Reclassification of Arthrobacter duodecadis Lochhead 1958 as Tetrasphaera duodecadis comb. nov. and emended description of the genus Tetrasphaera

Phylogenetic analysis based on 16S rRNA gene sequences and chemotaxonomic features of Arthrobacter duodecadis Lochhead 1958 indicated that the bacterium belonged within the genus Tetrasphaera. A. duodecadis IAM 14868(T) could be distinguished from other species by the presence of 3-hydroxy meso-diaminopimelic acid in the peptidoglycan and a series of 10-methyl fatty acids. In addition, DNA-DNA relatedness studies indicated that the strain belonged to a genomic species that could be readily distinguished from its nearest neighbours, the type strains of Tetrasphaera elongata, Tetrasphaera japonica and Tetrasphaera australiensis. These features support our proposal to reclassify A. duodecadis in the genus Tetrasphaera, as Tetrasphaera duodecadis comb. nov. The type strain is IAM 14868(T) (=NBRC 12959(T) = ATCC 13347(T) = NCIMB 9222(T)). An emended description of the genus Tetrasphaera is given.