Fiskin A M, Garrison R G
Research Service, Veterans Administration Medical Center, Kansas City, MO 64128.
Ann Inst Pasteur Microbiol (1985). 1986 Jan-Feb;137A(1):15-31. doi: 10.1016/s0769-2609(86)80002-3.
A concomitant but transient occurrence of large numbers of double-membraned vesicles with immature, culturally induced microbodies was demonstrated in thin sections of Basidiobolus haptosporus soon after transfer of the fungus to a defined medium containing xanthine or its catabolites as the sole source of nitrogen. Double-membraned vesicles were rapidly formed as derivatives of endoplasmic cisternae later to occur free in the cytoplasm, often as the most predominant cytoplasmic inclusion. Densitometric measurements revealed that heavy metal-binding cytoplasmic constituents were concentrated within the vesicular lumen. Most of the double-membraned vesicles appeared to undergo degeneration; they were rare to absent in thin sections of older cells. At times, double-membraned vesicles were seen connected to newly formed microbodies in a manner suggesting ontogenic relationships. The outer vesicular membrane was continuous with the single limiting membrane of the microbody via a short tubule. We interpret these observations as empirical ultrastructural evidence to suggest that some double-membraned vesicles become specialized and function as precursor inclusions in the biogenesis of new microbody populations committed to purine salvage.
将担子菌纲的哈氏担子菌转移至含有黄嘌呤或其分解代谢产物作为唯一氮源的特定培养基后不久，在其薄片中发现大量双膜囊泡与未成熟的、培养诱导产生的微体同时出现，但这种情况是短暂的。双膜囊泡作为内质网池的衍生物迅速形成，随后游离于细胞质中，常常是细胞质中最主要的内含物。密度测量显示，与重金属结合的细胞质成分集中在囊泡腔内。大多数双膜囊泡似乎会发生退化；在较老细胞的薄片中很少见到或根本没有。有时，可以看到双膜囊泡以一种暗示发生学关系的方式与新形成的微体相连。囊泡的外膜通过短管与微体的单一限制膜相连。我们将这些观察结果解释为经验性的超微结构证据，表明一些双膜囊泡变得特化，并在致力于嘌呤补救的新微体群体的生物发生中作为前体内含物发挥作用。
