Molecular characterization of O-methyltransferases involved in isoquinoline alkaloid biosynthesis in Coptis japonica

DOI HANDLE Web Site Web Site 被引用文献2件 参考文献13件 オープンアクセス
  • MORISHIGE Takashi
    Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University Catalysis Science Laboratory, Mitsui Chemicals Inc.
  • TAMAKOSHI Masanori
    Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University
  • TAKEMURA Tomoya
    Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University
  • SATO Fumihiko
    Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University

この論文をさがす

抄録

O-Methyltransferases, which catalyze the production of small molecules in plants, play a crucial role in determining biosynthetic pathways in secondary metabolism because of their strict substrate specificity. Using three O-methyltransferase (OMT) cDNAs that are involved in berberine biosynthesis, we investigated the structure that was essential for this substrate specificity and the possibility of creating a chimeric enzyme with novel substrate specificity. Since each OMT has a relatively well-conserved C-terminal putative S-adenosyl-L-methionine-binding domain, we first exchanged the N-terminal halves of different OMTs. Among the 6 combinations that we tested for creating chimeric OMTs, 5 constructs produced detectable amounts of recombinant proteins, and only one of these with an N-terminal half of 6-OMT and a C-terminal half of 4′-OMT (64′-OMT) showed methylation activity with isoquinoline alkaloids as a substrate. Further enzymological analysis of 64′-OMT reaction product indicated that 64′-OMT retained the regio-specificity of 6-OMT. Further examination of the N-terminal region of 64′-OMT showed that about 90 amino acid residues in the N-terminal half were critical for reaction specificity. The creation of OMTs with novel reactivity is discussed.<BR><BR>(Communicated by Yasuyuki YAMADA, M.J.A.)

収録刊行物

被引用文献 (2)*注記

もっと見る

参考文献 (13)*注記

もっと見る

関連プロジェクト

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