In the Arctic Ocean, the small green alga Micromonas polaris dominates pico-phytoplankton during the summer months. It has been previously hypothesized to be phago-mixotrophic (capable of bacteria ingestion) based on laboratory and field experiments. Prey uptake was analysed in several M. polaris strains isolated from different regions and depths of the Arctic Ocean. Using both fluorescent beads and fluorescently labelled bacteria as prey, we found no evidence of phago-mixotrophy in any M. polaris strain by flow cytometric measurement of prey ingestion. In addition, in silico predictions reveal that members of the genus Micromonas lack a genetic signature of phagocytotic capacity.

中文翻译：

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没有证据表明北极极微微浮游植物极地微孢子菌具有吞噬多向性。

在北冰洋，夏季夏季，小绿藻极地微藻（Micromonas polaris）主导着浮游植物。根据实验室和野外实验，以前假设它是吞噬营养的（能够吞噬细菌）。分析了从北冰洋不同地区和不同深度分离出的几种北极孢菌株的猎物摄取情况。使用荧光珠和荧光标记的细菌作为猎物，通过流式细胞术测量猎物的摄入量，我们没有发现任何北极星分枝杆菌菌株具有吞噬混合营养的迹象。另外，计算机预测表明，微单胞菌属的成员缺乏吞噬能力的遗传特征。