Bioconversion of Xylose to Ethylene Glycol and Glycolate in Engineered .

The biological production of two-carbon compounds (ethylene glycol (EG) and glycolate) has been studied for the sustainable supply of the compounds to the polymer, cosmetic, textile, and medical industries. Here, we demonstrated the bioconversion of xylose to either ethylene glycol (EG) or glycolate using engineered , a well-known industrial amino acid producer. A synthetic ribulose 1-phosphate (Ru1P) pathway involving heterologous d-tagatose 3-epimerase and l-fuculose kinase/aldolase reactions was introduced in . Subsequently, heterologous expression of YqhD reductase with the synthetic Ru1P pathway led to ethylene glycol production from xylose. Additional pathway engineering in by mutating , which encodes an aldehyde dehydrogenase, abolished the by-product formation of glycolate during xylose conversion to EG at a yield of 0.75 mol per mol. In addition, the bioconversion of xylose to glycolate was achieved, and the almost maximum molar yield was 0.99 mol per mol xylose in via the Ru1P pathway. Thus, the synthetic Ru1P pathway in led bioconversion of xylose to either ethylene glycol or glycolate with high molar yields.