TABLE 2.

Final absorbance at 600 nm of frdA::cat⁺ strain cultures grown in MHB or MEM (with or without substrate) for 26 h

Substrate (28 mM)	Absorbance at 600 nm in MHB	Absorbance at 600 nm in MEM	Growth stimulusa
None	0.24 ± 0.01	0.01 ± 0.00
Citrate	0.30 ± 0.02	0.01 ± 0.00	N
α-Ketoglutarate	0.28 ± 0.01	0.01 ± 0.00	N
Succinate	0.29 ± 0.01	0.01 ± 0.00	N
Glutamate	0.24 ± 0.01	0.01 ± 0.00	N
Proline	0.24 ± 0.01	0.01 ± 0.00	N
Acetate	0.27 ± 0.01	0.01 ± 0.00	N
Pyruvate	0.56 ± 0.02	0.26 ± 0.02	Y
Oxaloacetate	0.52 ± 0.01	0.31 ± 0.01	Y
Malate	0.69 ± 0.04	0.49 ± 0.02	Y
Fumarate	0.67 ± 0.03	0.57 ± 0.02	Y
Aspartate	0.92 ± 0.05	0.41 ± 0.01	Y
Serine	0.51 ± 0.02	0.01 ± 0.00	Y or N

^aY, yes; N, no.