Title | Regulation of polyβhydroxybutyrate biosynthesis by nicotinamide nucleotide in Alcaligenes eutrophus |
Authors | In Young Lee; Mi Kyung Kim; Ho Nam Chang; Young Hoon Park |
Publisher | Wiley-Blackwell |
Issue Date | 1995 |
Citation | FEMS Microbiology Letters, vol. 131, no. 0, pp. 35-39 |
Keywords | alcaligenes eutrophus; nicotinamide nucleotide; poly-β-hydroxybutyrate biosynthesis; regulation; poly(3 hydroxybutyric acid); reduced nicotinamide adenine dinucleotide phosph; biosynthesis; genetic regulation; alcaligenes |
Abstract | Poly-β-hydroxybutyrate biosynthesis was studied in Alcaligenes eutrophus under various nutrient-limiting conditions. When the cells were cultivated in nitrogen-limited media, both the levels of NAD(P)H and the ratios of NAD(P)H/NAD(P) were higher than those under nitrogen-sufficient conditions. The specific poly-β-hydroxybutyrate production rate was found to increase with the values of both NADH/NAD and NADPH/NADP, indicating that poly-β-hydroxybutyrate synthesis is directly regulated by the ratios of nicotinamide nucleotides. The effects of nicotinamide nucleotides on poly-β-hydroxybutyrate biosynthesis was investigated with regard to enzyme kinetics. Citrate synthase activity was significantly inhibited by NADH and NADPH, indicating that poly-β-hydroxybutyrate accumulation could be enhanced by facilitating the metabolic flux of acetyl-CoA to poly-β-hydroxybutyrate synthetic pathway. It was also found that cellular NADPH was a limiting substrate for NADPH-linked reductase, controlling the overall biosynthetic activity of poly-β-hydroxybutyrate in this strain. |
ISSN | 0378-1097 |
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Registered Date |
2017-04-19 |