title: The phylogenetic relationships of three sulfur dependent archaebacteria.
abstract: Oligonucleotide catalogs have been determined for the 16S ribosomal RNAs of three sulfur dependent (i.e. "thermoacidophilic") archaebacteria--Sulfolobus acidocaldarius, S. solfataricus, and Thermoproteus tenax.  The three form a group specifically related to one another, but are only distantly related to the other archaebacteria--i.e. the group comprising the methanogens, extreme halophiles, and (peripherially) the genus Thermoplasma.  The three catalogs exhibit two features unique among bacteria:  (1) an unusually high number of long pyrimidine runs, and (2) a remarkably high number of (post-transcriptionally) modified nucleotides.
authors.affiliation: Department of Genetics and Development, University of Illinois, Urbana 61801, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Woese
authors.forename: R
authors.initials: R
authors.lastname: Gupta
authors.forename: C M
authors.initials: CM
authors.lastname: Hahn
authors.forename: W
authors.initials: W
authors.lastname: Zillig
authors.forename: J
authors.initials: J
authors.lastname: Tu
mesh_terms: D001105:Archaea / Q000145:classification* / Q000235:genetics*; D001483:Base Sequence; D005075:Biological Evolution; D009841:Oligonucleotides; D010802:Phylogeny; D019642:RNA, Archaeal; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D016944:Sulfolobus / Q000145:classification* / Q000235:genetics; D019624:Thermoproteaceae / Q000145:classification* / Q000235:genetics
chemical_list: D009841:Oligonucleotides; D019642:RNA, Archaeal; D012336:RNA, Ribosomal, 16S