Engineering of Corynebacterium glutamicum for Consolidated Conversion of Hemicellulosic Biomass into Xylonic Acid. Issue 11 (11th September 2017)

• Record Type: Journal Article
• Authors: Yim, Sung Sun; Choi, Jae Woong; Lee, Se Hwa; Jeon, Eun Jung; Chung, Wook‐Jin; Jeong, Ki Jun
• Is Part Of: Biotechnology journal. Volume 12:Issue 11(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-09-11
• Subjects: consolidated bioprocess -- Corynebacterium glutamicum -- hemicellulose -- xylonic acid; Biotechnology -- Periodicals; 660.605
• DOI: 10.1002/biot.201700040
• Languages: English
• ISSNs: 1860-6768

Abstract

Abstract : Xylonic acid is a promising platform chemical with various applications in the fields of food, pharmaceuticals, and agriculture. However, in the current process, xylonic acid is mainly produced by the conversion of xylose, whose preparation requires substantial cost and time. Here, Corynebacterium glutamicum is engineered for the consolidated bioconversion of hemicellulosic biomass (xylan) into xylonic acid in a single cultivation. First, for the efficient conversion of xylose to xylonic acid, xylose dehydrogenase (Xdh) and xylonolactonase (XylC) from Caulobacter crescentus are evaluated together with a previously optimized xylose transporter module (XylE of Escherichia coli ), and cells expressing xdh and x ylE genes with an optimized expression system can produce xylonic acid from xylose with 100% conversion yield. Next, to directly process xylan as a substrate, an engineered xylan‐degrading module is introduced, in which two xylan‐degrading enzymes (endoxylanase and xylosidase) are secreted into the culture medium. The engineered C. glutamicum successfully produce 6.23 g L −1 of xylonic acid from 20 g L −1 of xylan. This is the first report on xylonic acid production in C. glutamicum and this robust system will contribute to development of an industrially relevant platform for production of xylonic acid from raw biomass. Abstract : Xylonic acid is a promising platform chemical with various applications. In this study, the authors engineered Corynebacterium glutamicum for the production of xylonic acid from very cheap hemicellulose biomass (xylan). This work is the potential basis for a C. glutamicum cell factory for commercial production of xylonic acid.