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Evolution of eukaryotic ABC transporters
Žárský, Vojtěch ; Tachezy, Jan (advisor) ; Doležal, Pavel (referee)
In the past twenty years there has been a lot of research done on ABC transporters. This group of membrane transporters was recognized as highly important due to its ubiquity in living organisms and due to the involvement of some of the ABC transporters in multidrug resistance of cancer cells and pathogens against chemotherapeutics. This medical aspect of ABC transporters was naturally the most important one for the majority of researchers. On the other hand, the biological aspects and evolution of many ABC transporters remained untouched. In this work I give an overview of ABC transporters of parasitic protozoa and focus on the evolutionary aspect of eukaryotic transporters and on mitochondrial ABC transporters, which are the most conserved ones among eukaryotic ABC transporters.
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Proteomic Analysis of Trichomonas vaginalis hydrogenosone
Campo Beltran, Neritza ; Tachezy, Jan (advisor) ; Nohýnková, Eva (referee) ; Yarlett, Nigel (referee)
Trichomonas vaginalis is a human pathogen that affects annually approximately 258 million people worldwide. This parasite possesses organelles of mitochondrial origin called hydrogenosomes, which generate ATP under anaerobic conditions. The identification of the protein content at the subcellular level may provide new targets for antiparasitic drugs developments as well as it contributes for our understanding of the organelles function and evolution. The availability of protocols for organelles purification and the complete genome sequence allow the study of the organellar proteomes using mass spectrometry and bioinformatics, providing a powerful strategy that combine cell biology and proteomics. In our research, we used several approaches to identify the protein composition in hydrogenosomes and mitosomes. We performed transcriptomic and proteomic analysis to investigate the molecular responses of Trichomonas vaginalis upon iron availability. Furthermore, the changes in the proteome during the development of metronidazole resistance were also studied. The organelles separated by differential and Optiprep-sucrose gradient centrifugation were analyzed with nano- RP-HPLC/MALDI-TOF/TOF. We also used Triton X-114 phase partitioning to separate membrane proteins and iTRAQ technique to label the peptides...
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Evolution of hydrogenosomes: adaptation of free living protists Mastagamoeba balamuthi and Naegleria gruberi to oxygen-poor environment
Nývltová, Eva ; Tachezy, Jan (advisor) ; TIELENS, Aloysius Gerard Marie (referee) ; Markoš, Anton (referee)
Various protists from different eukaryotic groups are able to live in the oxygen-poor niches. Their metabolic adaptation to anaerobiosis is usually associated with loss of the typical mitochondrial functions, including the tricarboxylic acid cycle and oxidative phosphorylation. Anaerobic forms of mitochondria generate ATP exclusively by the substrate level phosphorylation in the hydrogen-producing hydrogenosomes, or the ATP synthesis is completely lost as observed in mitosomes. Consequently, the proteomes of such organelles are considerably reduced. It is a question of debate whether the anaerobic forms of mitochondria evolved directly from premitochondrial organelles that might be present in ancient anaerobic eukaryotes or during the secondary adaptation of aerobic eukaryotes to anaerobic niches. The protist from super group Amoebozoa, Mastigamoeba balamuthi, is very attractive for study of mitochondria evolution, because it is closely related with two very different organisms: (i) the aerobic, free-living slime molds such as Dictyostelium that possesses classical aerobic mitochondria, as well as (ii) the anaerobic parasite Entamoeba histolytica that contains mitosomes, the most reduced form of mitochondria. The mitochondria derived organelles in anaerobic, free-living M. balamuthi could represent...
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FeS cluster assembly in cytosol of Trichomonas vaginalis
Stojanovová, Darja ; Tachezy, Jan (advisor) ; Šuťák, Róbert (referee)
Iron-sulfur (FeS) cluster assembly is extensively studied in model organisms, e.g. Saccharomyces cerevisiae, Homo sapiens, and more recently in Trypanosoma brucei. However, little is known about FeS assembly in divergent anaerobic organisms such as Trichomonas vaginalis, which parasites in the human urogenital tract. This parasitic protist possesses anaerobic form of mitochondria, the hydrogenosome, in which some component of FeS cluster assembly machinery (ISC) has been identified, whereas the cytosolic CIA pathway has not been studied so far. Our work deals mainly with TvIscU, a component of ISC pathway, and T. vaginalis CIA pathway. We suggest that both hydrogenosomal and cytosolic FeS cluster assembly pathways of this parasite differ from typical models. We examined possible ISC-CIA relationship. Next, we found homologues for several key components involved CIA machinery, namely Nbp35, Cfd1, Nar1, Cia1 and Cia2. However, we did not identify any homologous proteins to Tah18, Dre2 and Mms19. We expressed identified proteins with HA-tag and localized them by cell fractionation and immunofluorescence microscopy in T. vaginalis. Finally, we immunoprecipitated two Cfd1 paralogues, TvCfd1A and TvCfd1B to search for their interacting partners. The results suggest that these two paralogues interact with...
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Pathogenic trichomonads in cats and dogs
Vobořilová, Pavlína ; Tachezy, Jan (advisor) ; Hampl, Vladimír (referee)
Trichomonads are anaerobic flagellated protists that are either parasites or commensals. They frequently inhabit digestive, respiratory, and urogenital tracts of vertebrates, including domestic cats and dogs. In these hosts, four trichomonad species has been described: Tetratrichomonas canistomae and Tetratrichomonas felistomae that are commensals of the host oral cavity; Pentatrichomonas hominis, a commensal of intestinal tract that could be found in dogs and cats but also in other mammals including humans; and pathogenic Tritrichomonas foetus that causes, in addition to cattle infection, feline intestinal trichomonosis. Although, trichomonads in dogs and cats are probably of cosmopolitan distribution we have no information about their presence in Czech Republic. The first aim of this study was to distinguish types of trichomonads present in the oral cavity of dogs and cats and to get preliminary epidemiological data. The second aim was to demonstrate the presence of Tritrichomonas foetus in cats and dogs in the Czech Republic and to identify potential risk factors for the disease. Cultivation and nested PCR were used to determine the presence of trichomonads in dogs and cats. Sequencing and phylogenetic analysis based on ITS1-5.8rRNA-ITS2 gene sequence was used to identify species of isolated...
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