Enhancing High-Level Food-Grade Expression of Glutamate Decarboxylase and Its Application in the Production of γ-Aminobutyric Acid.

ABSTRACT: Gamma-aminobutyric acid (GABA), a non-proteinogenic amino acid, exhibits diverse physiological functions and finds extensive applications in food, medicine, and various industries. Glutamate decarboxylase (GAD) can effectively convert L-glutamic acid (L-Glu) or monosodium glutamate (MSG) into GABA. However, the low food-grade expression of GAD has hindered large-scale GABA production. In this study, we aimed to elevate GAD expression in Bacillus subtilis through cofactor synthesis enhancement, CRISPRi-based host strain modification, and fermentation optimization. In a 3-L fermenter, the optimized strain achieved a remarkable GAD activity of 319.62 U/ml without antibiotic selection pressure, representing the highest reported food-grade expression to date. Subsequently, enzymatic prop

SUBMITTER: Zhang K 

PROVIDER: S-EPMC11813360 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature