Enhancement of l-phenylalanine production in Escherichia coli by heterologous expression of Vitreoscilla hemoglobin.
Biotechnol Appl Biochem
; 65(3): 476-483, 2018 May.
Article
em En
| MEDLINE
| ID: mdl-28872702
ABSTRACT
l-Phenylalanine is an important amino acid that is widely used in the production of food flavors and pharmaceuticals. Generally, l-phenylalanine production by engineered Escherichia coli requires a high rate of oxygen supply. However, the coexpression of Vitreoscilla hemoglobin gene (vgb), driven bya tac promoter, with the genes encoding 3-deoxy-d-arabinoheptulosonate-7-phosphate synthetase (aroF) and feedback-resistant chorismate mutase/prephenate dehydratase (pheAfbr ), led to increased productivity and decreased demand for aeration by E. coli CICC10245. Shake-flask studies showed that vgb-expressing strains displayed higher rates of oxygen uptake, and l-phenylalanine production under standard aeration conditions was increased. In the aerobic fermentation process, cell growth, l-phenylalanine production, and glucose consumption by the recombinant E. coli strain PAPV, which harbored aroF, pheAfbr , and tac-vgb genes, were increased compared to that in the strain harboring only aroF and pheAfbr (E. coli strain PAP), especially under oxygen-limited conditions. The vgb-expressing strain PAPV produced 21.9% more biomass and 16.6% more l-phenylalanine, while consuming only approximately 5% more glucose after 48 H of fermentation. This study demonstrates a method to enhance the l-phenylalanine production by E. coli using less intensive and thus more economical aeration conditions.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Contexto em Saúde:
3_ND
Problema de saúde:
3_neglected_diseases
/
3_zoonosis
Assunto principal:
Fenilalanina
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Proteínas de Bactérias
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Escherichia coli
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Hemoglobinas Truncadas
Idioma:
En
Revista:
Biotechnol Appl Biochem
Assunto da revista:
BIOQUIMICA
/
BIOTECNOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article