Triptolide has wide clinical applications due to its anti-inflammatory, anti-tumor and immunosuppressive activities. In this study, we investigated the effect of blocking isopentenyl pyrophosphate (IPP) translocation on the biosynthesis of triptolide by exogenously adding D,L-glyceraldehyde (DLG) to the suspension cells of Ttripterygium wilfordii at different stages (7 d, 14 d). Subsequently, the cell viability, biomass accumulation, triptolide contents, as well as the profiles of the key enzyme genes involved in the upstream pathway of triptolide biosynthesis, were analyzed. The results showed that IPP translocation is involved in the biosynthesis of triptolide. IPP is mainly translocated from the plastid (containing the MEP pathway) to the cytoplasm (containing the MVA pathway) in the early stage of the culture, but reversed in the late stage. Blocking the translocation of IPP affected the expression of key enzyme genes involved in the upstream pathway of triptolide, which in turn affected the accumulation of triptolide. Understanding the characteristics and mechanism of IPP translocation provides a theoretical basis for further promoting triptolide biosynthesis through synthetic biology.
Diterpenes ; Epoxy Compounds ; Hemiterpenes ; Organophosphorus Compounds ; Phenanthrenes

As an important industrial chemical, isoprene is mainly used as a precursor for synthetic rubbers. In addition, it also has wide applications in the field of pharmaceutical and chemical intermediates, food, adhesives and aviation fuel. Compared with conventional petrochemical routes, production of isoprene in microbial systems has been the research focus considering environment friendly and sustainable development features. This article summarizes the metabolic pathways and key enzymes of isoprene biosynthesis, reviews current methods and strategies in improving isoprene production of Escherichia coli, and also gives some basic ideas and expectation.
Butadienes ; Escherichia coli ; Hemiterpenes ; biosynthesis ; Industrial Microbiology ; Metabolic Engineering ; Metabolic Networks and Pathways ; Pentanes

Linalool is an important monoterpene, and widely used in food, pharmaceutical and cosmetic industry. The low concentration in plants and the difficulties in extraction restrict its large scale production. Saccharomyces cerevisiae can provide the monoterpene precursor, geranyl diphosphate (GPP) through its endogenous isoprenoid pathway. Therefore, it could be used as the host for monoterpene production. However, the weak metabolic flux through the isoprenoid pathway leads to the insufficient supply of GPP, and results in low monoterpene productivity. In order to increase the metabolic flux, we constructed the integrated expression plasmid pRS305-tHMG1 and free expression plasmid pYLIS-IDI1 to enhance the expression levels of isopentenyl diphosphate isomerase (IDI1) and a truncated 3-hydroxyl-3-methylglutaryl-CoA reductase gene (tHMG1). The two plasmids were separately transformed into S. cerevisiae CEN.PK2-1C, resulting in strains LS01 and LS02. The plasmid pYLIS-IDI1 was further transformed into strain LS01, resulting in strain LS03. GC-MS analysis showed that the linalool concentration was increased by 1.3 times and reached (127.71 +/- 7.68) microg/L. In conclusion, enhancement of the supply of GPP precursors through the regulation of isoprenoid pathway could increase the linalool production in S. cerevisiae.
Biosynthetic Pathways ; genetics ; Butadienes ; metabolism ; Hemiterpenes ; metabolism ; Monoterpenes ; metabolism ; Pentanes ; metabolism ; Saccharomyces cerevisiae ; genetics ; metabolism

Isoprene is an important precursor of synthetic rubber material. In our previous study, metabolic engineered Escherichia coli strain (BW-01) was constructed and used to produce isoprene. Based on the theory of protein budget, using synthetic biology strategies including the increased copy number of genes and rare codons, we regulated the expression of key enzyme to improve isoprene production in Escherichia coli strain. Under shake-flask conditions, isoprene productivity of the engineered strain (BW-07) increased by 73% compared with BW-01, reached 761.1 mg/L. It provides a reference for further studies.
Butadienes ; Escherichia coli ; genetics ; metabolism ; Gene Dosage ; Hemiterpenes ; biosynthesis ; Industrial Microbiology ; Metabolic Engineering ; Mevalonic Acid ; Pentanes ; Synthetic Biology

The world's energy and global warming crises call for sustainable, renewable, carbon-neutral alternatives to replace fossil fuel resources. Currently, most biofuels are produced from agricultural crops and residues, which lead to concerns about food security and land shortage. Compared to the current biofuel production system, cyanobacteria, as autotrophic prokaryotes, do not require arable land and can grow to high densities by efficiently using solar energy, CO(2), water, and inorganic nutrients. Moreover, powerful genetic techniques of cyanobacteria have been developed. For these reasons, cyanobacteria, which carry out oxygenic photosynthesis, are attractive hosts for production of fuels and chemicals. Recently, several chemicals including ethanol, isobutanol and isoprene have been produced by engineered cyanobacteria directly using solar energy, CO(2), and water. Cyanobacterium is therefore a potential novel cell factory for fuels and chemicals production to address global energy security and climate change issues.
Biofuels ; Butadienes ; Butanols ; metabolism ; Carbon Dioxide ; metabolism ; Cyanobacteria ; genetics ; growth & development ; metabolism ; radiation effects ; Ethanol ; metabolism ; Genetic Engineering ; methods ; Hemiterpenes ; biosynthesis ; Pentanes ; Photosynthesis ; Sunlight ; Water ; metabolism