Residual restoration of DNA lesions in Deinococcus radiodurans mutants indicate presence of a bypass UV-repair process

The differing UV-susceptibility and UV-damage repair capability of the Deinococcus radiodurans strains and the hypothesis of a bypass repair system have been investigated. The results obtained provide evidence that UV radiation engenders synergistic effects in combination with other stressors like temperature, humidity, desiccation and vacuum. A post-0.5 h-recovery phase was sufficient for wild-type strain to repair up to 80% of the total induced DNA photoproducts. Nucleotide excision repair (NER) is given priority over homologeous recombination repair (HR), based on the fact that 1R1A (recA) resumed repair of bipyrimidine dimers but UVs78 (uvrA-1 uvsE) did not repair any photoproduct type. Not only genetic equipment but also the applied wavelengths influence D. radiodurans' repair efficiency, especially polychromatic UV radiation enables the UV-sensitive class to repair the UV-induced lesions and retain their vitality. Hence, a further pathway must be present that can repair both photoproduct classes. The proposed core genes of the novel bypass system are DR2438, DR2439, DR2441 and DR2444 as well as DR2445, DR2446. Whereas the assertion that DR1200 and DR1891 may act as putative signal factors to initiate the NER- and HR-independent bypass still has to be verified.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Oldenburg

Year

2008

Author dc:creator

• Pogoda de la Vega, Ulrike

• [Keine Schlagwörter von Autor/in vergeben.]

Repository record source_url

http://oops.uni-oldenburg.de/749

OAI identifier oai:identifier

oai:oops.uni-oldenburg.de:749