1,2,3-Trichloropropane (TCP) is a toxic compound that is recalcitrant to biodegradation in the environment. Attempts to isolate TCP-degrading organisms using enrichment cultivation have failed. A potential biodegradation pathway starts with hydrolytic dehalogenation to 2,3-dichloro-1-propanol (DCP), followed by oxidative metabolism. To obtain a practically applicable TCP-degrading organism, we introduced an engineered haloalkane dehalogenase with improved TCP degradation activity into the DCP-degrading bacterium Pseudomonas putida MC4. For this purpose, the dehalogenase gene (dhaA31) was cloned behind the constitutive dhlA promoter and was introduced into the genome of strain MC4 using a transposon delivery system. The transposon-located antibiotic resistance marker was subsequently removed using a resolvase step. Growth of the resulting engineered bacterium, P. putida MC4-5222, on TCP was indeed observed, and all organic chlorine was released as chloride. A packed-bed reactor with immobilized cells of strain MC4-5222 degraded >95% of influent TCP (0.33 mM) under continuous-flow conditions, with stoichiometric release of inorganic chloride. The results demonstrate the successful use of a laboratory-evolved dehalogenase and genetic engineering to produce an effective, plasmid-free, and stable whole-cell biocatalyst for the aerobic bioremediation of a recalcitrant chlorinated hydrocarbon.

• MeSH
• biodegradace MeSH
• biotransformace MeSH
• exprese genu MeSH
• hydrolasy genetika   metabolismus   MeSH
• látky znečišťující životní prostředí metabolismus   MeSH
• metabolické inženýrství * MeSH
• metabolické sítě a dráhy genetika   MeSH
• plazmidy MeSH
• propan analogy a deriváty   metabolismus   MeSH
• Pseudomonas putida genetika   metabolismus   MeSH
• rekombinantní proteiny genetika   metabolismus   MeSH
• selekce (genetika) MeSH
• transpozibilní elementy DNA MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH