Department of Pathology, Division of Tropical Medicine and Parasitology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Microbes Infect. 2012 Apr;14(4):324-8. doi: 10.1016/j.micinf.2011.11.010. Epub 2011 Nov 28.
The microsporidia are emerging human and veterinary pathogens known to infect every tissue type and organ system. Their infectious spore possesses a number of peculiar organelles, including the diagnostic polar tube. In a proteomics-driven effort to find novel components of this organelle in the human-pathogenic species Encephalitozoon cuniculi, we unexpectedly discovered a protein which localizes to punctate structures consistent with the appearance of relic mitochondria, or mitosomes. However, this novel protein did not colocalize with ferredoxin, a mitochondrial iron-sulfur cluster protein which shows a similar localization pattern by light microscopy. The distribution pattern of this protein thus suggests either a novel vesicular compartment that is similar to mitosomes in size and distribution, the presence of subdomains or branching architecture within mitosomes, or heterogeneity in the protein composition of E. cuniculi mitosomes.
微孢子虫是新兴的人兽共患病原体，已知可感染所有组织类型和器官系统。它们的感染孢子具有许多特殊的细胞器，包括诊断性极管。在一项蛋白质组学驱动的研究中，我们试图在人类致病种——兔脑炎微孢子虫中寻找该细胞器的新型成分，却意外地发现了一种定位于点状结构的蛋白质，这些结构与残留线粒体或线粒体类似。然而，这种新型蛋白质与铁氧还蛋白（一种线粒体铁硫簇蛋白）没有共定位，后者通过光镜显示出相似的定位模式。因此，这种蛋白质的分布模式表明存在一种新型的囊泡结构，其在大小和分布上与线粒体类似，线粒体内部存在亚域或分支结构，或者兔脑炎微孢子虫线粒体的蛋白质组成存在异质性。
