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Preparation of genetically manipulated producers of hybrid manumycins
Krýslová, Dita ; Petříčková, Kateřina (advisor) ; Doubravová, Linda (referee)
Streptomyces are one of the most prolific producers of various secondary metabolites. Manumycin antibiotics represent an important class of these compounds. They belong to a big class of polyketide metabolites. While their antibiotic effect is not very significant, their other biological properties have a big potential in the treatment of inflammations, tumors, etc. They are characterized by two short polyketide chains, which are attached to a central subunit. At the end of the lower polyketide chain, a C5N cyclic unit is frequently attached. This thesis originates from the colabomycin E, an antibiotic, which was discovered by our team. This antibiotic is a new member of manumycin-type metabolites and is produced by Streptomyces aureus SOK1/5-04 strain. Previous studies on the function of individual genes in the biosynthetic gene cluster of colabomycin E inspired us to consider editing of the current biological activity of colabomycin E by replacement of the C5N unit with another, structurally similar bioactive subunit. Due to high structural similarity, we have selected 4,7- dihydroxycoumarin unit of novobiocin, an aminocoumarin-type metabolite produced also by Streptomyces. The 4,7-dihydroxycoumarin unit is pharmacophore with a cancerostatic activity. We expected that the cancerostatic activity...
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Specific features of streptomycetes isolated from human tissues
Kodatová, Anežka ; Petříčková, Kateřina (advisor) ; Zikánová, Blanka (referee)
This bachelor thesis focuses on activities of the bacterial genus Streptomyces in relations to plants, animals and human. Many cases of their symbiotic relationships with plants are known, but there is also a common plant pathogen S. scabies. As a primary soil bacteria, their association with animals is infrequent, but not exceptional. Symbiotic relationships have been observed for example in several insect species. Streptomyces have been repeatedly isolated from the human microbiome, however only a little information about their influence on human body is available. Due to the wide production of secondary metabolites affecting other microorganisms, their role can be assumed as significant. The relationship between human Streptomyces and human could have a parallel in the Streptomyces symbiosis with plants and insects, but it can also have certain effects on pathogenesis. The ability of beta haemolysis was demonstrated in tested strains. In addition, there are cases of serious diseases caused by Streptomyces. Next to the relatively common actinomycosis in the regions of Sudan and India, diseases such as pneumonia or abscess were reported.
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Analysis of streptomycete isolates carrying a cyclizing aminolevulinate synthase gene
Rašmanová, Petra ; Petříčková, Kateřina (advisor) ; Felsberg, Jurgen (referee)
Streptomyces bacteria are well-known producents of many bioactive metabolites. Its secondary metabolism is a source of many important groups of active compounds that are recently investigated by means of many new methods based on bioinformatic analyses of genome data, modern LC-MS techniques, and metabolic modeling methods. This thesis originates from the genetic screening for a specific gene (als) for cyclizing 5-aminolevulinate synthase. Based on earlier studies, we consider this gene as a genetic tag of the producers of secondary metabolites containing the C5N unit (2-amino-3-hydroxycyklopent- 2-enon). Such metabolites include several groups with variable structures and biological activities, which include manumycins as well. Manumycins are small polyketides with a weak antibiotic aktivity, especially against gram-positive bacteria. However, its cancerostatic and anti-inflammatory effects are of greater importance. Streptomyces monomycini BCCO10 1552 and Streptomyces capoamus BCCO10 1636 strains were found positive for the presence of the als gene in the targeted genetic screening. By the als phylogeny, they cluster near the producents of manumycin compounds. This thesis aimed to determine whether these new natural isolates produce any compounds containing C5N unit, and to characterize them in...
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Analysis of signaling cascade of protein kinase StkP in Streptococcus pneumoniae
Holečková, Nela ; Doubravová, Linda (advisor) ; Lichá, Irena (referee) ; Petříčková, Kateřina (referee)
Analysis of signaling cascade of protein kinase StkP in Streptococcus pneumoniae Streptococcus pneumoniae is not only an important human pathogen but also an appropriate model organism to investigate cell division in ovoid bacteria. This bacterium lacks both, NO and Min systems for selection of cell division site. Thus, the mechanism which determines the site of cell division is unknown. Additionally, the genome of S. pneumoniae encodes a single gene for eukaryotic-like serine/threonine protein kinase StkP and a single gene for eukaryotic-like serine/threonine protein phosphatase of PP2C type called PhpP. StkP is one of the main regulators of cell division. Cell division is probably affected by the phosphorylation of its substrates, which include, among others, cell division proteins FtsZ, FtsA, DivIVA, MacP, Jag/KhpB/EloR, and LocZ/MapZ. The aim of the first project of this dissertation thesis is determination of the function of protein LocZ in the cell division. In summary, locZ is not essential, however, it is involved in proper septum placement in S. pneumoniae and our data suggest that it is a positive regulator of Z-ring placement. Cells lacking LocZ are able to form Z-ring, but the Z-ring is spatially misplaced resulting in cell division defects, shape deformation, and generation of unequally sized,...
