Structure of Anticancer Ruthenium Half-Sandwich Complex Bound to Glycogen Synthase Kinase 3ß
G. Atilla-Gocumen, L. Di Costanzo, E. Meggers [1]
Molecular Tour
A crystal structure of an bound to the protein kinase glycogen synthase kinase 3ß (GSK-3ß) has been determined and reveals that the inhibitor binds to the via an induced fit mechanism utlizing several and . Importantly, the metal is not involved in any direct interaction with the protein kinase but fulfills a purely structural role. The unique, bulky molecular structure of the half-sandwich complex with the CO-ligand oriented perpendicular to the pyridocarbazole heterocycle allows the complex to stretch the whole distance and to interact tightly with . Although this complex is a conventional ATP-competitive binder, the unique shape of the complex allows novel interactions with the glycine-rich loop which are crucial for binding potency and selectivity. It can be hypothesized that coordination spheres which present other ligands towards the glycine-rich loop might display completely different protein kinase selectivities.
