Synthesis pathway relationship between starch and fat in Chlorella sp. under nitrogen starvation

doi:10.11949/j.issn.0438-1157.20141760

Abstract

Abstract:

Triacylglycerol (TAG) and starch, as the two main energy storage products in green microalgae, especially the Chlorella sp., share the same synthesis precursor in its metabolisim system. This research aimed at the key enzymes in inhibiting starch and TAG synthesis, using Chlorella sp. as the object under nitrogen starvation. To investigate the relationship between the two metabolism pathways, comparison of TAG and starch accumulation was conducted. The starch synthesis way was significantly inhibited when 5 mmol·L^-1 Pi was added, resulting in reduced starch content and increased fatty acids concentration. While, fatty acids content per cell unit was not obviously influenced. In addition, 40 μmol·L^-1 of sethoxydim also showed starch inhibition after it had been introduced for 6 days. In this situation, starch concentration was reduced but unit cell starch content was not significantly changed.

Key words: Chlorella sp., nitrogen starvation, starch, fatty acids, inhibition, biofuel, metabolism, biotechnology

摘要：

绿藻特别是小球藻细胞存在两大储碳代谢物, 脂肪(TAG)和淀粉, 且二者的合成享有共同的前体物质。本实验以小球藻Chlorella sp.为研究对象, 在氮胁迫的条件下, 抑制淀粉合成途径的关键酶和脂肪合成途径的关键酶, 通过对比淀粉及脂肪的积累情况来探究两条代谢途径之间的关系。实验结果显示:加入5 mmol·L^-1 Pi明显抑制了淀粉合成途径, 导致淀粉含量降低, 脂肪酸浓度有所增加, 单位细胞脂肪酸无显著影响。加入40 μ mol·L^-1稀禾定在第6 d表现出对脂肪的抑制, 淀粉浓度降低, 单位细胞淀粉含量并无显著影响。

关键词: 小球藻, 氮缺乏, 淀粉, 脂肪酸, 抑制剂, 生物燃料, 代谢, 生物技术

CLC Number:

WANG Yajie, ZHU Shunni, WANG Zhongming, YUAN Zhenhong. Synthesis pathway relationship between starch and fat in Chlorella sp. under nitrogen starvation[J]. CIESC Journal, 2015, 66(6): 2189-2195.

王亚杰, 朱顺妮, 王忠铭, 袁振宏. 氮胁迫下小球藻淀粉与脂肪的合成关系[J]. 化工学报, 2015, 66(6): 2189-2195.

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