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Antibiotics-modes of action, resistance mechanisms and the search for new compounds
Spížek, Jaroslav
According to their mechanism of action antibiotics can be divided into 4 groups. 1. Antibiotics inhibiting bacterial cell wall biosynthesis. 2. Antibiotics inhibiting DNA synthesis. 3. Antibiotics inhibiting RNA synthesis and 4. Antibiotics inhibiting protein synthesis. Basic mechanisms of antibiotic resistance include cell impermeability, modification of target site, modification or degradation of the antibiotic and increased efflux of the antibiotic. The following can be used in the search for new compounds: 1. Microorganisms isolated from extreme life conditions 2. Environmental DNA (eDNA) in which genes coding for secondary metabolites are looked for. 3. Streptomyces genomics yielding information about genes coding biosynthesis of new compounds. 4. Combinatorial biosynthesis for the production of hybrid antibiotics.
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Ekologické vazby ohledně endolitických producentů mikrovrteb a substrátů v barrandienských vápencích devonského stáří, Česká republika
Hladil, Jindřich
The microboring activity in barrandian seas was generally low. It was limited by relatively cold geostrophic currents in outer parts, and the seafloors in inner basin depressions were also adversely influenced by stagnant d18O-positive and heavy-metal-rich bottom waters. The really flourished microborers were only in two stratigraphical intervals, and both have shown /"redbeds-like/" deposits. The first developed close with major end-Tippecanoe regressions in Praha sequence, and the second occurred in the Daleje-Trebotov sequence. These /"redbeds-like/" periods correspond mineralogically, geochemically and paleobiologically to relatively hot humid climates (~ mesotrophic but well oxygenated waters). It differed from other long intervals characterized by marine Corg and silica burial (cherts)
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Rozdělení velkých genomů čeledi Triticeae tříděných chromozomů
Doležel, Jaroslav ; Kubaláková, Marie ; Suchánková, Pavla ; Šafář, Jan ; Janda, Jaroslav ; Kovářová, Pavlína ; Bartoš, Jan ; Čihalíková, Jarmila ; Šimková, Hana
Nuclear genomes of some Triticeae species are characterized by large size and prevalence of repetitive DNA sequences. These features hamper their physical mapping and gene cloning. Purification of individual chromosomes by flow cytometry can simplify these tasks by providing small and defined genome fractions. This lecture reviews the development of the methodology and its potential for genome mapping in barley, rye and wheat Due to small differences in relative DNA content, only one chromosome type can be discriminated and sorted in each of the three species. Cytogenetic stocks facilitate separation of other parts of the genomes as individual chromosomes, translocation chromosomes and chromosome arms. Chromosome analysis by flow cytometry permits quantitative detection of structural and numerical chromosome changes. Chromosomes sorted onto microscopic slides have been used for discovery of rare structural changes and for high-resolution cytogenetic mapping using FISH. The use of sorted chromosomes for HAPPY mapping, targeted isolation of low copy "genie" sequences, and high-throughput physical mapping of ESTs on microarrays are attractive options. As millions of chromosomes with intact DNA may be sorted, construction of BAC libraries is possible. Subgenomic, chromosome-specific and chromosome arm-specific BAC libraries have already been produced in wheat and represent unique resources for genomics of cereals.
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The Idea of Gene and some of It's Ethical Consequences
Franková, Věra ; Payne, Jan (advisor) ; Brdička, Radim (referee) ; Križan, Peter (referee)
The term gene was coined in 1909 by Wilhelm Johannsen to designate theoretical unit of genetic analysis. Concept of the gene has changed over time due to progress in genetics and its experimental practice. Currently used molecular concept is based on linear correspondence between DNA sequence and its product (Waters 2007). It also describes gene as discrete physical structure - DNA segment with clearly defined boundaries. But the investigation of wide range of genomes has put the molecular concept of gene into doubt. The aim of PhD thesis is to specify the term gene by employing mechanical, semantic and hermeneutic interpretation (Payne 2002, 101-124). It summarizes history of the gene and presents some of the biological findings that undermine the molecular concept. In biological context the gene is always connected to DNA molecule. But it can be shown that DNA functions only as a mediator or carrier, and the substance of gene is not material but it has a character of information. Therefore in the semantic view the gene is information containing instruction for development of phenotypic trait which is specified by medical or other theoretical interest. Hermeneutical interpretation of the gene can be point out in clinical genetics. Here the gene is also information containing instruction for development of...
