Origin of Eukaryotic Algae from a view point of chloroplast nucleoids in Cyanidium.

从原核生物到真核生物的进化，从内生共生说到直接丝化说已经讨论了很长时间。我们最近的实验任务可以从细胞结构的真核程度的角度为这一讨论提供材料。其中蓝藻RK-1具有细胞核、叶绿体和线粒体，是真核生物中最重要的生物之一，在真核生物中处于最低的分类地位。在本研究中，我们使用DAPI染色和包括VIM系统在内的荧光显微镜，测定了细胞核和叶绿体类核中的DNA含量。将这些数据与其他原核生物和真核生物进行了比较，荧光显微镜测定的类核面积与单个细胞大小的比率在蓝藻中表现出极高的水平。但由光子计数器测定的每一个细胞的DNA含量在其他微藻中呈现出平均值。光子数cou…VIM系统的检测结果似乎与DNA含量几乎成正比。用这种方法计算的蓝藻细胞细胞核中的DNA含量比其他藻类细胞的DNA含量要少得多。但单个细胞的DNA含量根据其小细胞的大小呈现出平均值。细胞器类核与核的DNA比率显著地表明了真核进化的程度。RK-1的平均值为0.378，包括0.198(年轻细胞)到0.454(老化细胞)。此外，M-8菌株在光培养的年轻细胞中的值为1.247，在暗生长的年轻细胞中的值为0.308。结果表明，RK-1菌株因其杆状叶绿体类核(CN-型)而与蓝藻类群相似，而M-8菌株因其环状叶绿体类核(CL型)而与褐藻或硅藻类群相似。这些结果表明，两株蓝藻之间存在着相当大的差异，而蓝藻RK-1类型可能是微藻中独一无二的，因为它含有大量的奇数碳数正构烷酸。较少

The evolution from Prokaryote to Eukaryote has been discussed a long time between Endosymbiotic Theory and Direct Filiation Theory. The present task on our recent trials could offered a material for this discussion from a view point of eukaryotic degree of cell structure. Among them, Cyaniaium caldarium RK-1 which possesses each one of nucleus, chloroplast, and mitochondrion, is one of the most important organisms as is situated in the lowest taxonomic position of Eukaryote. In the present study we used DAPI staining and Fluorescence Microscopy including VIM-system, and determined the DNA contents in the nucleus and chloroplast nucleoids. These data were compared with other Prokaryotic and Eukaryotic organisms.The ratios of nucleoids area to single cell size determined by Fluorescence Microscopy presented exceeding high levels in Blue Green Algae. But the DNA contents per single cell determined by a photon counter presented the average values among other mocro-algae. Photon numbers cou … More nted with VIM-system seem almost proportional to DNA contents exactly. DNA in the nucleus of Cyanidium cells counted by this method indicate considerable small amounts than those of other algal cells. But the DNA contents per single cell presented about an average value according to their small cell sizes.DNA ratio of organelle nucleoid to nucleus significantly suggests to be an indicator of Eukaryotic degree in evolution. RK-1 has an average value of 0.378 which includes from 0.198(young cells) to 0.454(aged cells). Otherwise M-8 strain presented a value of 1.247 in light grown young cells, and 0.308 in dark grown young cells, respectively. We presented the result that RK-1 strain resembles to Cyanophyta type because of its rod shaped chloroplast nucleoid(CN-type), on the other hand M-8 strain resembles to Phaeophyt or Bacillariophyta bacause of its ring shaped chloroplast nucleoid(CL-type).Gaschromatographic analyses of hydrocarbons and fatty acids in two strains of Cyanidium caldarium were carried out. These results indicate a considerable difference between the two strains of Cyanidium caldarium,and Cyanidium RK-1 type may be unique among microalgae because it has a significant amount of odd-carbon numbered n-alkanoic acids. Less