Table 2.
Phenotypic characteristics that distinguish Desulfohalophilus alkaliarsenatis strain SLSR-1 from other halo-alkaliphilic sulfate- or sulfur-reducers isolated from soda lakes
| Characteristic | SLSR-1 | Desulfonatronospira thiodismutans a | Desulfohalobium retbaense b | Desulfonatronovibrio hydrogenovorans c |
|---|---|---|---|---|
| Habitat | Searles Lake, CA, USA | Kulanda Steppe, Russia | Retba Lake, Senegal | Lake Magadi, Kenya |
| Morphology | Vibroid | Vibroid | Rod | Vibroid |
| Motility | + | + | + | + |
| Flagella | + | + | + | + |
| Size (μm) | 0.5 × 3.0 | 0.6–0.8 × 2–30 | 0.7–0.9 × 1.0–3.0 | 0.5 × 1.5–2.0 |
| pH range (optimum) | 7.75–9.75 (9.25) | 8.3–10.5 (10) | 5.5–8.0 (6.5–7.0) | 8.0–10.2 (9.6) |
| Salt range (g/L) | 55–330 | 87–232 | 29–240 | 10–120 |
| Temperature range (opt.; °C) | 20–50 (44) | “Mesophilic” (43) | 25–40 (37) | (37) |
| G + C content (mole%) | 45.1 | 50.4 | 57.1 | 48.6 |
| Chemolithotrophy | ||||
| H2 | − | + | − | +d |
| S2 − + NO3 − | + | NDe | ND | ND |
| S2 − + As(V)d | + | ND | ND | ND |
| Electron donors | ||||
| Lactate | + | + | + | − |
| Pyruvate | + | + | + | − |
| Acetate | − | − | − | − |
| H2 + acetate | − | − | + | + |
| Formate | − | + | + | − |
| Ethanol | − | + | + | − |
| Malate | − | ND | − | − |
| Succinate | − | ND | − | ND |
| Propionate | − | ND | − | − |
| Citrate | − | ND | ND | |
| Glycerol | − | ND | − | − |
| Glucose | − | ND | − | ND |
| Fructose | − | ND | − | ND |
| Fumarate | − | ND | − | − |
| Electron acceptors | ||||
| Sulfate | + | + | + | + |
| Arsenate | + | ND | ND | ND |
| Nitrate | + | ND | ND | ND |
| Nitrite | − | ND | ND | ND |
| DMSO | − | ND | ND | |
| Sulfite; thiosulfate | + | +f | + | +f |
| Oxygen | − | − | ND | |
| Sulfur | − | ND | + | − |
| Fumarate | − | ND | ND | ND |
| Fe(III) | − | ND | ND | ND |
| Mn(IV) | − | ND | ND | ND |
| Selenate | − | ND | ND | ND |