NMR solution structure of the receptor binding domain of human α2-macroglobulin
NMR solution structure of the receptor binding domain of human α2-macroglobulin
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DOI：
10.1074/jbc.275.2.1089
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发表时间：
2000-01-14
影响因子：
4.8
通讯作者：
Gettins, PGW
中科院分区：
文献类型：
--
作者：
Huang, W;Dolmer, K;Gettins, PGW
人α（2）-巨球蛋白-蛋白酶复合物通过离散的138个残基的C-末端受体结合结构域（RBD）与其受体低密度脂蛋白受体相关蛋白（LRP）结合，该受体结合结构域也与β-淀粉样肽结合。我们已经使用NMR光谱对重组表达的均匀C-13/N-15标记的人RED来确定其在溶液中的三维结构，人RED是两个反平行β-折叠的三明治，一个四链和一个五链，并且还包含一个2.5圈的α-螺旋和额外的1圈。螺旋区主要的α-螺旋在外表面上含有两个赖氨酸残基，已知这两个赖氨酸残基对于受体结合是必需的。钙结合位点（K-d类似于11 mM）存在于β-夹心的一端的环区域中。钙结合主要影响该环区域，并且不显著干扰结构域的稳定核心结构。结构和NMR。分配将使我们能够在溶液中检测RED与受体结构域和β-淀粉样肽的特异性结合。
Human alpha(2)-macroglobulin-proteinase complexes bind to their receptor, the low density lipoprotein receptor-related protein (LRP), through a discrete 138-residue C-terminal receptor binding domain (RBD), which also binds to the beta-amyloid peptide. We have used NMR spectroscopy on recombinantly expressed uniformly C-13/N-15-labeled human RED to determine its three-dimensional structure in solution, Human RED is a sandwich of two antiparallel beta-sheets, one four-strand and one five-strand, and also contains one alpha-helix of 2.5 turns and an additional 1-turn. helical region. The principal alpha-helix contains two lysine residues on the outer face that are known to be essential for receptor binding. A calcium binding site (K-d similar to 11 mM) is present in the loop region at one end of the beta-sandwich, Calcium binding principally affects this loop region and does not significantly perturb the stable core structure of the domain. The structure and NMR. assignments will enable us to examine in solution specific binding of RED to domains of the receptor and to beta-amyloid peptide.