Eukaryotic microbes (protists) that occupy low-oxygen environments often have drastically different mitochondrial metabolism compared to their aerobic relatives. A common theme among many anaerobic protists is the serial loss of components of the electron transport chain (ETC). Here, we discuss the diversity of the ETC across the tree of eukaryotes and review hypotheses for how ETCs are modified, and ultimately lost, in protists. We find that while protists have converged to some of the same metabolism as anaerobic animals, there are clear protist-specific strategies to thrive without oxygen.

中文翻译：

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厌氧生物中电子传输链的多样性

与有氧亲戚相比，占据低氧环境的真核微生物（原生生物）通常具有明显不同的线粒体代谢。在许多厌氧生物中，一个共同的主题是电子传输链（ETC）的成分连续损失。在这里，我们讨论了整个真核生物中ETC的多样性，并回顾了有关ETC如何在原始生物中被修改并最终消失的假设。我们发现，尽管原生生物已经收敛到与厌氧动物相同的新陈代谢，但是有明确的针对原生生物的策略可以在没有氧气的情况下壮成长。