Original title: Cytotoxicita a produkce sekundárních metabolitů u sinic
Translated title: Cytotoxicity and secondary metabolites of cyanobacteria
Authors: HROUZEK, Pavel
Document type: Doctoral theses
Year: 2010
Language: cze
Abstract: Cyanobacteria are well-known producers of secondary metabolites of different chemical structures and a wide range of biological functions. In the present thesis, the cytotoxic activity of cyanobacteria, originating from different habitats, was studied in order to reveal whether cytotoxicity is an environmentally dependent characteristic. In addition, the data were compared with the toxicity of these extracts to the model invertebrate Artemia salina. The obtained data suggest that cytotoxic cyanobacteria are favoured under some conditions and thus more frequent in particular localities. The majority of the studied extracts and fractions exhibited cytotoxitity to the Sp/2 cell line not accompanied by toxicity to A. salina. Moreover, in most of the strains with both activities to A. salina and Sp/2 cells the toxic effect was caused by an identical fraction. This result suggests that the toxic effect of the cyanobacterial secondary metabolites is mostly affecting basal cell metabolism rather than targeting specific organisms. In one of studied strains, Cylindrospermum sp. C24/1989, novel lipopeptides puwainaphycin F and G have been detected, isolated and their structure and biological effect have been characterized. Both of these structures interfere with eucaryotic membranes and cause a Ca2+ leakage into the cell. Subsequently, an enhanced tyrosine phosohorylation and relocalization of f-actin in the cell was observed. Lastly, the correlation between metabolite production and the reconstructed phylogeny was studied in planktonic Dolichospermopsis strains. Most of the detected compounds were found to be randomly disspersed across the reconstructed phylogeny and thus cannot be considered as good chemotaxonomic markers. This result also hampers the possible detection of toxic cyanobacteria by morphological methods or molecular detection based on the 16SrDNA gene.
Keywords: cyanobacteria; cytotoxicity; diversity; secondary metabolites production; cytotoxicita; diversita; produkce sekundárních metabolitů; sinice
Citation: HROUZEK, Pavel. Cytotoxicita a produkce sekundárních metabolitů u sinic. České Budějovice, 2010. disertační práce (Ph.D.). JIHOČESKÁ UNIVERZITA V ČESKÝCH BUDĚJOVICÍCH. Přírodovědecká fakulta

Institution: University of South Bohemia in České Budějovice (web)
Document availability information: Fulltext is available in the Digital Repository of University of South Bohemia.
Original record: http://www.jcu.cz/vskp/6934

Permalink: http://www.nusl.cz/ntk/nusl-50745


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Universities and colleges > Public universities > University of South Bohemia in České Budějovice
Academic theses (ETDs) > Doctoral theses