Metabolic engineering of Bacillus amyloliquefaciens LL3 for enhanced poly-γ-glutamic acid synthesis.

ABSTRACT: Poly-γ-glutamic acid (γ-PGA) is a biocompatible and biodegradable polypeptide with wide-ranging applications in foods, cosmetics, medicine, agriculture and wastewater treatment. Bacillus amyloliquefaciens LL3 can produce γ-PGA from sucrose that can be obtained easily from sugarcane and sugar beet. In our previous work, it was found that low intracellular glutamate concentration was the limiting factor for γ-PGA production by LL3. In this study, the γ-PGA synthesis by strain LL3 was enhanced by chromosomally engineering its glutamate metabolism-relevant networks. First, the downstream metabolic pathways were partly blocked by deleting fadR, lysC, aspB, pckA, proAB, rocG and gudB. The resulting strain NK-A6 synthesized 4.84 g l^-1 γ-PGA, with a 31.5% increase compared with strain L

SUBMITTER: Gao W 

PROVIDER: S-EPMC6680638 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature