| Autor: |
E. Stutz, W. Löffelhardt, S. Sláviková, Rostislav Vacula, Libor Ebringer, A. Belicová, J. M. Steiner, Juraj Krajcovic |
| Rok vydání: |
1999 |
| Předmět: |
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| Zdroj: |
The Chloroplast: From Molecular Biology to Biotechnology ISBN: 9780792355779 |
| DOI: |
10.1007/978-94-011-4788-0_19 |
| Popis: |
The chloroplast system of the flagellate Euglena gracilis is particularly sensitive to various chemical and physical factors. Ofloxacin, a quinolone antibacterial chemotherapeutical, the mutagen nitrosoguanidine, as well as the hyperthermic cultivation at 33°C for 7 days, induce complete bleaching of Euglena cultures. Treatment with all those factors results in a mass degradation of E. gracilis chloroplast DNA. Significant decrease in the hybridisation signal intensity is connected with prolongation of cell exposure to the stress factors. No evidence for chloroplast genome rearrangement was obtained for chloroplasts of chemically stressed cells. On the contrary, heat induced loss of chloroplast functions is associated with partial restructurations of the chloroplast genome. Electrophoretograms of E. gracilis total RNA show distinct difference between wild type cells and bleached mutants. Bands for 23S and 16S rRNA are absent in all mutants. Subsequent hybridisation with DNA probes for nuclear encoded chloroplast proteins as Rubisco SSU and LHCPII provided identical signals for wild type cells and all mutants. However, in the case of the petJ gene for cytochrome c6 variable hybridisation signals were obtained with northern blots from an ofloxacin-bleached mutant depending on the light regime. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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