菌類のセステルペノイド生物合成における前例のないサイクルモードのゲノムベースの発見
Masahiro Okada1, Yudai Matsuda1, Takaaki Mitsuhashi1
1Graduate School of Pharmaceutical Sciences, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|July 23, 2016
まとめ
研究者はキアヌラテンという 新種のセステルテルペンを 菌類の酵素EvQSを用いて発見しました 独特の生物合成には複雑な再編成が含まれ,知られているセステルペノイドの多様性を拡大します.
科学分野:
- 自然製品化学
- 酵素学
- 生物合成
背景:
- ゲラニルファルネシルピロフォスファート (GFPP) から派生したセステルペノイドは,構造が多様な希少なテルペノイドである.
- 生物合成経路に関する知識が限られているため,多くのセステルペノイドの支架は未発見のままである.
研究 の 目的:
- 菌類のセステルペン合成酵素EvQSの特徴を明らかにする.
- 新しいセステルペノイドの構造と生物合成を発見し,解明する.
主な方法:
- ゲノムマイニングで セステルテルペン合成剤を特定する
- GFPPとEvQSを用いた酵素測定法
- 結果となるセステルテルペンの構造の解明.
- サイクル化過程のメカニズム研究
主要な成果:
- 菌類のセステルペン合成酵素EvQSを特徴づけました.
- 独特で混雑した炭素骨格を持つ新しいセステルテルペン,キアヌラテン (1) が得られた.
- キアンヌラチン酸 (2) はキアンヌラチンの酸化産物として特定された.
- キアヌラテンの生物合成には,複数の水素シフトとC−C結合の移行による前例のないサイクルモードが含まれています.
結論:
- EvQSは,新しい生物合成経路を通じてキアヌラテンの形成を触媒化する.
- この発見は,セステルペノイドの既知の構造の多様性を拡大します.
- この発見は,テルペンの生体合成の進化の洞察を与えてくれます.
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