小球藻产三酰甘油过程的代谢途径分析

Metabolic pathway analysis on enhanced TAG production of Chlorella

以基因工程强化微藻三酰甘油(TAG)积累是实现微藻生物柴油应用化的途径之一。为进行有效的基因工程操作,研究分析了微藻代谢网络,以找出其中对TAG合成重要的反应。构建了异养及自养条件下小球藻产TAG过程核心代谢网络。采用改进CASOP(Computational approach for strain optimization aiming at high productivity)法分析网络中各反应的重要度。结果表明,主要的关键反应包括脂肪酸和TAG的合成反应以及提供NADPH的反应,特别是将NADH转化为NADPH的反应。此外,分析结果也部分解释了环境压力对TAG积累的作用。

Enhanced triacylglycerol （TAG） accumulation of microalgae with genetic engineering will contribute to the application of algal biodiesel. In order to perform effective genetic engineering, the analysis on the metabolic network of oleaginous algae is carried out to obtain the important reactions for TAG production. The central metabolic networks of TAG producing chlorella under both heterotrophic and autotrophic conditions are reconstructed in this study. A modified CASOP （computational approach for strain optimization aiming at high productivity） method is introduced to evaluate the importance of each reactions in the metabolic networks. The results show that the most important reactions are those producing fatty acid, TAG and NADPH, especially those converting NADH into NADPH, which partly explains the effect of environmental stress on TAG accumulation.