Castro-Gomes Thiago, Almeida-Campos Flávia Regina, Calzavara-Silva Carlos Eduardo, da Silva Rosiane Aparecida, Frézard Frédéric, Horta Maria Fátima
Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.
FEBS Lett. 2009 Oct 6;583(19):3209-14. doi: 10.1016/j.febslet.2009.09.005. Epub 2009 Sep 6.
To lyse cells, some pore-forming proteins need to bind to receptors on their targets. Studying the binding requirements of Leishmania amazonensis leishporin, we have shown that protease-treated erythrocytes are as sensitive to leishporin-mediated lysis as untreated cells, indicating that protein receptors are dispensable. Similarly, carbohydrate receptors do not seem to be needed, since several sugars do not inhibit leishporin-mediated hemolysis. Conversely, dipalmitoylphosphatidylcholine (DPPC), but not cholesterol, completely inhibits leishporin-mediated lysis. DPPC liposomes, with or without cholesterol, are lysed by leishporin and remove its lytic activity. Our results demonstrate that leishporin is a cholesterol-independent cytolysin that binds directly to phospholipids.
为了裂解细胞，一些成孔蛋白需要与其靶标上的受体结合。在研究亚马逊利什曼原虫利什孢素的结合需求时，我们发现经蛋白酶处理的红细胞对利什孢素介导的裂解与未处理的细胞一样敏感，这表明蛋白质受体并非必需。同样，碳水化合物受体似乎也不需要，因为几种糖类并不能抑制利什孢素介导的溶血作用。相反，二棕榈酰磷脂酰胆碱（DPPC）而非胆固醇能完全抑制利什孢素介导的裂解。含或不含胆固醇的DPPC脂质体可被利什孢素裂解并消除其裂解活性。我们的结果表明，利什孢素是一种不依赖胆固醇的溶细胞素，可直接与磷脂结合。
