ORIGINAL PAPER Biodegradation of 5-chloro-2-picolinic acid by novel identified co-metabolizing degrader Achromobacter sp. f1 Zhi-Guo Wu . Fang Wang . Li-Qun Ning . Robert D. Stedtfeld . Zong-Zheng Yang . Jing-Guo Cao . Hong-Jie Sheng . Xin Jiang Received: 17 September 2016 / Accepted: 31 January 2017 / Published online: 2 February 2017 Ó Springer Science+Business Media Dordrecht 2017 Abstract Several bacteria have been isolated to degrade 4-chloronitrobenzene. Degradation of 4-chloronitrobenzene by Cupriavidus sp. D4 produces 5-chloro-2-picolinic acid as a dead-end by-product, a potential pollutant. To date, no bacterium that degrades 5-chloro-2-picolinic acid has been reported. Strain f1, isolated from a soil polluted by 4-chloroni- trobenzene, was able to co-metabolize 5-chloro-2- picolinic acid in the presence of ethanol or other appropriate carbon sources. The strain was identified as Achromobacter sp. based on its physiological, biochemical characteristics, and 16S rRNA gene sequence analysis. The organism completely degraded 50, 100 and 200 mg L -1 of 5-chloro-2-picolinic acid within 48, 60, and 72 h, respectively. During the degradation of 5-chloro-2-picolinic acid, Cl - was released. The initial metabolic product of 5-chloro-2- picolinic acid was identified as 6-hydroxy-5-chloro-2- picolinic acid by LC–MS and NMR. Using a mixed culture of Achromobacter sp. f1 and Cupriavidus sp. D4 for degradation of 4-chloronitrobenzen, 5-chloro- 2-picolinic acid did not accumulate. Results infer that Achromobacter sp. f1 can be used for complete biodegradation of 4-chloronitrobenzene in remedial applications. Keywords 4-Chloronitrobenzene (4-CNB) Á 5- Chloro-2-picolinic acid (5-CPA) Á Achromobacter Á Cometabolically biodegradation Introduction Nitrobenzene compounds are widely used in the chemical industry as a chemical feedstock. Residues are typically observed in wastewaters of pharmaceu- tical, aniline, pesticide, and dyestuff industries (Nishino and Spain 1993; Wang et al. 2009). Nitrobenzene compounds are considered environmen- tal pollutions due to toxic, mutagenic and carcinogenic properties (Linch 1974; Weisburger et al. 1978; Steinwandter 1987). While physical and chemical methods have been used to remediate contaminants, Electronic supplementary material The online version of this article (doi:10.1007/s10532-017-9783-z) contains supple- mentary material, which is available to authorized users. Z.-G. Wu Á L.-Q. Ning Á Z.-Z. Yang Á J.-G. Cao College of Chemical Engineering and Materials Science, Tianjin University of Science & Technology, Tianjin 300457, People’s Republic of China F. Wang (&) Á H.-J. Sheng Á X. Jiang (&) Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People’s Republic of China e-mail: wangfang@issas.ac.cn X. Jiang e-mail: jiangxin@issas.ac.cn R. D. Stedtfeld Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI 48824, USA 123 Biodegradation (2017) 28:139–144 DOI 10.1007/s10532-017-9783-z