Table 2.

Comparison of properties of Methanosaeta species

Property	Value
	“M. pelagica”	M. conciliia	M. thermophilaa	M. harundinaceaa
Type strain	03d30q	GP6	PT	8Ac
Habitat	Tidal flat sediment	Anaerobic digester	Anaerobic digester	Anaerobic digester
Optimum growth conditions
Temp (°C)	30	35–40	55–60	34—37
pH	7.5	7.1–7.5	6.5–6.7	7.2–7.6
Na+ concn (M)	0.28	<0.06	<0.13	<0.02
Effect on yeast extract for growth	Stimulate	Inhibit	Inhibitb	Required
G+C content (mol%)	45.4 (HPLC)	50.3 (Tm)c	52.7 (HPLC)	55.7 (Tm)

^aReference data are from Patel (45) and Ma et al. (30).

^bYeast extract inhibits the growth of some strains of M. thermophila.

^cT_m, melting temperature.