These compounds will be prepared with a focus on distinct aspects of the biomolecules (first coordination sphere, different functional groups of the complex molybdopterin
ligand, hydrogen bonding sites); their stability and ability to catalyse oxygen atom transfer (in particular the oxidation of sulfite) will be assessed and their suitability to bind in the active site pocket of the protein and restore activity will be tested.
XOR is a dimeric metalloflavoprotein comprising two identical subunits of approximately 145 kDa each, including one molybdenum-containing molybdopterin
cofactor (Moco) and one flavin adenine dinucleotide (FAD) cofactor, as well as two nonidentical iron-sulfur redox centers.
Heavy metal ions inhibit molybdoenzyme activity by binding to the dithiolene moiety of molybdopterin
in Escherichia coli.
Arsenite binds to sulfhydryl groups of molybdopterin
and in doing so ultimately displaces molybdenum (Gardlik et al.
Involvement of chlA, E, M, and N loci in Escherichia coli molybdopterin
Cloning and sequencing of the Escherichia coli chlEN operon involved in molybdopterin