Bioremediation with genetically modified microalgae is becoming an alternative to remove metalloids and metals such as cadmium, a contaminant produced in industrial processes and found in domestic waste. Its removal is important in several countries including Mexico, where the San Luis Potosi region has elevated levels of it. We generated a construct with a synthetic gene for γ-glutamylcysteine synthetase and employed it in the chloroplast transformation of Chlamydomonas reinhardtii. In dose-response kinetics with media containing from 1 to 20 mg/L of cadmium, both the transplastomic clone and the wild-type strain grew similarly, but the former removed up to 32% more cadmium. While the growth of both decreased with higher concentrations of cadmium, the transplastomic clone removed 20 ± 9% more than the wild-type strain. Compared to the wild-type strain, in the transplastomic clone the activity of glutathione S-transferase and the intracellular glutathione increased up to 2.1 and 1.9 times, respectively, in media with 2.5 and 10 mg/mL of cadmium. While 20 mg/L of cadmium inhibited the growth of both, the transplastomic clone gradually duplicated. These results confirm the expression of the synthetic gene gshA in the transformed strain as revealed in its increased removal uptake and metabolic response.

用转基因微藻进行生物修复正成为去除准金属和金属（例如镉）的替代方法，镉是工业过程中产生的污染物，并存在于生活垃圾中。在包括墨西哥在内的几个国家，圣路易斯波托西地区的水平都很高，因此清除它很重要。我们生成了带有合成的γ-谷氨酰半胱氨酸合成酶基因的构建体，并将其用于莱茵衣藻的叶绿体转化。在含有1至20 mg / L镉的培养基的剂量反应动力学中，转质体克隆和野生型菌株均以相似的方式生长，但前者去除了多达32％的镉。尽管两者的生长都随着镉浓度的升高而降低，但转基因组克隆的清除率比野生型菌株高20±9％。与野生型菌株相比，在含有2.5和10 mg / mL镉的培养基中，在质体克隆中，谷胱甘肽S-转移酶和细胞内谷胱甘肽的活性分别提高了2.1倍和1.9倍。尽管20 mg / L的镉抑制了两者的生长，但转质体克隆逐渐复制。这些结果证实了合成基因gshA的表达 如在转化菌株中的清除吸收和代谢反应增加所揭示的。