| ARCHAEA> EURYARCHAEOTA> HALOBACTERIA |
PHYLUM HALOBACTERIA LINKS
| The following description of the Halobacteria came from Brock et al. (1994), Margulis and Schwartz (1998), Garrity et al. (2001 and 2003), and Black (2002). |
- I. SYNONYMS: Halophilic bacteria.
- II. PHYLUM CHARACTERISTICS:
- A. Structure
- Cell Form: Variable; cocci (text with tooltip) A coccus (cocci, pl.) is a spherical cell form. or rods (text with tooltip) A rod is an elongate cell form such that it has distinct ends (called poles). .
- Cell Wall: Archaebacterial; gram- (text with tooltip) A Gram - cell loses the blue-black crystal-violet color following destaining with alcohol during the Gram Stain procedure. Then, it takes on the color of the counterstain, typically iodine. .
- Motility: Non- motile (text with tooltip) A motile cell moves by means of flagella. cocci, or rods with polar flagella (text with tooltip) Polar flagella are those that emerge from the poles of the cell (rods or spirals). .
- B. Physiology
- O2 Tolerance: Aerobes (text with tooltip) Aerobes are those bacteria that require free oxygen for metabolism. or facultative anaerobes.
- Substrates: Chemoheterotrophs (text with tooltip) Chemoheterotrophs are those organisms that use compounds from the environment to provide metabolic energy. using amino acids (in absence of O2); photophosphorylation in presence of light and O2. All require large amounts of Na+ and K+ for growth. In anaerobic conditions, elemental sulfur, thiosulfate or nitrate can serve as electron acceptors (see products).
- Products: CO2 in aerobic conditions. In anaerobic conditions, they reduce elemental Sulfur (to S-2), or NO3 (to NO2 or NH4+).
- C. Other: Special lipids in the membranes; high concentrations of K ions in the cell.
- D. Ecology: Require NaCl concentration of 2mol/l; found in salt lakes, brines and salt-preserved products.
- A. Structure
| LITERATURE CITED Black, J. G. 2002. Microbiology, Principles and Explorations. 5th ed. John Wiley and Sons, Inc. New York. Gao, B. and R. S. Gupta. 2007. Phylogenetic analysis of proteins that are distinctive of Archaea and its main subgroups and the origin of methanogenesis. BMC Genomics. 8:86. http://www.biomedcentral.com/1471-2164/8/86. Garrity, G. M., M. Winters, and D. Searles. 2001. Bergey’s manual of systematic bacteriology. 2nd ed. Springer-Verlag. New York. Garrity, G. M., J. A. Bell, and T. G. Lilburn. 2003. Taxonomic Outline of the Prokaryotes. Bergey’s Manual of Systematic Bacteriology. 2nd edition. Release 4.0. Springer-Verlag. New York. pp. 1-397. Margulis, L. and K. Schwartz. 1988. Five kingdoms, an illustrated guide to the phyla of life on earth. 2nd Edition. W. H. Freeman and Co. New York. Margulis, L. and K. Schwartz. 1998. Five kingdoms, an illustrated guide to the phyla of life on earth. 3rd Edition. W. H. Freeman and Co. New York. Woese, C. R. and G. E. Fox. 1977. Phylogenetic structure of the prokaryotic domain: the primary kingdoms. Proceedings of the National Academy of Sciences USA. 74:5088-5090. Woese, C. R., O. Kandler, and M. L. Wheelis. 1990. Towards a natural system of organisms: Proposal for the domains Archaea, Bacteria, and Eucarya. Proc. Natl. Acad. Sci. USA. 87: 4576-4579. |
| By Jack R. Holt. Last revised: 02/06/2012 |
