© BioMed Central Ltd 2002
Published: 17 January 2002
Pyrobaculum aerophilum is a hyperthermophilic crenachaeon that cannot tolerate the presence of elemental sulfur. In the January 22 issue of Proceedings of the National Academy of Sciences, Fitz-Gibbon et al. report the complete genome sequence of the P. aerophilum IM2 strain that was isolated from a boiling marine water hole in Maronti Beach, Italy (Proc Natl Acad Sci USA 2002, 99:984-989). The genome is 2.2 Mb long, has a 51% G+C content, and contains 2,587 predicted proteins. They found examples of instability of mononucleotide runs and failed to find evidence for a mismatch repair system, suggesting a 'mutator phenotype'. P. aerophilum lacks 5' untranslated regions suggesting an unusual mechanism for translation initiation. The genome contains enzymes for the glyoxylate cycle, 2-oxoacid dehydrogenase multienzyme complexes, and glycolysis. The P. aerophilum genome has inactivated adenylsulfate reductase genes, explaining its sulfur intolerance and offering a means for developing a genetic system based on selection for a sulfur-tolerance plasmid.