Structural and biochemical characterization of 3-hydroxybenzoate 6-hydroxylase

The thesis deals with the characterization of a new flavoprotein hydroxylase 3 hydroxybenzoate 6-hydroxylase (3HB6H) from Rhodococcus jostii RHA1. 3HB6H is able to insert exclusively oxygen in para-position and the enzyme has been chosen to study the structural basis of such regioselectivity. As main result, functional mirror image active sites direct regioselective 3-hydroxybenzoate hydroxylation. Moreover, the nature and role of unprecedented phospholipid binding has been analyzed demonstrating a role in enzyme oligomerization and a possible protective role during catalysis. To conclude, the knowledge acquired improves our insight into the strategies of flavin-dependent regioselective hydroxylation and the results emerged in this thesis provide a foundation for further structural and kinetic studies on 3HB6H and related enzymes. &nbsp