BioChem - DOS

Enhanced production of gamma-aminobutyrate (GABA) in recombinant Corynebacterium glutamicum strains from empty fruit bunch biosugar solution

Microbial cell factories

Baritugo, Kei-Anne; Kim, Hee Taek; David, Yokimiko; Khang, Tae Uk; Hyun, Sung Min; Kang, Kyoung Hee; Yu, Ju Hyun; Choi, Jong Hyun; Song, Jae Jun; Joo, Jeong Chan; Park, Si Jae

<P><B>Background</B></P><P>Recent interest has been focused on the production of platform chemicals from renewable biomass due to increasing concerns on global warming and depletion of fossil fuel reserves. Microbial production of platform chemicals in biorefineries has been suggested to be a promising solution for these problems. Gamma-aminobutyrate (GABA), a versatile bulk chemical used in food and pharmaceutical industry, is also used as a key monomer for nylon 4. GABA can be biologically produced by decarboxylation of glutamate.</P><P><B>Results</B></P><P>In this study, we examined high glutamate-producing <I>Corynebacterium glutamicum</I> strains as hosts for enhanced production of GABA from glucose and xylose as carbon sources. An <I>Escherichia coli gadB</I> mutant with a broad pH range of activity and <I>E. coli xylAB</I> genes were expressed under the control of a synthetic H36 promoter. When empty fruit bunch (EFB) solution was used as carbon source (45&nbsp;g/L glucose and 5&nbsp;g/L xylose), 12.54 ± 0.07&nbsp;g/L GABA was produced by recombinant <I>C. glutamicum</I> H36GD1852 expressing <I>E. coli gadB mutant&nbsp;gene</I> and <I>xylAB</I> genes. Batch fermentation of the same strain resulted in the production of 35.47&nbsp;g/L of GABA when EFB solution was added to support 90&nbsp;g/L glucose and 10&nbsp;g/L xylose.</P><P><B>Conclusions</B></P><P>This is the first report of GABA production by recombinant <I>C. glutamicum</I> strains from co-utilization of glucose and xylose from EFB solution. Recombinant <I>C. glutamicum</I> strains developed in this study should be useful for an efficient and sustainable production of GABA from lignocellulosic biomasses.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (10.1186/s12934-018-0977-9) contains supplementary material, which is available to authorized users.</P>

2018

BioMed Central

cc-by

1475-2859

17

pp.129

10.1186/s12934-018-0977-9

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART90638172

https://microbialcellfactories.biomedcentral.com/track/pdf/10.1186/s12934-018-0977-9

Corynebacterium glutamicum; Co-utilization; Xylose; Gamma-aminobutyrate; Empty fruit bunch