F1-ATPaseは,高度に効率的な分子モーターで,離散的な120度ステップで回転します
1Department of Physics, Faculty of Science and Technology, Keio University, Yokohama, Japan.
Cell
|July 10, 1998
まとめ
F1-ATPase酵素は回転モーターとして作用し,中央のガンマサブユニットは段階的に回転する. このモーター,このモーター.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- バイオフィジックス 生物物理学
背景:
- ATP合成酵素は,細胞のエネルギー生産に責任を負う重要な酵素複合体です.
- F1-ATPaseはATP合成酵素の触媒核であり,分子回転モーターとして機能する.
研究 の 目的:
- 単一のF1-ATPase分子の機械的性質とエネルギー伝導を調査する.
- F1-ATPase回転モーターのステップメカニズムと作業出力を理解するために.
主な方法:
- F1-ATPase酵素を観察し,操作するために単一分子生物物理学の技術が採用されました.
- 異なる負荷条件下での回転ステップと作業出力の測定が行われました.
主要な成果:
- F1-ATPaseのガンマサブユニットは,ATPの水解によって駆動され,離散的な120度ステップで回転します.
- 酵素は時折,後退的なステップ行動を示します.
- 各ステップで実行される作業は,適用される負荷の広い範囲で一定であり,ATP水解の自由エネルギーに近似します.
結論:
- F1-ATPaseは効率的な回転モーターとして機能し,ATPからの化学エネルギーを機械的な作業に変換します.
- ステップごとに一貫した作業出力は,酵素の堅固なエネルギー変換機構を強調しています.
関連する概念動画
ATP Driven Pumps I: An Overview
8.1K
ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
8.1K
ATP Synthase: Mechanism
16.0K
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased...
16.0K
ATP Synthase: Structure
16.3K
ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
16.3K
The Movement of Organelles and Vesicles
5.4K
In eukaryotic cells, cytoskeletal filaments such as actin, microtubules, and intermediate filaments form a mesh-like cytoskeletal network. These filaments serve as tracks for transporting cellular cargo. Specialized motor proteins use the chemical energy stored in adenosine triphosphate (ATP) for this transport. During interphase, microtubules are polarized, with the plus-end towards the cell periphery and the minus-end towards the cell center. Two microtubule-associated motor proteins,...
5.4K
ATP Driven Pumps II: P-type Pumps
5.2K
The P-type pumps are a large family of integral membrane transporter ATPases. They are divided into five major types based on substrate specificity, from I to V.
A typical P-type pump has three cytosolic domains: nucleotide-binding (N), phosphorylation (P), and activator (A) domains. These domains are connected to the membrane-spanning helices by short amino acid segments. ATP hydrolysis and covalent phosphoenzyme intermediate formation are crucial parts of the catalytic cycle. At the highly...
A typical P-type pump has three cytosolic domains: nucleotide-binding (N), phosphorylation (P), and activator (A) domains. These domains are connected to the membrane-spanning helices by short amino acid segments. ATP hydrolysis and covalent phosphoenzyme intermediate formation are crucial parts of the catalytic cycle. At the highly...
5.2K
Chemiosmosis and ATP Synthesis
3.7K
The electron transport chain is a critical component of cellular respiration, occurring in the inner mitochondrial membrane. It facilitates the transfer of high-energy electrons from reduced cofactors NADH and FADH₂ to molecular oxygen, the final electron acceptor. This transfer of electrons through a series of protein complexes is tightly coupled to the translocation of protons across the membrane, generating a proton gradient essential for ATP synthesis.Electron Flow and Proton...
3.7K


