Effects of Inorganic and Organic Anions on the Transport of Phosphoenol-Pyruvate Across the Erythrocyte Membrane(MEMBRANE PROTEINS AND TRANSPORT-II)

概要

論文の詳細を見る
Phosphoenolpyruvate is transported across the erythrocyte membrane by a carrier-mediated transport system. The transport of phosphoenolpyruvate was competitively inhibited by inorganic phosphate (Ki=24mM) and pyridoxal 5-P (Ki=0.2mM), whereas the transport was non-competitively inhibited by L-(+)-lactate (Ki=37mM). Specific inhibitors for the inorganic anion transport system such as 4, 4'-diisothiocyanostilbene-2, 2'-disulfonic acid strongly inhibited the phosphoenolpyruvate transport. Inhibitors for the monocarboxylate transport system, including p-chlormercuribenzoic acid and α-cyano-4-hydroxycinnamate, had less inhibitory effects on the phosphoenolpyruvate transport as high as 100μM. The transport was inhibited irreversibly by treating erythrocytes with pryridoxal 5-P/NaBH_4. Transport activities of phosphoenolopyruvate and inorganic phosphate in the treated cells were similarly inhibited depending on the pyridoxal 5-P concentration. The major integral membrane protein, Band 3, was preferentially labelled by treating erythrocytes with pyridoxal 5-P/[^3H]-NaBH_4. These results suggest that Band 3 mediates the transport of phosphenolopyrvate as well as inorganic phosphate.
東海大学の論文
1982-06-14