多样性驱动的生物化学调查揭示了鲁比斯科的二维结构起源
bioRxiv : the preprint server for biology
|November 24, 2025
概括
研究人员探索了Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) 的多样化世界,发现深层分支的形式组装成二元体,这表明其起源很古老. 他们还发现了一种新的,大型的鲁比斯科,具有独特的结构折叠.
科学领域:
- 生物化学和分子生物学
- 微生物生态学 微生物生态学
- 进化生物学 进化生物学
背景情况:
- 鲁比斯科 (ribulose-1,5-bisphosphate carboxylase/oxygenase) 是碳固定的一个关键酶,存在于所有生命领域.
- 生物化学研究在历史上一直专注于有限的Rubisco类型,尽管转基因组学的进步揭示了巨大的微生物多样性.
- 序列数据的快速增长超过了生物化学表征,在理解Rubisco的功能和结构多样性方面留下了重大差距.
研究的目的:
- 系统地调查Rubisco酶超级家族的功能和结构多样性.
- 为了表征以前代表性不足和深度分支的鲁比斯科群.
- 为修订的鲁比斯科命名体系整合遗传学和生物化学数据.
主要方法:
- 系统地采样和合成各种Rubisco序列库,强调研究不足的类型.
- 更新了家族遗传学分析,以重建鲁比斯科超级家族内的进化关系.
- 新型鲁比斯科酶的生物化学和结构特征,包括迄今为止发现的最大的一个.
主要成果:
- 遗传学分析表明,许多深度分支的鲁比斯科形成二元体,支持酶超级家族的二元起源.
- 发现和结构性表征迄今为止描述的最大的鲁比斯科酶,来自一个神秘的,早期分支的子类.
- 在这个大型Rubisco中发现了新的结构折叠,在超级家族中以前没有观察到.
结论:
- 鲁比斯科超级家族很可能起源于二度形状,与当前占主导地位的六度形状I形状形成对比.
- 新型结构和大型酶的发现扩大了已知的Rubisco的多样性.
- 建议修订命名法,以更好地反映当前的进化和结构见解,并适应未来的发现.
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