陆地植物中的生物物理碳缩机制:来自反应-扩散建模的见解
Joshua A M Kaste1,2, Berkley J Walker2,3, Yair Shachar-Hill2
1Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Rd, East Lansing, MI 48823.
bioRxiv : the preprint server for biology
|January 23, 2024
概括
碳缩机制 (CCM) 在鲁比斯科周围增加了二氧化碳,但它们在C3工厂的效率取决于二氧化碳膜透性. 生物物理CCM可能会增加二氧化碳的固定,但能源成本更高.
科学领域:
- 植物生物学 植物生物学
- 生物化学 生物化学
- 光合作用研究研究 光合作用研究
背景情况:
- 碳度机制 (CCM) 通过在鲁比斯科周围提升CO2来增强CO2的固定,从而减少光透气.
- 生物物理CCM在水生微生物中普遍存在,但在陆地植物中很少见,只出现在角虫中.
- 了解C3植物的CCM效率对于改善作物光合作用至关重要.
研究的目的:
- 使用反应-扩散模型预测C3植物中生物物理CCM的效率.
- 了解在陆地植物光合作用中实施CCM的能源成本和好处.
主要方法:
- 采用了空间分辨的反应扩散建模.
- 预测了Rubisco和和光效的使用效率.
- 评估了二氧化碳膜透性对CCM效率的影响.
主要成果:
- CCM的能源效率对二氧化碳膜透性敏感,文献值导致光使用效率低于以前建模的.
- 在C3工厂中实施基于体的CCM可能会增加二氧化碳的固定,但会产生更高的能源成本.
- 在模仿生化CCM的条件下或当气体交换受到限制时,CCM是有益的,如在角草中所见.
结论:
- 在特定条件下,生物物理CCM可以增强C3工厂的CO2净固定,例如低体CO2或气体交换限制.
- 生物物理CCM的高能耗成本解释了它们在陆地植物中的稀有性,与没有CCM的C3植物相比.
- 这项研究提供了关于角虫中CCM的独特进化和pyrenoids的多重进化发生的见解.
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