重金属离子与细胞内钙离子结合蛋白的亲和力。

Affinity of heavy metal ions to intracellular Ca2+-binding proteins.

作者信息

Richardt G, Federolf G, Habermann E

出版信息

Biochem Pharmacol. 1986 Apr 15;35(8):1331-5. doi: 10.1016/0006-2952(86)90278-9.

Abstract

Parvalbumin, troponin C and vitamin D dependent Ca2+-binding proteins (CaBP type I and II) share the property of calmodulin to interact with some heavy metal ions. In flow dialysis and in spot tests the affinities of Cd2+ and Pb2+ to these proteins were comparable to those of Ca2+. The relative affinities were for calmodulin: Pb2+ greater than Ca2+ greater than Cd2+, for troponin C: Ca2+ greater than Cd2+ greater than Pb2+, for CaBP I: Ca2+ approximately Pb2+, for CaBP II; Ca2+ greater than Pb2+ greater than Cd2+, and for parvalbumin: Cd2+ approximately Ca2+ greater than Pb2+. Upon gel filtration of the supernatant of a pig mucosal homogenate, binding for both Pb2+ and Ca2+ appeared in the MW range of 10,000, together with CaBP II. We conclude that the investigated proteins bind heavy metal ions, in particular Pb2+ and Cd2+, similar to calmodulin. Their role in transport, storage and toxicity remains to be assessed.

摘要

小清蛋白、肌钙蛋白C和维生素D依赖性钙结合蛋白（I型和II型钙结合蛋白）具有与钙调蛋白相同的特性，即能与某些重金属离子相互作用。在流动透析和点滴试验中，镉离子和铅离子对这些蛋白质的亲和力与钙离子相当。其相对亲和力为：对钙调蛋白而言，铅离子＞钙离子＞镉离子；对肌钙蛋白C而言，钙离子＞镉离子＞铅离子；对I型钙结合蛋白而言，钙离子≈铅离子；对II型钙结合蛋白而言，钙离子＞铅离子＞镉离子；对小清蛋白而言，镉离子≈钙离子＞铅离子。对猪黏膜匀浆上清液进行凝胶过滤时，铅离子和钙离子的结合出现在分子量为10,000的范围内，同时伴有II型钙结合蛋白。我们得出结论，所研究的蛋白质与钙调蛋白类似，能结合重金属离子，尤其是铅离子和镉离子。它们在运输、储存和毒性方面的作用仍有待评估。