盐藻硝酸还原酶的盐适应性及其与物质积累的关系

Relationship between Adaptability of Nitrate Reductase to NaCl Stress and Substance Metabolism in Green AlgaDunaliella salina

为探索盐藻硝酸还原酶的盐适应性及其与物质积累的关系,研究了不同质量浓度的氯化钠培养盐藻的生理生化变化。试验结果表明,氯化钠质量浓度为40～120g/L时,盐藻硝酸还原酶活性与盐度具有正相关性;氯化钠质量浓度为120～200g/L时,盐藻硝酸还原酶活性与盐度具有负相关性;氯化钠质量浓度为120g/L时,盐藻硝酸还原酶活性最高。盐藻硝酸还原酶是一种高盐适应酶。盐藻硝酸还原酶活性与盐藻细胞密度、叶绿素形成和蛋白质积累均呈正相关关系。在盐藻硝酸还原酶活性最高时,盐藻物质积累量最多。

The physiological changes were determined in green alga Dunaliella salina cultivated under various NaC1 stress to evaluate the relationship between adaptability of nitrate reductase （NR） to NaCI stress and the substance metabolism in the alga under different salinities. The results showed that the NR activity was positively correlated with NaC1 concentration within NaC1 concentration from 40 g/L to 120 g/ L, but the NR activity was negatively correlated with NaC1 level within the NaC1 concentration from 120 g/L to 200 g/L, with the maximal NR activity at NaC1 concentration of 120 g/L, indicating that the NR in D. salina is a kind of enzymes which can adapt well to NaCI stress. The NR activity in the green alga was shown to have a positive relationship with cell density, chlorophyll formation, and accumulation of protein, the maximal substance accumulation being observed at the maximal NR activity.