Roussel Marc R, Igamberdiev Abir U
Department of Chemistry and Biochemistry, University of Lethbridge, University Hall, Lethbridge, Canada.
Biosystems. 2011 Feb;103(2):230-8. doi: 10.1016/j.biosystems.2010.07.020. Epub 2010 Aug 23.
We classify mathematical models that can be used to describe photosynthetic oscillations using ideas from nonlinear dynamics, and discuss potential mechanisms for photosynthetic oscillations in the context of this classification. We then turn our attention to recent experiments with leaves transferred to a low CO₂ atmosphere which revealed stochastic oscillations with a period of a few seconds. Rubisco is the enzyme that takes both CO₂ and O₂ as substrates correspondingly for photosynthetic assimilation and for photorespiration. Photosynthesis depletes CO₂ and produces O₂ while respiration and photorespiration work in the opposite direction, so the product of one process becomes the reactant of the other coupled process. We examine the possibility of oscillations of CO₂ and O₂ in the leaf in relation to photorespiration. We suggest that in the cell, oscillations with a period of a few seconds, corresponding to the time between photosynthetic CO₂ fixation and photorespiratory CO₂ release, underlie the dynamics of metabolism in C₃ plants.
我们运用非线性动力学的概念对可用于描述光合振荡的数学模型进行分类，并在此分类框架下讨论光合振荡的潜在机制。接着，我们将注意力转向近期对转移至低二氧化碳大气环境中的叶片进行的实验，这些实验揭示了周期为几秒的随机振荡。核酮糖-1,5-二磷酸羧化酶/加氧酶（Rubisco）是一种酶，它分别以二氧化碳和氧气作为底物，用于光合同化作用和光呼吸作用。光合作用消耗二氧化碳并产生氧气，而呼吸作用和光呼吸作用则方向相反，因此一个过程的产物成为另一个耦合过程的反应物。我们研究了叶片中二氧化碳和氧气振荡与光呼吸作用相关的可能性。我们认为，在细胞中，周期为几秒的振荡，对应于光合固定二氧化碳和光呼吸释放二氧化碳之间的时间，是C₃植物新陈代谢动态变化的基础。
