Construction and optimization of microbial cell factories for producing cis, cis-muconic acid

• Published in: Shengwu gongcheng xuebao Vol. 32; no. 9; p. 1212
• Main Authors: Song, Guotian, Jiang, Xiaolong, Chen, Wujiu, Peng, Yanfeng, Lu, Fuping, Wang, Qinhong
• Format: Journal Article
• Language: Chinese
• Published: China 25.09.2016
• Subjects: Escherichia coli - metabolism; Fermentation; Industrial Microbiology; Metabolic Engineering; Microorganisms, Genetically-Modified; Promoter Regions, Genetic; Sorbic Acid - analogs & derivatives; Sorbic Acid - metabolism; cis-muconic acid; constitutive promoters; Escherichia coli; high throughput screening; genome replication engineering; combinatorial regulation; cis
• ISSN: 1000-3061
• DOI: 10.13345/j.cjb.150541

cis, cis-muconic acid (MA) is an important platform chemical. Now, majority of reported engineered strains are genetically instable, the exogenous genes are expressed under the control of expensive inducer and the components of their fermentation medium are complex, thus large-scale microbial production of MA is limited due to the lack of suitable strains. Hence, it is still necessary to construct novel high-performance strain that is genetically stable, no induction and grows in simple inorganic fermentation medium. In this study, after 3 exogenous genes (aroZ, aroY, catA) for biosynthesis of MA were integrated into previously constructed 3-hydroshikimate producing Escherichia coli WJ060 strain and combinatorially regulated with 3 constitutive promoters with different strengths, 27 engineered strains were constructed. The best engineered strain, E. coli MA30 could produce 1.7 g/L MA in the simple inorganic fermentation medium without induction. To further enhance the production capacity of MA, the mutant lib