A novel soil bacterial strain degrading pyridines

Environmental pollution has become one of the most crucial problems of the modern society. Pyridine and its derivatives are one of the most widespread classes of heterocyclic industrial contaminants. Due to rather tough safe levels, thorough purification of the waste waters containing these ecotoxicants is required. However the existing chemical methods are not efficient. On the contrary, microbiological approach seems quite promising. A new strain degrading alkylpyridines was isolated from the soil contaminated with pyridine containing wastes. The strain was identified as Arthrobacter sp. KM-4 (VKM Ac-1098D). The strain completely consumes pyridine (2.5 g/l), 2-methylpyridine (2.5 g/l), 4-methylpyridine (1.5 g/l) and 2,6-dimethylpyridine (3 g/l) in aquatic solutions in 24 h. The intermediate products of the biodegradation process were identified using gas chromatography-mass spectrometry (GC-MS). Degradation schemes were proposed for pyridine and 2-methylpyridine. Previously unknown pathway of pyridines microbial degradation via intermediate formation of pyrrolidines was reliably proved by mass spectra and following synthesis of the identified compounds. New culture significantly surpasses all the known strains in the pyridines' degrading efficiency. Arthrobacter sp. KM-4 is a promising culture for application for the purification of waste water.