Archives of Microbiology

, Volume 149, Issue 2, pp 95–101

Pyrobaculum gen. nov., a new genus of neutrophilic, rod-shaped archaebacteria from continental solfataras growing optimally at 100°C


  • R. Huber
    • Lehrstuhl für MikrobiologieUniversität Regensburg
  • J. K. Kristjansson
    • University of Iceland
  • K. O. Stetter
    • Lehrstuhl für MikrobiologieUniversität Regensburg
Original Papers

DOI: 10.1007/BF00425072

Cite this article as:
Huber, R., Kristjansson, J.K. & Stetter, K.O. Arch. Microbiol. (1987) 149: 95. doi:10.1007/BF00425072


Seven members of a new group of rod-shaped hyperthermophilic neutrophilic archaebacteria were isolated from boiling neutral to alkaline solfataric waters from the Azores, Iceland, and Italy. The organisms are strict anaerobes, growing optimally at 100°C. The cells are motile due to peritrichous or bipolar polytrichous flagellation. The isolates grow facultatively chemolithoautotrophically or obligately heterotrophically. Molecular hydrogen or complex organic substances are used as electron donors. During heterotrophic growth, elemental sulfur, thiosulfate, sulfite, l(-)cystine and oxidized glutathione may serve as electron acceptors depending on the individual strain. Elemental sulfur is strictly required as an electron acceptor for autotrophic growth. The G+C content of the DNA is around 46 mol%. The isolates represent a new genus which we have named Pyrobaculum (the “fire stick”). Two species are described: the facultatively autotrophic Pyrobaculum islandicum (DSM 4184), which is the type species, and the obligately heterotrophic Pyrobaculum organotrophum (DSM 4185).

Key words

ArchaebacteriaHyperthermophilicSolfatara fieldsGeothermalSulfur

Copyright information

© Springer-Verlag 1987