High uptake of malate and efficient distribution of intracellular malate to organelles contributed to biomass increase, reducing maintenance energy. In this study, transgenic Chlamydomonas reinhardtii was developed that stably expresses malate synthase in the chloroplast. The strains under glyoxylate treatment showed 19% more increase in microalgal biomass than wild-type. By RNA analysis, transcript levels of malate dehydrogenase (MDH4) and acetyl-CoA synthetase (ACS3), isocitrate lyase (ICL1) and malate synthase (MAS1), were significantly more expressed (17%, 42%, 24%, and 18% respectively), which was consistent with reported heterotrophic metabolism flux analysis with the objective function maximizing biomass. Photosynthetic F_v/F_m was slightly reduced. A more meticulous analysis is necessary, but, in the transgenic microalgae with malate synthase overexpression, the metabolism is likely to more rely on heterotrophic energy production via TCA cycle and glyoxylate shunt than on photosynthesis, resulting in the increase in microalgal biomass.

苹果酸的高吸收和细胞内苹果酸向细胞器的有效分布促进了生物量的增加，从而降低了维持能量。在这项研究中，开发了可在叶绿体中稳定表达苹果酸合酶的转基因衣藻。乙醛酸处理的菌株显示微藻生物量比野生型增加19％。通过RNA分析，苹果酸脱氢酶（的转录物水平MDH4）和乙酰-CoA合成酶（ACS3），异柠檬酸裂合酶（ICL1）和苹果酸合酶（MAS1）的表达量更高（分别为17％，42％，24％和18％），这与报道的异养代谢通量分析一致，目标功能是最大化生物量。光合F _v / F _m略有降低。需要进行更加细致的分析，但是，在苹果酸合酶过度表达的转基因微藻中，新陈代谢可能更依赖于通过TCA循环和乙醛酸分流产生的异养能量，而不是光合作用，从而导致微藻生物量的增加。