Dataset Information

Overexpression of mGDH in Gluconobacter oxydans to improve D-xylonic acid production from corn stover hydrolysate.

ABSTRACT:

Background

D-Xylonic acid is a versatile platform chemical with broad potential applications as a water reducer and disperser for cement and as a precursor for 1,4-butanediol and 1,2,4-tributantriol. Microbial production of D-xylonic acid with bacteria such as Gluconobacter oxydans from inexpensive lignocellulosic feedstock is generally regarded as one of the most promising and cost-effective methods for industrial production. However, high substrate concentrations and hydrolysate inhibitors reduce xylonic acid productivity.

Results

The D-xylonic acid productivity of G. oxydans DSM2003 was improved by overexpressing the mGDH gene, which encodes membrane-bound glucose dehydrogenase. Using the mutated plasmids based on pBBR1MCS-5 in our previous work, the recombinant strain G. oxydans/pBBR-R3510-mGDH was obtained with a significant improvement in D-xylonic acid production and a strengthened tolerance to hydrolysate inhibitors. The fed-batch biotransformation of D-xylose by this recombinant strain reached a high titer (588.7 g/L), yield (99.4%), and volumetric productivity (8.66 g/L/h). Moreover, up to 246.4 g/L D-xylonic acid was produced directly from corn stover hydrolysate without detoxification at a yield of 98.9% and volumetric productivity of 11.2 g/L/h. In addition, G. oxydans/pBBR-R3510-mGDH exhibited a strong tolerance to typical inhibitors, i.e., formic acid, furfural, and 5-hydroxymethylfurfural.

Conclusion

Through overexpressing mgdh in G. oxydans, we obtained the recombinant strain G. oxydans/pBBR-R3510-mGDH, and it was capable of efficiently producing xylonic acid from corn stover hydrolysate under high inhibitor concentrations. The high D-xylonic acid productivity of G. oxydans/pBBR-R3510-mGDH made it an attractive choice for biotechnological production.

SUBMITTER: Mao X

PROVIDER: S-EPMC8905809 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Publications

Overexpression of mGDH in Gluconobacter oxydans to improve D-xylonic acid production from corn stover hydrolysate.

Mao Xinlei X Zhang Baoqi B Zhao Chenxiu C Lin Jinping J Wei Dongzhi D

Microbial cell factories 20220309 1

<h4>Background</h4>D-Xylonic acid is a versatile platform chemical with broad potential applications as a water reducer and disperser for cement and as a precursor for 1,4-butanediol and 1,2,4-tributantriol. Microbial production of D-xylonic acid with bacteria such as Gluconobacter oxydans from inexpensive lignocellulosic feedstock is generally regarded as one of the most promising and cost-effective methods for industrial production. However, high substrate concentrations and hydrolysate inhibi ...[more]

PMID: 35264166

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Dataset Information

Overexpression of mGDH in Gluconobacter oxydans to improve D-xylonic acid production from corn stover hydrolysate.

Background

Results

Conclusion

Publications

Overexpression of mGDH in Gluconobacter oxydans to improve D-xylonic acid production from corn stover hydrolysate.

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