{"created":"2023-06-19T10:26:32.216838+00:00","id":5124,"links":{},"metadata":{"_buckets":{"deposit":"b0199148-6a18-4db3-9f59-7dad3d67871c"},"_deposit":{"created_by":18,"id":"5124","owners":[18],"pid":{"revision_id":0,"type":"depid","value":"5124"},"status":"published"},"_oai":{"id":"oai:muroran-it.repo.nii.ac.jp:00005124","sets":["41:227"]},"author_link":["22745"],"item_81_date_granted_17":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2014-03-24"}]},"item_81_degree_grantor_10":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_language":"ja","subitem_degreegrantor_name":"室蘭工業大学"},{"subitem_degreegrantor_language":"en","subitem_degreegrantor_name":"Muroran Institute of Technology"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"10103","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_81_degree_name_11":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士（工学）","subitem_degreename_language":"ja"}]},"item_81_description_25":{"attribute_name":"フォーマット","attribute_value_mlt":[{"subitem_description":"application/pdf","subitem_description_type":"Other"}]},"item_81_description_7":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"生物は呼吸により酸素を体内に取り入れると，活性酸素が副産物として発生する。活性酸素には，スーパーオキシドアニオンラジカル，過酸化水素，ヒドロキシラジカルなどがあり，スーパーオキシドディスムターゼ（SOD）は，スーパーオキシドアニオンラジカルを酸素と過酸化水素に不均化させる。このSODは活性中心に存在する金属の種類によって，Cu/Zn型，Mn型，Fe型などがあり，Mn型のSOD（MnSOD）は真核生物と原核生物の両方に存在している。また，好熱菌が生産する酵素は，熱や変性剤に対する耐性が高いと知られており，好熱菌から得られるMnSODは工学的有用利用が期待できる抗酸化酵素である。本研究では，2種類の中度好熱菌Bacillus stearothermophilus（IFO12550株）およびBacillus stearothermophilus （C36株）のMnSODについて，ラウリル硫酸ナトリウム（SDS, sodium lauryl sulfate）に対する耐性を比較した。その結果，後者の耐性が高いことがわかった。これは，C36株MnSODの102番目のアミノ酸がグルタミン酸であるのに対してIFO12550株MnSODではアスパラギン酸，187番目ではそれぞれのアミノ酸はイソロイシン，バリンであり，いずれの置換も側鎖の炭素数を増加させ，C36株MnSODではタンパク質内部の疎水性の増大が，構造の安定性を引き起こしたものと考えられた。これを確かめるために，単一アミノ酸を置換したMnSODを作製し，２つのアミノ酸置換がそれぞれ耐性に関与していることが明らかになった。また，活性部位付近のアミノ酸を置換することによって，C36株MnSODのSDS耐性ではなく，活性を向上させることにも取り組んだ。その結果，C36株MnSODの164番目のバリンをヒスチジンに置換することによって活性が向上した。これは，Mn原子を保持しているアミノ酸に隣接した場所において，Mn原子の保持に働くアミノ酸であるヒスチジンに置換したことにより，Mn原子が活性部位に取り込まれやすくなったことが原因だと考えられた。これらのことは，酵素の耐性向上や活性向上において指標を示し，今後の酵素の利用を広げるものである。","subitem_description_language":"ja","subitem_description_type":"Abstract"},{"subitem_description":"When the organism takes in oxygen by breathing into the body, the active oxygen arises as a by-product. Superoxide anion radical, hydrogen peroxide and hydroxyl radical are classified as the active oxygen. Superoxide dismutase (SOD) catalyzes the conversion of the superoxide anion radical to oxygen and hydrogen peroxide. SOD can be separated into three classes based on the metal cofactors (Cu/Zn type, Mn type and Fe type). There is MnSOD in eukaryote and prokaryotic. The enzyme which thermophilic bacteria produce is known that the tolerance of enzymatic activity for heat and the denaturant is high. Also, MnSOD from thermophilic bacteria is useful antioxidant enzyme for industry.In this study, activity of MnSOD from thermophilic bacteria was measured after treatment of SDS (sodium lauryl sulfate). MnSOD of Bacillus stearothermophilus strain C36 was stable than that of Bacillus stearothermophilus strain IFO12550. There were only two differences of amino acid residues between strain C36 and strain IFO12550. Substitution position with Glu102Asp and Ile187Val were neither essential nor conserved. These inner amino acid residue changes suggested an approach to obtain more stable MnSOD.Amino acids which form the active site are conserved. In this work, an amino acid of the active site neighborhood was substituted. As a result, activity improved by substituting 164Val for His in MnSOD. It was thought that Mn atom in an active site was caught by 163His and 164His. And this wobbling His residue increased Mn modulation.","subitem_description_language":"en","subitem_description_type":"Abstract"}]},"item_81_dissertation_number_13":{"attribute_name":"学位授与番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第360号"}]},"item_81_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15118/00005115","subitem_identifier_reg_type":"JaLC"}]},"item_81_subject_9":{"attribute_name":"日本十進分類法","attribute_value_mlt":[{"subitem_subject":"465","subitem_subject_scheme":"NDC"}]},"item_81_text_12":{"attribute_name":"学位の種別","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"課程博士"}]},"item_81_text_14":{"attribute_name":"報告番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"甲第360号"}]},"item_81_text_15":{"attribute_name":"学位記番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"博甲第360号"}]},"item_81_version_type_24":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorAffiliations":[{"affiliationNameIdentifiers":[],"affiliationNames":[{"affiliationName":""}]}],"creatorNames":[{"creatorName":"渡辺, 健太","creatorNameLang":"ja"},{"creatorName":"WATANABE, Kenta","creatorNameLang":"en"},{"creatorName":"ワタナベ, ケンタ","creatorNameLang":"ja-Kana"}],"familyNames":[{},{},{}],"givenNames":[{},{},{}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-02-15"}],"displaytype":"detail","filename":"A360.pdf","filesize":[{"value":"1.3 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"A360","objectType":"fulltext","url":"https://muroran-it.repo.nii.ac.jp/record/5124/files/A360.pdf"},"version_id":"7213e512-b2ec-4c34-8a52-b37ddd4a3302"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-02-15"}],"displaytype":"detail","filename":"A360_summary.pdf","filesize":[{"value":"358.5 kB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"A360_summary","objectType":"abstract","url":"https://muroran-it.repo.nii.ac.jp/record/5124/files/A360_summary.pdf"},"version_id":"d45d6062-60c6-402d-9dd0-eb553a8c6208"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"jpn"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"好熱菌由来Mn型スーパーオキシドディスムターゼのアミノ酸置換による変性剤耐性への影響","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"好熱菌由来Mn型スーパーオキシドディスムターゼのアミノ酸置換による変性剤耐性への影響","subitem_title_language":"ja"}]},"item_type_id":"81","owner":"18","path":["227"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2014-06-26"},"publish_date":"2014-06-26","publish_status":"0","recid":"5124","relation_version_is_last":true,"title":["好熱菌由来Mn型スーパーオキシドディスムターゼのアミノ酸置換による変性剤耐性への影響"],"weko_creator_id":"18","weko_shared_id":-1},"updated":"2023-12-25T01:20:14.266873+00:00"}