Increased activity of core photorespiratory enzymes and CO2 transfer conductances are associated with higher and more optimal photosynthetic rates under elevated temperatures in the extremophile Rhazya stricta
Increased activity of core photorespiratory enzymes and CO2 transfer conductances are associated with higher and more optimal photosynthetic rates under elevated temperatures in the extremophile Rhazya stricta
复制标题
核心光呼吸酶活性的增加和二氧化碳转移电导与极端微生物Rhazya stricta在高温下更高和更佳的光合速率相关
DOI：
10.1111/pce.14711
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Walker, Berkley J.
中科院分区：
文献类型：
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作者：
Gregory, Luke M.;Roze, Ludmila V.;Walker, Berkley J.
增加光呼吸和优化内在水分利用效率是高温下光合固碳的独特挑战。为了确定植物如何适应高温下的高光呼吸率，同时保持水分利用效率，我们对C3极端微生物Rhazya stricta进行了深入的气体交换和生化分析。结果表明，R. strictas支持高温下较高的光呼吸速率，这些较高的光呼吸速率与关键光呼吸酶的活性增加有关;磷酸乙醇酸磷酸酶和过氧化氢酶。增加的光呼吸酶活性可以通过减少酶瓶颈和允许在高光呼吸速率下最小的抑制剂积累来增加光呼吸的总体能力。此外，我们发现CO2传输传导（气孔和叶肉）重新分配，以提高水分利用效率在R。严格地说，光合作用对温度的反应并不一定。这些结果表明，重要的适应性战略在R。stricta在高温下保持光合速率，最佳失水。这些策略在R中找到。strictamay可以告知育种和工程努力在其他C3物种，以提高光合效率在高温下。
Increase photorespiration and optimising intrinsic water use efficiency are unique challenges to photosynthetic carbon fixation at elevated temperatures. To determine how plants can adapt to facilitate high rates of photorespiration at elevated temperatures while also maintaining water‐use efficiency, we performed in‐depth gas exchange and biochemical assays of the C3extremophile,Rhazya stricta. These results demonstrate thatR. strictasupports higher rates of photorespiration under elevated temperatures and that these higher rates of photorespiration correlate with increased activity of key photorespiratory enzymes; phosphoglycolate phosphatase and catalase. The increased photorespiratory enzyme activities may increase the overall capacity of photorespiration by reducing enzymatic bottlenecks and allowing minimal inhibitor accumulation under high photorespiratory rates. Additionally, we found the CO2transfer conductances (stomatal and mesophyll) are re‐allocated to increase the water‐use efficiency inR. strictabut not necessarily the photosynthetic response to temperature. These results suggest important adaptive strategies inR. strictathat maintain photosynthetic rates under elevated temperatures with optimal water loss. The strategies found inR. strictamay inform breeding and engineering efforts in other C3species to improve photosynthetic efficiency at high temperatures.