酵母におけるビタミンB6の生物合成:グルコースの組み込みパターン
R N Gupta1, T Hemscheidt, B G Sayer
1Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1.
Journal of the American Chemical Society
|November 15, 2001
まとめ
イーストのビタミンB6の炭素骨格は,E. coliよりも異なる形で発生します. イーストは,ピリドキサミンとリボースの合成のために,一般的なグルコース由来の中間物質を使用します.
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
- 代謝経路について
背景:
- ビタミンB6 (ピリドキシンとピリドキサミン) は,多くの代謝プロセスに不可欠です.
- 異なる生物体におけるビタミンB6の生物合成を理解することは,代謝工学と医薬品の応用において極めて重要です.
- 以前の研究では,Escherichia coli.におけるビタミンB6の生物合成経路が確立されました.
研究 の 目的:
- ビタミンB6の炭素骨格の起源を2つの酵母種Saccharomyces cerevisiaeとCandida utilis.で明らかにする.
- 酵母におけるビタミンB6の生物合成経路を,Escherichia coliで以前に特定された経路と比較する.
主な方法:
- サッカロミセス・セレヴィセアとカンジダ菌のインキュベーションは, (13) Cで標識されたD-グルコースを用いて行う.
- 酵母からピリドキサミンジヒドロクロライドの分離と浄化.
- (13) C核磁気共鳴 ((13) C NMR) スペクトロスコピーは, (13) Cの組み込みパターンを決定します.
主要な成果:
- 酵母からのピリドキサミン二酸化塩化物の (13) C 組み込みパターンは,E. coli のピリドキシンと有意に異なっていた.
- イーストでは,ピリドキサミンのC ((5) 鎖は,シチジンのリボース成分に似た (13) C分布を示した.
- これは,酵母におけるピリドキサミンとリボースの合成のための一般的なグルコース由来ペントゥロースまたはペントース中間物質を示唆しています.
結論:
- イーストのビタミンB6の炭素骨格の生合成経路は,E. coliのそれとは大きく異なる.
- イーストは,ピリドキサミンとリボースの両方の合成のために,おそらくグルコースから派生した一般的なペントーゼ/ペンチュロゼ中間物質を使用します.
- この発見は,微生物のビタミンB6バイオシンセシスに関する新しい洞察と,代謝工学の潜在的なターゲットを提供します.
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