We isolated and characterized D,L-halidohydrolases from five different
soil bacteria. Three of these bacterial strains bear plasmids with si
zes of approximately 60 kb. Curing and mating experiments indicated th
at these three plasmids pFL160, pFL170, and pFL190 encoded a dehalogen
ase. Owing to their biochemical characterization, these halidohydrolas
es were closely related among each other and to the DhlIV halidohydrol
ase, encoded by plasmid pFL40 from Alcaligenes xylosoxidans ssp. denit
rificans ABIV. Restriction enzyme patterns as well as DNA-hybridizatio
n experiments with an internal fragment of dhlIV revealed a high degre
e of homology among each of these four plasmids and their dehalogenase
genes.