Degradation of 4-chloro-2-methylphenol by an activated sludge isolate and its taxonomic description.
The Gram-negative strain S1, isolated from activated sludge, metabolized 4-chloro-2-methylphenol by an inducible pathway via a modified ortho-cleavage route as indicated by a transiently secreted intermediate, identified as 2-methyl-4-carboxymethylenebut-2-en-4-olide by gas chromatography/mass spectrometry. Beside 4-chloro-2-methylphenol only 2,4-dichlorophenol and 4-chlorophenol were totally degraded, without an accumulation of intermediates. The chlorinated phenols tested induced activities of 2,4-dichlorophenol hydroxylase and catechol 1,2-dioxygenase type II. Phenol itself appeared to be degraded more efficiently via a separate, inducible ortho-cleavage pathway. The strain was characterized with respect to its physiological and chemotaxonomic properties. The fatty acid profile, the presence of spermidine as main polyamine, and of ubiquinone Q-10 allowed the allocation of the strain into the alpha-2 subclass of the Proteobacteria. Ochrobactrum anthropi was indicated by fatty acid analysis as the most similar organism, however, differences in a number of physiological features (e.g. absence of nitrate reduction) and pattern of soluble proteins distinguished strain S1 from this species.
Lechner
U
U
Institute of Microbiology, Martin-Luther-University Halle, Germany.
Baumbach
R
R
Becker
D
D
Kitunen
V
V
Auling
G
G
Salkinoja-Salonen
M
M
D001673:Biodegradation, Environmental; D002733:Chlorophenols / Q000378:metabolism; D003408:Cresols / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006090:Gram-Negative Bacteria / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D013058:Mass Spectrometry; D010636:Phenols / Q000378:metabolism; D012722:Sewage
D002733:Chlorophenols; D003408:Cresols; D010636:Phenols; D012722:Sewage; C019292:4-chloro-2-cresol; C029107:4-chlorophenol; C004762:2,4-dichlorophenol