| 초록 |
In this study, the effect of gene knock of sucA on the production of gamma-aminobutyric acid (GABA) in recombinant Escherichia coli was investigated. For this, the E. coli DGB303 mutant strain was constructed by deleting the gene of sucA, which encodes enzyme of succinyl CoA synthetase, from the chromosome of the E. coli DGB203 strain, whose GABA-producing activity was previously confirmed. From flask cultures conducted at an initial pH 7.0, it was confirmed that the mutant strain produced 1.30-fold higher GABA than the parent strain. For the development of a mass production process using the mutant, the culture was carried out in a 2.5L-fermenter. However, it was observed that the mutant grew to a high concentration but hardly produced GABA when cultured in a fermenter with pH control to 7.0. Thus, culture conditions such as pH and IPTG induction concentration and time were optimized, which resulted in a 2.17-fold increase in GABA production. |
