TABLE 1.

Cellular physiological properties, phylogenetic affiliations, and enzymatic experimental conditions for deep-sea isolates of Epsilon- and Gammaproteobacteria examined in this study

Characteristic	Hydrogenimonas thermophila strain EP1-55-1%	Sulfurimonas autotrophica strain OK10	“Sulfurimonas paralvinella” strain GO25	Lebetimonas acidiphila strain Pd55	Sulfurovum lithotrophicum strain BKB42	Nitratifractor salsuginis strain E9137-1	Thioreductor micantisoli strain BKB25Ts-Y	Thiomicrospira thermophila strain I78
Class	Epsilon proteobacteria	Epsilon proteobacteria	Epsilon proteobacteria	Epsilon proteobacteria	Epsilon proteobacteria	Epsilon proteobacteria	Epsilon proteobacteria	Gamma proteobacteria
Subgroup or order	Group A	Group B	Group B	Group D	Group F	Group F	Group G	Thiotrichales
Place of isolation	Central Indian Ridge chimney	Okinawa Trough hydrothermal sediments	Okinawa Trough, Paralvinella's nest	Mariana Arc vent fluids	Okinawa Trough hydrothermal sediments	Okinawa Trough chimney	Okinawa Trough hydrothermal sediments	Mariana Arc vent fluids
Topt for growtha (°C)	55	25	30	50	30	37	32	35
Electron donor	H2	S0, S2O32−, sulfide	H2, S0	H2	S0, S2O32−	H2, S0b	H2	S0, S2O32−, sulfide
Electron acceptor	S0, NO3−, O2	O2	NO3−, O2	S0	NO3−, O2	NO3−, O2	S0, NO3−	O2
Microaerophilic growth	+	+	+	−	+	+	−	+
Cultivation conditions
Temp (°C)	55	25	30	50	30	37	32	35
Electron donor	H2	S2O32−	H2	H2	S2O32−	H2	H2	S2O32−
Electron acceptor	NO3−	O2	NO3−	S0	O2	NO3−	S0	O2
Enzyme assay
Temp (°C)	55 (45 for RubisCO)	25	30	50 (45 for RubisCO)	30	37	30	37
Reference(s)	52, 55	22, 52	52	57	23, 52	37, 52	36, 52	55

^aT_opt, optimum temperature.

^b*, S⁰ does not solely support the growth.