Bioconversion of p-coumaric acid to p-hydroxystyrene using phenolic acid decarboxylase from B. amyloliquefaciens in biphasic reaction system.
Phenolic acid decarboxylase (PAD) catalyzes the non-oxidative decarboxylation of p-coumaric acid (pCA) to p-hydroxystyrene (pHS). PAD from Bacillus amyloliquefaciens (BAPAD), which showed k (cat)/K (m) value for pCA (9.3 × 10³ mM⁻¹ s⁻¹), was found as the most active one using the "Subgrouping Automata" program and by comparing enzyme activity. However, the production of pHS of recombinant Escherichia coli harboring BAPAD showed only a 22.7 % conversion yield due to product inhibition. Based on the partition coefficient of pHS and biocompatibility of the cell, 1-octanol was selected for the biphasic reaction. The conversion yield increased up to 98.0 % and 0.83 g/h/g DCW productivity was achieved at 100 mM pCA using equal volume of 1-octanol as an organic solvent. In the optimized biphasic reactor, using a three volume ratio of 1-octanol to phosphate buffer phase (50 mM, pH 7.0), the recombinant E. coli produced pHS with a 88.7 % conversion yield and 1.34 g/h/g DCW productivity at 300 mM pCA.
School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
Da-Hye
DH
Jung
Wonji
W
Choi
Kwon-Young
KY
Choi
Eunok
E
Jung
Hyungdon
H
Yun
Romas J
RJ
Kazlauskas
Byung-Gee
BG
Kim
D001407:Bacillus / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055162:Biocatalysis; D001711:Biotransformation; D002262:Carboxy-Lyases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003373:Coumaric Acids / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D013343:Styrenes / Q000737:chemistry / Q000378:metabolism*
D001426:Bacterial Proteins; D003373:Coumaric Acids; D013343:Styrenes; D002262:Carboxy-Lyases; C417714:phenolic acid decarboxylase