ビタミンB6反応性および反応性のないシスタチオニニウリア:二つの変異分子形態
Science (New York, N.Y.)
|December 19, 1975
まとめ
ビタミンB6に反応するシスタチオニヌーリアは,ピリドクサールリン酸でシスタチオナーゼの活性が増加したことを示した. この酵素は,免疫化学的に正常なシスタチオネーゼと同一であり,B6に反応しない症例とは違いました.
科学分野:
- バイオケミストリー バイオケミストリー
- 遺伝学 遺伝学とは
- メタボリック障害 メタボリック障害
背景:
- シスタチオニニウリアは,まれな代謝障害である.
- ビタミンB6は,アミノ酸代謝に関与する酵素の重要なコファクターです.
- シスタチオニニウリアにおける特定の酵素欠陥は,必ずしも明確ではない.
研究 の 目的:
- ビタミンB6反応性および反応性のないシスタチオニニウリアにおけるシスタチオナースの活性および免疫化学的性質を調査する.
- ピリドクサルリン酸が,影響を受けた細胞系における酵素機能を回復できるかどうかを判断する.
主な方法:
- リンパ性細胞系抽出物に関する酵素活性測定法.
- ピリドクサールリン酸サプリメント in vitro.
- ヒト肝臓シスタチオナゼに対する抗血清を用いた免疫拡散アッセイ.
主要な成果:
- ビタミンB6に反応した患者からの細胞抽出物におけるピリドクサールリン酸によってシスタチオナーゼの活性が有意に増加した.
- 反応した患者からのシスタチオネーゼタンパク質は,免疫化学的に正常なシスタチオネーゼと同一であった.
- ビタミンB6に反応しない患者の細胞抽出物では,活性や免疫化学的同一性の増加は観察されなかった.
結論:
- ビタミンB6に反応するシスタチオニニウリアの形態は,ピリドクサールリン酸の結合または酵素構成に影響を与える変異を含む可能性があります.
- サイスタチオネーゼは,このビタミンB6に反応する患者で欠乏している可能性が高い酵素です.
- B6に反応しない患者は,別の酵素欠陥またはより深刻な変異を持つ可能性があります.
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