Vasquez C C, Mora G
Arch Biol Med Exp. 1979 Oct;12(3):367-72.
Two types of cytoplasmic ribosomes of Euglena gracilis have been found when the stability in vitro of the large subunit at 25 degrees C for 30 min has been considered. Sucrose density gradient analysis have revealed that the large subunit of ribosomes obtained from cells harvested in the stationary phase of growth was degraded when heated at 25 degrees C. The large subunit of ribosomes obtained from exponentially growing cells was stable in the same experimental conditions. Studies of the ribosomal RNAs have not explained this differential stability observed in vitro. In fact, after SDS-extraction, the largest RNA species always appears degraded in both types of ribosomes. Therefore, an explanation to this phenomenon have been searched for through the analysis of the ribosomal proteins. One and two dimensional gel electrophoresis techniques have been employed. At least one difference between the two ribosomal protein groups has been observed and this could be associated to the differential stability of the ribosomes. Approximately 72 proteins molecules have been found in Euglena's cytoplasmic ribosome. About 42 proteins belong to the large subunit and 30 to the small one.
当考虑到大亚基在25℃下体外稳定性30分钟时，发现了纤细裸藻的两种类型的细胞质核糖体。蔗糖密度梯度分析表明，从生长稳定期收获的细胞中获得的核糖体大亚基在25℃加热时会降解。在相同实验条件下，从指数生长期细胞中获得的核糖体大亚基是稳定的。核糖体RNA的研究尚未解释在体外观察到的这种差异稳定性。事实上，SDS提取后，两种类型的核糖体中最大的RNA种类似乎总是降解的。因此，通过对核糖体蛋白质的分析来寻找这种现象的解释。采用了一维和二维凝胶电泳技术。观察到两个核糖体蛋白质组之间至少有一个差异，这可能与核糖体的差异稳定性有关。在裸藻的细胞质核糖体中发现了大约72个蛋白质分子。大约42个蛋白质属于大亚基，30个属于小亚基。
