外向きに開かれた形状のフコゼトランスポーターの構造
Shangyu Dang1, Linfeng Sun, Yongjian Huang
1State Key Laboratory of Bio-membrane and Membrane Biotechnology, Center for Structural Biology, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China.
Nature
|September 30, 2010
まとめ
研究者は,Escherichia coliからFucPトランスポーターの結晶構造を決定し,その外側に開いた形状を明らかにしました. これは,メジャーファシリテータースーパーファミリー (MFS) トランスポーターのメカニズムとl-フコザの吸収に関する重要な洞察を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 微生物学 微生物学とは
背景:
- メジャーファシリテーター・スーパーファミリー (MFS) のトランスポーターは,古くから広く存在している二次活性トランスポーターです.
- Escherichia coliでは,FucPは,l-フコゼの吸収を担当するMFSプロトンシンポーターである.
- MFSトランスポーターの原子構造は限られており,外向きに開かれた形状は特徴づけられていない.
研究 の 目的:
- FucPトランスポーターの結晶構造を決定する.
- MFSトランスポーターの外向き開いた形状を明らかにする.
- FucPの輸送メカニズム,エネルギーカップリング,および基板認識に関する洞察を得るために.
主な方法:
- 3.1 Åの解像度のX線結晶学.
- インビヴォとインビトロ生化学実験.
- 構造ベースの生化学分析.
主要な成果:
- 外側に開いた形状のFucPの結晶構造が決定されました.
- FucPは,そのNとCドメインで対照的な静電面と排水面を持つアンフィパシー腔を示しています.
- 2つの酸性残留物,Asp46とGlu135は,陽子化/脱陽子化サイクルを経て,活性輸送に不可欠である.
結論:
- 決定された構造は,外向きに開いた状態のMFSトランスポーターの最初の視点を提供します.
- 対照的なドメイン表面と重要な酸性残留物は,FucPの輸送機構にとって非常に重要です.
- この研究は,MFSトランスポーター機能とエネルギーカップリングに関する構造的および生化学的な洞察を提供します.
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