Table 1.

Partial protein enrichment of the mitochondrial ascorbic acid transporter from rat liver and potato.

		Protein (mg/ml)	Specific activity	Protein enrichment (fold)
Rat	Extract	28.5	0.027 ± 0.0042	–
	HTP	0.49	1.1 ± 0.22	40
Potato	Extract	8.4	0.12 ± 0.031	–
	HTP	1.3	0.25 ± 0.017	2.0

The uptake was started by adding 0.1 mM external [¹⁴C]ascorbic acid to the proteoliposomes in the absence of internal substrate. Other conditions as described in Methods. The activity of the reconstituted ascorbic acid transporter is expressed in nmol × mg protein⁻¹ × 10 min⁻¹ (specific activity).