聚球藻7942光自养培养的碳代谢和能量代谢

Carbon and energetic metabolism of Synechococcus sp.PCC7942 under photoautotrophic conditions

代谢通量分析是研究微藻光自养培养过程中CO2和光能利用的一个非常有用的工具。本研究建立了聚球藻7942光自养培养代谢网络,并通过代谢通量方法分析了不同入射光强下的碳代谢流分布和能量代谢。研究结果表明,CO2固定是代谢能量和还原力消耗的主要途径,分别约占总消耗能量的85%和70%。研究还发现在一定光强范围,基于ATP生成的细胞得率和最大细胞得率基本维持不变,分别约为2.80g/molATP和2.95g/molATP,但基于总吸收光能的细胞得率和对应的光能转换效率则随着光强的增加而降低。

Metabolic flux analysis is a very powerful tool to understand CO2 fixation and light energy utilization of microalgae during photoautotrophic cultivation. A comprehensive network structure for the autotrophic growth of Synechococcus sp. PCC7942 was proposed, and the carbon and energetic metabolism under different incident light intensity was investigated based on metabolic flux analysis in this paper. These results showed that CO2 fixation was the main energy and reducing potential trap which accounted for 85% and 70% of the total energy and reducing potential consumption respectively. We also found that the cell yield and the maximum cell yield based on ATP synthesis were maintained 2.80 g/tool and 2.97 g/mol respectively under the appointed incident intensity. But the cell yield on absorbed light energy their corresponding energy conversion efficiency were descended with the increasing of incident intensity.