Spencer R, Cross G A
Biochim Biophys Acta. 1975 May 1;390(2):141-54. doi: 10.1016/0005-2787(75)90337-8.
A simple, rapid method for preparing bipolar bodies from sonicated (rithidia oncopelti cells, with a yield of 2-5%, is described. Apart from 2-4% contamination with unbroken cells the fraction was considered pure with respect to contamination by other nucleic acid-containing organelles, as judged by light and electron microscopy. A light satellite DNA, f bouyant density 1.695 g/ml in neutral CsCl, and derived from the bipolar body, had a Tm of 81.6 degrees C in0.15 M NaCl/0.015 M sodium citrate (pH 7.0) and a kinetic complexity of 2.7 with 109. The bipolar body fraction also contained ribonucleoprotein particles with and s20,w of 67 S, in contrast to cytoplasmic ribosomes (87 S). Bipolar body ribosomes contained rRNA components which migraged coincidentally with Escherichia coli rRNA (molecular weights 1.07 with 10-6 and 0.56 with 10-6) on polyacrylamide gel electrophoresis. Cytoplasmic ribosomes contained rRNAs of molecular weights 1.30 with 10-6 and 0.83 with 10-6. Bipolar body rRNA accounted for up to 10% of the rRNA extracted from cells. The properties of these bipolar body nucleic acids provide good evidence for the bacterial nature of this subcellular component.
描述了一种从经超声处理的（利什曼原虫Oncopelti细胞）制备双极体的简单、快速方法，产率为2 - 5%。除了有2 - 4%未破碎细胞的污染外，根据光学和电子显微镜判断，该组分相对于其他含核酸细胞器的污染被认为是纯的。一种轻卫星DNA，在中性CsCl中的浮力密度为1.695 g/ml，来源于双极体，在0.15 M NaCl/0.015 M柠檬酸钠（pH 7.0）中的熔解温度为81.6℃，动力学复杂度为2.7×10⁹。双极体组分还含有沉降系数s₂₀,w为67 S的核糖核蛋白颗粒，与细胞质核糖体（87 S）不同。双极体核糖体含有的rRNA组分在聚丙烯酰胺凝胶电泳上与大肠杆菌rRNA（分子量分别为1.07×10⁻⁶和0.56×10⁻⁶）迁移一致。细胞质核糖体含有的rRNA分子量分别为1.30×10⁻⁶和0.83×10⁻⁶。双极体rRNA占从细胞中提取的rRNA的比例高达10%。这些双极体核酸的特性为该亚细胞组分的细菌性质提供了有力证据。
