In:
Applied and Environmental Microbiology, American Society for Microbiology, Vol. 78, No. 8 ( 2012-04-15), p. 2596-2601
Abstract:
Corynebacterium glutamicum is widely used for industrial production of various amino acids and vitamins, and there is growing interest in engineering this bacterium for more commercial bioproducts such as γ-aminobutyric acid (GABA). In this study, a C. glutamicum GABA-specific transporter (GabP Cg ) encoded by ncgl0464 was identified and characterized. GabP Cg plays a major role in GABA uptake and is essential to C. glutamicum growing on GABA. GABA uptake by GabP Cg was weakly competed by l -Asn and l -Gln and stimulated by sodium ion (Na + ). The K m and V max values were determined to be 41.1 ± 4.5 μM and 36.8 ± 2.6 nmol min −1 (mg dry weight [DW]) −1 , respectively, at pH 6.5 and 34.2 ± 1.1 μM and 67.3 ± 1.0 nmol min −1 (mg DW) −1 , respectively, at pH 7.5. GabP Cg has 29% amino acid sequence identity to a previously and functionally identified aromatic amino acid transporter (TyrP) of Escherichia coli but low identities to the currently known GABA transporters (17% and 15% to E. coli GabP and Bacillus subtilis GabP, respectively). The mutant RES167 Δ ncgl0464 /pGXKZ9 with the GabP Cg deletion showed 12.5% higher productivity of GABA than RES167/pGXKZ9. It is concluded that GabP Cg represents a new type of GABA transporter and is potentially important for engineering GABA-producing C. glutamicum strains.
Type of Medium:
Online Resource
ISSN:
0099-2240
,
1098-5336
DOI:
10.1128/AEM.07406-11
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2012
detail.hit.zdb_id:
223011-2
detail.hit.zdb_id:
1478346-0
SSG:
12
Permalink