Beneficial base substitutions in Escherichia coli fucO gene for enhancement of glycolic acid production.
J Biosci Bioeng
; 138(4): 301-307, 2024 Oct.
Article
em En
| MEDLINE
| ID: mdl-39079834
ABSTRACT
Microbial production of glycolic acid (GA) from ethylene glycol is extensively used in a variety of industries because ethylene glycol is not only an inexpensive raw material but also the main component of industrial wastes. In this study, we produced GA from ethylene glycol using Escherichia coli overexpressing the endogenous 1,2-propanediol oxidoreductase (fucO) and lactaldehyde dehydrogenase (aldA) genes. To increase GA productivity, we screened a random mutant library generated using an error-prone polymerase chain reaction of fucO and obtained FucO mutants MF2-9 and MF6-9 with enhanced GA production in Lysogeny Broth medium containing 800 mM ethylene glycol. MF2-9 contained three amino acid substitutions (D23E, E222K, and G363S) and two synonymous mutations (coding DNA [c.] 93G > A and c.1131T > C) in fucO. MF6-9 contained one amino acid substitution (L377H) in FucO. An amino acid substitution (L377H) and a single synonymous mutation (c.1131T > C) in fucO contributed to the enhancement in GA production. Notably, cell lysates from E. coli harboring a synonymous mutation (c.1131T > C) or amino acid substitution (L377H) in fucO showed that only AldA activity was 1.3-fold higher than that of the cell lysate from E. coli harboring the wild-type fucO. We confirmed that c.1131T > C and L377H mutations increased aldA expression in E. coli. Analysis of mRNA levels and simulation of mRNA stabilization indicated that base substitutions at positions c.1130T, which corresponds to L377H amino acid substitution, and c.1131T increased aldA expression due to partial destabilization of the mRNA. These findings will be useful for the large-scale microbial production of GA from industrial waste.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Etilenoglicol
/
Escherichia coli
/
Glicolatos
Idioma:
En
Revista:
J Biosci Bioeng
Assunto da revista:
ENGENHARIA BIOMEDICA
/
MICROBIOLOGIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Japão
País de publicação:
Japão