The Phylogeny of Amycolata autotrophica, Kibdelosporangium aridum and Saccharothrix australiensis

SUMMARY: The phylogenetic relationships of Kibdelosporangium aridum and Saccharothrix australiensis were examined using reverse transcriptase sequencing of 16S ribosomal RNA. The sequences were aligned with other actinomycete sequences and a phylogenetic tree was constructed. K. aridum ATCC 39323 and S. australiensis ATCC 31947 formed distinct sublines within the family Pseudonocardiaceae. Their status as distinct genera was supported by the results of DNA: DNA pairing experiments. The inclusion of K. aridum and S. australiensis and two unpublished Amycolata spp. sequences in the rRNA analysis resulted in Amycolata autotrophica joining the family Pseudonocardiaceae. In previous studies, this strain had formed an isolated line of descent. It is proposed that the genera Amycolata and Kibdelosporangium be classified in the family Pseudonocardiaceae. Further work is needed to confirm the phylogeny of S. australiensis. Chemotaxonomic analyses of lipids and cell walls from S. australiensis support these findings and confirm previous work.