Structures of Paracrystalline Protein Layers from the Hyperthermophilic Archaeobacterium Pyrobaculum

  • Barry M. Phipps
Part of the NATO ASI Series book series (NSSA, volume 252)


Members of the recently discovered archaeobacterial genus Pyrobaculum are sulfur-reducing hyperthermophiles which grow optimally at 100°C (Huber et al., 1987). All known strains were isolated from superheated, sulfurous fresh water springs or from the superheated outflow of a geothermal power plant. The cells are rod-shaped and vary in length up to 8µm, but their diameter is strikingly uniform. Two strains have been characterized in detail and were found to represent different species, Pyrobaculum islandicum (strain GEO3) and Pyrobaculum organotrophum (strain H10). P. islandicum is a facultative heterotroph capable of chemolithoautotrophic growth on sulfur, H2, and CO2, while P. organotrophum is strictly organotrophic. This Chapter reviews the results of investigations into the structure of the cell envelopes of these interesting archaeobacteria (Baumeister et al., 1989, 1990; Phipps et al., 1990, 1991). An element of the cell envelope of most archaeobacteria is a 2D paracrystalline array of protein or glycoprotein subunits, or S-layer, which is often directly adjacent to the cytoplasmic membrane (König, 1988). The array subunit is typically a complex, multi-domain protein and often possesses a putative membrane anchor domain (Baumeister et al., 1989). The unusual structures of Pyrobaculum S-layers are described, and the possible functional roles they fulfill are discussed.


Cytoplasmic Membrane Cell Envelope Protein Array Rotational Alignment Geothermal Power Plant 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Baumeister, W., and Hegerl, R., 1986, Can S-layers make bacterial connexons?, FEMS Microbiol. Lett. 36: 119.CrossRefGoogle Scholar
  2. Baumeister, W., Wildhaber, I., and Phipps, B.M., 1989, Principles of organization in eubacterial and archaebacterial surface proteins, Can. J. Microbiol. 35: 215.PubMedCrossRefGoogle Scholar
  3. Baumeister, W., Lembcke, G., Dürr, R., and Phipps, B., 1990, Electron crystallography of bacterial surface proteins, in: “Electron Crystallography of Organic Molecules,” J.R. Fryer and D.L. Dorset, eds., Kluwer Academic Publishers, Amsterdam.Google Scholar
  4. Huber, R., Kristjansson, J.K., and Stetter, KO., 1987, Pyrobaculum gen. nov., a new genus of neutrophilic, rod-shaped archaebacteria from continental sol-fataras growing optimally at 100°C, Arch. MicrobioL 149: 95.Google Scholar
  5. König, H., 1988, Archaebacterial cell envelopes, Can. J. Microbiol. 34: 395.CrossRefGoogle Scholar
  6. Messner, P., Pum, D., Sara, M., Stetter, KO., and Sleytr, U.B., 1986, Ultra-structure of the cell envelope of the archaebacteria Thermoproteus tenax and Thermoproteus neutrophilus, J. BacterioL 166: 1046.PubMedGoogle Scholar
  7. Phipps, B.M., Engelhardt, H., Huber, R., and Baumeister, W., 1990, Three-dimensional structure of the crystalline protein envelope layer of the hyperthermophilic archaebacterium Pyrobaculum islandicum, J. Struct. Biol. 103: 152.CrossRefGoogle Scholar
  8. Phipps, B.M., Huber, R., and Baumeister, W., 1991, The cell envelope of the hyperthermophilic archaebacterium Pyrobaculum organotrophum consists of two regularly arrayed protein layers: three-dimensional structure of the outer layer, Molec. MicrobioL 5: 253.CrossRefGoogle Scholar
  9. Saxton, W.O., and Baumeister, W., 1982, The correlation averaging of a regularly arranged bacterial cell envelope protein, J. Microsc. 127: 127.PubMedCrossRefGoogle Scholar
  10. Saxton, W.O., Baumeister, W., and Hahn, M., 1984, Three-dimensional reconstruction of imperfect two-dimensional crystals, Ultramicroscopy 13: 57.PubMedCrossRefGoogle Scholar
  11. Wildhaber, I., and Baumeister, W., 1987, The cell envelope of Thermoproteus tenax: three-dimensional structure of the surface layer and its role in shape maintenance, EMBO J. 6: 1475.PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1993

Authors and Affiliations

  • Barry M. Phipps
    • 1
  1. 1.Institute for Biological SciencesNational Research CouncilOttawaCanada

Personalised recommendations