{"_buckets": {"deposit": "afa60141-b9b8-4717-b6e3-8b4d7f200ed6"}, "_deposit": {"created_by": 1, "id": "1250", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "1250"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00001250", "sets": ["24"]}, "author_link": ["0", "0", "0"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2006-09-29", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "李, 江"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "リ, ジャン"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "2006-09-29"}]}, "item_1_degree_grantor_5": {"attribute_name": "学位授与機関", "attribute_value_mlt": [{"subitem_degreegrantor": [{"subitem_degreegrantor_name": "総合研究大学院大学"}]}]}, "item_1_degree_name_6": {"attribute_name": "学位名", "attribute_value_mlt": [{"subitem_degreename": "博士（理学）"}]}, "item_1_description_1": {"attribute_name": "ID", "attribute_value_mlt": [{"subitem_description": "2006534", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "　Ultraviolet light radiation in the wavelength range between 260 and 320 nm causes\u003cbr /\u003edamage to DNA by forming the dimerization of adjacent pyrimidines in the same DNA\u003cbr /\u003estrand. This covalentry linked dimer influences the replication and transcription, and leads\u003cbr /\u003eto cell death or skin cancer.　Most (70-80%) of UV-induced DNA lesions is cyclobutane\u003cbr /\u003epyrimidine dimer (CPD) and, a lesser extent (20-30%) is (6-4) photoproduct.  These two\u003cbr /\u003emajor types of UV-damaged DNA are repaired under illumination with near-UV/visible\u003cbr /\u003elight by CPD photolyase and (6-4) photolyase, respectively. The both photolyases contain\u003cbr /\u003eflavin adenine dinucleotide (FAD) as an essential cofactor for DNA repairing. The structure\u003cbr /\u003eand catalytic mechanism of CPD photolyase have been extensively studied.　However, its\u003cbr /\u003edetailed structure of the active site containing CPD is uncertain until now. The structure of \u003cbr /\u003e(6-4) photolyase is less well studied. The genes for this enzyme exhibit a sequence\u003cbr /\u003esimilarity to CPD photolyase, especially in the FAD binding sites. Such high similarity\u003cbr /\u003eindicates a similar structure and reaction mechanism in two photolyases. Unexpectedly,\u003cbr /\u003e(6-4) photolyase presents a much lower quantum yield compared to that of CPD photolyase,\u003cbr /\u003eindicating the differences in structure and reaction mechanism between (6-4) and CPD\u003cbr /\u003ephotolyase. Such precise differences between CPD photolyase and (6-4) photolyase\u003cbr /\u003eregarding substrate binding and DNA repair needs to be clarified.\u003cbr /\u003e　To investigate the unclear structure and environment of the active site in (6-4)\u003cbr /\u003ephotolyase, we measured resonance Raman spectra of (6-4) photolyase having neutral\u003cbr /\u003esemiquinoid and oxidized forms of FAD, which were selectively intensity enhanced by\u003cbr /\u003eexcitations at 568.2 and 488.0 nm, respectively. DFT calculations were carried out for the\u003cbr /\u003efirst time on the neutral semiquinone. The marker band of a neutral semiquinone at 1606\u003cbr /\u003ecm\u003csup\u003e-1\u003c/sup\u003e in H\u003csmall\u003e2\u003c/small\u003eO. whose frequency is the lowest among various flavoenzymes, apparently splits\u003cbr /\u003einto two comparable bands at 1594 and 1608 cm\u003csup\u003e-1\u003c/sup\u003e in D\u003csmall\u003e2\u003c/small\u003eO, and similarly that at 1522 cm\u003csup\u003e-1\u003c/sup\u003e in \u003cbr /\u003eH\u003csmall\u003e2\u003c/small\u003eO does into three bands at 1458, 1508, and 1536 cm\u003csup\u003e-1\u003c/sup\u003e in D\u003csmall\u003e2\u003c/small\u003eO. This D\u003csmall\u003e2\u003c/small\u003eO effect was \u003cbr /\u003erecognized only after being oxidized once and photoreduced to form a semiquinone again,\u003cbr /\u003ebut not by simple H/D exchange of solvent. Some Raman bands of the oxidized form were\u003cbr /\u003eobserved at significantly low frequencies (1621, 1576 cm\u003csup\u003e-1\u003c/sup\u003e)and with band splittings\u003cbr /\u003e(1508/1493, 1346/1320 cm\u003csup\u003e-1\u003c/sup\u003e). These Raman spectral characteristics indicate strong H-bonding\u003cbr /\u003einteractions (at N5-H, N1), a fairly hydrophobic environment, and an electron-lacking feature in\u003cbr /\u003ebenezene ring of the FAD cofactor, which seems to specifically control the reactivity of (6-4) photolyase.