A putative haloalkane dehalogenase has been identified in a marine Rhodobacteraceae and subsequently cloned and over-expressed in Escherichia coli. The enzyme has highest activity towards the substrates 1,6-dichlorohexane, 1-bromooctane, 1,3-dibromopropane and 1-bromohexane. The crystal structures of the enzyme in the native and product bound forms reveal a large hydrophobic active site cavity. A deeper substrate binding pocket defines the enzyme preference towards substrates with longer carbon chains. Arg136 at the bottom of the substrate pocket is positioned to bind the distal halogen group of extended di-halogenated substrates.
Representative scheme of Haloalkane_dehalogenase-HLD2 structure and an image from PDBsum server
Databases
PDB-Sum
4C6H Previously Class, Architecture, Topology and Homologous superfamily - PDB-Sum server
FSSP
4C6HFold classification based on Structure-Structure alignment of Proteins - FSSP server
