Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Department of Protists and Cyanobacteria (PuC), Braunschweig, Germany.
Helmholtz-Centre for Infection Research (HZI), Group of Genome Analytics, Braunschweig, Germany.
Genome Biol Evol. 2018 Jan 1;10(1):1-13. doi: 10.1093/gbe/evx250.
The peroxisome was the last organelle to be discovered and five decades later it is still the Cinderella of eukaryotic compartments. Peroxisomes have a crucial role in the detoxification of reactive oxygen species, the beta-oxidation of fatty acids, and the biosynthesis of etherphospholipids, and they are assumed to be present in virtually all aerobic eukaryotes. Apicomplexan parasites including the malaria and toxoplasmosis agents were described as the first group of mitochondriate protists devoid of peroxisomes. This study was initiated to reassess the distribution and evolution of peroxisomes in the superensemble Alveolata (apicomplexans, dinoflagellates, ciliates). We established transcriptome data from two chromerid algae (Chromera velia, Vitrella brassicaformis), and two dinoflagellates (Prorocentrum minimum, Perkinsus olseni) and identified the complete set of essential peroxins in all four reference species. Our comparative genome analysis provides unequivocal evidence for the presence of peroxisomes in Toxoplasma gondii and related genera. Our working hypothesis of a common peroxisomal origin of all alveolates is supported by phylogenetic analyses of essential markers such as the import receptor Pex5. Vitrella harbors the most comprehensive set of peroxisomal proteins including the catalase and the glyoxylate cycle and it is thus a promising model organism to investigate the functional role of this organelle in Apicomplexa.
过氧化物酶体是最后被发现的细胞器，五十年后，它仍然是真核生物区室中的灰姑娘。过氧化物酶体在清除活性氧、脂肪酸的β氧化以及醚磷脂的生物合成中起着至关重要的作用，几乎所有需氧真核生物都被认为存在过氧化物酶体。包括疟疾和弓形体病病原体在内的顶复门寄生虫被描述为第一批缺乏过氧化物酶体的线粒体原生动物。本研究旨在重新评估过氧化物酶体在超集 Alveolata（顶复门、甲藻、纤毛虫）中的分布和进化。我们从两种 chromerid 藻类（Chromera velia、Vitrella brassicaformis）和两种甲藻（Prorocentrum minimum、 Perkinsus olseni）建立了转录组数据，并在所有四个参考物种中鉴定了完整的必需过氧化物酶。我们的比较基因组分析为顶复门生物中过氧化物酶体的存在提供了确凿的证据。我们的工作假设是所有的 alveolates 都有一个共同的过氧化物酶体起源，这一假设得到了必需标记物（如进口受体 Pex5）的系统发育分析的支持。Vitrella 拥有最全面的过氧化物酶体蛋白组，包括过氧化氢酶和乙醛酸循环，因此它是研究这个细胞器在顶复门中的功能作用的有前途的模式生物。
