Identificación y caracterización de genes implicados en el metabolismo de esteroles en Tetrahymena mediante análisis bioinformático, expresión heteróloga y análisis transcriptómico
The ciliate Tetrahymena thermophila does not synthesize nor require sterols for growth, although synthesizes tetrahymanol, unlike other ciliates which do not produce tetrahymanol and are auxotrophic for sterols. Some ciliates can incorporate sterols and modify them. Tetrahymanol and sterol metabolic...
Guardado en:
| Autor principal: | |
|---|---|
| Otros Autores: | |
| Formato: | Tesis doctoral acceptedVersion |
| Lenguaje: | Español |
| Publicado: |
Facultad de Farmacia y Bioquímica
2015
|
| Materias: | |
| Acceso en línea: | http://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=posgraafa&cl=CL1&d=HWA_1169 http://repositoriouba.sisbi.uba.ar/gsdl/collect/posgraafa/index/assoc/HWA_1169.dir/1169.PDF |
| Aporte de: |
| Sumario: | The ciliate Tetrahymena thermophila does not synthesize nor require sterols for growth, although synthesizes tetrahymanol, unlike other ciliates which do not produce tetrahymanol and are auxotrophic for sterols. Some ciliates can incorporate sterols and modify them. Tetrahymanol and sterol metabolic pathways were analyzed in silico, revealing the presence of the complete tetrahymanol synthesis pathway in Tetrahymena, with enzymes from diverse origins, but incomplete in other ciliates analyzed. Moreover, the gene expression level in response to sterol was investigated in T. thermophila showing the regulation of the metabolic pathway of tetrahymanol and sterols. T. thermophila transforms some sterols through four enzymatic activities, C-5, C-7 and C-22 desaturations and C-24 de-ethylation. C-5 sterol desaturase (Des5Ap) is a cytochrome b5 / cytochrome b5 reductase dependent, while the C-7 sterol desaturase (Des7p) electron donor system is unknown. Functionality and conservation of electron donors of both were analyzed by expressing Des5Ap in Saccharomyces cerevisiae and Des7p in Spodoptera frugiperda cells, revealing that both enzymes are functional despite the evolutionary distance, and also the electron donor are preserved systems. |
|---|