Cell-Free Science and Technology Research Center and Venture Business Laboratory, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan.
Biochem Biophys Res Commun. 2011 Oct 28;414(3):612-7. doi: 10.1016/j.bbrc.2011.09.130. Epub 2011 Oct 2.
The malaria parasite, Plasmodium falciparum, was recently shown to operate a branched pathway of tricarboxylic acid (TCA) metabolism. To identify and characterize membrane transporters required for such TCA metabolism in the parasite, we isolated a cDNA for a dicarboxylate-tricarboxylate carrier homolog (PfDTC), synthesized the encoded protein with the use of a cell-free translation system, and determined the substrate specificity of its transport activity with a proteoliposome reconstitution system. PfDTC was found to mediate efficient oxoglutarate-malate, oxoglutarate-oxaloacetate, or oxoglutarate-oxoglutarate exchange across the liposome membrane. Our results suggest that PfDTC may mediate the oxoglutarate-malate exchange across the inner mitochondrial membrane required for the branched pathway of TCA metabolism in the malaria parasite.
疟原虫，恶性疟原虫，最近被证明采用三羧酸（TCA）代谢的分支途径。为了鉴定和描述寄生虫中 TCA 代谢所需的膜转运蛋白，我们分离了一个二羧酸-三羧酸载体同源物（PfDTC）的 cDNA，使用无细胞翻译系统合成了编码的蛋白，并使用蛋白脂质体重建系统确定了其转运活性的底物特异性。PfDTC 介导了有效的草酰琥珀酸-苹果酸、草酰琥珀酸-草酰乙酸或草酰琥珀酸-草酰琥珀酸交换穿过脂质体膜。我们的结果表明，PfDTC 可能介导疟原虫 TCA 代谢分支途径所需的线粒体基质内膜中的草酰琥珀酸-苹果酸交换。
