文献类型：期刊文献

英文题名：Pathway engineering in Corynebacterium glutamicum S9114 for 5-aminolevulinic acid production

作者：Zhang, Bin[1];Ye, Bang-Ce[1]

机构：[1]East China Univ Sci & Technol, Lab Biosyst & Microanal, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2018

卷号：8

期号：5

外文期刊名：3 BIOTECH

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000431720900006)】；

基金：We thank Dr. Andreas Burkovski and Dr. Xue-Lan Chen for providing pXMJ19 and pk18mobsacB. Moreover, we thank Dr. Zhong-Gui Mao and Dr. Li-Ming Liu for providing C. glutamicum S9114 strains. This study was supported by China NSF 21575089 and 21335003 and the National Key Technologies R&D Programs (2014AA021502).

语种：英文

外文关键词：Corynebacterium glutamicum; 5-Aminolevulinic acid; C5 pathway; Metabolic engineering

摘要：5-Aminolevulinic acid (ALA) is a non-protein amino acid with a significant potential for cancer treatment and plant stress resistance. Microbial fermentation has gradually replaced the traditional chemical-based method for ALA production, thus increasing the need for high-ALA-producing strains. In this study, we engineered the glutamate producing strain, Corynebacterium glutamicum S9114, for ALA production. To efficiently convert l-glutamate to ALA, hemA and hemL from Salmonella typhimurium and Escherichia coli were tandemly overexpressed. In addition, ncgl1221 encoding a glutamate transporter was deleted to block glutamate secretion and thus improve ALA production. Furthermore, the intrinsic ribosome-binding site (RBS) of hemB was replaced by a relatively weak RBS to reduce the conversion of ALA to porphyrin. Transcriptional and fermentation data confirmed that inactivation of lysE and putP reduced the conversion of glutamate to arginine and proline, which also contribute to ALA production. The final SA14 strain produced 895 mg/L concentration of ALA after 72 h incubation in a shake flask. This amount was 58-fold higher than that obtained by the parent strain C. glutamicum S9114. The results demonstrate the potential of C. glutamicum S9114 for efficient ALA production and provide new targets for the development of ALA-producing strains.