Efficient production of L-ribose with a recombinant Escherichia coli biocatalyst.
Appl Environ Microbiol
; 74(10): 2967-75, 2008 May.
Article
em En
| MEDLINE
| ID: mdl-18344327
ABSTRACT
A new synthetic platform with potential for the production of several rare sugars, with l-ribose as the model target, is described. The gene encoding the unique NAD-dependent mannitol-1-dehydrogenase (MDH) from Apium graveolens (garden celery) was synthetically constructed for optimal expression in Escherichia coli. This MDH enzyme catalyzes the interconversion of several polyols and their l-sugar counterparts, including the conversion of ribitol to l-ribose. Expression of recombinant MDH in the active form was successfully achieved, and one-step purification was demonstrated. Using the created recombinant E. coli strain as a whole-cell catalyst, the synthetic utility was demonstrated for production of l-ribose, and the system was improved using shaken flask experiments. It was determined that addition of 50 to 500 microM ZnCl(2) and addition of 5 g/liter glycerol both improved production. The final levels of conversion achieved were >70% at a concentration of 40 g/liter and >50% at a concentration of 100 g/liter. The best conditions determined were then scaled up to a 1-liter fermentation that resulted in 55% conversion of 100 g/liter ribitol in 72 h, for a volumetric productivity of 17.4 g liter(-1) day(-1). This system represents a significantly improved method for the large-scale production of l-ribose.
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1
Base de dados:
MEDLINE
Assunto principal:
Ribose
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Desidrogenase do Álcool de Açúcar
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Escherichia coli
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article