Selected Mutants of Dhaa Enzyme as a Subject for Structural Studies

Structural biology is one of the most quickly growing fields of research in life sciences. X-ray diffraction analysis is the technique that allows direct visualization of protein structure at the atomic or near-atomic level. Structure solution of proteins and protein complexes by X-ray crystallography provides important insights into their mode of action. The haloalkane dehalogenase proteins represent objects of interest for protein engineering studies, attempting to improve their catalytic efficiency or broaden their substrate specificity towards environmental pollutants. In the present study, the structures of three haloalkane dehalogenase DhaA mutants DhaA04, DhaA14 and DhaA15 at atomic resolution are reported and compared to explore the effect of mutations on the enzymatic activity of modified proteins from a structural perspective. Besides that, in this work, the crystallization and initial X-ray diffraction characterization of DhaA wild type and its mutant variant DhaA13 in complex with environmental pollutant 1,2,3-trichloropropane and the crystallization of DhaA13 in complex with the fluorescence dye coumarin are described.