TABLE 1.
Strain/plasmid | Growth (OD600) with various iron sourcesa
|
|||||
---|---|---|---|---|---|---|
+Feb | −Fec | −Fe with hemoglobin (μg/ml)
|
||||
Hbf (50) | Hb (25) | Hb (10) | Hb (5) | |||
CU712 wild type | 4.5 | <0.1 | 4.8 | 2.8 | 0.5 | 0.3 |
CU712 hmuOΔ | 4.0 | <0.1 | 0.14 | 0.10 | ndd | nd |
CU712 hmuOΔ/pCUhmuO | 3.8 | <0.1 | 4.2 | 2.5 | nd | nd |
CU712 hmuOΔ/p37hmuO | 4.2 | <0.1 | 4.1 | 2.2 | nd | nd |
CU712 hmuOΔ/p1841 | 3.8 | <0.1 | 0.13 | 0.08 | nd | nd |
C7(−) wild type | 2.1 | <0.1 | 4.3 | 2.7 | 0.7 | 0.4 |
C7 hmuOΔ | 2.2 | <0.1 | 1.1 | 0.7 | nd | nd |
C7 hmuOΔ/pCM2.6 (vector) | 5.7e | <0.1 | 1.9 | 0.9 | nd | nd |
C7 hmuOΔ/pCD293 (hmuO+) | 5.9 | <0.1 | 5.5 | 2.6 | nd | nd |
C7 hmuOΔ-1841Δ | 2.0 | <0.1 | 0.9 | 0.5 | nd | nd |
1737 wild type | 6.4 | <0.1 | 5.8 | 3.5 | nd | nd |
1737 hmuOΔ | 6.8 | <0.1 | 6.6 | 3.3 | nd | nd |
OD600 was determined for each culture after growth for 20 to 22 h in mPGT medium. Values shown are results from a representative experiment. All experiments were repeated at least three times, and the results of each assay varied by less than 20% from the mean.
+Fe medium is mPGT with 1 μM FeSO4.
−Fe medium is mPGT with 3.6 μg/ml EDDA.
nd, not done.
C7 strains carrying pCM2.6 plasmids grow to higher densities than strains without plasmids.
Hb, hemoglobin.