In:
Biotechnology and Applied Biochemistry, Wiley, Vol. 63, No. 6 ( 2016-11), p. 877-885
Abstract:
Three genes, gnd , pgl , and fbp , relevant to the pentose phosphate pathway (PPP) were overexpressed in Corynebacterium glutamicum IWJ001, leading to increase of l‐isoleucine production. The transcriptional levels of gnd , pgl , and fbp significantly increased in IWJ001/pDXW‐8‐ gnd ‐ fbp ‐ pgl . Compared with the control strain IWJ001/pDXW‐8, intracellular NADPH/NADP + ratios in IWJ001/pDXW‐8‐ gnd and IWJ001/pDXW‐8‐ gnd ‐ fbp cells grown for 36 H increased threefold and fourfold, respectively, indicating that overexpression of gnd and fbp redirected the carbon flux to PPP. Intracellular NADPH/NADP + ratio in IWJ001/pDXW‐8‐ gnd ‐ fbp ‐ pgl grown for 36 H was similar to IWJ001/pDXW‐8, suggesting that the NADPH produced by PPP could be quickly consumed for l‐isoleucine production. 10.9 and 28.96 g/L of l‐isoleucine was produced in IWJ001/pDXW‐8‐ gnd ‐ fbp ‐ pgl in shake flask cultivation and fed‐batch fermentation, respectively. In addition, IWJ001/pDXW‐8‐ gnd ‐ fbp ‐ pgl grew fast, its dry cell weight reached 49 g/L after 48 H, whereas the start strain IWJ001/pDXW‐8 reached only 40 g/L. After 96 H fermentation, l‐isoleucine yield on glucose in IWJ001/pDXW‐8‐ gnd ‐ fbp ‐ pgl reached 0.138 g/g. The results demonstrate that carbon flux redirection to PPP is an efficient approach to enhance l‐isoleucine production in C. glutamicum .
Type of Medium:
Online Resource
ISSN:
0885-4513
,
1470-8744
DOI:
10.1002/bab.2016.63.issue-6
Language:
English
Publisher:
Wiley
Publication Date:
2016
detail.hit.zdb_id:
1496341-3
SSG:
12
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