-1) for three E. coli strains. Salmonella Enteritidis (10(6) CFU ml(-1)) or Citrobacter freundii (10(6) CFU ml(1)) had no effect on quantification of E. coli by the method. CONCLUSIONS: The developed real-time PCR is suitable for rapid quantification of E. coli. SIGNIFICANCE AND IMPACT OF THE STUDY: In connection to an appropriate sample preparation technique, the method is suitable for food safety and technological hygiene applications.

• MeSH
• deoxyribonukleasy metabolismus   MeSH
• DNA bakterií analýza   MeSH
• Escherichia coli genetika   izolace a purifikace   MeSH
• financování organizované MeSH
• kinetika MeSH
• polymerázová řetězová reakce metody   MeSH
• potravinářská mikrobiologie MeSH
• proteiny vnější bakteriální membrány genetika   MeSH
• proteiny z Escherichia coli genetika   MeSH