碩士 / 國立海洋大學 / 生物科技研究所 / 91 / Cyclobutane pyrimidine dimers (CPDs) and 6-4photoproducts (6-4PPs) are two major types of UV-induced DNA damage and 6-4PPs are preferentially recognized by damage recognition proteins associated with nucleotide excision repair (NER). Both CPD- and 6-4PP-binding activities were detected in cell-free extracts of Chlorella pyrenoidosa by gel shift assay. Although CPDs seemed to attract more algal binding factors than 6-4PPs, a 70-kDa polypeptide was selectively captured by the 6-4PPs probe immobilized on agarose beads and no adsorption of CPD-binding polypeptides was observed. The 70-kDa polypeptide was very similar in molecular mass to a UV-damaged-DNA binding protein that had been isolated from C. pyrenoidosa extracts (Hsu, et al., 2000). A few 66 to 76 kDa weak polypeptide spots with pIs between 5.2 and 5.7 were found to bind preferentially to 6-4PPs after analyzing the adsorbed proteins by 2-D gel electrophoresis. One of the 68 to 71 kDa polypeptides might contact closely to 6-4PPs as suggested by a UV croslinking experiment. Addition of increasing concentration of NaCl to crosslinking mixtures gradually retarded the formation of covalent complexes. Affinity adsorption with a 6-4PP-specific probe should be an efficient way to search for NER damage-recognition proteins in green algae when used with advanced protein chemistry techniques.
| Identifer | oai:union.ndltd.org:TW/091NTOU0613008 |
| Date | January 2003 |
| Creators | Mei-Chu Luan, 欒媄竹 |
| Contributors | Todd Hsu, 許濤 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 74 |
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