真蓝甲藻(Gymnodinium eucyanochroum Tseng Sp.nov.)的亚微结构、色素性质及其在藻类进化中的意义

本文报告了在南京发现的蓝色裸甲藻,测定了它的藻胆色素。证明蓝色藻胆蛋白不是山“胞内蓝藻”(Cyanellen)所提供。电子显微镜的扫描表明细胞表面有众多的突起,不是光滑的;横沟内的鞭毛不是“带状”而是由细纤维丝膜状物拉着的螺旋形。透视电子显微镜观察表明,该藻有两个类型的细胞核,即“甲藻核结构”(Dinocaryotic structure)和“真核结构”,(Eucaryotic Structure),真核与叶绿体有一个共同的膜的包被,有一个与原生动物相近似的伸缩泡系统。叶绿体是分枝状,在细胞的边缘位,但也有其它形态。有淀粉颗粒而无“造粉核”或称”“蛋白核”(Pyrenoid),多数位于叶绿体外或之间,类囊体与一般甲藻不同,不是三个排成一条“带”而是两个排列成“带”。有发达的线粒体,和高尔基体;鞭毛不论纵沟内的或横沟内的,其横切面,均为9+2的形式,其纵切面是由纤维丝成束的结构。蓝色色素提取物,可见光最大吸收峰为456nm,与隐藻藻胆色素十分相似。从细胞亚微结构及其色素性质,作者认为它是藻类演化过程中的一个中间类型的甲藻共生体。

PIGMENT ASSAY AND ULTRASTRUCTURAL OBSERVATION ON GYMNODINIUM EUCYANOCHROUM Sp.NOV.(PYRRHOPHYCOPHYTA)

Among the phytoplankton samples collected between May and June in 1979 from a high-yielding fish pond near the Yangtze River Bridge we have discovered a blue-green specimen of the genus Gymnodinium Absorption, fluorescence emission and excitation spectra have proved that the blue substance is a Phycocyanin much like the Cryptomonad 645 PC. (Fig. 4 ) Bohyslav Fott(1971) pointed out that the blue-green material was an intracellular "Cyanellen" as found in Gymnodinium aeruginosum. However, in the electronic microphotographs, so far no "Cyanellen" has been found except the lamellae structure in chloroplast which is the same as in phycocyanincontaining Cryptomond. The number of thylakoids per lamella is 2, the same as that in the chloroplast of Cryptophyta, but not the same as that in the Pyrrhophycophyta where the number is 3. (Fig. 20. C.D) Of the two kinds of nuclei one has the typical structure of dinocaryotic dinoflagellates and the other possesses some characteritsics typical of the nucleus of eucaryotic organisms. (Fig.14)The eucaryotic nucleus is surrounded by a double membrane but it seems to share another common membrane with the chloroplast which has its own envelope and might probably be endosymbiont as R. N, Tomas and Elenor R. Cox. (1973) reported. In both longitudineal and cross-sections,the cell appears to be of "Helianthus annuus-shaped" structure, which is quite similar to the contractile vacules of Paramoecium. The Mitochondria is very large whereas the Golgi apparatus is relatively small. As Gymnodinium eucyanochroum has some original characteristics,we believe that it is a transitional type in the algae evolution