そのSARドメインの膜放出後のディスルファイドイソメリゼーションは,P1ライソ酵素を活性化させます
Min Xu1, Arockiasamy Arulandu, Douglas K Struck
1Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, USA.
Science (New York, N.Y.)
|January 8, 2005
まとめ
Escherichia coli の P1 リゾ酵素 (Lyz) は,P1 ホリンによって放出されるまで,細胞膜で不活性に保たれています. 放出されると,Lyzは構造変化を遂げ,活性化のために二硫化物結合の再編成をします.
科学分野:
- バクテリオファージの生物学
- 分子微生物学 分子微生物学
- タンパク質の構造と機能
背景:
- P1ライゾ酵素 (Lyz) は,Escherichia coliの周回血質に分泌されるエンドリシンです.
- Lyzは,バクテリオファージP1複製の前に,不活性で膜に結合した形で蓄積されます.
- この不活性状態は,溶解とファグの放出を制御するために極めて重要です.
研究 の 目的:
- P1ライソ酵素 (Lyz) の活性化を制御するメカニズムを解明する.
- Lyz活性化に関連した構造的および生化学的変化を調査する.
- Lyz 調節における信号停止放出 (SAR) ドメインの役割を理解する.
主な方法:
- P1 Lyz.の遺伝子と生化学分析.
- 不活性および活性なLyz形態の結晶構造の決定.
- SARドメインにおけるチオルジスルファイドイソメリゼーションの特徴.
主要な成果:
- P1 Lyzは,トポロジカル,コンフォメーション,およびコヴァレンント制御を通じて不活性状態に維持されます.
- P1ホリンによる膜からの放出は,Lyzの活性化を誘発する.
- 活性化には,N端のSARドメインシステインに依存する分子内チオル硫化物イソメリゼーションが含まれます.
結論:
- P1 Lyzの活性化は,膜結合とP1ホリンによって調節される多段階のプロセスです.
- Lyzにおける構造的および二硫化結合の再編成は,その触媒活性に不可欠である.
- SARドメインはP1endolysinの調節された活性化において重要な役割を果たします.
さらに関連する動画
09:37Combining Non-reducing SDS-PAGE Analysis and Chemical Crosslinking to Detect Multimeric Complexes Stabilized by Disulfide Linkages in Mammalian Cells in Culture
Published on: May 2, 2019
08:37Purification of the Sarco-Endoplasmic Reticulum Ca2+-ATPase from Rabbit Muscle
Published on: March 21, 2025
関連する概念動画
01:26Protein Modifications in the RER
Modification of secretory and transmembrane proteins entering the rough ER begins in the ER lumen. These modifications aid in protein folding and stabilize the acquired tertiary structure. Protein modifications in the rough ER co-occur at different stages of protein folding.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
01:34ATP Driven Pumps II: P-type Pumps
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...
01:12GPCR Desensitization
G protein-coupled receptor (GPCR) signaling plays a crucial role in cell functioning. GPCR desensitization is an equally essential process. It allows cells to respond to changing environments and regain sensitivity to new stimuli while preventing unnecessary stimulation when no longer needed. Prolonged exposure to stimuli leads to GPCR desensitization. It involves blocking the receptors from binding and activating additional G proteins. This inhibits activation of downstream effectors, thereby...