Format

Send to

Choose Destination
J Microbiol Biotechnol. 2017 Oct 28;27(10):1867-1876. doi: 10.4014/jmb.1707.07046.

Effects of Increased NADPH Concentration by Metabolic Engineering of the Pentose Phosphate Pathway on Antibiotic Production and Sporulation in Streptomyces lividans TK24.

Author information

1
Department of Biological Science and Bioinformatics, Myongji University, Yongin 17058, Republic of Korea.
2
Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Taejon 34141, Republic of Korea.
3
Department of Food and Nutrition, Seoil University, Seoul 02192, Republic of Korea.

Abstract

Most of the biosynthetic pathways for secondary metabolites are influenced by carbon metabolism and supply of cytosolic NADPH. We engineered carbon distribution to the pentose phosphate pathway (PPP) and redesigned the host to produce high levels of NADPH and primary intermediates from the PPP. The main enzymes producing NADPH in the PPP, glucose 6-phosphate dehydrogenase (encoded by zwf1 and zwf2) and 6-phosphogluconate dehydrogenase (encoded by zwf3), were overexpressed with opc encoding a positive allosteric effector essential for Zwf activity in various combinations in Streptomyces lividans TK24. Most S. lividans transformants showed better cell growth and higher concentration of cytosolic NADPH than those of the control, and S. lividans TK24/pWHM3-Z23O2 containing zwf2+zwf3+opc2 showed the highest NADPH concentration but poor sporulation in R2YE medium. S. lividans TK24/pWHM3-Z23O2 in minimal medium showed the maximum growth (6.2 mg/ml) at day 4. Thereafter, a gradual decrease of biomass and a sharp increase of cytosolic NADPH and sedoheptulose 7-phosphate between days 2 and 4 and between days 1 and 3, respectively, were observed. Moreover, S. lividans TK24/pWHM3-Z23O2 produced 0.9 times less actinorhodin but 1.8 times more undecylprodigiosin than the control. These results suggested that the increased NADPH concentration and various intermediates from the PPP specifically triggered undecylprodigiosin biosynthesis that required many precursors and NADPH-dependent reduction reaction. This study is the first report on bespoke metabolic engineering of PPP routes especially suitable for producing secondary metabolites that need diverse primary precursors and NADPH, which is useful information for metabolic engineering in Streptomyces.

KEYWORDS:

6-phosphogluconate dehydrogenase; Glucose-6-phosphate dehydrogenase; Streptomyces lividans; actinorhodin; pentose phosphate pathway; undecylprodigiosin

PMID:
28838222
DOI:
10.4014/jmb.1707.07046
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for The Korean Society for Microbiology and Biotechnology.
Loading ...
Support Center