X射线溶液散射揭示了乳铁蛋白、血清转铁蛋白和卵转铁蛋白在摄取铁时的构象变化。

X-ray solution scattering reveals conformational changes upon iron uptake in lactoferrin, serum and ovo-transferrins.

作者信息

Grossmann J G, Neu M, Pantos E, Schwab F J, Evans R W, Townes-Andrews E, Lindley P F, Appel H, Thies W G, Hasnain S S

机构信息

Molecular Biophysics Group, SERC Daresbury Laboratory, Cheshire, U.K.

出版信息

J Mol Biol. 1992 Jun 5;225(3):811-9. doi: 10.1016/0022-2836(92)90402-6.

DOI:10.1016/0022-2836(92)90402-6

PMID:1602483

Abstract

X-ray solution scattering has been used for studying the structural changes that take place upon uptake and release of iron from serum and chicken ovo-transferrin and human lactoferrin. In the case of chicken ovo-transferrin, data have been obtained for both the intact protein and the isolated N and C-lobes with and without iron. These studies reveal that both lobes undergo a change that is consistent with an opening of the inter-domain cleft when iron is removed from the protein. We suggest that the conformational change of the protein increases the specificity of receptor binding and that the closed configuration of the iron-loaded protein is one, or perhaps the, decisive step in the mechanism for receptor-mediated endocytosis.

摘要

X射线溶液散射已被用于研究血清、鸡卵转铁蛋白和人乳铁蛋白摄取和释放铁时发生的结构变化。对于鸡卵转铁蛋白，已获得完整蛋白质以及分离的N端和C端结构域在有铁和无铁情况下的数据。这些研究表明，当铁从蛋白质中去除时，两个结构域都会发生变化，这种变化与结构域间裂隙的打开相一致。我们认为，蛋白质的构象变化增加了受体结合的特异性，并且铁负载蛋白质的封闭构象是受体介导的内吞作用机制中的一个决定性步骤，甚至可能是决定性步骤。