Table 1.

The purity of plasma membrane isolated from tomato roots was analyzed by the activity of various inhibitor-sensitive ATPases in the membrane fraction.

	Na3VO4	KNO3	NaN3	Na2MoO4
1.0 mM	0.881 ± 0.02	0.091 ± 0.01	0.057 ± 0.05	0.022 ± 0.02
0.2 mM	0.874 ± 0.04	0.079 ± 0.02	0.038 ± 0.08	0.029 ± 0.05
0.02 mM	0.91 ± 0.02	0.066 ± 0.02	0.05 ± 0.03	0.032 ± 0.07

The membrane was isolated from tomato roots subjected to normal and oxlow-phosphate stress conditions. The values are the means and SD of 10 replicates from two independent experiments.