Improving ethylene glycol utilization in Escherichia coli fermentation

Engineering microbes to overproduce natural products as agrochemicals

“…Some of the potential prebiotics can be the cheap substrates such as ethylene glycol (EG), which can be obtained from plastic and cellulosic wastes [ 39 ]. Only a few Pseudomonas species such as P. putida JM37 can catabolize EG [ 39 , 40 ] . The genus Pseudomonas is one of the most significant genera of bacteria that promote plant development.…”

Current Advances in the Biodegradation and Bioconversion of Polyethylene Terephthalate

“…PET hydrolases can further hydrolyze BHET to produce MHET, TPA, and EG [12]. The products TPA and EG can be used by different microorganisms and be further metabolized into the tricarboxylic acid cycle (TCA cycle) [21][22][23][24][25][26][27][28][29]. Additionally, these intermediate and final products of PET biodegradation have been identified as competitive inhibitors of PET hydrolases [30,31] (Figure 1).…”

“…EG is assimilated and oxidized into glycolaldehyde and, subsequently, into glycolic acid under the catalysis of 1,2-propanediol oxidoreductase mutant (fucO) and glycolaldehyde dehydrogenase (aldA), respectively. Glycolic acid can be metabolized into glyoxylic acid by glycolate dehydrogenase (GlcDEF) [26]. Similar to P. putida, glyoxylic acid is further condensed into acetyl-CoA by the linear glycerate pathway or converted into isocitrate and malate catalyzed by AceA and GlcB, respectively.…”

“…Experiments identified that oxygen concentration was as an important metabolic valve, and flux to 2-phosphoglycerate was the primary route in the assimilation of EG as a substrate combining modeling [113,119]. Additionally, EG can be efficiently utilized in E. coli by optimizing the gene expression (fucO and aldA) and adding a growth medium with a low concentration of glycerol or a mixture of amino acids [26]. Although E. coli MG1655 contains the endogenous glyoxylic acid metabolism pathway, the EG-utilizing ability of the engineered E. coli still needs to be improved [119].…”

“…Two genes encoding recombinant cytosolic oxidoreductases (gox0313 and gox0646) from G. oxydans were heterologously expressed in E. coli and the resulting proteins were purified and characterized [123]. In addition to G. oxydans, engineered E. coli has potential in producing glycolic acid from EG, and 10.4 g/L of glycolic acid was produced from EG after 112 h in a fed-batch bioreactor using a series of oxygenbased strategies [26,118].…”