, 10:327

Structural analysis of the plasmid pTA1 isolated from the thermoacidophilic archaeon Thermoplasma acidophilum

  • Kan Yamashiro
  • Shin-ichi Yokobori
  • Tairo Oshima
  • Akihiko Yamagishi
Original Paper

DOI: 10.1007/s00792-005-0502-z

Cite this article as:
Yamashiro, K., Yokobori, S., Oshima, T. et al. Extremophiles (2006) 10: 327. doi:10.1007/s00792-005-0502-z


Thermoplasma acidophilum is a thermoacidophilic archaeon that grows optimally at pH1.8 and 56°C and has no cell wall. Plasmid pTA1 was found in some strains of the species. We sequenced plasmid pTA1 and analyzed the open reading frames (ORFs). pTA1 was found to be a circular DNA molecule of 15,723 bp. Eighteen ORFs were found; none of the gene products except ORF1 had sequence similarity to known proteins. ORF1 showed similarity to Cdc6, which is involved in genome-replication initiation in Eukarya and Archaea. T. acidophilum has two Cdc6 homologues in the genome. The homologue found in pTA1 is most similar to Tvo3, one of the three Cdc6 homologues found in the genome of Thermoplasma volcanium, among all of the Cdc6 family proteins. The phylogenetic analysis suggested that plasmid pTA1 is possibly originated from the chromosomal DNA of Thermoplasma.


Archaea Cell division protein 6 Cdc6 Phylogenetic tree Plasmid pTA1 Thermoplasma acidophilum 



Open reading frame


Cell division control protein 6


Ribosome binding site


Non coding region


Polycystic kidney disease


Transcription factor IIB


Transcription factor B recognition elemen

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Kan Yamashiro
    • 1
  • Shin-ichi Yokobori
    • 1
  • Tairo Oshima
    • 1
  • Akihiko Yamagishi
    • 1
  1. 1.Department of Molecular BiologyTokyo University of Pharmacy and Life ScienceHachioji, Tokyo 192-0392Japan

Personalised recommendations