Table 1.

Extremophiles with completely sequenced genomes

Organism	Domain*	Genome size	Phenotype†	Reference
		(base pairs)
Methanococcus jannaschii	AE	1,644,970	H	[3]
Methanobacterium	AE	1,751,377	T	[4]
thermoautotrophicum
Archaeoglobus fulgidus	AE	2,178,400	H	[5]
Aquifex aeolicus	B	1,551,335	H	[6]
Pyrococcus horikoshii	AE	1,738,505	H	[7]
Thermotoga maritima	B	1,860,725	H	[8]
Aeropyrum pernix	AC	1,699,695	H	[9]
Thermoplasma acidophilum	AE	1,564,905	T	[1]
Halobacterium strain	AE	2,014,239	EH	[10]
NRC-1
Pyrococcus abyssii	AE	1,765,505	H	[11]

^*Domains: A, Archaea; E, Euryarchaeota; C, Crenarchaeota; B, Bacteria. ^†Phenotypes: H, hyperthermophile (growth optima > 80°C); T, thermophile (growth optima > 40°C); EH, extreme halophile (absolute growth requirement for NaCl > 2 M NaCl).