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Autophagy as a mechanism of adaptation the yeast
Zieglerová, Leona ; Váchová, Libuše (advisor) ; Zikánová, Blanka (referee)
Autophagy is a degradation pathway, conserved from yeast to mammals. The uniqueness of this pathway lies in its function, it is applied in the cell especially under the adverse conditions. It helps the cell to deliver essential nutrients for life, it removes the damaged or superfluous organelles, protein aggregates and helps with recycling and maintains a constant inner environment. These functions can prolong cell life and the cells survive the adverse conditions. Autophagy may induce the programmed cell death type II. This paper describes the basic of autophagy machinery, regulation and influence of yeast autophagy to adapt to the stressful conditions. Understanding the mechanism and regulation of autophagy in yeast may help with the study of autophagy in mammals. In mammals, this degradation pathway disorders cause many diseases (especially neurodegenerative), autophagy also effects the formation of tumors. Powered by TCPDF (www.tcpdf.org)
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Mycobacterium smegmatis biofilm formation om glass and zirkonia beads-proteomic study
Sitařová, Barbora ; Weiser, Jaroslav (advisor) ; Zikánová, Blanka (referee)
Biofilms represent universal strategy for bacterial survival. Living in form of biofilms, bacteria acquire wide range of advantages over planktonically growing cultures. It can be assumed that nearly 99% of world bacterial population is living in form of biofilms. There are benefits and drawbacks associated with bacterial biofilms for mankind. Life in biofilms makes pathogens more effective and persistent through higher antibiotic resistance and helps them to hide before immune system of the host. Mycobacteria, which are capable of forming biofilms on variety of surfaces, differ from most of other bacteria by unique composition of their cell wall. It provides them with high resistance against physical or chemical damage. This is one of the reasons for considering Mycobacterium tuberculosis as a highly potent pathogen. The studies of mycobacterial biofilms are motivated by effort to improve or find new therapeutic methods. This work is aimed at morphological and proteomic comparative analyses of biofilms obtained from Mycobacterium smegmatis grown on surface of glass and silica/zirconium beads, on liquid medium surface or grown submerged in shaken planktonic culture. We have developed technique for preparation of "floating" biofilm sample to be observed in SEM. We have shown that the growth of...
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Analysis of gene expression in maternal and fetal tissues exposed to cigarette smoke
Fejglová, Kamila ; Bruchová, Hana (advisor) ; Zikánová, Blanka (referee)
Despite widespread awareness of the adverse health effects of smoking, pregnant women expose themselves to this factor (firsthand and/or secondhand smoke). Cigarette smoke exposure during pregnancy increases the risk of preterm delivery, abortion or newborn sudden death syndrom. To study molecular mechanisms of cigarette smoke exposure in tissues of pregnant women and their newborns, we employed genomic approach and assessed gene expression profiles in leukocytes from maternal peripheral blood and umbilical cord blood and in placenta as well. Gene expression profiles of these tissues were determined by Illumina HumRef8 v3 expression chips that enable analysis of 23 811 coding, annotated transcripts. Microarray data were normalized using the quantile method. Differential gene expression was analyzed using moderated t-statistic. A linear model was fitted for each gene given a series of arrays using lmFit function. Multiple testing correction was performed using the Benjamini and Hochberg method. Comparative analysis of gene expression profiles between smokers (N=23) and non-smokers (N=62) revealed many deregulated genes, demonstrating a negative effect of cigarette smoke on transcriptome of the tested tissues. In peripheral blood of smokers, we detected overexpression of these genes; e.g. IFI27, IFIT1L,...
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Mutational analysis of manumycin antibiotics biosynthetic routes
Kolek, Jan ; Petříček, Miroslav (advisor) ; Zikánová, Blanka (referee)
Mutational analysis of manumycin antibiotics biosynthetic routes The manumycin antibiotics are secondary metabolites, which come from a big group of polyketide metabolites. They are produced by bacteria from genus Streptomyces. Manumycin antibiotics are characterized by two linear polyketide chains, which are connected to a central mC7N moiety. The lower chain is often terminated by the C5N moiety. Manumycin metabolites show many biological activities. They have antimicrobial activity, especially against gram-positive bacteria. Next, they posses antifungal, insecticidal or antiinflamatory activities. Manumycins are also potentional anticancer agents. In order to prepare these compounds by the fermentation, the detailed knowledge of their biosynthetic routes is required. Mutational analysis is based on techniques of genetic engineering. Mutational analysis is a useful pool for analysis of biosynthetic pathways of secondary metabolites and the genes, which are involved in these pathways. This knowledge is essential for application of combinatorial biosynthesis for the design of new metabolites. The new hybrid compound could be used in future as new antibiotics or anticancer drugs. Keywords: manumycin, polyketide, streptomyces, asukamycin
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Molecular characterization of resistance to MLSb antibiotics in Staphylococcus aureus and SCV Staphylococcus aureus strains of cystic fibrosis patients
Vařeková, Eva ; Melter, Oto (advisor) ; Zikánová, Blanka (referee)
Cystic fibrosis (CF) is the most common autosomal recessive genetic disorder in Caucasians. Lower respiratory tract of CF patients is colonized by specific bacteria, often leading to chronic infection and lung tissue damage. In this thesis we characterized 338 isolates of S. aureus from 92 Czech CF patients isolated in 2011-2013. Using spa typing and PFGE we detected high clonal heterogenity of this collection with the exception of MRSA strains (resistant to oxacillin; 5% prevalence) which were clonally related. The prevalence of S. aureus MLSB resistance in our collection was high (69 %), which is a serious problem due to common usage of these antimicrobials in clinical practice. A half of the MLSB resistant strains lacked any known determinant of this resistance (ermA, ermC, ermT, msrA). Sequencing of the ribosomal genes revealed a high number of S. aureus strains carrying target site mutations resulting in MLSB resistance (37 %). This is new important information about the staphylococcal strains associated with chronic infections in Czech Republic. Focusing on mutability of analysed strains, we also detected several strains with point mutations or deletions in their mutator genes mutS a mutL. Hypermutability could be responsible for the high rate of ribosomal mutations and for the presence of...
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Interactions of two nearby bacterial colonies - the effect of signaling molecules and nutrients on the colony growth
Dobřemyslová, Mária ; Fišer, Radovan (advisor) ; Zikánová, Blanka (referee)
Between neighbouring bacterial colonies of the same species there occur mutual interactions influencing their growth (both size and pattern). Effects of these interactions on the growth can be both negative and positive, and can change in the course of development of colonies. The primary cause of mutual influence is often competion for available sources of nutrients, production of wastes, and production and utilization of public goods. The intensity of influence depends on external factors like mutual distance of colonies, medium composition and rigidity, or possibility of mutual signal molecule exchange. In this bachelor's thesis there are described known mechanisms of intraspecies interactions that may be of some importance in communication between two colonies. In more detail there are described three particular cases of influence of two nearby colonies that have been up to now studied more intensively. Further on, there have been summarized methods of measuring the sizes of colonies and algorythms applicable to evaluation of mutual influence of nearby colonies.
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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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