Production of fine heterologus pathways in microbial hosts is frequently hindered by insufficient knowledge of the native metabolic pathway and its cognate enzymes; often the pathway is unresolved and enzymes lack detailed characterization. An alternative paradigm to using native pathways is de novo pathway design using well-characterized, substrate-promiscuous enzymes. We demonstrate this concept using P450BM3 from Bacillus megaterium. Using a computer model, we illustrate how key P450BM3 activ site mutations enable binding of non-native substrate amorphadiene, incorporating these mutations into P450BM3 enabled the selective oxidation of amorphadiene arteminsinic-11s,12-epoxide, at titers of 250 mg L"1 in E. coli. We also demonstrate high-yeilding, selective transformations to dihydroartemisinic acid, the immediate precursor to the high value anti-malarial drug artemisinin.

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A novel semi-biosynthetic route for artemisinin production using engineered substrate-promiscuous P450BM3

Enantioselective synthesis of steroids

2′-C-Methyluridine phosphoramidite: a new building block for the preparation of RNA analogues carrying the 2′-hydroxyl group

Surgical reduction: N-Heterocyclic carbene-borane complexes such as depicted are neutral, organic soluble analogues of borohydride anions with a weak hydridic character, compatible with organometallic catalysis. They are applicable for surgical reductions in complex, multifunctional molecules. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ionic and organometallic reductions with N-heterocyclic carbene boranes.

A simple, efficient and green protocol for the regioselective and chemoselective reduction of epoxides and carbonyl compounds, with sodium borohydride in natural deep eutectic in good to excellent yields, is described.

Natural deep eutectic salt promoted regioselective reduction of epoxides and carbonyl compounds

Nucleophilic borohydride: selective reductive displacement of halides, sulfonate esters, tertiary amines, and N,N-disulfonimides with borohydride reagents in polar aprotic solvents

William Burgoyne

Papers

Nucleophilic borohydride: selective reductive displacement of halides, sulfonate esters, tertiary amines, and N,N-disulfonimides with borohydride reagents in polar aprotic solvents

Regio- and stereoselective cleavage of epoxides with cyanoborohydride and boron trifluoride etherate