Suprageneric classification of thermoactinomyces vulgaris by nucleotide sequencing of 5S ribosomal RNA.

The 5S rRNA nucleotide sequence of Thermoactinomyces vulgaris was determined and compared with published sequences of representative Gram-positive bacteria. The primary and secondary structure of the sequence is of the type characteristic of Gram-positive bacteria that have DNA with a low proportion of guanine plus cytosine. It was evident from the phylogenetic trees that T. vulgaris has little in common with actinomycetes but is related to the genus Bacillus, showing a moderately high relationship with B. stearothermophilus. The taxonomic implications of these relationships are discussed and an emended description of the family Bacillaceae is given.