Department of Medical Biochemistry, University of Medicine in Wroclaw, ul. Chalubinskiego 10, 50-368 Wroclaw, Poland.
Z Naturforsch C J Biosci. 2009 Sep-Oct;64(9-10):754-8. doi: 10.1515/znc-2009-9-1023.
Enolase detected on the cell surface may be a receptor for certain ligands, especially for plasminogen. It is important for the pathogen invasiveness and in the development of a tumour. Therefore, we sought to preliminarily determine the enolase location and catalytic activity in the subfractions of MCF-7 cells. The latter was done on intact cells and in subfractions of MCF-7 cells. We identified enolase by immunoblotting. The binding of human plasminogen to enolase was performed by immunoblotting using monoclonal antibodies against plasminogen. The intact MCF-7 cells demonstrated activity of enolase. Enolase in postnuclear and perinuclear fractions is catalyticly active too. We identified the enolase protein in immunoblots of these fractions, except for the nuclear subfraction. These results provide evidence that enolase is present on the intact surface of MCF-7 cells and in post- and perinuclear fractions. The surface protein maintained catalytic activity, which suggests that its location in the plasma membrane didn't change the active centre of the enzyme.
细胞表面的烯醇酶可能是某些配体的受体，尤其是纤溶酶原。它对于病原体的侵袭和肿瘤的发展很重要。因此，我们试图初步确定 MCF-7 细胞亚组分中的烯醇酶位置和催化活性。后者是在完整细胞和 MCF-7 细胞亚组分上进行的。我们通过免疫印迹鉴定烯醇酶。使用针对纤溶酶原的单克隆抗体通过免疫印迹进行人纤溶酶原与烯醇酶的结合。完整的 MCF-7 细胞表现出烯醇酶的活性。核后和核周部分的烯醇酶也具有催化活性。除了核亚组分外，我们在这些部分的免疫印迹中鉴定出了烯醇酶蛋白。这些结果提供了证据表明，烯醇酶存在于 MCF-7 细胞的完整表面以及核后和核周部分。表面蛋白保持催化活性，这表明其在质膜中的位置并未改变酶的活性中心。
