Improved fermentative gamma-aminobutyric acid production from glucose by the inactivation of respiratory chain components NDH-I and Cytbo₃ in Escherichia coli.

Gamma-aminobutyric acid (GABA), which is synthesized from l-glutamic acid via glutamate decarboxylase (Gad), is used as food, supplements, and biodegradable plastics. Our previous study demonstrated an Escherichia coli mutant (ΔΔ) strain, lacking type I NADH dehydrogenase (NDH-I) and cytochrome bo oxidase (Cytbo), produced 7 g/L glutamic acid on MS1 glucose-minimal medium. In this study, the ΔΔ strain was used for improving GABA production.