Development and evaluation of efficient recombinant Escherichia coli strains for the production of 3-hydroxypropionic acid from glycerol.
3-Hydroxypropionic acid (3-HP) is a commercially valuable chemical with the potential to be a key building block for deriving many industrially important chemicals. However, its biological production has not been well documented. Our previous study demonstrated the feasibility of producing 3-HP from glycerol using the recombinant Escherichia coli SH254 expressing glycerol dehydratase (DhaB) and aldehyde dehydrogenase (AldH), and reported that an "imbalance between the two enzymes" and the "instability of the first enzyme DhaB" were the major factors limiting 3-HP production. In this study, the efficiency of the recombinant strain(s) was improved by expressing DhaB and AldH in two compatible isopropyl-thio-beta-galactoside (IPTG) inducible plasmids along with glycerol dehydratase reactivase (GDR). The expression levels of the two proteins were measured. It was found that the changes in protein expression were associated with their enzymatic activity and balance. While cloning an alternate aldehyde dehydrogenase (ALDH), alpha-ketoglutaric semialdehyde dehydrogenase (KGSADH), instead of AldH, the recombinant E. coli SH-BGK1 showed the highest level of 3-HP production (2.8 g/L) under shake-flask conditions. When an aerobic fed-batch process was carried out under bioreactor conditions at pH 7.0, the recombinant SH-BGK1 produced 38.7 g 3-HP/L with an average yield of 35%. This article reports the highest level of 3-HP production from glycerol thus far.
Rathnasingh
Chelladurai
C
Department of Chemical and Biochemical Engineering, Pusan National University, Busan 609-735, Republic of Korea.
Raj
Subramanian Mohan
SM
Jo
Ji-Eun
JE
Park
Sunghoon
S
D000444:Aldehyde Dehydrogenase / Q000235:genetics / Q000378:metabolism; D053898:Biosynthetic Pathways / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D015964:Gene Expression Regulation, Bacterial; D005818:Genetic Engineering; D005990:Glycerol / Q000378:metabolism*; D006836:Hydro-Lyases / Q000235:genetics / Q000378:metabolism; D019344:Lactic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis; D010957:Plasmids; D011401:Promoter Regions, Genetic; D011995:Recombination, Genetic
D029968:Escherichia coli Proteins; D019344:Lactic Acid; C031601:hydracrylic acid; D000444:Aldehyde Dehydrogenase; D006836:Hydro-Lyases; C020671:glycerol dehydratase; D005990:Glycerol