Accelerated pentose utilization by Corynebacterium glutamicum for accelerated production of lysine, glutamate, ornithine and putrescine

Abstract

SummaryBecause of their abundance in hemicellulosic wastes arabinose and xylose are an interesting source of carbon for biotechnological production processes. Previous studies have engineered several Corynebacterium glutamicum strains for the utilization of arabinose and xylose, however, with inefficient xylose utilization capabilities. To improve xylose utilization, different xylose isomerase genes were tested in C. glutamicum. The gene originating from Xanthomonas campestris was shown to have the highest effect, resulting in growth rates of 0.14 h−1, followed by genes from Bacillus subtilis, Mycobacterium smegmatis and Escherichia coli. To further increase xylose utilization different xylulokinase genes were expressed combined with X. campestris xylose isomerase gene. All combinations further increased growth rates of the recombinant strains up to 0.20 h−1 and moreover increased biomass yields. The gene combination of X. campestris xylose isomerase and C. glutamicum xylulokinase was the fastest growing on xylose and compared with the previously described strain solely expressing E. coli xylose isomerase gene delivered a doubled growth rate. Productivity of the amino acids glutamate, lysine and ornithine, as well as the diamine putrescine was increased as well as final titres except for lysine where titres remained unchanged. Also productivity in medium containing rice straw hydrolysate as carbon source was increased.Funding Information No funding information provided.

Metabolic Engineering of an ATP-Neutral Embden-Meyerhof-Parnas Pathway in Corynebacterium glutamicum: Growth Restoration by an Adaptive Point Mutation in NADH Dehydrogenase

“…C. glutamicum grows aerobically on a wide variety of carbon sources, including the sugars glucose, fructose, and sucrose, as well as organic acids, such as citrate, acetate, pyruvate, D-lactate, and L-lactate. Significant efforts have been focused on engineering C. glutamicum to utilize starch (17), glucans (18), crude glycerol (19), amino sugars (20,21), and pentose sugars present in lignocellulosic hydrolysates (22), and the disaccharide cellobiose (23). However, glucose, fructose, and sucrose present in molasses or derived from starch hydrolysis are the main substrates used in industrial fermentations (24).…”

Harnessing novel chromosomal integration loci to utilize an organosolv‐derived hemicellulose fraction for isobutanol production with engineered Corynebacterium glutamicum

“…2B, C). Previous studies using plasmid‐based expression of araBAD (Schneider et al ., 2011) or xylAB (Meiswinkel et al ., 2013) yielded maximal rates of 0.31 h −1 or 0.20 h −1 respectively. In our experiments, a full consumption of the pentoses was not achieved at the end of cultivation (78 ± 7% of d ‐xylose and 14 ± 4% of l ‐arabinose metabolized).…”

“…We designed homologous flanking regions of > 500 bps to specifically locate the additional genetic information to designated CgLPs. The two synthetic operons express the xylAB genes encoding XylA (xylose isomerase) of Xanthomonas campestris and XylB (xylulokinase) of C. glutamicum and araBAD encoding AraB ( l ‐ribulokinase), AraA ( l ‐arabinose isomerase) and AraD ( l ‐ribulose‐5‐phosphate 4‐epimerase) of E. coli MG1655 under control of the constitutive promoter of the C. glutamicum elongation factor EF‐TU (cg0587, P tuf ) and are terminated by the E. coli rrnB operon terminator (T rrnB ) respectively, following already published operon architectures (Schneider et al ., 2011; Meiswinkel et al ., 2013). …”

Functional Characterization of Corynebacterium alkanolyticum β-Xylosidase and Xyloside ABC Transporter in Corynebacterium glutamicum

“…The successful expression of the xylooligosaccharide ABC transporter gene cluster in a heterologous host in this study demonstrates the central role of the cluster in uptake of arabino-xylooligosaccharides. C. glutamicum has been engineered and improved to be an effective platform for pentose fermentation (31)(32)(33), producing ethanol (34), succinic acid (35), 1,5-diaminopentane (36), and amino acids (37,38) from pentose sugars. The findings described here could offer faster, broader, and more efficient pentose sugar utilization to such potential industrial strains, and could contribute significantly to advancement of microbial lignocellulosic biomass exploitation.…”