Classification Higher order taxa Archaea; Euryarchaeota; Archaeoglobi; Archaeoglobales; Archaeoglobaceae; Species Archaeoglobus fulgidus, A. lithotrophicus, A. profundus, A. veneficus NCBI: Taxonomy (http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Tree&id=2&lvl=3&lin=f&keep=1&srchmode=1&unlock) Description and significance Archaeoglobus fulgidus is a sulphur-metabolizing organism. Known Archaeoglobales are anaerobes, most of which are hyperthermophiles. These hyperthermophilic marine sulphate reducers are only related to other bacterial sulphate reducers distantly and grow at very high temperatures. Most of these archaeoglobales are found in hydrothermal evnrionments such as hot springs, oil wells, and hydrothermal vents. Archaeoglobus species form iron sulphide which is known to cause corrision of steel and iron in both oil and gas processing systems. Genome structure Archaeoglobus fulgidus is the first sulphur-metabolizing organism to have its genome sequence determined. Their genome is a single, circular chromosome of 2,178,400 base pairs with an average of 48.5% G+C content. There are two regions of high G+C conentent (53% and above) which contain genes for ribosomal RNAs, proteins that are involved in the biosysnthems of hemAB, along with several transporters. There are also three regions of lowG+C content (less than 39%). The organism has a predicted total of 2,436 coding sequences of which a quarter of it encode for proteins that are unique to the archaeal domain while another quarter of it is used to encode preserved proteins of which their functions have not yet been determined but are expressed in other archaeons. It is important to note that there are also many gene dulplications in the genome and the duplicated proteins are not identical. Cell structure and metabolism Archaeoglobus fulgidus have cells that are irregular spheres (cocci) with a glycoprotein envelope and monopolar flagella. Archaeoglobus metabolic pathway is a sulfur-oxide reduction pathway. The enzyme adenylsulfate reductase is synthesized via 1) where sulphate is activated to adenylylsulfate 2) then adenylylsulfate is then reduced to sulfite 3) followed by adenylylsulfate reductase synthesis. Application to Biotechnology When subjected to stress, they can produce biofilms which have been applied towards industrial purposes of detoxifying contaminated metals and since they live in extremely high temperatures, there are hope that heat stable enzymes may be derived. Current Research 1) When Archaeoglobus fulgidus is aggravated with heat it produces the intracellular organic solute di-myo-inositol phosphate (DIP) and accumulates diglycerol phosphate (DGP) in response to osmotic stress. But when both heat and osmotic stresses are applied, Archaeoglobus fulgidus increases its production of glycero-phospho-myo-inositol (GPI). This experiment established the pathways for the biosynthesis of these three solutes. The pathways were established based on the relevant enzymatic activities detection and NMR analysis characterization of the intermediate metabolites.
2) Archaeoglobus fulgidus was found in the oil field waters from an oil production platform in the North Sea. Results found that they grow in oil reservoirs at 70-80°C and contribute to the formation of hydrogen sulfide in the environment. Archaeoglobus fulgidus showed a complete 100% DNA-DNA homology with A. fulgidus Z, suggesting that Archaeoglobus fulgidus belonged to the species A. fulgidus. 
3) Archaeoglobus fulgidus was heat shocked and its response was studied using whole-genome microarrays. The study revealed that about 250 of 2410 open reading frames showed an increase or decrease transcript abudance based upon expression profile results. These transcript abundance span a range of cells functions, including amino acid abundance, energy production, and signal transduction. 
References & LaPaglia, C., Patricia L. 1997. Stress-Induced Production of Biofilm in the hyperthermophile Archaeoglobus fulgidus. Applied and Environmental Microbiology Vol. 63, No. 8: 3158-3163.
 Hans-Peter Klenk, Rebecca A. Clayton, Jean-Francois Tomb, Owen White, Karen E. Nelson, Karen A. Ketchum, Robert J. Dodson, Michelle Gwinn, Erin K. Hickey, Jeremy D. Peterson, Delwood L. Richardson, Anthony R. Kerlavage, David E. Graham, Nikos C. Kyrpides, Robert D. Fleischmann, John Quackenbush, Norman H. Lee, Granger G. Sutton, Steven Gill, Ewen F. Kirkness, Brian A. Dougherty, Keith McKenney, Mark D. Adams, Brendan Loftus, Scott Peterson, Claudia I. Reich, Leslie K. McNeil, Jonathan H. Badger, Anna Glodek, Lixin Zhou, Ross Overbeek, Jeannine D. Gocayne, Janice F. Weidman, Lisa McDonald, Teresa Utterback, Matthew D. Cotton, Tracy Spriggs, Patricia Artiach, Brian P. Kaine, Sean M. Sykes, Paul W. Sadow, Kurt P. D'Andrea, Cheryl Bowman, Claire Fujii, Stacey A. Garland, Tanya M. Mason, Gary J. Olsen, Claire M. Fraser, Hamilton O. Smith, Carl R. Woese and J. Craig. The complete genome sequence of the hyperthermophilic, sulphate-reducing archaeon Archaeoglobus fulgidus Vente Nature 390, 364-370 (27 November 1997) | doi:10.1038/37052.  Nuno Borges, Luís G. Gonçalves, Marta V. Rodrigues, Filipa Siopa, Rita Ventura, Christopher Maycock, Pedro Lamosa, and Helena Santos. Biosynthetic Pathways of Inositol and Glycerol Phosphodiesters Used by the Hyperthermophile Archaeoglobus fulgidus in Stress Adaptation. Journal of Bacteriology. 2006 December; 188(23): 8128–8135.  Janiche Beeder, Roald Kåre Nilsen, Jan Thomas Rosnes, Terje Torsvik, and Torleiv Lien. Archaeoglobus fulgidus Isolated from Hot North Sea Oil Field Waters. Appl Environ Microbiol. 1994 April; 60(4): 1227–1231.
 Lars Rohlin, Jonathan D. Trent, Kirsty Salmon, Unmi Kim, Robert P. Gunsalus, and James C. Liao. Heat Shock Response of Archaeoglobus fulgidus. Journal of Bacteriology. 2005 September; 187(17): 6046–6057.
Edited by Mike Sha, student of Rachel Larsen at UCSD.