원문정보
초록
영어
3-Hydroxypropionic acid (3-HP) is an important platform chemical having diverse industrial applications, but its biological production has not been well studied. We have developed various recombinant Escherichia coli biocatalysts for the production of 3-HP from glycerol, and demonstrated that the strain E. coli SH254, expressing glycerol dehydratase (dhaB1, dhaB2, and dhaB3) and aldehyde dehydrogenase (aldH), could effectively produce 3-HP at 6.5 mmol 1 . The recombinant E. coli SH254 strain was further improved by changing the expression vectors for glycerol dehydratase and aldehyde dehydrogenase and cloning the additional genes (gdrAB) which encode dehydratase reactivase. The resultant recombinant SH-BGA1 exhibited improved activities of the two relevant enzymes in vivo and a higher 3-HP titer of 51 mmol 3-HP 1 in
shake-flask conditions. When a pH-stat, fed-batch culture was conducted in 5-L bioreactor, the recombinant E. coli SH-BGA1 produced 3-HP at 346±20 mmol or 31±1.8g 3-HP per liter in 72h. The final yield of 3-HP was 0.35 mol mol glycerol. The maximum specific rate of 3-HP production was estimated at 1.43 mmol g cdw h between 8 and 72 h. Here, for the first time, we report the high titer of 3-HP production using the recombinant E.coli SH-BGA1.