TABLE 5.

Siderophore production by C. diphtheriae strains

Supplement to PGTH mediumSiderophore unitsa (SD)
C717371737/sidAN
Fe (10 μM)6.6 (2.2)1.4 (0.5)1.9 (1.2)
None65.5 (3.7)5.5 (1.7)4.6 (2.3)
EDDA (1 μM)58.7 (8.7)33.0 (2.6)29.7 (5.7)
  • a Siderophore units were determined as described previously (45). Values are the mean of three experiments ± standard deviation.