TABLE 2.

Phosphotransacylase activity in cell extracts from selected strains of S. enterica^a

Strain (relevant genotype)	PTAC activity (μmol min−1 mg−1)b
	Propionyl-PO42−	Acetyl-PO42−	Propionyl-PO42− preferencec
Wild type (PduL+ Pta+)	8.9	3.5	2.5
BE188 (PduL− Pta+)	2.6	3.2	0.8
BE527 (PduL+ Pta−)	6.0	0.4	15.0
BE291 (PduL− Pta−)	ND	ND

^aCells were grown on NCE succinate minimal medium supplemented with 1,2-PD to ensure induction of the pdu operon.

^bPTAC assay mixtures contained 0.2 mM HS-CoA and 1 mM propionyl-PO₄²⁻ or acetyl-PO₄²⁻ and assay buffer. Activity was determined by monitoring the absorbance of reaction mixtures at 232 nm. ND, not detected (the lower detection limit of the assay is estimated to be 0.03 μmol min⁻¹ mg⁻¹).

^cPropionyl-PO₄²⁻ preference = (activity with propionyl-PO₄²⁻)/(activity with acetyl-PO₄²⁻).