Clavulanic acid dehydrogenase: Structural and biochemical analysis of the final step in the biosynthesis of the β-lactamase inhibitor clavulanic acid

Abstract

The ultimate step in the biosynthesis of the medicinally important β-lactamase inhibitor clavulanic acid is catalyzed by clavulanic acid dehydrogenase (CAD). CAD is responsible for the NAPDH-dependent reduction of the unstable intermediate clavulanate-9-aldehyde to yield clavulanic acid. Here, we report biochemical and structural studies on CAD. Biophysical analyses demonstrate that CAD exists as dimeric and tetrameric species in solution. The reaction performed by CAD was shown to be reversible, allowing the use of clavulanic acid for activity analyses. The crystal structure of CAD was solved using single-wavelength anomalous diffraction with a seleno-methionine derivative. The structure re..