From the perspective of industrial integration,how the musical instruments of Li people in Hainan can solve the current development problems such as lack of endogenous power and market enthusiasm under the strategy of...From the perspective of industrial integration,how the musical instruments of Li people in Hainan can solve the current development problems such as lack of endogenous power and market enthusiasm under the strategy of rural revitalization to walk out a unique road of three-in-one industry construction was studied.展开更多
β-nicotinamide mononucleotide(β-NMN)is a bioactive nucleotide that indirectly affects various cellular metabolic pathways,and has tremendous potential in the food,pharmaceutical,and cosmetics industries.In the prese...β-nicotinamide mononucleotide(β-NMN)is a bioactive nucleotide that indirectly affects various cellular metabolic pathways,and has tremendous potential in the food,pharmaceutical,and cosmetics industries.In the present study,a multi-enzymatic cascade biocatalyst for the efficient synthesis ofβ-NMN was established.First,the optimal ribokinase gene was selected to construct a biocatalyst in a lower-endotoxin-level Escherichia coli strain to produce NMN from D-ribose.After fine-tuning the gene expression of the three cascade enzymes(RK/PRS/NAMPT),the production of NMN improved to 3.14 g/L.Next,the functions of membrane transporters that import NAM and export NMN were verified for NMN biosynthesis.Through the introduction of an ATP regeneration system,a drastic improvement in NMN biosynthesis at a yield of 8.74 g/L was achieved.The degradation of NMN and NAM in the bioconversion system was further inhibited after systematic modification of the related metabolic pathways.Finally,by incorporating two more copies of the key enzyme NAMPT and one copy of pyrophosphatase involved in inorganic pyrophosphate hydrolysis into the genome of the biocatalyst,the titer of NMN reached 12.2 g/L,with a molar conversion ratio of 98.7%from nicotinamide.This result provides an efficient and economical approach for producing NMN on an industrial scale.展开更多
基金Supported by National Innovation Planning Project for University Students in 2021 (202110414025)
文摘From the perspective of industrial integration,how the musical instruments of Li people in Hainan can solve the current development problems such as lack of endogenous power and market enthusiasm under the strategy of rural revitalization to walk out a unique road of three-in-one industry construction was studied.
基金supported by grant from the National Natural Science Foundation of China(Grant No.22377012).
文摘β-nicotinamide mononucleotide(β-NMN)is a bioactive nucleotide that indirectly affects various cellular metabolic pathways,and has tremendous potential in the food,pharmaceutical,and cosmetics industries.In the present study,a multi-enzymatic cascade biocatalyst for the efficient synthesis ofβ-NMN was established.First,the optimal ribokinase gene was selected to construct a biocatalyst in a lower-endotoxin-level Escherichia coli strain to produce NMN from D-ribose.After fine-tuning the gene expression of the three cascade enzymes(RK/PRS/NAMPT),the production of NMN improved to 3.14 g/L.Next,the functions of membrane transporters that import NAM and export NMN were verified for NMN biosynthesis.Through the introduction of an ATP regeneration system,a drastic improvement in NMN biosynthesis at a yield of 8.74 g/L was achieved.The degradation of NMN and NAM in the bioconversion system was further inhibited after systematic modification of the related metabolic pathways.Finally,by incorporating two more copies of the key enzyme NAMPT and one copy of pyrophosphatase involved in inorganic pyrophosphate hydrolysis into the genome of the biocatalyst,the titer of NMN reached 12.2 g/L,with a molar conversion ratio of 98.7%from nicotinamide.This result provides an efficient and economical approach for producing NMN on an industrial scale.
