前腸発酵体の胃リゾジームにおける適応的進化
C B Stewart1, J W Schilling, A C Wilson
1Department of Biochemistry, University of California, Berkeley 94720.
Nature
|November 2, 1987
まとめ
哺乳類の収束進化は,牛とラングルの胃リゾーザムを引き起こした. ラングルのリゾ酵素は急速に進化し,ダーウィンの選択が消化のための適応を促したことを示唆しています.
科学分野:
- 進化生物学の進化生物学について
- バイオケミストリー バイオケミストリー
- 哺乳類の消化器系について
背景:
- 哺乳類における発酵前皮の収束進化.
- リゾーイジムを胃細菌解消酵素として反動物 (例えば,牛) とコロビン類猿 (例えば,ラングル) で採用する.
- 胃リソ酵素の共有された物理化学的および触媒的性質は,胃環境への適応を示唆する.
研究 の 目的:
- 胃リゾジームの共有特性の分子基盤を調査する.
- ラングルの胃リソ酵素の進化軌跡と選択圧力を決定する.
主な方法:
- ラングルの胃リソ酵素の配列化.
- 系統樹の分析で,ラングルリゾジームを他の既知のリゾジームと比較した.
- 配列と機能特性の比較分析. 配列と機能特性の比較分析.
主要な成果:
- ラングルのリゾジーム配列は,牛の胃リゾジームと類似している.
- ラングルのリゾージムは,他の霊長類のリゾージムよりも約2倍速く進化した.
- 証拠は,ランガーと牛の胃のリゾジメの間の機能的および配列の収束を示唆しています.
結論:
- 肯定的なダーウィンの選択は,ラングルの胃リソ酵素の重要な進化を促した可能性がある.
- 胃リソ酵素の収束進化は,食生活の変化に対応した適応性タンパク質の進化を強調しています.
- この研究は,消化酵素の適応の基礎となる分子機構の洞察を提供します.
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