摘要
藻类分子生物学和基因工程的发展已使外源基因能在蓝藻中表达,这就有可能分析外源基因对光合作用的影响。本研究采用两种转化系统所得的转基因蓝藻(Anabaena sp.PCC7120)1(To1)、2(To2)及野生藻(Wo)测定其生长曲线表明,它们的生长速度比较接近,转基因藻略微缓慢,生物量也偏少。用氧电极测定转基因藻的饱和光强与野生藻接近,为480μEm^(-2)s^(-1),最大放氧量为355mol O_2/mg Chl.h.吸收光谱测定结果表明转基因藻与野生藻的色素组成一致,均含有叶绿素a、类胡萝卜素和藻蓝蛋白等,但T02的藻胆蛋白含量高于野生藻。低温荧光发射光谱测定表明,外源基因的导入及表达促进了转基因藻中藻蓝蛋白的合成,改变了光能在两个光系统之间的分配,特别是由藻胆蛋白吸收的光能向光系统Ⅰ的传递受阻,不同的转化系统中所得的转基因藻中表现程度亦有差异。
The foreign genes have expressed in cyanobacteria, since the moleculor biology and gene engineering have developed. This make it possible to analyze the effects of foreign gene on the photosynthesis of cyanobacteria cells. Three types of cells, wild type cells of Anabaena sp. PCC 7120, and its transgenic cells To1 and To2, which came from two different transforming systems, were used in this work. It showed that the growth rates of transgenic cells were smaller than thoste of the wild type. The saturation light intensity of transgenic cells was 480μEm-2s-1 which was similar to that of wild type cells, The maximum oxygen evolution rate was about 360umolO2/mg Chl·hr. The absorption spectra showed that all of them had the chl a, carotenoid and phycocyanin. The phycocyanin content in one type of transgenic cells (To2) was much higher than that of wild types cell and To1. The low temperature fluorescence emission spectra results displayed that the energy transfer from phycob-iliprotein to photosystem I in transgenic cells was decreased, and the effects were also different in two types of transgenic cells.
出处
《水生生物学报》
CAS
CSCD
北大核心
1999年第5期475-480,共6页
Acta Hydrobiologica Sinica
基金
国家863海洋生物高技术青年基金项目资助
