Effect of process parameters on 3-hydroxypropionic acid production from glycerol using a recombinant Escherichia coli.
The top-valued platform chemical, 3-hydroxypropionic acid (3-HP), has a wide range of industrial applications but its biological production is not well established. Previously, the production of 3-HP from glycerol was demonstrated using a recombinant Escherichia coli strain expressing glycerol dehydratase (dhaB) and aldehyde dehydrogenase (aldH). The present investigation focuses on the effect of the culture conditions on the production of 3-HP from glycerol. The physicochemical parameters, such as pH, IPTG concentration, liquid-to-flask volume ratio, and substrate concentration, were examined in flask-scale experiments and obtained the highest titer of 3-HP at 4.4 g l(-1) in 48 h. When a fed-batch process was carried out in a bioreactor under pH-regulated conditions, the recombinant E. coli produced 3-HP at 31 g l(-1) in 72 h with a yield of 0.35 mol mol(-1) glycerol. The maximum specific rate of 3-HP production was estimated to be 3.41 mmol g(-1) cdw h(-1) between 12 and 24 h. Other than 3-HP, propionic acid (3.4 g l(-1)), 1,3-propanediol (2.4 g l(-1)), and lactic acid (1.6 g l(-1)) were produced as the major by-products. This paper reports for the first time a commercially meaningful high titer of 3-HP production.
Mohan Raj
Subramanian
S
Department of Chemical and Biochemical Engineering, Pusan National University, Busan, 609-735, Republic of Korea.
Rathnasingh
Chelladurai
C
Jung
Woo-Chel
WC
Park
Sunghoon
S
D000444:Aldehyde Dehydrogenase / Q000235:genetics; D003470:Culture Media / Q000737:chemistry; D004926:Escherichia coli / Q000254:growth & development* / Q000378:metabolism*; D015870:Gene Expression; D005990:Glycerol / Q000378:metabolism*; D006836:Hydro-Lyases / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D007544:Isopropyl Thiogalactoside / Q000378:metabolism; D019344:Lactic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D011409:Propylene Glycols / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics
D003470:Culture Media; D011409:Propylene Glycols; D011994:Recombinant Proteins; D019344:Lactic Acid; D007544:Isopropyl Thiogalactoside; C041787:1,3-propanediol; C031601:hydracrylic acid; D000444:Aldehyde Dehydrogenase; D006836:Hydro-Lyases; C020671:glycerol dehydratase; D005990:Glycerol