Establishing a novel biosynthetic pathway for the production of 3,4-dihydroxybutyric acid from xylose in Escherichia coli.
3-Hydroxy-γ-butyrolactone (3HBL) is an attractive building block owing to its broad applications in pharmaceutical industry. Currently, 3HBL is commercially produced by chemical routes using petro-derived carbohydrates, which involves hazardous materials and harsh processing conditions. Only one biosynthetic pathway has been reported for synthesis of 3HBL and its hydrolyzed form 3,4-dihydroxybutyric acid (3,4-DHBA) using glucose and glycolic acid as the substrates and coenzyme A as the activator, which involves multiple steps (>10 steps) and suffers from low productivity and yield. Here we established a novel five-step biosynthetic pathway for 3,4-DHBA generation from D-xylose based on the non-phosphorylative D-xylose metabolism, which led to efficient production of 3,4-DHBA in Escherichia coli. Pathway optimization by incorporation of efficient enzymes for each step and host strain engineering by knocking out competing pathways enabled 1.27g/L 3,4-DHBA produced in shake flasks, which is the highest titer reported so far. The novel pathway established in engineered E. coli strain demonstrates a new route for 3,4-DHBA biosynthesis from xylose, and this engineered pathway has great potential for industrial biomanufacturing of 3,4-DHBA and 3HBL.
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Jia
J
Wang
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Xiaolin
X
Shen
College of Engineering, The University of Georgia, Athens, GA 30602, USA.
Rachit
R
Jain
College of Engineering, The University of Georgia, Athens, GA 30602, USA.
Jian
J
Wang
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: yuanqp@mail.buct.edu.cn.
Qipeng
Q
Yuan
College of Engineering, The University of Georgia, Athens, GA 30602, USA. Electronic address: yajunyan@uga.edu.
Yajun
Y
Yan
D015107:4-Butyrolactone / Q000031:analogs & derivatives / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006885:Hydroxybutyrates / Q000378:metabolism*; D060847:Metabolic Engineering / Q000379:methods*; D014994:Xylose / Q000235:genetics / Q000378:metabolism
C511346:3-hydroxy-gamma-butyrolactone; D006885:Hydroxybutyrates; C041038:3,4-dihydroxybutanoic acid; D014994:Xylose; D015107:4-Butyrolactone
3; 3-hydroxy-γ-butyrolactone; 4-dihydroxybutyric acid; Escherichia coli; Metabolic engineering; Xylose metabolism