L−アスパラギナーゼの活性性:グルタミンゼフリーと低尿素酸の共活性性
Zahra Zaeimian1, Khalil-Berdi Fotouhifar1, Mohsen Farzaneh2
1Department of Plant Protection, Faculty of Agriculture, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
PloS one
|February 13, 2026
まとめ
エンドフィティック菌はL-アスパラギナーゼの産生をスクリーニングし,Alternaria brassicae Cは高い活性と最小限の共活性を示した. ミネラル塩アガーとシトラートアガールは,L-アスパラギナーゼ生成に推奨されます.
科学分野:
- 微生物学 微生物学とは
- バイオテクノロジー バイオテクノロジー
- 酵素学 酵素学とは
背景:
- L-アスパラギナーゼは,がん治療における重要な酵素である.
- エンドフィティック真菌は,新しい生物活性化合物の潜在的な源である.
- L-グルタミンゼとウレアゼのような共活性性を調査することは,酵素の純度と有効性にとって重要です.
研究 の 目的:
- エンドフィット菌におけるL-アスパラギナーゼの産生を評価する.
- L-アスパラギナーゼの産生とともに,L-グルタミンゼとウレアゼの共活性性を評価する.
- L-アスパラジンと培養媒体が酵素生成に与える影響を決定する.
主な方法:
- L-アスパラギナーゼの活性に対する62のエンドフィティックキノコ単離物のスクリーニング.
- ネスレライゼーション法を用いたL-アスパラギナーゼの活性量の定量化.
- L-アスパラジンによる酵素誘導性と基質調節の評価.
- 酵素生成に及ぼす影響について,10種類の培養媒体を試験した.
主要な成果:
- 62種のうち49種がL-アスパラギナーゼ活性を示し,Cladosporium perangustum EL1がゾーン指数 (6.58) で最高であった.
- Cladosporium cladosporioides Kr5-2はL-アスパラギナーゼの最大活性 (10.78 U mL-1) を示した.
- Alternaria brassicae CはL-アスパラギナーゼの活性度が高い (7.07 U mL-1) で,L-グルタミンゼの活性度が軽微であり,ウレアゼの活性度が低い (1.97 U mL-1) でした.
- L-アスパラギナーゼの生成は誘導可能であり,基板制御されていることが判明しました.
- ミネラル塩アガーとシトラートアガールは,他の試験媒介と異なり,すべての単離体においてL-アスパラギナーゼの生成をサポートしました.
結論:
- エンドファイト菌,特にAlternaria brassicae Cは,L-アスパラギナーゼ生成の有望な源である.
- ミネラル塩アガーとシトラートアガールは,L-アスパラギナーゼ生産媒体の有効な代替品です.
- この研究は,特定の植物種から隔離されたエンドフィティック菌からL-アスパラギナーゼの生成を報告し,それらの共同活動を調査した最初の研究です.
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