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 2009/10
形態種別 研究論文
査読 査読あり
標題 Structural basis for the Helicobacter pylori-carcinogenic TNF-alpha-inducing protein
執筆形態 その他
掲載誌名 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
出版社・発行元 ACADEMIC PRESS INC ELSEVIER SCIENCE
巻・号・頁 388(2),pp.193-198
担当区分 筆頭著者,責任著者
著者・共著者 Hideaki Tsuge,Toshiharu Tsurumura,Hiroko Utsunomiya,Daisuke Kise,Takashi Kuzuhara,Tatsuro Watanabe,Hirota Fujiki,Masami Suganuma
概要 Stomach cancer is strongly associated with infection by Helicobacter pylori. In 2005, we identified a new H. pylori gene encoding a TNF-alpha inducing protein (Tip alpha) that acts as a carcinogenic factor. Tip alpha is secreted from H. pylori as a homodimer whose subunits are linked by disulfide bonds. We also characterized a Tip alpha deletion mutant (del-Tip alpha) that lacks the N-terminal six amino acid residues (LQACTC), including two cysteines (C5 and C7) that form disulfide bonds, but nonetheless shows a weak ability to induce TNF-alpha expression. Here we report that del-Tip alpha has a novel elongated structure containing a 40-angstrom-long alpha helix, and forms a heart-shaped homodimer via non-covalent bonds. Moreover, their circular dichroism spectra strongly suggest that the structures of the del-Tip alpha and Tip alpha homodimers are very similar. del-Tip alpha's unique mode of dimer formation provides important insight into protein-protein interactions and into the mechanism underlying the carcinogenicity of H. pylori infection. (C) 2009 Elsevier Inc. All rights reserved.
DOI 10.1016/j.bbrc.2009.07.121
ISSN 0006-291X/1090-2104