Luxuan Huang1, Lina Zhao1, Xinyi Zan1, Yuanda Song2,3, Colin Ratledge4. 1. State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, People's Republic of China. 2. State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, Jiangsu, People's Republic of China. ysong@jiangnan.edu.cn. 3. Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, 255049, Shandong, People's Republic of China. ysong@jiangnan.edu.cn. 4. School of Biological Sciences, University of Hull, Hull, HU6 7RX, UK.
Abstract
OBJECTIVES: To explore the role of thioesterases in Rhodococcus opacus PD630 by endogenously overexpression in this bacteria for increased lipid production. RESULTS: Overexpression of four thioesterases from R. opacus PD630 in E. coli led to a 2- to 8-fold increase in C16:1 and C18:1 fatty acids while, when overexpressed in R. opacus PD630, only two recombinants had significant effect on the quantities and compositions of total fatty acid. The contents of total fatty acids (FAs) in two recombinants, pJTE2 (OPAG_00508 thioesterase) and pJTE4 (WP_012687673.1 thioesterase), were 400-460 mg/g (CDW) which is 1.5 times of wild-type strain PD630 (300-350 mg/g CDW), and 20-30 % (w/w) more than that of the control strain PDpJAM2 (330-370 mg/g CDW). The contents of 17:1 and 18:1 fatty acids increased by about 27 and 35 %, respectively, in pJTE2 and by 35 and 20 %, respectively, in pJTE4 compared with the control strain. CONCLUSIONS: The engineered strains showed improved production of lipid (as total fatty acids), and could also tailor the composition of the fatty acid profile when cultured in mineral salts medium using glucose as sole carbon source.
OBJECTIVES: To explore the role of thioesterases in Rhodococcus opacus PD630 by endogenously overexpression in this bacteria for increased lipid production. RESULTS: Overexpression of four thioesterases from R. opacus PD630 in E. coli led to a 2- to 8-fold increase in C16:1 and C18:1 fatty acids while, when overexpressed in R. opacus PD630, only two recombinants had significant effect on the quantities and compositions of total fatty acid. The contents of total fatty acids (FAs) in two recombinants, pJTE2 (OPAG_00508 thioesterase) and pJTE4 (WP_012687673.1 thioesterase), were 400-460 mg/g (CDW) which is 1.5 times of wild-type strain PD630 (300-350 mg/g CDW), and 20-30 % (w/w) more than that of the control strain PDpJAM2 (330-370 mg/g CDW). The contents of 17:1 and 18:1 fatty acids increased by about 27 and 35 %, respectively, in pJTE2 and by 35 and 20 %, respectively, in pJTE4 compared with the control strain. CONCLUSIONS: The engineered strains showed improved production of lipid (as total fatty acids), and could also tailor the composition of the fatty acid profile when cultured in mineral salts medium using glucose as sole carbon source.
Entities:
Keywords:
Acyl-ACP thioesterase; E. coli; Lipid production; Rhodococcus opacus PD630; Substrate specificity; Total fatty acid