Engineered biosynthesis biosynthetic pathway

The extraction of diterpenoids from plants has been tedious and inefficient and requires substantial sacrifice of natural resources. Tanshinones show a broad spectrum of activities the studies on biosynthesis of tanshinones are helpful to understand the biosynthetic pathway and the relationship between the properties of their scaffold and activities and produce new active analogs via genetic engineering. The biosynthetic pathways of the tanshinones have been explored for more than two decades, and work is still ongoing to determine the exact transformations and related enzymes. 

Figure 11.3 Principle of combinatorial biosynthesis. Genetic engineering and recombination of the biosynthetic pathways are two major strategies in combinatorial biosynthesis to expand structural diversity...

Motivated by the value of these natural products, there has been much research focused on developing guidelines for engineering polyketide synthases to generate natural and novel polyketides [445,446], Additionally, manipulation of the biosynthetic pathways of microbial polyketides through engineering permits the biosynthesis of bioactive polyketides not generated naturally [447,448],... 

Yamase H, Zhao L, Liu H-W (2000) Engineering a hybrid sugar biosynthetic pathway production of L-rhamnose and its implication on dihydrostreptose biosynthesis. J Am Chem Soc 122 12397-12398... 

L-Threonine is one of the three major amino acids produced by fermentation processes [45]. Currently, more than 4,000 tons of L-threonine are produced annually by fermentation [46]. In this section, we examine the L-threonine biosynthetic pathway and its regulation, and discuss how the carbon flux can be maximized towards L-threonine biosynthesis by metabolic engineering. The detailed description on L-threonine biosynthetic pathways and regulations involved is shown in Fig. 1. 

Marasco, E.K. and Schmidt-Dannert, C. (2007) Biosynthesis of plant natural products and characterization of plant biosynthetic pathways in recombinant microorganisms, in Applications of Plant Metabolic Engineering (eds R. Verpoorte, A.W. Alfer-mann and T.S. Johnson). Springer, Heidelberg, pp. 1-43. 

---