Rational reformation of Corynebacterium glutamicum for producing L-lysine by one-step fermentation from raw corn starch.
Appl Microbiol Biotechnol
; 106(1): 145-160, 2022 Jan.
Article
em En
| MEDLINE
| ID: mdl-34870736
ABSTRACT
This article focuses on engineering Corynebacterium glutamicum to produce L-lysine efficiently from starch using combined method of "classical breeding" and "genome breeding." Firstly, a thermo-tolerable L-lysine-producing C. glutamicum strain KT45-6 was obtained after multi-round of acclimatization at high temperature. Then, amylolytic enzymes were introduced into strain KT45-6, and the resultant strains could use starch for cell growth and L-lysine production except the strain with expression of isoamylase. In addition, co-expression of amylolytic enzymes showed a good performance in starch degradation, cell growth and L-lysine production, especially co-expression of α-amylase (AA) and glucoamylase (GA). Moreover, L-lysine yield was increased by introducing AA-GA fusion protein (i.e., strain KT45-6S-5), and finally reached to 23.9 ± 2.3 g/L in CgXIIIPM-medium. It is the first report of an engineered L-lysine-producing strain with maximum starch utilization that may be used as workhorse for producing amino acid using starch as the main feedstock. KEY POINTS ⢠Thermo-tolerable C. glutamicum was obtained by temperature-induced adaptive evolution. ⢠The fusion order between AA and GA affects the utilization efficiency of starch. ⢠C. glutamicum with starch utilization was constructed by optimizing amylases expression.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Corynebacterium glutamicum
Idioma:
En
Revista:
Appl Microbiol Biotechnol
Ano de publicação:
2022
Tipo de documento:
Article