TABLE 1.
Evidence for growth and sulfate reduction in batch cultures of four SRB grown lithotrophically and heterotrophicallya
| Species and growth phase | Lithotrophic growth characteristic
|
Heterotrophic growth characteristic
|
||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Organism characteristics | Pressure (lb/in2) | pH | OD600 | Protein concn (mg/ml) | Sulfate concn (mM) | Sulfide concn (mM) | Organism characteristics | Pressure (lb/in2) | pH | OD600 | Protein concn (mg/ml) | Sulfate concn (mM) | Sulfide concn (mM) | |
| Desulfovibrio desulfuricans | Gram-negative mixotroph with CO2-acetate | Gram-negative, incomplete oxidizer | ||||||||||||
| Initial | 15.1 | 7.09 | 0.068 ± 0.000 | 0.02 ± 0.000 | 21.3b ± 1.0 | ND | 10.0 | 6.49 | 0.049 ± 0.005 | 0.11 ± 0.01 | 19.9 ± 0.8 | 0.4 ± 0.3 | ||
| Final 1 | 8.2 | 7.45 | 0.164 ± 0.002 | 4.17 ± 0.24 | 0.0 ± 0.0 | 17.7 ± 3.7 | 10.8 | 6.72 | 0.224 ± 0.008 | 1.74 ± 0.04 | 13.9 ± 0.2 | 4.3 ± 0.1 | ||
| Final 2 | 7.7 | 7.40 | 0.167 ± 0.001 | 4.09 ± 0.13 | 0.0 ± 0.0 | 18.7 ± 0.9 | 10.9 | 6.72 | 0.229 ± 0.028 | 2.18 ± 0.28 | 14.0 ± 0.4 | 4.7 ± 0.3 | ||
| Desulfotomaculum acetoxidans | Gram-positive autotroph, acetyl-CoA pathway | Gram-positive, complete oxidizer, acetyl-CoA pathway | ||||||||||||
| Initial | 15.1 | 7.07 | 0.041 ± 0.000 | 0.03 ± 0.00 | 19.0 ± 0.3 | ND | 10.0 | 6.54 | 0.033 ± 0.003 | 0.15 ± 0.01 | 18.4 ± 0.2 | 0.3 ± 0.0 | ||
| Final 1 | 8.7 | 7.37 | 0.142 ± 0.011 | ND | 4.4 ± 1.1 | ND | 8.7 | 6.95 | 0.131 ± 0.004 | ND | 13.6 ± 0.2 | ND | ||
| Final 2 | 9.9 | 7.38 | 0.264 ± 0.016 | 3.18 ± 0.18 | 5.3 ± 1.0 | 12.0 ± 0.7 | 9.0 | 6.93 | 0.221 ± 0.010 | 1.64 ± 0.16 | 13.6 ± 0.2 | 3.4d ± 0.3 | ||
| Desulfobacter hydrogenophilus | Gram-negative autotroph, modified TCA cycle | Gram-negative, complete oxidizer, modified TCA cycle | ||||||||||||
| Initial | 15.1 | 6.96 | 0.060 ± 0.000 | 0.03 ± 0.00 | 19.2 ± 0.4 | ND | 10.0 | 6.43 | 0.097 ± 0.002 | 0.04 ± 0.00 | 18.4 ± 0.8 | 0.7 ± 0.0 | ||
| Final 1 | 7.7 | 7.39 | 0.378 ± 0.013 | 4.28 ± 0.26 | 0.1 ± 0.1 | 19.4 ± 0.2 | 9.8 | 7.07 | 0.360 ± 0.017 | 0.86 ± 0.04 | 7.8 ± 0.8 | 7.4 ± 0.5 | ||
| Final 2c | 15.2 | 7.10 | 0.037 ± 0.002 | 0.38 ± 0.28 | 18.4 ± 0.7 | 0.0 ± 0.0 | 9.8 | 7.09 | 0.381 ± 0.018 | 1.87 ± 0.08 | 8.4 ± 0.7 | 6.4 ± 0.3 | ||
| Desulfobacterium autotrophicum | Gram-negative autotroph, acetyl CoA pathway | Gram-negative, complete oxidizer, acetyl-CoA pathway | ||||||||||||
| Initial | 14.7 | 6.98 | 0.068 ± 0.000 | 0.04 ± 0.02 | 18.1 ± 0.2 | ND | 10.0 | 6.41 | 0.090 ± 0.001 | 0.27 ± 0.02 | 18.8 ± 0.4 | 0.4 ± 0.1 | ||
| Final 1 | 6.4 | 7.41 | 0.884 ± 0.001 | 4.65 ± 0.24 | 0.1 ± 0.0 | 22.0 ± 0.5 | 9.8 | 7.07 | 0.344 ± 0.008 | 2.32 ± 0.09 | 8.5 ± 1.5 | 7.8 ± 0.3 | ||
| Final 2 | 6.3 | 7.39 | 0.424 ± 0.002 | 4.66 ± 0.14 | 0.1 ± 0.0 | 20.8 ± 3.0 | 9.8 | 7.05 | 0.359 ± 0.015 | 0.72 ± 0.09 | 8.0 ± 1.4 | 7.5 ± 0.7 | ||
Sterile controls, under lithotrophic- and heterotrophic-growth conditions (respectively), were unchanged in pH (7.09 ± 0.01 and 6.51 ± 0.01), optical density (OD) (0.013 ± 0.003 and 0.014 ± 0.003), protein concentration (0.03 ± 0.00 and 0.01 ± 0.00 mg/ml), sulfate concentration (19.79 ± 0.82 and 22.53 ± 1.99 mM), sulfide concentration (0.44 ± 0.28 and 0.88 ± 0.20 mM), acetate concentration (0.0 ± 0.0 and 10.5 ± 2.6 mM), and pressure (15.0 ± 1.2 and 9.6 ± 0.2 lb/in2) over the duration of the incubation (380 and 168 h). ND, not determined.
Sample was compromised before sulfate was analyzed. Value shown is for an uninoculated control harvested at the same time.
This culture became oxidized due to stopper failure and did not grow.
Values are from a sample taken before substrate degradation was complete.