细菌PASTA激酶的激活环中的形态变化
Matthew S Bluma1, Kathryn M Schultz2, Christopher J Kristich1
1Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
Protein science : a publication of the Protein Society
|June 14, 2023
概括
酸化通过改变激活循环动态来控制细菌PASTA激酶IreK. 这种循环运动对于IreK与其基质IreB相互作用至关重要,影响细菌过程.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- 帕斯塔激酶是对细菌病原体毒性至关重要的跨膜蛋白质.
- 这些激酶具有独特的域结构:细胞外PASTA,跨膜螺旋和细胞内Ser/Thr激酶.
- 已知激活循环的酸化调节激酶活性,但机制尚不清楚.
研究的目的:
- 为了研究IreK激活循环在酸化后的动态变化.
- 阐明酸化调节IreK激酶活性和基质相互作用的机制.
- 了解激活循环动态在IreK-IreB交互中的作用.
主要方法:
- 在IreK激活循环上使用Site-directed spin labeling (SDSL) 来标记特定的网站.
- 连续波 (CW) 电子磁共振 (EPR) 谱学被用来分析标记激活循环的动态.
- 评估了酸化和与基质IreB相互作用对循环动态的影响.
主要成果:
- IreK激活循环存在于一个更为刚性,不动的状态,当dephosphorylated.
- 自酸化会诱导形状变化,使激活循环转移到一个更具流动性的状态.
- 这种增加的循环流动性对于IreK及其基质IreB之间的后续相互作用至关重要.
结论:
- IreK激活循环的酸化依赖的动态对于其功能至关重要.
- 该研究揭示了一种机制,通过酸化调节的循环流动性控制了基质结合和下游信号传输.
- 这些发现为细菌PASTA激酶的调节及其在病变发生中的作用提供了洞察力.
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