Degradation of chlorobenzenes by a strain of Acidovorax avenae isolated from a polluted aquifer

• Published in: Chemosphere (Oxford) Vol. 61; no. 1; pp. 98 - 106
• Main Authors: Monferrán, Magdalena V., Echenique, José R., Wunderlin, Daniel A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-09-2005; Elsevier
• Subjects: Acidovorax; Acidovorax avenae; Active sites; Amino Acid Sequence; Applied sciences; aquifers; aromatic ring hydroxylating dioxygenase; Aromatic-ring-hydroxylating dioxygenase (ARHDO); Biodegradation; Biodegradation of pollutants; Biodegradation, Environmental; Biological and medical sciences; Biological and physicochemical phenomena; Biotechnology; chlorinated hydrocarbons; Chlorobenzenes; Chlorobenzenes - metabolism; Comamonadaceae - genetics; Comamonadaceae - physiology; Decontamination. Miscellaneous; DNA, Bacterial - analysis; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; genes; groundwater contamination; Industrial applications and implications. Economical aspects; Molecular Sequence Data; Natural water pollution; nucleotide sequences; oxygenases; Pollution; Pollution, environment geology; Polymerase Chain Reaction; Soil and sediments pollution; Water Supply; Water treatment and pollution; Argentina, Cordoba, Cordoba, Suquia R; Biodegradation; Aromatic-ring-hydroxylating dioxygenase (ARHDO); Chlorobenzenes; Acidovorax avenae; Pseudomonadales; Microbial activity; Enzyme; Metabolic pathway; Soil pollution; Sediments; Polymerase chain reaction; Enzymatic activity; Decontamination; Chlorine Organic compounds; Bacteria; Pseudomonadaceae; Genetic identification; Catabolism; Aromatic compound; Water pollution; Bioremediation; Oxidoreductases; Microbial community
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2005.03.003

A subsurface microbial community was isolated from a polluted site of Suquía River (Córdoba—Argentina), acclimated during 15 days in aerobic conditions using 1,2-dichlorobenzene (1,2-DCB) as the sole carbon source. From this acclimated community, we isolated and identified by 16S rDNA analysis a strain of
Acidovorax avenae, which was able to perform the complete biodegradation of 1,2-DCB in two days affording stoichiometric amounts of chloride. This pure strain was also tested for biodegradation of chlorobenzene (CB); 1,3-DCB and 1,4-DCB, giving similar results to the experiments using 1,2-DCB.
The aromatic-ring-hydroxylating dioxygenase (ARHDO) α-subunit gene core, encoding the catalytic site of the large subunit of chlorobenzene dioxygenase, was detected by PCR amplification and confirmed by DNA sequencing. These results suggest that the isolated strain of
A. avenae could use a catabolic pathway, via ARHDO system, leading to the formation of chlorocatecols during the first steps of biodegradation, with further chloride release and subsequent paths that showed complete substrate consumption.