Crystallization and preliminary X-ray diffraction analysis of domain-chimeric l-(2S3S)-butanediol dehydrogenase

摘要

A domain-chimeric l-2,3-butanediol dehydrogenase (chimera l-BDH), which was designed to possess both the S-configuration specificity of l-BDH and the stability of meso-BDH, was constructed by exchanging the respective domains of these two BDHs. However, chimera l-BDH possessed a lower enzymatic function than expected based on the two original enzymes. To elucidate the causes of the decreased stability and substrate specificity, crystallization of the protein was performed. Chimera l-BDH was purified to homogeneity via ammonium sulfate fractionation and three column-chromatography steps, and was crystallized using the hanging-drop vapour-diffusion method. The crystals belonged to space group C2221, diffracted synchrotron radiation to 1.58 Å resolution and were most likely to contain two molecules in the asymmetric unit.