Metabolic engineering of 1,2-propanediol production from cellobiose using beta-glucosidase-expressing E. coli
Metabolic engineering of 1,2-propanediol production from cellobiose using beta-glucosidase-expressing E. coli
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DOI：
10.1016/j.biortech.2021.124858
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发表时间：
2021-02-22
影响因子：
11.4
通讯作者：
Kondo, Akihiko
中科院分区：
文献类型：
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作者：
Nonaka, Daisuke;Fujiwara, Ryosuke;Kondo, Akihiko
利用可再生原料微生物生产1，2-丙二醇是一种很有前途的可持续生产增值燃料和化学品的方法。我们展示了利用葡萄糖和纤维二糖提高1，2-丙二醇产量的代谢工程大肠杆菌。竞争途径的删除提高了1，2-丙二醇的产量。为了减少流向下游糖酵解的碳流，ptsG基因缺失使磷酸转移酶系统(PTS)失活。该菌株从20g/L的葡萄糖中产1，2-丙二醇1.48±0.01g/L。通过共表达β-葡萄糖苷酶(BGL)实现了糖源的调节。表达BGL的菌株在浓度为0.90±0.11g/L的条件下以纤维二糖为原料生产1，2-丙二醇，产率为0.15±0.01g/g葡萄糖(1g纤维二糖相当于1.1g葡萄糖)。以纤维二糖或低聚纤维糖为碳源，证明了利用一株表达β-葡萄糖苷酶的工程菌生产1，2-丙二醇的可行性。
Microbial 1,2-propanediol production using renewable feedstock is a promising method for the sustainable production of value-added fuels and chemicals. We demonstrated the metabolically engineered Escherichia coli for improvement of 1,2-propanediol production using glucose and cellobiose. The deletion of competing pathways improved 1,2-propanediol production. To reduce carbon flux toward downstream glycolysis, the phosphotransferase system (PTS) was inactivated by ptsG gene deletion. The resultant strain, GL3/PD, produced 1.48 ? 0.01 g/L of 1,2-propanediol from 20 g/L of glucose. A sugar supply was engineered by coexpression of ?-glucosidase (BGL). The strain expressing BGL produced 1,2-propanediol from cellobiose at a concentration of 0.90 ? 0.11 g/L with a yield of 0.15 ? 0.01 g/g glucose (cellobiose 1 g is equal to glucose 1.1 g). As cellobiose or cellooligosaccharides a carbon source, the feasibility of producing 1,2-propanediol using an E. coli strain engineered for ?-glucosidase expression are demonstrated.