S. Shima et al., THE PHYLOGENETIC POSITION OF HYDROGENOBACTER ACIDOPHILUS BASED ON 16SRIBOSOMAL-RNA SEQUENCE-ANALYSIS, FEMS microbiology letters, 119(1-2), 1994, pp. 119-122
Hydrogenobacter acidophilus strain 3H-1 is a thermoacidophilic, obliga
tely chemolithoautotrophic, hydrogen-oxidizer isolated from a Japanese
solfataric field. Strain 3H-1 requires elemental sulfur for growth. W
e used PCR to amplify the 16S rRNA gene of strain 3H-1, and sequenced
the amplification product directly. Phylogenetic analyses show strain
3H-1 is closely related to Aquifex pyrophilus and may be located in th
e deepest branch within the eubacterial phylogenetic tree. Sulfur-depe
ndency of the ancestral eubacterium is also discussed.