期刊
BIOMOLECULAR ENGINEERING
卷 20, 期 4-6, 页码 199-203出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/S1389-0344(03)00053-4
关键词
Chlamydomonas reinhardtii; Cd2+ toxicity; S-starvation; sulfate assimilation
Cadmium (Cd2+) or copper (Cu2+) ions are toxic for Chlamydomonas reinhardtii growth, at 300 muM, and the alga may accumulate about 0.90+/-0.02 and 0.64+/-0.02% of its dry weight, respectively. Metal contamination changes the elemental composition of dried alga biomass, which indicates the possibility to use C reinhardtii as biosensor and bioremediator of the aquatic contamination by heavy metals. Either, Cd2+ or Cu2+, inhibits about 20% of the nitrate consumption rate by the cells, while only Cd2+ increases about 40% the sulfate consumption rate. The presence of 1 mM calcium (Ca2+) in the culture medium increases the C reinhardtii productivity (about 50%), the nitrate uptake rate (about 20%) and the sulfate uptake rate (about 30%). In addition, Ca2+ overcomes the Cd2+ (300 muM) toxicity by decreasing (about 35%) the intracellular accumulation of metal. Sulfur-starvation induces in C. reinhardtii the expression of serine acetyltransferase and O-acetylserine(thiol)lyase activities, but decreases 50% the consumption rate of nitrate by the cells. Sulfate is also required for the full expression of the nitrate reductase (NR), nitrite reductase (NiR) and glutamate synthase activities. (C) 2003 Elsevier Science B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据