ツゲ ヒデアキ   TSUGE HIDEAKI
  津下 英明
   所属   京都産業大学  生命科学部 先端生命科学科
   職種   教授
言語種別 英語
発行・発表の年月 2008/03
形態種別 研究論文
査読 査読あり
標題 Structure of L-aspartate oxidase from the hyperthermophilic archaeon Sulfolobus tokodaii
執筆形態 その他
掲載誌名 BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS
出版社・発行元 ELSEVIER SCIENCE BV
巻・号・頁 1784(3),pp.563-571
著者・共著者 Haruhiko Sakuraba,Kazunari Yoneda,Issaku Asai,Hideaki Tsuge,Nobuhiko Katunuma,Toshihisa Ohshima
概要 The crystal structure of the highly thermostable L-aspartate oxidase (LAO) from the hyperthermophilic archaeon Sufolobus tokodaii was determined at a 2.09 angstrom resolution. The factors contributing to the thermostability of the enzyme were analyzed by comparing its structure to that of Escherichia coli LAO. Like E. coli LAO, the S. tokodaii enzyme consists of three domains: an FAD-binding domain, an alpha+beta capping domain, and a C-terminal three-helix bundle. However, the situation of the linker between the FAD-binding domain and C-terminal three-helix bundle in S. tokodaii LAO is completely different from that in E. coli LAO, where the linker is situated near the FAD-binding domain and has virtually no interaction with the rest of the protein. In S. tokodaii LAO, this linker is situated near the C-terminal three-helix bundle and contains a beta-strand that runs parallel to the C-terminal strand. This results in the formation of an additional beta-sheet, which appears to reduce the flexibility of the C-terminal region. Furthermore, the displacement of the linker enables formation of a 5-residue ion-pair network between the FAD-binding and C-terminal domains, which strengthens the interdomain interactions. These features might be the main factors contributing to the high thermostability of S. tokodaii LAO. (C) 2008 Elsevier B.V. All rights reserved.
DOI 10.1016/j.bbapap.2007.12.012
ISSN 1570-9639/0006-3002