title: Distribution of 16S rRNA introns among the family Thermoproteaceae and their evolutionary implications.
abstract: Novel 16S rRNA introns were detected in four new strains within the family Thermoproteaceae. Pyrobaculum oguniense TE7(T) and Thermoproteus sp. IC-062 housed introns of 32 and 665-668 bp after positions 1205 and 1213 ( Escherichia coli numbering system), respectively. Caldivirga maquilingensis IC-167(T) had two introns of 37 and 140 bp after positions 901 and 908, respectively. Vulcanisaeta distributa IC-065 had a 691-bp intron after position 1391. All the introns larger than 650 bp encoded the LAGLI-DADG type proteins. The intron-encoded proteins of P. oguniense TE7(T) and Thermoproteus sp. IC-062 are cognate with the proteins encoded by introns inserted at the same position in other Pyrobaculum/ Thermoproteus strains and phylotypes. The intron-encoded protein of V. distributa IC-065 is partially related to that of a Pyrobaculum phylotype. A large-scale deletion in the second intron of Caldivirga maquilingensis IC-167(T) is suspected. Based on these newly found introns and hitherto known 16S rRNA introns, the evolutionary movements of the 16S rRNA introns and the encoded LAGLI-DADG type proteins are discussed.
authors.affiliation: Japan Collection of Microorganisms, RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan. ito@jcm.riken.go.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Itoh
authors.forename: Norimichi
authors.initials: N
authors.lastname: Nomura
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Sako
mesh_terms: D020816:Amino Acid Motifs; D001105:Archaea / Q000235:genetics; D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics; D019143:Evolution, Molecular; D007438:Introns; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D019624:Thermoproteaceae / Q000235:genetics*
chemical_list: D012336:RNA, Ribosomal, 16S