Arthrobacter oxydans DSM 419 and DSM 420 have chemical and microbiological properties that are consistent with assignment to the genus Arthrobacter. Both organisms have the lysine-alanine-threonine-alanine peptidoglycan type. DNA-DNA pairing studies indicated that A. oxydans DSM 419 should be reclassified as Arthrobacter ureafaciens and that A. oxydans DSM 420T forms the nucleus of a distinct genomic species. We propose that A. oxydans DSM 420 should be reclassified as Arthrobacter nicotinovorans sp. nov. The type strain is strain DSM 420.