Enhancement of Xylitol Production Rate with the EMP Pathway Engineered Candida tropicalis
نویسندگان
چکیده
NADPH regeneration is a limiting factor in reduction of xylose to xylitol in C. tropicalis. The oxidative PPP is the major source of NADPH biosynthesis in yeast. To enhance metabolic flux through PPP for promotion of NADPH regeneration. Genes involoved in EMP pathway were engineered by sequencial disruption and over-expression. For this, several genes involves in EMP pathway and promoters were cloned and characterized. Xylitol production by EMP-engineered strains were evaluated using a xylitol fermentation medium with glucose as a cosubstrate. Two PFK gene encoding phosphofructokinase disrupted C. tropicalis WYPFK2, produced xylitol with a volumetric productivity of 2.25g liter h and a xylitol yield of 98%.
منابع مشابه
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