Projects

Pantothenate is vitamin B5, an essential dietary vitamin for humans and animals. The biosynthetic pathway leading to pantothenate has been elucidated, and the enzymes and their corresponding genes isolated from E. coil. Since microorganisms, plants and fungi, the enzymes make pantothenates, which form pantothenate, are potentially excellent targets for the design of ant microbial 01herbicida! Agents. This project centres on the enzyme pantothenate syntheses, which catalyses the final step in the formation of pantothenate. Pantothenate syntheses are readily available throughoverexpression of the cloned gene. The recently determined crystal structure of this enzyme will bemused as a guide for both parts of this project:

(i) detailed studies of the mechanism of action Site-directed autogenesis will be used to probe the mechanistic role of key residues identified from the crystal structure, and to form stable enzyme-substrate complexes for structural studies. The substrate specificity of pantothenate syntheses will be explored and attempts made to alter the substrate specificity by autogenesis.

(ii) Design of enzyme inhibitors. Novel strategies will be used for rational inhibitor design, including Click chemistry andenzyme-templated dynamic combinatorial chemistry (DCC). Studies using Click chemistry will initially use a range of asides and alkynes based on the pastorate and adenosine, reacting via tem plating in the presence of the enzyme, and so favouring products, which bind the enzyme most tightly. Enzyme-template DCC will involve the reversible reactions of pools of molecular fragments using excess enzyme to template the formation of products, which bind tightly to the enzyme, and so are potential inhibitors. Fragments for both Click and DCC studies will be chosen using state-of-the-art techniques including in silicon molecular docking using GOLD, small molecule-protein binding by 1H NMR.

Sources: European Commission