Mutational Effects on O6-Methylguanine-DNA Methyltransferase from Hyperthermophile: Contribution of Ion-Pair Network to Protein Thermostability

• Nishikori Shingo

  School of Materials Science, Japan Advanced Institute for Science and Technology

• Shiraki Kentaro

  School of Materials Science, Japan Advanced Institute for Science and Technology

• Yokota Kiyonobu

  School of Materials Science, Japan Advanced Institute for Science and Technology

• Izumikawa Naoshige

  School of Materials Science, Japan Advanced Institute for Science and Technology

• Fujiwara Shinsuke

  Department of Bioscience, School of Science and Technology, Kwansei-Gakuin University

• Hashimoto Hiroshi

  Science of Biological Supermolecular Systems, Graduate School of Integrated Science, Yokohama City University

• Imanaka Tadayuki

  Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University

• Takagi Masahiro

  School of Materials Science, Japan Advanced Institute for Science and Technology

書誌事項

タイトル別名

• Mutational Effects on <i>O</i>⁶-Methylguanine-DNA Methyltransferase from Hyperthermophile: Contribution of Ion-Pair Network to Protein Thermostability

抄録

Ion pairs have been considered to be general stabilizing factors in hyperthermophilic proteins, but the present experimental data cannot fully explain how ion pairs and ion-pair networks contribute to the stability. In this paper, we show experimental evidence that not all of the internal ion pairs contribute to the thermal and thermodynamic stability, using O⁶-methylguanine-DNA methyltransferase from Thermococcus kodakaraensis KOD 1 (Tk-MGMT) as a model protein. Of three mutants in which an inter-helical ion pair was disrupted, only one mutant (E93A) was shown to be destabilized. ΔG of E93A was lower by _??_4 kJ mol^-1 than that of the wild type, and E93A unfolded one order of magnitude faster than did the wild type and other variants. Glu 93 has unique properties in forming an ion-pair network that bridges the N- and C-terminal domains and connects three helices in the protein interior.

収録刊行物

• The Journal of Biochemistry

  The Journal of Biochemistry 135 (4), 525-532, 2004

  社団法人 日本生化学会

キーワード

• Archaea
• ion-pair network
• hyperthermostable protein
• thermodynamics
• thermal stability

詳細情報

• CRID: 1390001204966404096
• NII論文ID: 130003534692
• NII論文ID: 10016199524
• NII書誌ID: AA00694073
• DOI: 10.1093/jb/mvh061
• COI: 1:CAS:528:DC%2BD2cXltFCgtLg%3D
• ISSN: 17562651
• ISSN: 0021924X
• NDL書誌ID: 6931275
• PubMed: 15115778
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I6931275
• Web Site: http://academic.oup.com/jb/article-pdf/135/4/525/2904179/mvh061.pdf
• 本文言語コード: en
• データソース種別:
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  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
  • KAKEN
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