Powell M J, Lehnen L P, Bortnick R N
Biosystems. 1985;18(3-4):321-34. doi: 10.1016/0303-2647(85)90032-2.
Zoospores of Oomycetes contain a variety of microbody-like organelles with highly structured matrices. Although in general their function is unknown, the appearance of similar organelles in related taxa suggests the ultrastructural differences could be used as taxonomic characters. This study surveys microbody-like organelles of oomycetous zoospores to determine if this is an additional criterion by which the phylogeny of these fungi can be evaluated. In zoospores of the order Saprolegniales, kinetosome-associated organelles (K-bodies) are found which typically consist of tubular and/or granular matrices. K-bodies are not found associated with kinetosomes in zoospores of the Peronosporales, but microbodies containing tubules, and in some genera marginal plates, are located near the kinetosomes, along the groove, and in other peripheral areas. K-bodies have been reported in only one member of the order Lagenidiales. These K-bodies lack a granular matrix, but contain a single curved plate from which tubules arise, forming a cone. In the one genus of the Leptomitales examined, a similar K-body contains a plate and scattered tubules. Organisms with similar microbody-like organelles are probably more closely related than those with different types of microbody-like organelles. The presence of an organelle resembling K-bodies in zoospores of an alga in the Tribophyceae supports the phylogenetic association between algae and Oomycetes. A complete survey of Oomycete genera may well reveal intermediates between the structurally different types of microbody-like organelles, allowing the reconstruction of the phylogenetic history of an organelle.
卵菌纲的游动孢子含有多种具有高度结构化基质的类微体细胞器。尽管其功能通常未知，但相关分类群中类似细胞器的出现表明，超微结构差异可作为分类特征。本研究调查了卵菌纲游动孢子的类微体细胞器，以确定这是否是评估这些真菌系统发育的另一个标准。在水霉目游动孢子中，发现了动基体相关细胞器（K体），其通常由管状和/或颗粒状基质组成。在霜霉目游动孢子中，未发现K体与动基体相关，但含有微管的微体，在一些属中还有边缘板，位于动基体附近、沿着沟以及其他周边区域。仅在链壶菌目中的一个成员中报道过K体。这些K体缺乏颗粒状基质，但含有一个单一的弯曲板，从中生出微管，形成一个锥体。在所研究的薄囊霉目中的一个属中，类似的K体含有一个板和散在的微管。具有类似类微体细胞器的生物可能比具有不同类型类微体细胞器的生物关系更密切。在三毛藻科一种藻类的游动孢子中存在类似K体的细胞器，支持了藻类和卵菌纲之间的系统发育关联。对卵菌纲各属进行全面调查很可能会揭示结构不同类型的类微体细胞器之间的中间类型，从而有助于重建一种细胞器的系统发育历史。
