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Published on: February 8, 2017
シキマート経路の変異体の作成
Ningqing Ran1, K M Draths, J W Frost
1Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
Journal of the American Chemical Society
|June 4, 2004
まとめ
エンジニアリングされた酵素は,重要な代謝産物に対する競争を克服し,微生物によって生産された天然製品の生産量を増加させます. このシキマート経路の進歩は,必要性のある化合物の生合成を強化する.
科学分野:
- メタボリックエンジニアリング
- 合成生物学 合成生物学とは
- 微生物バイオテクノロジー
背景:
- シキマート経路は,微生物における芳香化合物の生成に不可欠である.
- 炭水化物フォスフォトランスフェラーゼ系によるフォスフォエノルピルバート (PEP) への競争は,微生物の生産収量を制限する.
- 3-デオキシ-d-アラビノ-ヘプトルソナート7-リン酸塩 (DAHP) 合成酵素は,PEPを消費するシキマート経路の重要な酵素です.
研究 の 目的:
- PEP競争を回避するために新しいシキマート経路変異体を設計する.
- DAHPと下流の天然製品の生産を強化する.
- 微生物の成長と代謝における設計された経路の機能性を評価する.
主な方法:
- E. coliとK. pneumoniae.から発生した2-Keto-3-deoxy-6-phosphogalactonate (KDPGal) アルドラーゼの方向進化
- 進化したKDPGalアルドラーゼ同酵素が DAHP合成活動を改善するための特徴.
- 本来のDAHP合成酵素が欠け,進化したKDPGalアルドラーゼに依存するE. coli菌株の構築と分析.
主要な成果:
- 進化したKDPGalアルドーラーゼイゾ酵素は,DAHP形成を触媒化する特異活性が4~8倍高いことを示した.
- 設計された経路は,ピルバートとd-エリトローズ4-リン酸からDAHPを成功裏に生成しました.
- 進化したKDPGalアルドラーゼを用いたE. coli構造は,微生物の成長と3-デヒドロシキマート合成を支えた.
結論:
- エンジニアリングされたシキマート経路の変種は,PEP競争を効果的に回避します.
- KDPGalアルドラーゼの誘導進化は,シキマート経路産物の微生物の産生を強化するための実行可能な戦略を提供します.
- このアプローチは,様々な天然製品の産業用生物合成を改善する可能性を秘めています.
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