fulltext.study @t Gmail

Enhanced xylitol production through simultaneous co-utilization of cellobiose and xylose by engineered Saccharomyces cerevisiae

Paper ID Volume ID Publish Year Pages File Format Full-Text
31666 44827 2013 9 PDF Available
Title
Enhanced xylitol production through simultaneous co-utilization of cellobiose and xylose by engineered Saccharomyces cerevisiae
Abstract

As Saccharomyces cerevisiae cannot utilize xylose as a carbon source, expression of XYL1 coding for xylose reductase (XR) from Scheffersomyces (Pichia) stipitis enabled production of xylitol from xylose with a high yield. However, insufficient supply of NAD(P)H for XR and inhibition of xylose uptake by glucose are identified as major constraints for achieving high xylitol productivity. To overcome these problems, we engineered S. cerevisiae capable of converting xylose into xylitol through simultaneous utilization of xylose and cellobiose. An engineered S. cerevisiae (D-10-BT) expressing XR, cellodextrin transporter (cdt-1) and intracellular β-glucosidase (gh1-1) produced xylitol via simultaneous utilization of cellobiose and xylose. The D-10-BT strain exhibited 40% higher volumetric xylitol productivity with co-consumption of cellobiose and xylose compared to sequential utilization of glucose and xylose. Furthermore, the overexpression of S. cerevisiae ALD6, IDP2, or S. stipitis ZWF1 coding for cytosolic NADP+-dependent dehydrogenases increased the intracellular NADPH availability of the D-10-BT strain, which resulted in a 37–63% improvement in xylitol productivity when cellobiose and xylose were co-consumed. These results suggest that co-utilization of cellobiose and xylose can lead to improved xylitol production through enhanced xylose uptake and efficient cofactor regeneration.

► Co-utilization of cellobiose and xylose was able to support enhanced xylitol production. ► The co-fermenting strain showed higher xylitol productivity compared to sequential utilization. ► Overexpression of NADPH producing enzymes facilitated improved xylitol production. ► Economic production of xylitol from cellulosic hydrolysates will be feasible.

Keywords
Xylitol; Co-utilization; Cellobiose; Cellodextrin transporter; Cofactor regeneration
First Page Preview
Enhanced xylitol production through simultaneous co-utilization of cellobiose and xylose by engineered Saccharomyces cerevisiae
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Metabolic Engineering - Volume 15, January 2013, Pages 226–234
Authors
, , , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us