The genome of Streptomyces rimosus subsp. rimosus shows a novel structure compared to other Streptomyces using DNA/DNA microarray analysis.

DNA/DNA genome microarray analysis together with genome sequencing suggests that the genome of members of the genus Streptomyces would seem to have a common structure including a linear genomic structure, a core of common syntenous Actinomycete genes, the presence of species specific terminal regions and two intermediate group of syntenous genes that seem to be genus specific. We analyzed Streptomyces species using DNA/DNA microarray comparative genome analysis. Only Streptomyces rimosus failed to give a congruent genome pattern for the genes found in Streptomyces coelicolor. We expanded the analysis to include a number of strains related to the type strain of S. rimosus and obtained a similar divergence from the main body of Streptomyces species. These strains showed very close identity to the original strain with no gene deletion or duplication detected. The 16S rRNA sequences of these S. rimosus strains were confirmed as very similar to the S. rimosus sequences available from the Ribosomal Database Project. When the SSU ribosomal RNA phylogeny of S. rimosus is analyzed, the species is positioned at the edge of the Streptomyces clade. We conclude that S. rimosus represents a distinct evolutionary lineage making the species a worthy possibility for genome sequencing.