Zn^(2+)浓度对固氮鱼腥藻(Anabaena azotica Ley)光能转化特性的影响  

Effects of Zinc Ion on Photosynthetic System of Anabaena azotica Ley

作　　者：王山杉[1] 刘永定[1] 金传荫[1] 李敦海[1] 

机构地区：[1]中国科学院水生生物研究所,武汉430072

出　　处：《湖泊科学》2002年第4期350-356,共7页Journal of Lake Sciences

基　　金：国家湖泊重点研究课题(K99-05-35-01)资助;中国科学院水生生物研究所创新领域前沿项目(220316)资助

摘　　要：本实验对在不同Zn2+浓度条件下培养的固氮鱼腥藻(Anabaena azoticaLey)的生长、光合放氧速率和叶绿素荧光参数Fv/Fm进行了测定.结果表明,当Zn2+浓度为1.0μmol/L时,其比生长速率(Specific growth rate)最大,光合放氧速率和Fv/Fm值最高.当Zn2+浓度大于等于5.0μmol/L时会抑制A.azotica Ley的生长和光合作用.对在0μmol/L和5.0μmol/L Zn2+浓度下生长的藻细胞藻胆体-类囊体膜复合物吸收光谱的比较和对与5.0μmol/L Zn2+发生反应的藻蓝蛋白溶液的可见光吸收光谱的分析,发现前者624nm处藻胆体的吸收峰和后者620nm处藻蓝蛋白的吸收峰都因Zn2+的作用而下降,推测藻蓝蛋白为Zn2+影响光合作用的位点之一.碳酸酐酶活性的测定表明Zn2+的浓度水平会影响其活性大小,推测是Zn2+影响光合作用的另一途径.It was found that the concentration of Zn2+ at about 1. 0mol/L was essential to keep optimal growth of Anabaena azotica Ley and also important to keep a quite high value of photosynthetic oxygen evolution rate, chlorophyll fluorescence (Fv/Fm) level and carbonic anhydrase activity, whereas the relative high concentration of Zn2+(>5. 0um) would inhibit the growth of A. azotica Ley, decrease its photosynthetic oxygen evolution rate, chlorophyll fluorescence and CA activity. The study of the absorption spectra of the phycobilisome-thy-lakoid membrane complex and the extraction of phycocyanin indicate that Zn2+ may affect the photosynthesis by its effect on the phycobilisome especially the phycocyanin. Since CA is a Zn2+-containing metalloenzyme and may provide a high concentration of CO2 to Rubisco in the process of CO2 fixation, it is suggested that Zn2+ may affect the photosynthesis by acting on CA.

关 键 词：固氮鱼腥藻 锌离子 光合作用 藻蓝蛋白 碳酸酐酶 重金属污染 水污染 

分 类 号：X173[环境科学与工程—环境科学]