Production of d-xylonic acid using a non-recombinant Corynebacterium glutamicum strain. (November 2018)

• Record Type: Journal Article
• Authors: Tenhaef, Niklas; Brüsseler, Christian; Radek, Andreas; Hilmes, René; Unrean, Pornkamol; Marienhagen, Jan; Noack, Stephan
• Is Part Of: Bioresource technology. Volume 268(2018)
• Page Start: 332
• Page End: 339
• Publication Date: 2018-11
• Subjects: d-Xylonate -- Corynebacterium glutamicum -- d-Xylose -- Lignocellulosic biomass -- Sugarcane bagasse -- Sequential hydrolysis and fermentation; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2018.07.127
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: C. glutamicum Δ iolR efficiently converts d -xylose to d -xylonate. The putative myo -inositol 2-dehydrogenase IolG can catalyze oxidation of d -xylose. Fed-batch operation enables maximum product yield and high volumetric productivity. Development of a cost-efficient feedstock based on hydrolyzed sugarcane bagasse. One-pot sequential hydrolysis and fermentation process for d -xylonate production. Abstract: It was found that Corynebacterium glutamicum Δ iolR devoid of the transcriptional regulator IolR accumulates high amounts of d -xylonate when cultivated in the presence of d -xylose. Detailed analyses of constructed deletion mutants revealed that the putative myo -inositol 2-dehydrogenase IolG also acts as d -xylose dehydrogenase and is mainly responsible for d -xylonate oxidation in this organism. Process development for d -xylonate production was initiated by cultivating C. glutamicum Δ iolR on defined d -xylose/d -glucose mixtures under batch and fed-batch conditions. The resulting yield matched the theoretical maximum of 1 mol mol −1 and high volumetric productivities of up to 4 g L −1 h −1 could be achieved. Subsequently, a novel one-pot sequential hydrolysis and fermentation process based on optimized medium containing hydrolyzed sugarcane bagasse was developed. Cost-efficiency and abundance of second-generation substrates, good performance indicators, and enhanced market access using a non-recombinant strain open the perspective for a commercially viable bioprocess for d -xylonate production in the near future.