Crystallographic analysis of 1,2,3-trichloropropane biodegradation by the haloalkane dehalogenase DhaA31

Vapour soaking of crystals of the R. rhodochrous haloalkane dehalogenase variant DhaA31 with 1,2,3-trichloropropane at room temperature and pH 6.5 facilitated the production of a protein-substrate complex. Comparison of the substrate-free DhaA31 structure with that of the DhaA31-substrate complex revealed two alternative conformations of the nucleophilic residue Asp106 and a possible pathway for halide release, while comparison of DhaA31 with wild-type DhaA revealed reduced size and solvent-accessibility of the active site.