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Colonization of human lung by non-pathogenic streptomycetes
Herbrík, Andrej ; Petříčková, Kateřina (advisor) ; Zikánová, Blanka (referee)
Streptomycetes, primary soil saprophytic microorganisms are at the center of interest in many research groups, mainly because of their ability to produce a wide range of biologically active substances useful in medicine, biotechnology and agriculture. The marginal, and little explored areas are the interactions that streptomycetes create with humans. Recent metagenomic studies have shown that streptomycetes colonize the skin, the respiratory and possibly the urogenital tract of humans. In addition to apparent pathogens such as S. somaliensis and S. sudanensis, the clinical impact of these streptomycetes on human health is unknown. For this reason, a unique collection of non-pathogenic streptomycetes isolated from human clinical specimens was developed. The isolates were collected by the National Reference Laboratory for Pathogenic Actinomycetes in Trutnov, Czech Republic. On the basis of pilot studies, an isolate labeled TR42 was selected from the Trutnov collection, showing a very broad spectrum of biological activities. This strain was isolated from sputum from a patient with unknown respiratory diagnosis. The TR42 strain exhibits considerable biotechnological potential and after following a thorough study, it could be a source of new biologically active substances with pharmaceutically...
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Specific features of streptomycetes isolated from human tissues
Kodatová, Anežka ; Petříčková, Kateřina (advisor) ; Zikánová, Blanka (referee)
This bachelor thesis focuses on activities of the bacterial genus Streptomyces in relations to plants, animals and human. Many cases of their symbiotic relationships with plants are known, but there is also a common plant pathogen S. scabies. As a primary soil bacteria, their association with animals is infrequent, but not exceptional. Symbiotic relationships have been observed for example in several insect species. Streptomyces have been repeatedly isolated from the human microbiome, however only a little information about their influence on human body is available. Due to the wide production of secondary metabolites affecting other microorganisms, their role can be assumed as significant. The relationship between human Streptomyces and human could have a parallel in the Streptomyces symbiosis with plants and insects, but it can also have certain effects on pathogenesis. The ability of beta haemolysis was demonstrated in tested strains. In addition, there are cases of serious diseases caused by Streptomyces. Next to the relatively common actinomycosis in the regions of Sudan and India, diseases such as pneumonia or abscess were reported.
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Identification and activation of a cryptic biosynthetic gene cluster for manumycin-type metabolites in Saccharothrix espanaensis DSM44229
Zelenka, Tomáš ; Petříčková, Kateřina (advisor) ; Beranová, Jana (referee)
1 Abstract: Secondary metabolism of Gram-positive soil bacteria from the genus Streptomyces is a inestimable source of natural products including manumycins, which belong to a polyketide group. These products possess weak antimicrobial, but important antiinflammatory, and antitumor activities. Streptomyces sp. offers broad amounts of yet undiscovered antibiotics, potentially utilizable in clinical medicine. This fact makes out of these organisms a promising solution to our present problem with rising antibiotic resistance among microorganisms. Two main ways are applied in this research: There are efforts of prepairing new derivates based on known products and creating various modifications in their structure. Next, new producers are discovered by "genome mining" methods, activation of silent gene clusters, followed by improvements of antibiotic production. One of those silent clusters was found in the Saccharothrix espanaensis DSM44229 strain. The genetic information has been transferred to a heterologous host in order to characterize its product. Cluster activation and production of novel manumycin-type metabolites occurred in the host after the transfer.
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Characterization of N-demethyllincomycin-methyltransferase.
Poľan, Marek ; Najmanová, Lucie (advisor) ; Petříčková, Kateřina (referee)
Lincomycin is a naturally occurring member of a lincosamide group of antibiotics. The cluster of lincomycin biosynthetic gene was already decribed and the function of many of genes has been clarified. This work, "Characterization of N-demethyllincomycin-methyltransferase", is focused on the study of the final step of lincomycin biosynthetic pathway - the methylation of nitrogen atom from the pyrollo ring of the propylproline unit of the N-demethyllicomycin (NDL). The aim of this work was the characterization of the protein LmbJ, catalysing this final biosynthetic step. All the experiments were provided for the enzyme LmbJ with N-terminal histidine tag, which had been prepared by the heterologous expression in E.coli cells. The pH and temperature optimum was determined as well as the Michaelis constants for both substrates of the reaction - N-demethyllincomycin and S-adenosyl methionine (SAM - a methyl group donor). With the exception of the pH optimum, all specified parameters have markedly differed from the data published for the enzyme isolated from the natural source. Based on the comparison of electron microscopy, blue native gel electrophoresis and gel filtration results, the hypothetical model of the LmbJ quarternary structure was created. Majority of methyltranserases, so far described occure in...
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Project management with the specifics of tourism
Petříčková, Kateřina ; Potluka, Oto (advisor) ; Švecová, Lenka (referee)
The thesis focuses on issues of project management and the project life cycle in tourism. It answers the question what specifics are reflected in projects financed by the European Union in the tourism sector. The thesis evaluated the benefits of selected projects financed by EU funds for the development of tourism and the development of the Czech Republic through the tourism sector.
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