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鲁比斯科的进化动态:小子单位的出现及其在时间上的影响

Kaustubh Amritkar^1,2, Bruno Cuevas-Zuviría^1,3, Betül Kaçar¹

¹Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA.

Molecular biology and evolution

|January 8, 2025

概括

利布洛斯-1,5-双酸碳糖酶/氧化酶 (RuBisCO) 的小子单元通过限制灵活性,影响了其早期的进化. 这种古老的酶.

科学领域:

生物化学和分子生物学
进化生物学进化生物学
生物地质化学生物地质化学

背景情况:

利布-1,5-双酸碳氧化酶/氧化酶 (RuBisCO) 对二氧化碳固定和全球生物地质化学至关重要.
形式I的RuBisCO复合体由大子单元和独特的小子单元组成,形成一个六边形结构.
小子单元的整合被假设是对大气O2水平上升的关键适应,大约25亿年前.

研究的目的:

调查小子单元早期整合对Form-I RuBisCO分子动态的影响.
探索RuBisCO的进化轨迹,以应对古老的环境变化.
评估小子单元在 CO2/O2 气体分布中在进化时间内的保留作用.

主要方法:

对现存和祖先的RuBisCO序列和结构进行全面的进化分析.
古代RuBisCO复合体的分子动力学模拟.
在模拟的古老RuBisCO结构周围对CO2和O2气体分布的分析.

主要成果:

在RuBisCO的早期历史中,小型子单位的整合限制了大型子单位的结构灵活性.
这种限制显著影响了Form-I RuBisCO复合体的进化路径.
有证据表明,小子单元的拟议的"二氧化碳储存库"作用并非在进化过程中得到保存.

结论:

小子单元的集成是塑造RuBisCO进化和分子动态的关键事件.
鲁比斯科的进化和生物物理反应表明,在地质时间尺度上对环境变化有多层次的适应.
了解RuBisCO进化提供了对酶适应变化的行星条件的见解.

关键词:

卢比斯科 (RuBisCO) 是一种石头.祖先的序列重建的重建.小小的子单位.结构动力学结构动力学

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