Thermococcus peptonophilus sp. nov., a fast-growing, extremely thermophilic archaebacterium isolated from deep-sea hydrothermal vents

Arch Microbiol. 1995 Sep;164(3):159-64.


Two extremely thermophilic archaebacteria, strains OG-1 and SM-2, were isolated from newly discovered deep-sea hydrothermal vent areas in the western Pacific ocean. These strains were cocci, obligately anaerobic Archaea about 0.7-2 microm in diameter. Optimum growth conditions for OG-1 and SM-2 were at 85-90 degrees C (range 60-100 degrees C), pH 6 (range pH 4-8), a NaCl concentration of 3% (range 1-5%), and a nutrient concentration (tryptone plus yeast extract) of 0.2% (range 0.005-5%). Elemental sulfur stimulated the growth rate fourfold. Ammonium slightly stimulated growth. Both tryptone and yeast extract allowed growth as sole carbon sources; these isolates were not able to utilize or grow exclusively on sucrose, glucose, maltose, succinate, pyruvate, propionate, acetate, or free amino acids. OG-1 showed the fastest growth rate within the genus Thermococcus. Growth was inhibited by rifampicin. The DNA G+C content was 52 mol%. Sequencing of their 16S rDNA gene fragment indicated that these isolates belonged to the genus Thermococcus. OG-1 and SM-2 were different than the described Thermococcus species. We propose that OG-1 belongs to a new species: Thermococcus peptonophilus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Archaea / classification*
  • Archaea / cytology
  • Archaea / isolation & purification*
  • Archaea / physiology
  • Base Composition
  • Base Sequence
  • Culture Media
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • DNA, Ribosomal / genetics
  • Hot Temperature
  • Hydrogen-Ion Concentration
  • Molecular Sequence Data
  • Pacific Ocean
  • RNA, Bacterial / genetics
  • RNA, Ribosomal, 16S / genetics
  • Seawater*
  • Sequence Homology, Nucleic Acid
  • Sodium Chloride / pharmacology
  • Water Microbiology*


  • Culture Media
  • DNA, Bacterial
  • DNA, Ribosomal
  • RNA, Bacterial
  • RNA, Ribosomal, 16S
  • Sodium Chloride