Rapid Biodegradation of the Herbicide 2,4-Dichlorophenoxyacetic Acid by Cupriavidus gilardii T-1.
Phytotoxicity and environmental pollution of residual herbicides have caused much public concern during the past several decades. An indigenous bacterial strain capable of degrading 2,4-dichlorophenoxyacetic acid (2,4-D), designated T-1, was isolated from soybean field soil and identified as Cupriavidus gilardii. Strain T-1 degraded 2,4-D 3.39 times more rapidly than the model strain Cupriavidus necator JMP134. T-1 could also efficiently degrade 2-methyl-4-chlorophenoxyacetic acid (MCPA), MCPA isooctyl ester, and 2-(2,4-dichlorophenoxy)propionic acid (2,4-DP). Suitable conditions for 2,4-D degradation were pH 7.0-9.0, 37-42 °C, and 4.0 mL of inoculums. Degradation of 2,4-D was concentration-dependent. 2,4-D was degraded to 2,4-dichlorophenol (2,4-DCP) by cleavage of the ether bond and then to 3,5-dichlorocatechol (3,5-DCC) via hydroxylation, followed by ortho-cleavage to cis-2-dichlorodiene lactone (CDL). The metabolites 2,4-DCP or 3,5-DCC at 10 mg L-1 were completely degraded within 16 h. Fast degradation of 2,4-D and its analogues highlights the potential for use of C. gilardii T-1 in bioremediation of phenoxyalkanoic acid herbicides.
['Wu|Xiangwei|X|http://orcid.org/0000-0003-3589-4051', 'Wang|Wenbo|W|', 'Liu|Junwei|J|', 'Pan|Dandan|D|', 'Tu|Xiaohui|X|', 'Lv|Pei|P|', 'Wang|Yi|Y|', 'Cao|Haiqun|H|http://orcid.org/0000-0001-9381-8896', 'Wang|Yawen|Y|', 'Hua|Rimao|R|http://orcid.org/0000-0002-5601-6568']
D015084:2,4-Dichlorophenoxyacetic Acid D001673:Biodegradation, Environmental D049921:Cupriavidus D006540:Herbicides D015394:Molecular Structure D012988:Soil Microbiology
biodegradation Cupriavidus gilardii 2,4-D phenoxyalkanoic acid herbicide degradation pathway degradation rate