title: Degradation of various chlorophenols under alkaline conditions by gram-negative bacteria closely related to Ochrobactrum anthropi.
abstract: From concrete debris of a demolished herbicide production plant several Gram-negative bacterial strains were isolated, which exhibit metabolic capabilities for the degradation of 2,4-dichlorophenol (DCP)l), 4-chloro-2-methylphenol (MCP) and 4-chlorophenol (4-CP), while 2-chlorophenol (2-CP) was degraded at a slower rate. Degradative activity was inducible and was impeded by adding of 100 mg/l of chloramphenicol to growing cultures. The strains displayed alkaliphilic properties with optimum DCP/MCP degradation at pH values around 8.5-9.5; activity was observed up to pH values of 11. Degradation was most likely complete according to chlorine balances; formation of intermediary products was observed with MCP some time. Specific activity of up to 380 mumol/h.g dry mass was found within the concentration range of 10-20 mg/l DCP; higher concentrations retarded the activity with complete inhibition at 200-400 mg/l. Some of the strains carry plasmids whose presence was not unambiguously correlated to the degradative properties. Ribotyping revealed a high degree of relationship between the strains. Preliminary taxonomic investigations showed close relationship to Ochrobactrum anthropi.
authors.affiliation: Centre for Environmental Research Leipzig-Halle, Department of Environmental Microbiology, Leipzig, Germany.
authors.forename: R H
authors.initials: RH
authors.lastname: Müller
authors.forename: S
authors.initials: S
authors.lastname: Jorks
authors.forename: S
authors.initials: S
authors.lastname: Kleinsteuber
authors.forename: W
authors.initials: W
authors.lastname: Babel
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D001673:Biodegradation, Environmental; D002701:Chloramphenicol / Q000494:pharmacology; D002733:Chlorophenols / Q000378:metabolism*; D004352:Drug Resistance, Microbial; D016946:Gram-Negative Aerobic Rods and Cocci / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D006540:Herbicides / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D019216:Metals, Heavy / Q000494:pharmacology; D006899:Mixed Function Oxygenases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D002733:Chlorophenols; D006540:Herbicides; D019216:Metals, Heavy; D002701:Chloramphenicol; D006899:Mixed Function Oxygenases; C034354:2,4-dichlorophenol hydroxylase