铜锈微囊藻两种表型的生长生理特性及毒素组成比较分析

从滇池蓝藻水华中分离得到的铜锈微囊藻群体在实验室无机营养中解聚成单细胞，结果表明，群体微囊藻的生长速度明显低于单细胞微囊藻；前者具明显可见的胞外酸性多交鞘，而单细胞则几乎没有；按常规方法分析比较两种细胞形态的毒性大小和毒素组成，发现群体微囊藻主要含有三种微囊藻毒素的异构件，而单细胞以MC－LR为主；且单细胞微囊藻的毒性约为群体的1倍。二者的LDH和PGM同工酶酶谱也有差异。本研究为解释毒素的合成和调控机理提供了新的证据。

COMPARISON OF GROWTH AND TOXIN ANALYSIS IN TWO PHENOTYPE MICROCYSTIS AERUGINOSA

Colonial Microcystis aeruginosa isolated from water bloom of Dianchi Lake lost its colonial type and became single celled type upon continuous subcultured in inorganic medium. It was observed that the growth rate of colonial M.aeruginosa was markedly lower than that of single cell; the extracellular acid polysaccharide capsule was obviously visible in the colonial type but was absent in the single celled one; toxin analysis indicated that three microcystins isomers were produced in colonial M. aeruginosa, but in single celled M. aeruginosa, only one major toxin MC LR was detected; sing celled M. aeruginosa had the LD 50 value almost ten times higher than colonial M. aeruginosa. Allozyme divergence was detected, too. The study has brought forward a new proof to explanation of mechanisms on regulation of microcystin synthesis.