Rubisco Catalytic Properties and Temperature Response in Crops
Rubisco Catalytic Properties and Temperature Response in Crops
复制标题
DOI：
10.1104/pp.16.01846
复制
发表时间：
2016-08-01
期刊：
影响因子：
7.4
通讯作者：
Galmes, Jeroni
中科院分区：
文献类型：
--
作者：
Hermida-Carrera, Carmen;Kapralov, Maxim V.;Galmes, Jeroni
Rubisco催化特性及其热依赖性是限制植物CO2同化潜力的两个主要因素。在这项研究中，我们提出了20种作物在三个不同的温度下的Rubisco动力学的配置文件。结果在很大程度上证实了存在显着的物种之间的Rubisco动力学变化。虽然有些物种倾向于目前Rubisco具有较高的热敏感性（如水稻）比其他（如莴苣），种间差异取决于动力学参数。比较不同动力学参数的温度响应，Rubisco K-m的CO2呈现较高的活化能比最大羧化速率和CO2补偿点在线粒体呼吸的情况下。Rubisco大亚基序列分析揭示了具有特定动力学特征的枝条中存在适应性进化位点。由于Rubisco动力学和它们的温度依赖性是物种特异性的，它们在很大程度上影响了来自不同作物的Rubisco的同化潜力，特别是在那些诱导Rubisco限制的光合作用的条件下（即在羧化位点处的低CO2可用性和高温）。作为一个例子，在25摄氏度，Rubisco从大麦和大豆，分别提出，在高和低叶绿体CO2浓度的CO2同化的最高和最低的潜力。在我们看来，这些信息是相关的，以改善光合作用模型，并应考虑在未来的尝试，设计更有效的Rubiscos。
Rubisco catalytic traits and their thermal dependence are two major factors limiting the CO2 assimilation potential of plants. In this study, we present the profile of Rubisco kinetics for 20 crop species at three different temperatures. The results largely confirmed the existence of significant variation in the Rubisco kinetics among species. Although some of the species tended to present Rubisco with higher thermal sensitivity (e.g. Oryza sativa) than others (e.g. Lactuca sativa), interspecific differences depended on the kinetic parameter. Comparing the temperature response of the different kinetic parameters, the Rubisco K-m for CO2 presented higher energy of activation than the maximum carboxylation rate and the CO2 compensation point in the absence of mitochondrial respiration. The analysis of the Rubisco large subunit sequence revealed the existence of some sites under adaptive evolution in branches with specific kinetic traits. Because Rubisco kinetics and their temperature dependency were species specific, they largely affected the assimilation potential of Rubisco from the different crops, especially under those conditions (i.e. low CO2 availability at the site of carboxylation and high temperature) inducing Rubisco-limited photosynthesis. As an example, at 25 degrees C, Rubisco from Hordeum vulgare and Glycine max presented, respectively, the highest and lowest potential for CO2 assimilation at both high and low chloroplastic CO2 concentrations. In our opinion, this information is relevant to improve photosynthesis models and should be considered in future attempts to design more efficient Rubiscos.