TY - JOUR
T1 - Production of p-hydroxybenzoic acid from p-coumaric acid by Burkholderia glumae BGR1
AU - Jung, Da Hye
AU - Kim, Eun Jung
AU - Jung, Eunok
AU - Kazlauskas, Romas J.
AU - Choi, Kwon Young
AU - Kim, Byung Gee
N1 - Publisher Copyright:
© 2015 Wiley Periodicals, Inc.
PY - 2016/7/1
Y1 - 2016/7/1
N2 - p-Coumaric acid (pCA) is abundant in biomass with low lignin content, such as straw and stubble from rye, wheat, and barley. pCA can be isolated from biomass and used for the synthesis of aromatic hydrocarbons. Here, we report engineering of the natural pathway for conversion of pCA into p-hydroxybenzoic acid (pHBA) to increase the amount of pHBA that accumulates more than 100-fold. Burkholderia glumae strain BGR1 (BGR1) grows efficiently on pCA as a sole carbon source via a CoA-dependent non-β-oxidation pathway. This pathway removes two carbons from pCA as acetyl-CoA yielding p-hydroxybenzaldehyde and subsequently oxidizes it to pHBA. To increase the amount of accumulated pHBA in BGR1, we first deleted two genes encoding enzymes that degrade pHBA in the β-ketoadipate pathway. At 10mM of pCA, the double deletion mutant BGR1_PB4 (Δphb3hΔbcl) accumulated pHBA with 95% conversion, while the control BGR1 accumulated only with 11.2% conversion. When a packed bed reactor containing immobilized BGR1_PB4 cells was operated at a dilution rate 0.2h-1, the productivity of pHBA was achieved at 9.27mg/L/h for 134h. However, in a batch reactor at 20mM pCA, growth of BGR1_PB4 was strongly inhibited, resulting in a low conversion of 19.3%. To further increase the amount of accumulated pCA, we identified the first enzyme in the pathway, p-hydroxcinnmaoyl-CoA synthetase II (phcs II), as the rate-limiting enzyme. Over expression of phcs II using a Palk promoter in a batch reaction at 20mM of pCA yielded 99.0% conversion to pHBA, which is the highest concentration of pHBA ever reported using a biological process.
AB - p-Coumaric acid (pCA) is abundant in biomass with low lignin content, such as straw and stubble from rye, wheat, and barley. pCA can be isolated from biomass and used for the synthesis of aromatic hydrocarbons. Here, we report engineering of the natural pathway for conversion of pCA into p-hydroxybenzoic acid (pHBA) to increase the amount of pHBA that accumulates more than 100-fold. Burkholderia glumae strain BGR1 (BGR1) grows efficiently on pCA as a sole carbon source via a CoA-dependent non-β-oxidation pathway. This pathway removes two carbons from pCA as acetyl-CoA yielding p-hydroxybenzaldehyde and subsequently oxidizes it to pHBA. To increase the amount of accumulated pHBA in BGR1, we first deleted two genes encoding enzymes that degrade pHBA in the β-ketoadipate pathway. At 10mM of pCA, the double deletion mutant BGR1_PB4 (Δphb3hΔbcl) accumulated pHBA with 95% conversion, while the control BGR1 accumulated only with 11.2% conversion. When a packed bed reactor containing immobilized BGR1_PB4 cells was operated at a dilution rate 0.2h-1, the productivity of pHBA was achieved at 9.27mg/L/h for 134h. However, in a batch reactor at 20mM pCA, growth of BGR1_PB4 was strongly inhibited, resulting in a low conversion of 19.3%. To further increase the amount of accumulated pCA, we identified the first enzyme in the pathway, p-hydroxcinnmaoyl-CoA synthetase II (phcs II), as the rate-limiting enzyme. Over expression of phcs II using a Palk promoter in a batch reaction at 20mM of pCA yielded 99.0% conversion to pHBA, which is the highest concentration of pHBA ever reported using a biological process.
KW - Burkholderia glumae BGR1
KW - p-coumaric acid
KW - p-hydroxybenzoic acid
UR - http://www.scopus.com/inward/record.url?scp=84953328693&partnerID=8YFLogxK
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U2 - 10.1002/bit.25908
DO - 10.1002/bit.25908
M3 - Article
C2 - 26693833
AN - SCOPUS:84953328693
SN - 0006-3592
VL - 113
SP - 1493
EP - 1503
JO - Biotechnology and bioengineering
JF - Biotechnology and bioengineering
IS - 7
ER -