在中性氨基酸紫外线光解中观察到显著的基质不对称
Brendan Moore1, Linshan Zeng1, Pavle Djuricanin1
1Department of Chemistry, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada.
Journal of the American Chemical Society
|November 7, 2024
概括
循环偏振的光子可以在氨基酸解离率上产生显著的不对称性. 这一发现支持了外星因素可能推动生命的同质性起源的假设.
科学领域:
- 天体生物学
- 化学物理
- 生命的起源
背景情况:
- 生物系统中同质性 (一种反体的占主导地位) 的起源是一个根本的未解决的问题.
- 外星人的假设表明,在太空中循环极化光可以诱导同质性,但由于感知到低光学旋转分散,这一点受到争议.
- 之前的研究表明分子光解离中的有限不对称性,阻碍了对地球外起源的接受.
研究的目的:
- 调查循环极化光子在氨基酸解离中诱导显著的奇拉不对称性的潜力.
- 通过实验确定特定的氨基酸对应物是否表现出光解离率的显著不对称性.
- 评估非对称光解离的可行性作为确定生物同质性的机制.
主要方法:
- 使用循环极化光子测量中性氨基酸对应物的奇拉破坏性解离率.
- 测量异构度因子,测量光解离异称性.
- 对不同氨基酸状态和条件的观察到的异性质因子与先前报告的值进行比较.
主要成果:
- 当暴露于循环极化光子时,中性氨基酸的特定适配体在解离率上表现出显著的不对称性.
- 最低能量的氨酸呈现出0.1的显著高异性因子.
- 这种观察到的异构性大大大大大于zwitterionicleucine或气相leucine组合所报告的值.
结论:
- 特定氨基酸对应物的不对称光解会产生大量的反体过量.
- 一个显著的异构性因子,即使看起来很小,也会导致相当大的体失衡.
- 这为不对称的光解离提供了强有力的实验支持,作为生物同质性起源的可信机制.
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