ジャーナル: Cell / 年: 2001 タイトル: ATP-bound states of GroEL captured by cryo-electron microscopy. 著者: N A Ranson / G W Farr / A M Roseman / B Gowen / W A Fenton / A L Horwich / H R Saibil / 要旨: The chaperonin GroEL drives its protein-folding cycle by cooperatively binding ATP to one of its two rings, priming that ring to become folding-active upon GroES binding, while simultaneously ...The chaperonin GroEL drives its protein-folding cycle by cooperatively binding ATP to one of its two rings, priming that ring to become folding-active upon GroES binding, while simultaneously discharging the previous folding chamber from the opposite ring. The GroEL-ATP structure, determined by cryo-EM and atomic structure fitting, shows that the intermediate domains rotate downward, switching their intersubunit salt bridge contacts from substrate binding to ATP binding domains. These observations, together with the effects of ATP binding to a GroEL-GroES-ADP complex, suggest structural models for the ATP-induced reduction in affinity for polypeptide and for cooperativity. The model for cooperativity, based on switching of intersubunit salt bridge interactions around the GroEL ring, may provide general insight into cooperativity in other ring complexes and molecular machines.
名称: GroEL-ATP from E.coli / タイプ: sample / ID: 1000 / 集合状態: 14-mer / Number unique components: 1
分子量
実験値: 800 KDa / 理論値: 800 KDa
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分子 #1: GroEL
分子
名称: GroEL / タイプ: protein_or_peptide / ID: 1 / Name.synonym: Chaperonin 詳細: D398A mutant; The Asp398Ala mutant of GroEL has severely reduced ATPase activity but can support a round of protein folding. コピー数: 14 / 集合状態: 14-mer / 組換発現: Yes
由来(天然)
生物種: Escherichia coli (大腸菌) / 細胞: E. coli
分子量
実験値: 800 KDa / 理論値: 800 KDa
組換発現
生物種: Escherichia coli (大腸菌)
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実験情報
-
構造解析
手法
クライオ電子顕微鏡法
解析
単粒子再構成法
試料の集合状態
particle
-
試料調製
濃度
0.8 mg/mL
緩衝液
pH: 7.5 / 詳細: 12.5 mM HEPES, 5 mM KCl, 5 mM MgCl2, 250 microM ATP
グリッド
詳細: holey carbon film
凍結
凍結剤: ETHANE / チャンバー内温度: 100 K / 装置: HOMEMADE PLUNGER / 詳細: Vitrification instrument: self made / 手法: Blot for 1 second before plunging