TABLE 2.

Characteristics of strains CKU-1 and RKU-1

Strain	Diam (μm)	Flagella	Temp (°C)		pH		NaCl concn (%)		Doubling time (h) at:
			Range	Optimum	Range	Optimum	Range	Optimum	Optimum temp	In situ temp (52°C)
CKU-1	0.5–3.0	+	46–95	85	5.2–9.0	6.0	0.1–6.0	2.0	0.6	11.4
RKU-1	2.0–7.0 × 0.7–1.0	+	47–88	80	5.2–9.0	7.0	0.1–5.5	1.0	0.9	22.1

Substrates used	Metabolites	Growth response to elemental sulfur	Antibiotic sensitivitya	G+C content (%)
Yeast extract, proteinaceous substrates,b amino acids	Acetate, lactate, H2, CO2	No effect	R	37.8
Yeast extract, peptone, sugars,c cellulose	Acetate, lactate, H2, CO2	Inhibit	R, S, V, C	46.8

^aR, rifampin; S, streptomycin; V, vancomycin; C, chloramphenicol. 

^bPeptone or casein. 

^cGlucose, sucrose, maltose, or starch.