Degradation of 1,3-dichloropropene by pseudomonas cichorii 170.
The gram-negative bacterium Pseudomonas cichorii 170, isolated from soil that was repeatedly treated with the nematocide 1, 3-dichloropropene, could utilize low concentrations of 1, 3-dichloropropene as a sole carbon and energy source. Strain 170 was also able to grow on 3-chloroallyl alcohol, 3-chloroacrylic acid, and several 1-halo-n-alkanes. This organism produced at least three different dehalogenases: a hydrolytic haloalkane dehalogenase specific for haloalkanes and two 3-chloroacrylic acid dehalogenases, one specific for cis-3-chloroacrylic acid and the other specific for trans-3-chloroacrylic acid. The haloalkane dehalogenase and the trans-3-chloroacrylic acid dehalogenase were expressed constitutively, whereas the cis-3-chloroacrylic acid dehalogenase was inducible. The presence of these enzymes indicates that 1, 3-dichloropropene is hydrolyzed to 3-chloroallyl alcohol, which is oxidized in two steps to 3-chloroacrylic acid. The latter compound is then dehalogenated, probably forming malonic acid semialdehyde. The haloalkane dehalogenase gene, which is involved in the conversion of 1,3-dichloropropene to 3-chloroallyl alcohol, was cloned and sequenced, and this gene turned out to be identical to the previously studied dhaA gene of the gram-positive bacterium Rhodococcus rhodochrous NCIMB13064. Mutants resistant to the suicide substrate 1,2-dibromoethane lacked haloalkane dehalogenase activity and therefore could not utilize haloalkanes for growth. PCR analysis showed that these mutants had lost at least part of the dhaA gene.
Poelarends
G J
GJ
Department of Biochemistry, University of Groningen, 9747 AG Groningen, The Netherlands.
Wilkens
M
M
Larkin
M J
MJ
van Elsas
J D
JD
Janssen
D B
DB
D000473:Alkanes / Q000378:metabolism; D000498:Allyl Compounds / Q000378:metabolism*; D001673:Biodegradation, Environmental; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D005798:Genes, Bacterial; D006843:Hydrocarbons, Chlorinated; D006867:Hydrolases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D007306:Insecticides / Q000378:metabolism*; D009154:Mutation; D010957:Plasmids / Q000235:genetics; D011549:Pseudomonas / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D012988:Soil Microbiology
D000473:Alkanes; D000498:Allyl Compounds; D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; C023891:1,3-dichloro-1-propene; D006867:Hydrolases; C046137:haloalkane dehalogenase