Efficient CO2 fixation by surface Prochlorococcus in the Atlantic Ocean.
Efficient CO2 fixation by surface Prochlorococcus in the Atlantic Ocean.
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DOI：
10.1038/ismej.2014.56
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发表时间：
2014-11
期刊：
影响因子：
--
通讯作者：
Zubkov MV
中科院分区：
文献类型：
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作者：
Hartmann M;Gomez-Pereira P;Grob C;Ostrowski M;Scanlan DJ;Zubkov MV
几乎一半的地球表面被海洋所覆盖，海洋中居住着地球上最丰富的光合生物原绿球藻蓝藻。然而，在贫营养开放的海洋中，它们的细胞在透光层的上半部分的大多数有水平的光合色素几乎检测到的流式细胞仪，这表明低效率的二氧化碳固定与其他浮游植物生活在同一沃茨。为了检验后一种假设，在开放的大西洋（30 ° S至30 ° N）的表面沃茨中直接比较了流式细胞术分选的14 C标记的浮游植物细胞的CO2固定率。原绿球藻的CO2固定率至少比最小的质体原生生物和聚球藻蓝藻的CO2固定率高1.5 - 2.0倍，当归一化到使用细胞红色自体荧光评估的光合色素时。因此，我们的数据表明，在贫营养的海洋表面沃茨，色素最小化允许原绿球藻细胞收获丰富的阳光比其他浮游植物更有效。
Nearly half of the Earth's surface is covered by the ocean populated by the most abundant photosynthetic organisms on the planet—Prochlorococcus cyanobacteria. However, in the oligotrophic open ocean, the majority of their cells in the top half of the photic layer have levels of photosynthetic pigmentation barely detectable by flow cytometry, suggesting low efficiency of CO2 fixation compared with other phytoplankton living in the same waters. To test the latter assumption, CO2 fixation rates of flow cytometrically sorted 14C-labelled phytoplankton cells were directly compared in surface waters of the open Atlantic Ocean (30°S to 30°N). CO2 fixation rates of Prochlorococcus are at least 1.5–2.0 times higher than CO2 fixation rates of the smallest plastidic protists and Synechococcus cyanobacteria when normalised to photosynthetic pigmentation assessed using cellular red autofluorescence. Therefore, our data indicate that in oligotrophic oceanic surface waters, pigment minimisation allows Prochlorococcus cells to harvest plentiful sunlight more effectively than other phytoplankton.