在其SAR域的膜释放后,二硫化物异构化激活了P1溶酶
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
概括
大肠杆菌中的P1溶酶 (Lyz) 在细胞膜中保持不活跃,直到被P1holin释放. 在释放后,Lyz经历了结构变化和二硫化物键重组以激活.
科学领域:
- 细菌生物学的生物学
- 分子微生物学分子微生物学
- 蛋白质的结构和功能.
背景情况:
- P1溶酶 (Lyz) 是一种内溶酶,分泌到大肠杆菌的周围质中.
- 在菌体P1复制之前,lys 积聚在一个不活跃的,与膜结合的形式.
- 这种不活性状态对于控制溶解和菌体释放至关重要.
研究的目的:
- 阐明控制P1溶酶 (Lyz) 激活的机制.
- 研究与Lyz激活相关的结构和生化变化.
- 了解信号停止释放 (SAR) 域在lys调节中的作用.
主要方法:
- 对P1 Lyz.的遗传和生化分析.
- 确定非活性和活性Lyz形式的晶体结构.
- 在SAR域中对硫化-二硫化物异构的表征.
主要成果:
- 通过拓学,构造学和共价性控制,P1 Lyz 保持在非活性状态.
- 通过P1holin从膜中释放会触发Lyz激活.
- 激活涉及依赖于N端SAR域cysteine的分子内硫酸二醇异构.
结论:
- P1 Lyz激活是一个多步骤的过程,由膜结合和P1 holin.调节.
- 在Lyz中,结构和二硫化物键的重新排列对于其催化活性至关重要.
- SAR域在调节P1内分泌酶的激活中起着至关重要的作用.
更多相关视频
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
相关概念视频
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...