Organism	Category	Genome Abbreviation	ORFs	Physiological condition
Pyrococcus horikoshii (Strain OT3) (Kawarabayasi et al., 1998)	archaea	OT	2061	98° C, anaerobe
Aquifex aeolicus (Deckert et al., 1998)	eubacteria, gram negative	AA	1522	95° C
Methanococcus janaschii (Bult et al., 1996)	archaea	MJ	1735	85° C, anaerobe
Archaeoglobus fulgidus (Klenk et al., 1997)	archaea	AF	2409	83° C, anaerobe
Methanobacterium thermoautotrophicum (Smith et al., 1997)	archaea	MT	1869	65° C, anaerobe
Haemophilus influenzae (Fleischmann et al., 1995)	eubacteria, gram negative	HI	1680	mesophilic temp.
Mycoplasma genitalium (Fraser et al., 1995)	eubacteria, gram positive	MG	470	mesophilic temp.
Mycoplasma pneumoniae (Himmelreich et al., 1996)	eubacteria, gram positive	MP	677	mesophilic temp.
Helicobactor pylori (Tomb et al., 1997)	eubacteria, gram negative	HI	1590	mesophilic temp.
Escherichia coli (Blattner et al., 1997)	eubacteria, gram negative	EC	4288	mesophilic temp.
Synechocystis sp. (Kaneko et al., 1996)	cyanobacteria	SS	3168	mesophilic temp.
Saccharomyces cerevisiae (Goffeau et al., 1997)	eukaryote, fungus	SC	6218	mesophilic temp.

Table 1. List of Organisms.

The table lists the twelve organisms whose sequences are used in calculation. Column three shows the two-letter abbreviations for the genomes of the organisms listed in the first column. The fourth column lists the number of proteins in the genome. The last column shows the physiological temperatures of thermophiles. For mesophiles we referred to 'mesophilic temperatures' which range from 10 to 45 ° C.