\u003cbr /\u003e　To clarify the structure of active site upon substrate binding and the mechanism of DNA repair, we\u003cbr /\u003eexamined the resonance Raman spectra of complexes between damaged DNA and the neutral\u003cbr /\u003esemiquinoid and oxidized forms of (6-4) and CPD photolyases. The marker band for a neutral\u003cbr /\u003esemiquinoid flavin and band I of the oxidized flavin, which are derived from the vibrations of the\u003cbr /\u003ebenzene ring of flavin adenine dinucleotide (FAD), were shifted to lower freauencies upon binding of \u003cbr /\u003edamaged DNA by CPD photolyase but not by (6-4) photolyase, indicating that CPD interacts with the\u003cbr /\u003ebenzene ring of FAD directly but that (6-4) photoproduct does not. Bands II and VII of the oxidized\u003cbr /\u003eflavin and the 1398/1391 cm\u003csup\u003e-1\u003c/sup\u003e bands of the neutral semiquinoid flavin, which may reflect the bending of\u003cbr /\u003ethe U-shaped FAD, were altered upon substrate binding suggesting that CPD and (6-4) photoproduct\u003cbr /\u003einteract with the adenine ring of FAD, When substrate is bound, there is an upshiftesd 1528 cm\u003csup\u003e-1\u003c/sup\u003e band of\u003cbr /\u003ethe neutral semiquinoid flavin in CPD photolyase, indicating a weekend hydrogen bond at N5-H of\u003cbr /\u003eFAD, and in (6-4) photolyase, band X is downshifted, indicating a strengthened hydrogen bond at N3-H\u003cbr /\u003eof FAD. These Raman spectra led us to conclude that the two photolyases have different electron \u003cbr /\u003etransfer mechanisms as well as different hydrogen bonding environments, which account for the higher\u003cbr /\u003eredox potential of CPD photolyase.\u003cbr /\u003e　This work revealed that the FAD in (6-4) photolyase is characterized by an electron\u003cbr /\u003elocalized structure, and binds to the protein in a fairly hydrophobic and strong hydrogen \u003cbr /\u003ebonding environment, Specially, a stronger H-bonding at N5-H of FAD was identified for \u003cbr /\u003e(6-4) photolyase, which may result in the low quantum yield for DNA-repair of this\u003cbr /\u003eenzyme. Besides, UV-damaged DNA contacts the benzene ring of FAD only in CPD\u003cbr /\u003ephotolyase and the adenine ring of FAD in both photolyases. These structures indicate that\u003cbr /\u003e the election transfer during DNA -repair between isoalloxazine and UV-damaged DNA in \u003cbr /\u003eCPD photolyase is direct, whereas that in (6-4) photolyase is not direct and bridged by\u003cbr /\u003eadenine.", "subitem_description_type": "Other"}]}, "item_1_description_18": {"attribute_name": "フォーマット", "attribute_value_mlt": [{"subitem_description": "application/pdf", "subitem_description_type": "Other"}]}, "item_1_description_7": {"attribute_name": "学位記番号", "attribute_value_mlt": [{"subitem_description": "総研大甲第1014号", "subitem_description_type": "Other"}]}, "item_1_select_14": {"attribute_name": "所蔵", "attribute_value_mlt": [{"subitem_select_item": "有"}]}, "item_1_select_8": {"attribute_name": "研究科", "attribute_value_mlt": [{"subitem_select_item": "先導科学研究科"}]}, "item_1_select_9": {"attribute_name": "専攻", "attribute_value_mlt": [{"subitem_select_item": "22 光科学専攻"}]}, "item_1_text_10": {"attribute_name": "学位授与年度", "attribute_value_mlt": [{"subitem_text_value": "2006"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "LI, Jiang", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_files": {"attribute_name": "ファイル情報", "attribute_type": "file", "attribute_value_mlt": [{"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 0, "filename": "甲1014_要旨.pdf", "filesize": [{"value": "312.3 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 312300.0, "url": {"label": "要旨・審査要旨", "url": "https://ir.soken.ac.jp/record/1250/files/甲1014_要旨.pdf"}, "version_id": "a4884a63-7dd4-4707-9690-2d6fd958b946"}, {"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 1, "filename": "甲1014_本文.pdf", "filesize": [{"value": "11.1 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 11100000.0, "url": {"label": "本文", "url": "https://ir.soken.ac.jp/record/1250/files/甲1014_本文.pdf"}, "version_id": "2d1248dc-9951-4550-87c4-eca306756954"}]}, "item_language": {"attribute_name": "言語", "attribute_value_mlt": [{"subitem_language": "eng"}]}, "item_resource_type": {"attribute_name": "資源タイプ", "attribute_value_mlt": [{"resourcetype": "thesis", "resourceuri": "http://purl.org/coar/resource_type/c_46ec"}]}, "item_title": "Resonance Raman Studies on Reaction Mechanism of Photolyases: Structural Characteristics of the Active Site and Photo-repair Mechanism of UV-damaged DNA", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Resonance Raman Studies on Reaction Mechanism of Photolyases: Structural Characteristics of the Active Site and Photo-repair Mechanism of UV-damaged DNA"}, {"subitem_title": "Resonance Raman Studies on Reaction Mechanism of Photolyases: Structural Characteristics of the Active Site and Photo-repair Mechanism of UV-damaged DNA", "subitem_title_language": "en"}]}, "item_type_id": "1", "owner": "1", "path": ["24"], "permalink_uri": "https://ir.soken.ac.jp/records/1250", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-02-22"}, "publish_date": "2010-02-22", "publish_status": "0", "recid": "1250", "relation": {}, "relation_version_is_last": true, "title": ["Resonance Raman Studies on Reaction Mechanism of Photolyases: Structural Characteristics of the Active Site and Photo-repair Mechanism of UV-damaged DNA"], "weko_shared_id": -1}