TABLE 4.

Inhibition of orotate uptake by different compounds^a

Inhibitor	Inhibition (%) at concn (mM) of inhibitor
	0.1	0.5	1	10
Aspartate			2	60
Fumarate	78
l-Malate	83	97
d-Malate	14	42	60	95
Succinate	80
Succinamic acid	40	27	54	90
Succinamideb		3	53
Chlorosuccinate	48	78	86	96
Itaconate	44	44	51	74
Mesaconic acid	20	56	70	74
Carbamoyl aspartate	46	76	79	94

^aS. meliloti Rm8002 cultures were grown in M9 medium with 0.2% aspartate as the carbon source. The cultures were washed and resuspended in M9 medium without a carbon source. Assays were performed using 25 μM [³H]orotate with the carbon substrate tested as the inhibitor. 

^b0.4 and 2 mM succinamide.