Increasing l-isoleucine production in Corynebacterium glutamicum by overexpressing global regulator Lrp and two-component export system BrnFE
Article first published online: 8 FEB 2013
© 2013 The Society for Applied Microbiology
Journal of Applied Microbiology
Volume 114, Issue 5, pages 1369–1377, May 2013
How to Cite
Yin, L., Shi, F., Hu, X., Chen, C. and Wang, X. (2013), Increasing l-isoleucine production in Corynebacterium glutamicum by overexpressing global regulator Lrp and two-component export system BrnFE. Journal of Applied Microbiology, 114: 1369–1377. doi: 10.1111/jam.12141
- Issue published online: 15 APR 2013
- Article first published online: 8 FEB 2013
- Accepted manuscript online: 20 JAN 2013 03:55AM EST
- Manuscript Accepted: 11 JAN 2013
- Manuscript Revised: 30 DEC 2012
- Manuscript Received: 6 SEP 2012
- National key Basic Research Program of China. Grant Number: 2012CB725202
- the Basic Research Programs of Jiangsu Province. Grant Number: BK2009003
- 111 Project. Grant Number: No. 111-2-06
- Corynebacterium glutamicum ;
- l-isoleucine production;
To increase the l-isoleucine production in Corynebacterium glutamicum by overexpressing the global regulator Lrp and the two-component export system BrnFE.
Methods and Results
The brnFE operon and the lrp gene were cloned into the shuttle vector pDXW-8 individually or in combination. The constructed plasmids were transformed into an l-isoleucine-producing strain C. glutamicum JHI3-156, and the l-isoleucine production in these different strains was analysed and compared. More l-isoleucine was produced when only Lrp was expressed than when only BrnFE was expressed. Significant increase in l-isoleucine production was observed when Lrp and BrnFE were expressed in combination. Compared to the control strain, l-isoleucine production in JHI3-156/pDXW-8-lrp-brnFE increased 63% in flask cultivation, and the specific yield of l-isoleucine increased 72% in fed-batch fermentation.
Both Lrp and BrnFE are important to enhance the l-isoleucine production in C. glutamicum.
Significance and Impact of the Study
The results provide useful information to enhance l-isoleucine or other branched-chain amino acid production in C. glutamicum.