Engineering Gluconbacter oxydans with efficient co-utilization of glucose and sorbitol for one-step biosynthesis of 2-keto-L-gulonic.
Bioresour Technol
; 406: 131098, 2024 Aug.
Article
en En
| MEDLINE
| ID: mdl-38986886
ABSTRACT
As the highest-demand vitamin, the development of a one-step vitamin C synthesis process has been slow for a long time. In previous research, a Gluconobacter oxydans strain (GKLG9) was constructed that can directly synthesize 2-keto-L-gulonic acid (2-KLG) from glucose, but carbon source utilization remained low. Therefore, this study first identified the gene 4kas (4-keto-D-arabate synthase) to reduce the loss of extracellular carbon and inhibit the browning of fermentation broth. Then, promoter engineering was conducted to enhance the intracellular glucose transport pathway and concentrate intracellular glucose metabolism on the pentose phosphate pathway to provide more reducing power. Finally, by introducing the D-sorbitol pathway, the titer of 2-KLG was increased to 38.6 g/L within 60 h in a 5-L bioreactor, with a glucose-to-2-KLG conversion rate of about 46 %. This study is an important step in the development of single-bacterial one-step fermentation to produce 2-KLG.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sorbitol
/
Gluconobacter oxydans
/
Glucosa
Idioma:
En
Revista:
Bioresour Technol
Asunto de la revista:
ENGENHARIA BIOMEDICA
Año:
2024
Tipo del documento:
Article
Pais de publicación:
Reino Unido