在Arabidopsis thaliana的长时间氧气和超氧化物局部化Cryptochrome
K Michael Salerno1, Janna Domenico1, Nam Q Le1
1Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, Maryland 20723, United States.
Journal of chemical information and modeling
|October 24, 2023
概括
加密染色体结合氧气,可能形成超氧化物. 分子动力学模拟显示,氧和超氧可以长时间结合加密色蛋白质,这表明它在生物氧化还原反应中起作用.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 计算生物学 计算生物学
背景情况:
- 加密染色体是保存的蛋白质,在它们的光聚酶同质区 (PHR) 中结合黄氨酸二核酸 (FAD).
- FAD的氧化还原状态和光吸收对于加密色的功能至关重要.
- 像超氧化物一样,反应性氧物种 (ROS) 具有生物学意义,但它们在加密染色体中的形成尚不清楚.
研究的目的:
- 为了研究氧气与*Arabidopsis thaliana*加密染色1 (AtCRY1) PHR域的相互作用.
- 为了确定加密色素是否可以通过FAD的电子转移促进超氧化物的形成.
主要方法:
- 氧气与AtCRY1 PHR域相互作用的分子动力学 (MD) 模拟.
- 使用MD轨迹和复制模拟来分析氧气结合位置和解结合时间.
- 使用马库斯理论对已识别的结合点进行电子转移速率的估计.
主要成果:
- 观察到氧气分子在AtCRY1 PHR域内局部化几十纳秒.
- 超氧化物分子在蛋白质内的局部化时间明显较长.
- 鉴定到的结合点表明,FAD向氧气的电子转移有可能发生.
结论:
- 在加密染色体内,氧和超氧的长时间结合支持它们在氧化还原反应中的潜在作用.
- 这些发现表明,超氧化物形成的可能机制是由加密色素催化.
- 与电子转移黄蛋白 (ETF) 的比较突出了保存的FAD结合蛋白机制.
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