エシェリキア大腸菌からのグリセロール-3-リン酸媒体の構造とメカニズム
Yafei Huang1, M Joanne Lemieux, Jinmei Song
1Skirball Institute of Biomolecular Medicine and Department of Cell Biology, New York University School of Medicine, 540 First Avenue, New York, NY 10016, USA.
まとめ
グリセロール-3フォスファートトランスポーターであるGlpTの構造は,偽の二重対称性と,基板結合部位を形成するアルギニンを含む中央の孔を明らかにします. このトランスポーターは,代替アクセスメカニズムで機能している可能性が高い.
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
- メンブレーン輸送 メンブレーン輸送
背景:
- メジャーファシリテータースーパーファミリーは,二次膜トランスポーターの最大のグループです.
- トランスポーターメカニズムを理解することは,細胞の機能にとって極めて重要です.
研究 の 目的:
- グリセロール-3フォスファートトランスポーターであるGlpTの高解像度構造を決定する.
- 基板が膜を横断して転位するメカニズムを解明する.
主な方法:
- X線結晶学を用いて,GlpT.の3.3アンストームの解像度構造を取得しました.
- 構造分析は,基板結合部位と形状の変化を特定することに焦点を当てました.
主要な成果:
- GlpT構造は,そのアミノとカルボキシル末端の半分の間に擬似二重対称性を示しています.
- 周辺プラズマに閉ざされた中央の毛穴には,2つのアルギニンが含まれており,基板結合部位として特定されています.
- サブストラット結合により,よりコンパクトなタンパク質構成が誘発されます.
結論:
- GlpTは,単一の結合サイト,交代アクセスメカニズムを介して動作する可能性があります.
- GlpTの輸送機能のために,ローカー・スイッチ型の動きが提案されています.
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