本文为2017年12月11日Nature Plants文章，

植物通过光呼吸途径同化氮，进而增加二氧化碳的吸收

原题目为：

Plants increase CO2 uptake by assimilating nitrogen via the photorespiratory pathway

光呼吸通常被认为是一个浪费的过程，因此它是增加作物产量的主要生物工程目标。光呼吸代谢被整合到叶片代谢中，因此可能有一定的益处。这里，我们结果显示植物可以通过光呼吸途径，固定碳成为除碳水化合物以外的氨基酸，从而从头同化氮，进而可以增加光合CO2 摄取率。在低光呼吸条件下，NO₃^- 处理的植物在光呼吸作用下的CO2同化速率较高，而缺乏NO3- 营养的植物表现出较低的CO2 摄取。我们修改了广泛使用的Farquhar，von Caemmerer和Berry光合作用模型，以包括光呼吸途径中对氮同化的碳和电子的要求。我们改进的模型改善了光合CO2 吸收和光合电子传递速率的预测。结果突出了：在降低Rubisco羧化效率的情况下，光呼吸如何可以提高光合性能。

Photorespiration is a major bioengineering target for increasing crop yields as it is often considered a wasteful process. Photorespiratory metabolism is integrated into leaf metabolism and thus may have certain benefits. Here, we show that plants can increase their rate of photosynthetic CO2uptake when assimilating nitrogen de novo via the photorespiratory pathway by fixing carbon as amino acids in addition to carbohydrates. Plants fed NO₃⁻  had higher rates of CO2 assimilation under photorespiratory than low-photorespiratory conditions, while plants lacking NO₃⁻ nutrition exhibited lower stimulation of CO2 uptake. We modified the widely used Farquhar, von Caemmerer and Berry photosynthesis model to include the carbon and electron requirements for nitrogen assimilation via the photorespiratory pathway. Our modified model improves predictions of photosynthetic CO2 uptake and of rates of photosynthetic electron transport. The results highlight how photorespiration can improve photosynthetic performance despite reducing the efficiency of Rubisco carboxylation.

每日一词

photorespiration

英[fəʊtəʊrespɪ'reɪʃən]

美[ˌfoʊtoʊˌrespə'reɪʃən]

n. 光呼吸（作用）;

[例句]The curve pattern showed that the ratio of dark-respiration to photorespiration increased at first and decreased later on.

暗呼吸及光呼吸速率与叶水势降低的关系，呈现先升高而后下降的曲线类型。