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DNA viral infection in patients following allogeneic transplantation of bone marrow
Hubáček, Petr ; Cinek, Ondřej (advisor) ; Šterzl, Ivan (referee) ; Mayer, Jiří (referee) ; Žák, Pavel (referee)
Infectious complications are very common after haematopoietic stem cell transplantation (HSCT). Beside bacterial and mycotic infections, viral infections are important cause of morbidity and mortality of these patients. Among viral infections, the most common are infections caused by DNA viruses. Between January 2001 and October 2008, we have tested samples from 217 paediatric and 382 adult patients after HSCT. In total, we have tested 15 757 samples (median 31 samples for children, 20 for adult). Among them, there was 14 867 samples of peripheral blood and 890 samples of other biological materials (urine, stool, CSF etc.). Quantity of HSV, VZV, CMV, HHV-6, HHV-7, EBV, adenoviruses of group A-C, BKV and albumin gene was tested using quantitative real-time PCR technology. Results of CMV, HHV-6, HHV-7 and EBV were normalized to 10 000 human genome equivalents. HSV and VZV were detected in minute number of samples. Threshold for virostatic therapy was assessed to 100 normalized viral copies for CMV. This level was crossed in 55 children and 123 adults. Despite the virostatic treatment, symptoms of CMV infections developed in 68 patients. CMV disease, alone or in the consequence of other post-transplant complications, was observed in 20 patients, fatal in 17 of them. In 4 paediatric patients, we have detected...
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Blastocystis subtypes in pigs
LAKATOSOVÁ, Lucie
Blastocystis is an anaerobic single-celled protozoan that commonly occurs in the intestinal tract of animals and humans. It is a genetically very variable organism. Blastocystis can be found both in healthy specimens and in patients with gastrointestinal disorders. In 2011/2012, I examinated already isolated DNA samples from domestic and wild pigs by molecular methods in the laboratory of the ASCR Parasitology Institute. In total, 110 samples were examined. The domestic pigs were positive in 91 % (51/56) and wild pigs in 67 % (36/54). The overall prevalence of domestic pigs was higher by 24 %. Several sequences of SSU rRNA gene obtained during the work suggest that pigs may serve as host for atypical Blastocystis subtypes.
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Making Transgenic \kur{C. elegans} with Polycistronic mCherry Vector
FARKA, Dominik
Creation of transgenic animals has become a popular method to analyse gene function. In the nematode Ceanorhabditis elegans transformation is widely used and can be achieved by microinjection. For functional analyses, transgene constructs typically contain a promoter driving the expression of the protein of interest that is fused to a fluorescent protein. However, as this fusion of proteins can lead to misfolding of the protein of interest and may not reflect proper function, a modification of the expression vector has been developed; introducing a short sequence of non-coding DNA in-between the sequences of the two proteins and making the construct compatible with a polycistronic operon system. In this study, four different polycistronic constructs were introduced into C. elegans by means of microinjection in order to provide new tools for the analyses of gene function. Tissue specific promoters wrt-2 (seam cells), grl-21 (hyp7), and egl-17 (vulval precursor cells) were used to over-express either NHR-25 or SMO-1 in the corresponding tissues and the expression was visualized by independently translated mCherry red fluorescent. 10 independent transformed C. elegans strains were established and corresponding tissue-specific promoter activities were confirmed. Furthermore, in some cases, ectopic behaviour was observed e.g. ectopic mCherry expression in different tissues or specific cell differentiation defects that was most likely caused by the overexpression of NHR-25 or SMO-1. This study was the first case in our laboratory to generate transformed C. elegans utilizing the polycistronic mCherry vector system. New genetic tools were introduced in the laboratory useful for further analyses of gene function.
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