Metabolic engineering for improved production of ethanol by Corynebacterium glutamicum.
Appl Microbiol Biotechnol
; 99(3): 1165-72, 2015 Feb.
Article
em En
| MEDLINE
| ID: mdl-25421564
ABSTRACT
Recombinant Corynebacterium glutamicum harboring genes for pyruvate decarboxylase (pdc) and alcohol dehydrogenase (adhB) can produce ethanol under oxygen deprivation. We investigated the effects of elevating the expression levels of glycolytic genes, as well as pdc and adhB, on ethanol production. Overexpression of four glycolytic genes (pgi, pfkA, gapA, and pyk) in C. glutamicum significantly increased the rate of ethanol production. Overexpression of tpi, encoding triosephosphate isomerase, further enhanced productivity. Elevated expression of pdc and adhB increased ethanol yield, but not the rate of production. Fed-batch fermentation using an optimized strain resulted in ethanol production of 119 g/L from 245 g/L glucose with a yield of 95% of the theoretical maximum. Further metabolic engineering, including integration of the genes for xylose and arabinose metabolism, enabled consumption of glucose, xylose, and arabinose, and ethanol production (83 g/L) at a yield of 90 %. This study demonstrated that C. glutamicum has significant potential for the production of cellulosic ethanol.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Corynebacterium glutamicum
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Etanol
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Engenharia Metabólica
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article