バシロスのルビスコのようなタンパク質と光合成ルビスコとの機能的なリンク
Hiroki Ashida1, Yohtaro Saito, Chojiro Kojima
1Graduate School of Biological Sciences, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0101, Japan.
まとめ
バシルス・サブティリスのバクテリアのリブルース・ビスホスファート・カルボキシラーゼ/酸素酵素類似タンパク質 (RLP) は,メチオニンの回収経路を容易にする. Rhodospirillum rubrumからの光合成 RuBisCOは,B. subtilis RLPを機能的に置き換えることができ,保存された酵素能力を強調しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 微生物学 微生物学とは
- 酵素学 酵素学とは
背景:
- 非光合成細菌とアルカイアには,リブルース・ビスホスファート・カルボキシラーゼ/酸素酵素 (RuBisCO) に同類な遺伝子があります.
- バシルス・サブティリスのRuBisCOのようなタンパク質 (RLP) は,特徴づけられていない機能を持っています.
研究 の 目的:
- B. subtilisのルビスコ型タンパク質 (RLP) の酵素活性を調べる.
- 光合成ルビスコがメチオニン回収経路でB. subtilis RLPを機能的に置き換えることができるかどうかを判断する.
主な方法:
- 酵素活性アッセイは,B. subtilis RLP.に実施されました.
- 破壊されたRLP遺伝子を持つA B. subtilisの変異体が作成されました.
- ミュータントは,Rhodospirillum rubrum.からのRuBisCO遺伝子で補完されました.
主要な成果:
- B. subtilis RLPは2,3-ディケト-5-メチルチオペンチル-1-リン酸エノラゼ反応を触媒として識別されました.
- この反応はメチオニンの回収経路内で起こります.
- R. rubrumからの光合成 RuBisCOは,B. subtilis RLP変異体の成長欠陥を救った.
結論:
- B. subtilis RLPはメチオニンの回収経路において重要な役割を果たしています.
- 光合成ルビスコ (RuBisCO) は,細菌のメチオニン回収経路における機能的活動を保持し,多様な生物体全体で保存された酵素機能を示しています.
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