Dei-Cas Eduardo, Chabé Magali, Moukhlis Raya, Durand-Joly Isabelle, Aliouat El Moukhtar, Stringer James R, Cushion Melanie, Noël Christophe, de Hoog G Sybren, Guillot Jacques, Viscogliosi Eric
ECOPA (EA 3609), Lille Pasteur Institute, Lille, France.
FEMS Microbiol Rev. 2006 Nov;30(6):853-71. doi: 10.1111/j.1574-6976.2006.00037.x.
The genus Pneumocystis comprises noncultivable, highly diversified fungal pathogens dwelling in the lungs of mammals. The genus includes numerous host-species-specific species that are able to induce severe pneumonitis, especially in severely immunocompromised hosts. Pneumocystis organisms attach specifically to type-1 epithelial alveolar cells, showing a high level of subtle and efficient adaptation to the alveolar microenvironment. Pneumocystis species show little difference at the light microscopy level but DNA sequences of Pneumocystis from humans, other primates, rodents, rabbits, insectivores and other mammals present a host-species-related marked divergence. Consistently, selective infectivity could be proven by cross-infection experiments. Furthermore, phylogeny among primate Pneumocystis species was correlated with the phylogeny of their hosts. This observation suggested that cophylogeny could explain both the current distribution of pathogens in their hosts and the speciation. Thus, molecular, ultrastructural and biological differences among organisms from different mammals strengthen the view of multiple species existing within the genus Pneumocystis. The following species were subsequently described: Pneumocystis jirovecii in humans, Pneumocystis carinii and Pneumocystis wakefieldiae in rats, and Pneumocystis murina in mice. The present work focuses on Pneumocystis oryctolagi sp. nov. from Old-World rabbits. This new species has been described on the basis of both biological and phylogenetic species concepts.
肺孢子菌属包含寄居于哺乳动物肺部、不可培养且高度多样化的真菌病原体。该属包括众多宿主物种特异性的物种，这些物种能够引发严重的肺炎，尤其是在严重免疫功能低下的宿主中。肺孢子菌生物体特异性地附着于1型肺泡上皮细胞，显示出对肺泡微环境高度精细且有效的适应性。肺孢子菌物种在光学显微镜水平上差异不大，但来自人类、其他灵长类动物、啮齿动物、兔子、食虫动物和其他哺乳动物的肺孢子菌的DNA序列呈现出与宿主物种相关的显著差异。一致地，交叉感染实验能够证明选择性感染性。此外，灵长类肺孢子菌物种之间的系统发育与它们宿主的系统发育相关。这一观察结果表明，协同进化可以解释病原体在其宿主中的当前分布以及物种形成。因此，来自不同哺乳动物的生物体之间的分子、超微结构和生物学差异强化了肺孢子菌属内存在多个物种的观点。随后描述了以下物种：人类的耶氏肺孢子菌、大鼠的卡氏肺孢子菌和韦氏肺孢子菌，以及小鼠的鼠肺孢子菌。目前的工作聚焦于来自旧大陆兔的新物种——兔肺孢子菌。这个新物种是基于生物学和系统发育物种概念描述的。
