Table 1.

Rates of ATP Hydrolysis by Membrane Vesicles¹

Mutation	ATP hydrolysis2 (μmol/min/mg)	+ LDAO3 (fold increase4)	+ DCCD5 (% inhibition)
Wild type	0.9	3.9 (4.3)	80
R210Q/Q252R	0.25	3.2 (13)	< 5
P204T/R210Q/Q252R	0.2	2.5 (12.7)	< 5
R210Q/Q252K	0.5	2.4 (4.8)	< 5
P204T/R210Q/Q252K	0.35	1.75 (5)	< 5
R210Q	0.2	1.45 (7.2)	22

¹Rates shown are a typical set of values from three different experiments with similar results

²ATP hydrolysis has been measured using phenol red as indicated in Materials and Methods.

³ATP hydrolysis has been measured in the presence of 0.3% LDAO. Rates are given in μmol/min/mg.

⁴The fold increase, shown in parentheses, is the ratio of the rate of ATP hydrolysis in the presence of 0.3% LDAO to the rate in the absence of LDAO.

⁵Membrane vesicles were diluted 5-fold with buffer and incubated with 50 μM DCCD for 30 min at room temperature before assay, as described previously [20]. For the double and triple mutants it should be noted that the DCCD-inhibited rates were never significantly different from the similarly-treated controls.