TABLE 3.

In vitro measurements of PDHc in E. coli RM201 and MC4100 cell extract^a

Strain	PDHc (nmol of ferricyanide reduced/min/mg of protein)
	Anaerobic	Fumarate	Nitrate	Aerobic
RM201	26 ± 2.1	42 ± 3.1	83 ± 4.2	131 ± 8.5
MC4100	22 ± 1.4	30 ± 5.3	67 ± 4.6	128 ± 6.7

^aCells were obtained from anaerobic glucose-limited chemostat cultures with nitrate (5 mM), with fumarate (25 mM), with no electron acceptor (anaerobic), or aerobically (pH = 6.5, D = 0.1 h⁻¹) as indicated.